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1.
BACKGROUND: How to use traditional Chinese medicine to intervene the imbalance of autophagy after intestinal mucosal barrier injury, so as to ultimately intervene the occurrence of gastrointestinal acute graft-versus-host disease, is an urgent problem to be solved after hematopoietic stem cell transplantation. OBJECTIVE: To verify the precise mechanism by which Huangqin Decoction interferes with acute intestinal graft-versus-host disease. METHODS: CB6F1 mice were randomly divided into normal control group, model control group, low-dose Huangqin Decoction group, medium-does Huangqin Decoction group and high-does Huangqin Decoction group, with 16 mice per group. CB6F1 mice in the model control group, low-dose Huangqin Decoction group, medium-does Huangqin Decoction group and high-does Huangqin Decoction group were infused with mononuclear cell suspension (bone marrow cell 8×107 + spleen cell 8×107) obtained from Balb/c mice via caudal vein within 4 hours after60Co whole body irradiation (radiation dose was 8 Gy). Different concentrations of Huangqin Decoction were given by gavage on the same day after modeling. The rats in the model control group and the normal control group were given the same volume of normal saline by gavage for 15 days. Eight hours after the last gavage, the small intestine tissues of six mice in each group were collected. PCR and western blot assay were used to detect the expression levels of LC3II/I, Beclin1 and P62. The pathological grading of small intestinal mucosa was scored by hematoxylin-eosin staining. The autophagic vesicle structure of small intestinal mucosal epithelial cells was observed by transmission electron microscope. The remaining 10 rats in each group (except the normal control group) were used to observe the clinical grading of acute graft-versus-host disease and record the survival time. RESULTS AND CONCLUSION: (1) After the application of Huangqin Decoction, the survival time of mice was significantly prolonged; the clinical acute graft-versus-host disease score was significantly decreased, and the pathological grading score of small intestinal mucosa was significantly decreased. The score of medium-does Huangqin Decoction group and high-does Huangqin Decoction group was significantly lower than that of model control group, but there was no significant difference between medium-does Huangqin Decoction group and high-does Huangqin Decoction group. (2) The LC3II/I and Beclin1 expression was significantly lower in the model control group than that in the normal control group (P < 0.01), and P62 expression was significantly higher than that in the normal control group (P < 0.01). Huangqin Decoction could promote the recovery of LC3II/I and Beclin1 levels and downregulate p62 levels (P < 0.01). (3) Under transmission electron microscope, the number of autophagic vesicles in the treatment group was significantly higher than that in the model control group, accompanied by the recovery of important organelles such as mitochondria. (4) The results confirm that by interfering autophagy related proteins, Huangqin Decoction can promote the recovery of autophagy in acute graft-versus-host disease, protect intestinal mucosal barrier and reduce intestinal rejection after transplantation and has promise as a new treatment for acute graft-versus-host disease. © 2022, Publishing House of Chinese Journal of Tissue Engineering Research. All rights reserved.  相似文献   

2.
BACKGROUND: Insufficient oral soft tissues in the implant zone may have a negative effect on the wound healing and the aesthetic restoration in the late stage. Platelet-rich fibrin can promote the wound healing of soft tissue defects. But there is still a lack of in-depth studies on the promotion of oral soft tissue defects in animal experiments. OBJECTIVE: To compare the repairing effects of platelet-rich fibrin and collagen membrane on soft tissue defects of the hard palate in New Zealand rabbits. METHODS: Fifty-four New Zealand rabbits were randomly divided into three groups (n=14 per group): platelet-rich fibrin group, collagen membrane group and blank control group. A 5 mm-diameter circular full-thickness soft tissue defect was made in the front of the hard palate, 2 mm distant to the rear maxillary incisors and mucosal edge of the bilateral hard palates. Autologous platelet-rich fibrin membrane or collagen membrane were implanted into the defect in the platelet-rich fibrin group and collagen membrane group, respectively. No treatment was given in the blank control group. General observation of the wound and wound healing analysis were performed at days 3, 7, 14, 21, 28, 56 post operation. Hematoxylin-eosin staining, CD31 immunohistochemical staining and Masson staining were used to observe inflammatory reaction, angiogenesis and collagen formation in the surgical site. RESULTS AND CONCLUSION: The wound healing rate was fastest in the platelet-rich fibrin group, and no obvious scar formed. At 3 days post operation, there was no difference in the wound healing rates among the three groups; at 7 days, the wound healing rate in the platelet-rich fibrin group was significantly higher than that in the collagen membrane group and blank control group (P < 0.05). At 3 and 7 days after operation, the inflammatory reaction in the platelet-rich fibrin group was less than that in the collagen membrane and blank control groups (P < 0.05); at 14, 21, 28 and 56 days, there was no significant difference between the three groups. At 7, 14, 21 days after operation, the average absorbance value of CD31 in the platelet-rich fibrin group was significantly higher than that in the collagen membrane and blank control groups (P < 0.05). The average absorbance value of collagen formation in the platelet-rich fibrin group was significantly higher than that in the collagen membrane and blank control groups at 7 days after operation (P < 0.05), significantly higher than that in the blank control group at 14 days (P < 0.05), but lower than that in the collagen membrane and blank control groups at 21, 28 and 56 days after operation (P < 0.05). These findings show that platelet-rich fibrin can reduce inflammatory reactions in the process of wound healing, accelerate the angiogenesis, regulate the metabolism of collagen, reduce the formation of scar and improve the quality of wound healing, thereby promoting the repair of oral soft tissue defects. 中国组织工程研究杂志出版内容重点:组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程  相似文献   

