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1.
Genetic polymorphism of rabbit VHa region: a new allotype, a108   总被引:1,自引:0,他引:1  
We report a new rabbit IgVH allotype, designated a108, which was detected following studies of the progeny of a wild rabbit (Oryctolagus cuniculus) from Zembra Island (Tunisia). This allotype seems to be specific of this island, since it has not been detected in other wild rabbit populations (in Spain, Portugal or France). Its determinants are located on the Fd fragment of the immunoglobulin (Ig) heavy chain and it behaves like the product of an allele at the alpha locus. Allotype a108 was strongly related serologically to a1 and a107, and to a lesser extent to a101, a109 and a3 allotypes. We also detected determinants shared among the a1, a107, a108, a101 and a109 allotypes. These determinants were expressed by a large fraction of Ig molecules from rabbits of allotype a1, a107 and a108 and by a very small fraction of Ig from rabbits of allotype a101 and a109.  相似文献   

2.
When a novel variant is found in a patient and not in a group of controls, it becomes a candidate for the disease-causing mutation in that patient. At present, no sampling theory exists for assessing the probability that the novel SNP might actually be a neutral variant. We have developed a population genetics-based method for calculating a P-value for a mutation-detection effort. Our method can be applied to a heterozygous patient, a homozygous patient, with or without inbreeding, or to a patient who is a compound heterozygote. Additionally, the method can be used to calculate the probability of finding a neutral variant at frequencies that differ between a group of patients and a group of controls, given some length of sequence examined. This method accounts for the multiple testing that is inherent in identification of variants through sequencing, to be used in subsequent case-control analyses. We show, for example, that for complete resequencing of 10 kb, the probability of finding a neutral variant in a patient and not in 50 controls is about 15%. Thus, discovery of a variant in a patient and not in a group of controls is, on its own, very weak evidence of involvement with disease.  相似文献   

3.
The ultrastructure of two types of sense receptors each is described for Gieysztoria and Rhinolasius. In Gieysztoria, one receptor possesses a number of long microvilli, a cilium with a cross-striated rootlet, a septate desmosome, and an electron-dense band apical to the desmosome. The band forms a complex reticulate extension into the base of the receptor. The second receptor is without microvilli, has a cilium with a long cross-striated rootlet, and a septate desmosome with a short basal electron-dense extension or extensions which do not form a complete ring. In Rhinolasius, one receptor possesses a short bulbous cilium without a rootlet, with a septate desmosome of the pleated sheet (comb) type and a weakly developed electron-dense band beneath it. The second receptor has a long cilium with cross-striated rootlet, and a septate desmosome with a weakly developed electron-dense band apical to it. Centrioles were found in nerve fibres of both species.  相似文献   

4.
So far, three subtypes of the F4 (K88) fimbrial antigen of porcine enterotoxigenic Escherichia coli, F4ab, F4ac, and F4ad, have been distinguished by using polyclonal antisera in agglutination and precipitation tests. The a factor represents one or more common epitopes, whereas each of the b, c, and d factors represents one or more subtype-specific epitopes. We further characterized the F4 antigen complex by using a panel of 40 F4-specific monoclonal antibodies (MAbs). The specificity of all MAbs was proven by enzyme-linked immunosorbent assays, agglutination and radioimmunoprecipitation tests, and immunoelectron microscopy. The MAbs either reacted with all F4 subtypes, reacted with two subtypes, or were subtype specific. Epitope analysis by competition enzyme-linked immunosorbent assays revealed at least 11 epitope clusters on the F4 antigen complex, designated a1 to a7, b1, b2, c, and d. The following antigenic formulas were found for the F4 subtypes: F4ab, a1a2a3a4a5a6b1b2; F4ac, a1a2a3(a4)a5a6a7c; and F4ad, a1a2a3a4a7d. All MAbs were directed against conformational epitopes located on the 27,500-dalton major fimbrial subunits. Consequences for the replacement of polyclonal antisera by MAbs in diagnostic tests are discussed.  相似文献   

5.
Wnt-3a is a representative ligand that activates the beta-catenin-dependent pathway in Wnt signaling and is modified with glycans and palmitate. In this study, we analyzed the relationship between glycosylation and lipidation of Wnt-3a. Secretion of a Wnt-3a mutant that lacks glycosylation (Wnt-3a NQ) was impaired. Wnt-3a C77A, which lacks palmitoylation at Cys77, was secreted with similar efficiency to wild-type Wnt-3a (Wnt-3a WT), but did not induce the internalization of low-density lipoprotein receptor-related protein 6 (LRP6). Furthermore, removal of palmitate from Wnt-3a suppressed the ability to bind to its receptors Frizzled8 and LRP6. Wnt-3a C77A was glycosylated to an extent similar to Wnt-3a WT, while Wnt-3a NQ was not modified with palmitate. Expression of porcupine, which is a putative acyltransferase, enhanced palmitoylation of Wnt-3a WT greatly, but that of Wnt-3a NQ slightly. While Wnt-3a WT was present in both the endoplasmic reticulum (ER) and Golgi, Wnt-3a NQ was located to the ER only. Furthermore, Wnt-3a was not palmitoylated but was glycosylated in the cells treated with Brefeldin A, which inhibits transport of vesicles from the ER to the Golgi. These results indicate that glycosylation of Wnt-3a precedes palmitoylation and that both modifications are necessary for secretion of an active Wnt-3a.  相似文献   