3.
BACKGROUND:Proteoglycan, chondroitin sulfate and keratan sulfate, and hyaluronic acid are important substances in the maintenance of intervertebral discs of normal structure. They impact the physiological function of intervertebral disc. OBJECTIVE: To observe the influence of Liuwei Dihuang Wan on proteoglycan in rabbit models of intervertebral disc degeneration, and to study the efficacy of Liuwei Dihuang Wan on prevention and treatment of intervertebral disc degeneration. METHODS: 80 New Zealand rabbits were randomly divided into Liuwei Dihuang Wan group, model group, sham surgery group and blank control group (n=20 per group). Animal models of intervertebral disc degeneration were established in the model and Liuwei Dihuang Wan groups. In the sham surgery group, surgery via the same approach to expose the lumbar spine was conducted followed by layer-by-layer suturing. In the Liuwei Dihuang Wan group, rabbits were given 10 mg/kg Liuwei Dihuang Wan by lavage, once a day. In the model group, sham surgery group and blank control group, rabbits were given an equal volume of physiological saline, once a day, by natural feeding. At 2, 4, 6 and 8 weeks, five rabbits from each group were sacrificed, and intervertebral disc specimens were taken to measure proteoglycan components in the intervertebral disc.  RESULTS AND CONCLUSION: With the extension of feeding time, Liuwei Dihuang Wan could increase sugar amino polysaccharide content, chondroitin sulfate/acid ratio of keratin, and hyaluronic acid content in the intervertebral disc degeneration model, and stabilized the proteoglycan content. Thus, it delayed the degeneration of the intervertebral disc to a certain extent. 中国组织工程研究杂志出版内容重点:组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程  相似文献   

4.
BACKGROUND: Articular cartilage injuries can result from a variety of causes. Conventional therapy cannot obtain the optimal clinical results. Low-intensity pulsed ultrasound has been shown to promote the repair of injured articular cartilage. OBJECTIVE: To investigate the effects of low-intensity pulsed ultrasound on the repair of injured articular cartilage. METHODS: Twenty New Zealand white rabbits were used to establish knee arthritis models and equally randomized into study and control groups, respectively. Rabbits in the study group received low-intensity pulsed ultrasound treatment, and sham low-intensity pulsed ultrasound treatment was given in the control group. At 8 weeks after treatment, pathological change and histological scores in articular cartilage tissue collected from both groups were determined. Moreover, the ultrastructure and type II collagen expression of chondrocytes were determined. Matrix metalloproteinase-13 mRNA expression was detected by quantitative real-time PCR. RESULTS AND CONCLUSION: At 8 weeks after treatment, toluidine blue staining showed a disordered arrangement of cells, decreased number of cartilage cells in each layer and cluster in the control group. Light disordered arrangement of cells, decreased appearance of the superficial layer cells and the cluster phenomenon were observed in the study group. Articular cartilage tissue scores were significantly decreased in the study group compared with the control group (P < 0.05). The chondrocytes were small, enlarged intracellular mitochondria and rough endoplasmic reticulum, cytoplasmic swelling, collagen fibrils coarse, well developed Golgi apparatus, and nuclear fragmentation were observed in the control group. In addition, the normal structure of organelles disappeared and cell degeneration was observed in the control group. In the study group, the size of chondrocytes and the Golgi complex and other organelles were normal, and the protein polysaccharide granules were observed in the cytoplasm and membrane. The mRNA expression of matrix metalloproteinase-13 in the study group was significantly lower than that in the control group (P < 0.05). Type II collagen immunoreactivity in the study group was stronger than that in the control group. No incision infection, suppuration, red swelling appeared in all rabbits. Our results suggest that low-intensity pulsed ultrasound can be used for the treatment of articular cartilage injury by alleviating the degradation of collagen type II and inhibiting the expression of matrix metalloproteinase-13. 中国组织工程研究杂志出版内容重点:组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程  相似文献   