6.
BACKGROUND. Compared with other clinical disciplines, academic general practice is in a difficult situation with respect to patient care. There are at least three different possible models of working arrangements for heads of departments of general practice: to work in a surgery in a medical school; to work in a surgery in the community, separate from a part-time university post; or to work part-time in a surgery in the community, separate from a university post. AIM. A study was undertaken to explore these models and to gain an understanding of academic teachers' organization of patient care in Europe. METHOD. A total of 77 heads of departments in universities in 12 European countries were sent a questionnaire enquiring about important characteristics of their department, the number of patients they treated per week and how they allocated their time. RESULTS. Sixty nine heads of department (90%) responded. Of respondents, 55% worked part-time in a surgery, separate from a university post, nearly one third worked mainly in a surgery, separate from a part-time university post, and 16% worked in a surgery in a medical school. Those working in a surgery with only a part-time university post spent most time in patient care compared with those working in other models (mean of 57%). Respondents working in a surgery in a medical school spent most time on administration (34%); they spent 22% of their time on patient care and 20% on education. Respondents working in a surgery in a medical school spent 25% of their time on research, those working in a surgery separate from a part-time university post spent 12% of their time on research, and those working mainly in a university with a part-time practice post spent 24% of their time on research. Those working mainly in a university post spent only 17% of their time in patient care. CONCLUSION. Working in a surgery in a medical school represented a well-balanced model of time allocation between patient care, research and education and seemed to be a good approach for the integration of general practice into medical schools. Working part-time in a surgery with a university post is an appropriate model for academic integration, but patient care seemed to be neglected. Those doctors working mainly in the community with a part-time university post were able to provide continuity of care and to come into close contact with the everyday problems of general practitioners. However, they might have to struggle for academic recognition.  相似文献   

7.
We report on a 4 1/2-year-old girl with clinical features of Teebi hypertelorism syndrome (THS), including a prominent forehead with a widow's peak, heavy and broad eyebrows, hypertelorism, long palpebral fissures, ptosis, a thin upper lip, a grooved chin, and a left preauricular cyst. She required a pacemaker for third degree atrioventricular (AV) block, a finding that has not been previously reported in 36 other patients with THS and for which we were unable to identify other causes. We have reviewed the previous reports of THS and note a characteristic facial appearance with hypertelorism, heavy, broad, and arched eyebrows, a thin upper lip with a long and deep philtrum, and a prominent forehead. Structural cardiac defects were present in five patients, implying that cardiac investigations are warranted in patients with a cardiac murmur and a clinical diagnosis of THS.  相似文献   

8.
We report on two sib fetuses, products of a consanguineous union, who had multiple and apparently unrelated malformations. The first fetus, a female, had trilobed lungs, a single cardiac ventricle, asplenia, situs ambiguus of the liver, and a lumbosacral meningomyelocele. The brain of this fetus was normal. The second fetus, a male, had bilobed lungs, a single cardiac ventricle, situs solitus of the abdominal organs and spleen, and a semilobar holoprosencephaly. The occurrence of these malformations in sibs of different sexes and the parental consanguinity suggest a recessive mutation in a gene responsible for both heterotaxy and midline defects, including holoprosencephaly. Am. J. Med. Genet. 84:373–376, 1999. © 1999 Wiley-Liss, Inc.  相似文献   

9.
Based on a series of self-reports of a previously undescribed and undocumented experiential event, we are postulating the existence of a newly identified state of consciousness, daytime parahypnagogia (DPH). DPH is more likely to occur when one is tired, bored, suffering from attention fatigue, and/or engaged in a passive activity. Individuals describe DPH as a transient and fleeting episode that is dissociative, trance-like, dreamlike, uncanny, and often pleasurable; but, unlike a daydream, it is not self-directed. A DPH episode is spontaneous and may consist of a flash image, thought, and/or creative insight that is quickly forgotten. However, the individual remains aware of having had a DPH experience. This paper details the experiential characteristics associated with DPH. Through a brief review of the literature, the authors differentiate DPH from related phenomena and establish DPH as a unique and distinct altered state of consciousness.  相似文献   

10.
We report on a 6-year-old girl with linear streaks of apparent hypopigmentation and hyperpigmentation following the Blaschko lines, growth retardation, bupthalmos of the left eye, and mild mental retardation. She had a 45,X karyotype in lymphocytes. In cultured fibroblasts a double aneuploidy mosaicism was detected, consisting of a cell line with trisomy for chromosome 7 and a cell line with monosomy for the X-chromosome and no cell line with a normal karyotype. Cutis tricolor or three levels of pigmentation in different skin areas suggested presence of a third, probably normal cell line. Double aneuploidy mosaicism of a cell line with monosomy X and a cell line with trisomy of an autosome is a rare finding. The combination of monosomy X with trisomy of chromosomes 8, 10, 13, 18, and 21 has been reported, but not the combination with trisomy 7. In the 45,X cell line, microsatellite analysis showed loss of the maternal X-chromosome, and presence of a maternal and paternal chromosome 7. The 47,XX,+7 cell line showed a paternal and a maternal X-chromosome, and a paternal and two identical maternal chromosomes 7. Mechanisms that might explain this double aneuploidy mosaicism are discussed.  相似文献   