5.
BACKGROUND: Granulocyte colony-stimulating factor has been shown to be used for the treatment of granulocytopenia, but its effect on sepsis is little reported. OBJECTIVE: To explore the treatment outcomes of recombinant human granulocyte macrophage colony stimulating factor (rhGM-CSF) for sepsis mice. METHODS: A sepsis mouse model was established by intraperitoneal injection of lipopolysaccharide, and then given subcutaneous injection of rhGM-CSF at 6 and 30 hours after modeling. The morphological change of mouse lung tissue, CD64 expression in peripheral neutrophils, and serum levels of tumor necrosis factor-α and interleukin-10 were ovserved, respectively. RESULTS AND CONCLUISON:(1) Complete bronchial epithelial, mild stromal hyperplasia, and a few neutrophil infiltration were found after rhGM-CSF treatment. (2) CD64 expression in peripheral neutrophils, and serum level of interleukin-10 in the treatment group were significantly higher than those in the model and control groups at 1, 3 and 7 days after treatment (P < 0.05). The serum level of tumor necrosis factor-α in the treatment group was significantly higher than that in the control group, but lower than that in the model group after 1, 3 and 7 days of treatment (P < 0.05). (4) These results show that rhGM-CSF can enhance neutrophil function and the anti-inflammatory effects in sepsis mice. 中国组织工程研究杂志出版内容重点:肾移植;肝移植;移植;心脏移植;组织移植;皮肤移植;皮瓣移植;血管移植;器官移植;组织工程  相似文献   

6.
Objective To evaluate the effect of TLR2McAb and TLR4McAb on intestinal flora of DSS-induced colitis in mice. Methods Fifty healthy male BALB/c mice (SPF level), were randomly assigned into five groups: the control group( group A), the UC model group( group B), TLR2McAb intervention group( group C), TLR4McAb intervention group( group D) and TLR2McAb + TLR4McAb intervention group(group E). Clinical symptoms were evaluated by the disease activity index(DAI), while tissue sam ples were evaluated by histological scoring(HS). The quantities of mRNA for IFN-γ, IL-4 and IL-17 were determined by real-time PCR. Meanwhile, fecal samples were obtained directly from the cecum for microbiological studies. Results After the treatment with TLR2McAb and TLR4McAb, DAI and HS were decreased significantly. Compared with group A, inflammatory cytokines such as IFN-γ, IL-4 and IL-17 in group B were higher. Compared with group B, expression of these three cytokines in group C to E was all markedly decreased. Group A showed a considerable predominance of Lactobacillus spp and Bifidobacterium spp,while the UC model group showed a conspicuous increase of Escherichia coli and decreases of Lactobacillus spp and Bifidobacterium spp. After treatment with TLR2McAb or/and TLR4McAb, Lactobacillus spp and Bifidobacterium spp increased to the normal level. But counts of E. Coli in the three intervention groups were not changed. Conclusion TLR2McAb and TLR4McAb suppressed the development of DSS-induced colitis and increase cecum counts of Lactobacilli and Bifidobacteria.  相似文献   

7.
Objective To evaluate the effect of TLR2McAb and TLR4McAb on intestinal flora of DSS-induced colitis in mice. Methods Fifty healthy male BALB/c mice (SPF level), were randomly assigned into five groups: the control group( group A), the UC model group( group B), TLR2McAb intervention group( group C), TLR4McAb intervention group( group D) and TLR2McAb + TLR4McAb intervention group(group E). Clinical symptoms were evaluated by the disease activity index(DAI), while tissue sam ples were evaluated by histological scoring(HS). The quantities of mRNA for IFN-γ, IL-4 and IL-17 were determined by real-time PCR. Meanwhile, fecal samples were obtained directly from the cecum for microbiological studies. Results After the treatment with TLR2McAb and TLR4McAb, DAI and HS were decreased significantly. Compared with group A, inflammatory cytokines such as IFN-γ, IL-4 and IL-17 in group B were higher. Compared with group B, expression of these three cytokines in group C to E was all markedly decreased. Group A showed a considerable predominance of Lactobacillus spp and Bifidobacterium spp,while the UC model group showed a conspicuous increase of Escherichia coli and decreases of Lactobacillus spp and Bifidobacterium spp. After treatment with TLR2McAb or/and TLR4McAb, Lactobacillus spp and Bifidobacterium spp increased to the normal level. But counts of E. Coli in the three intervention groups were not changed. Conclusion TLR2McAb and TLR4McAb suppressed the development of DSS-induced colitis and increase cecum counts of Lactobacilli and Bifidobacteria.  相似文献   

8.
BACKGROUND: Acupuncture of “Xingnao Kaiqiao” can treat cerebral palsy by increasing cerebral blood flow, decreasing inflammatory reaction and promoting cerebral nerve repair. OBJECTIVE:To explore the influence of acupuncture of “Xingnao Kaiqiao” on behavior of immature rats with cerebral palsy and the underlying mechanism. METHODS: (1) The immature rat model of cerebral palsy was established and then randomized into control, model and acupuncture groups. (2) The immature rats in the acupuncture group were treated with acupuncture at major points of Neiguan (P 6), Renzhong (Du 26) and Sanyinjiao (Sp 6), as well as auxiliary points of Jiquan (H 1), Chize (Lu 5) and Weizhong (UB 40), while the model and control groups received no intervention. (3) Twenty-four days later, the body mass and the time removing the mackintosh at forepassed center were measured and recorded, the spatial learning and memory ability was detected by Mortis water maze test, and the serum levels of tumor necrosis factor alpha and interleukin-6 were detected by ELISA. RESULTS AND CONCLUSION: (1) The order of the body mass gained was as follows: control group > acupuncture group > model group (P < 0.05). (2) The time removing the mackintosh at forepassed center was the longest in the model group, followed by the acupuncture group, and shortest in the control group (P < 0.05). (3) Acupuncture method significantly improved the cognitive ability of immature rats, and reduced the latency of searching for platform and swimming distance compared with the model group (P < 0.05). (4) The serum levels of tumor necrosis factor alpha and interleukin-6 in the acupuncture group were significantly lower than those in the model group (P < 0.05). (5) In conclusion, the acupuncture of “Xingnao Kaiqiao” can improve the symptoms and cognitive ability of the immature rat model of cerebral palsy by up-regulating the serum levels of tumor necrosis factor alpha and interleukin-6. 中国组织工程研究杂志出版内容重点:肾移植;肝移植;移植;心脏移植;组织移植;皮肤移植;皮瓣移植;血管移植;器官移植;组织工程  相似文献   

9.
BACKGROUND: Phenylephrine has been proved to exert a protective effect on radiant-induced salivary gland and epithelial cell injuries, but its effect on hydrogen peroxide (H2O2)-induced oxidative stress in osteoblasts are not fully understood. OBJECTIVE: To explore the effect of phenylephrine on H2O2-induced oxidative stress in osteoblasts, and to explore the mechanism underlying the regulation by the expression level of nicotinamide phosphoribosyltransferase (Nampt). METHODS: Primary osteoblasts were cultured and randomly divided into four groups: blank control group, H2O2 group, phenylephrine group, and combination group (0.5 hour pretreatment of 1×10-5 mol/L phenylephrine, and then given 300 µmol/L H2O2). The morphology of osteoblasts was observed at different time points. Osteoblasts were collected after 24-hour culture, and total RNA and protein were then extracted to detect the mRNA and protein expression levels of Nampt by RT-PCR and western blot assay, respectively. RESULTS AND CONCLUSION: Compared with the blank control group, reduced osteoblasts and evident cell shrinks were observed in the H2O2 group, while the number of osteoblasts significantly increased in the combined group compared with the H2O2 group at 12, 24 and 48 hours of culture. RT-PCR results showed that the mRNA level of Nampt in the H2O2 group was reduced by 31.23% of that in the blank control group, while the mRNA level of Nampt in the combination group was dramatically increased by 206.20% of that in the H2O2 group at 24 hours of culture (both P < 0.05). Furthermore, western blot assay findings revealed that the protein level of Nampt in the H2O2 group was reduced by 67.98% of that in the blank control group, while the protein level of Nampt in the combination group was increased by 152.25% of that in the H2O2 group at 24 hours of culture (both P < 0.05). Our results indicate that phenylephrine can alleviate the shrink and atrophy of osteoblasts caused by H2O2, thereby exerting protective effect by up-regulating the mRNA and protein levels of Nampt that may be a regulatory gene. © 2018, Journal of Clinical Rehabilitative Tissue Engineering Research. All rights reserved.  相似文献   

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11.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

12.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

13.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

14.
There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.  相似文献   

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16.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

17.
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.  相似文献   

18.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

19.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   

20.
Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.  相似文献   

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