11.
12.
N. E. Eriksson 《Allergy》1990,45(4):285-292
The efficiency of the new screening tests for atopy, Phadiatop and CAP Phadiatop, was studied by comparing their results with a clinical diagnosis of atopy in 100 consecutive adults with asthma and/or rhinitis. Further, the diagnostic efficiency of a combination of Phadiatop and a few standardized questions was studied. The Phadiatop was found to have a specificity of 0.98, and a sensitivity of 0.92 and the CAP Phadiatop a specificity of 0.94 and a sensitivity of 0.96. When the Phadiatop was combined with a few questions, a sensitivity of 1.00 was achieved. It is concluded that Phadiatop and CAP Phadiatop have a higher diagnostic precision than other hitherto used methods for screening of atopic allergy. The place of Phadiatop in a diagnostic flow chart is suggested.  相似文献   

13.
The role of lipoprotein(a) (Lp[a]) as a significant and possibly causal cardiovascular disease (CVD) risk factor has been well established. Many studies, mostly experimental, have supported inflammation as a mediator of Lp(a)-induced increase in CVD risk. Lp(a), mainly through oxidized phospholipids bound to its apolipoprotein(a) part, leads to monocyte activation and endothelial dysfunction. The relationship between Lp(a) and inflammation is bidirectional as Lp(a) levels, besides being associated with inflammatory properties, are regulated by inflammatory stimuli or anti-inflammatory treatment. Reduction of Lp(a) concentration, especially by potent siRNA agents, contributes to partial reversion of the Lp(a) related inflammatory profile. This review aims to present the current pathophysiological and clinical evidence of the relationship between Lp(a) and inflammation.  相似文献   

14.
Human platelet antigen (HPA) systems consist of more than twelve bi-allelic antigen polymorphisms in which a base pair substitution leads to change in an amino acid of a glycoprotein expressed on the platelet. The neonatal alloimmune thrombocytopenia (NAIT), post transfusion purpura, and refractoriness to platelet transfusion can be induced by antibodies against human platelet antigens: e.g. HPA-1a, 3a, 4a, 5a, and Gova. HPA typing is essential for the diagnosis and treatment of a variety of diseases. We developed a PCR-based method to detect HPA-1 to HPA-13, Oe and Gov platelet alloantigens. In this method, the amplified PCR products were used to recognize the polymorphism after restriction enzyme digestions. Among 566 Taiwanese, 107 Indonesian, 100 Filipino and 137 Thai subjects studied, HPA-1a, 2a, 4a, 5a, 6a, 7aW, 8aW, 9a, 10a, 11a, 12a, 13a, Oea genes were present in every sample; while HPA-1b, 2b, 4b, 5b and 6b were rarely found. HPA-7aW, 8aW, 9, 10, 11, 12, 13, and Oea alleles were noted to be monomorphic only. HPA-3a/3b alleles had frequencies of 0.595/0.405, 0.505/0.495, 0.507/0.493, 0.530/0.470, while Gova/Govb of 0.462/0.538, 0.450/0.550, 0.463/0.537, 0.520/0.480 among Taiwanese, Indonesians, Thais and Filipinos respectively. The prevalence rates of HPA-1 to 13 in this study were also consistent with other previous reports using different methods. The alloimmunization due to Gov and HPA-3 antigens need to be emphasized in these populations.  相似文献   

15.
A Urzainqui  E Tabarés  L Carrasco 《Virology》1987,160(1):286-291
At least 74 acidic and 37 basic proteins are synthesized in African swine fever virus (ASFV)-infected monkey cells not detected in uninfected cells analyzed by two-dimensional gel electrophoresis. Essentially all the proteins synthesized early during infection are also observed at late times. The use of inhibitors such as cycloheximide and phosphonoacetate has led to the identification of 34 immediate early and 13 delayed early polypeptides. Therefore 64 proteins were classified as late polypeptides. Several ASFV-induced proteins are phosphorylated as proteins a1, a4, a20, a41, a48, a49, a51, a52, a55, a58, a67, b2, b12, b28, and b32.  相似文献   

16.
A long-term durability test was conducted on a newly developed axial-flow ventricular assist device (VAD) with hydrodynamic bearings. The mock circulatory loop consisted of a diaphragm pump with a mechanical heart valve, a reservoir, a compliance tank, a resistance valve, and flow paths made of polymer or titanium. The VAD was installed behind the diaphragm pump. The blood analog fluid was a saline solution with added glycerin at a temperature of 37 °C. A pulsatile flow was introduced into the VAD over a range of flow rates to realize a positive flow rate and a positive pressure head at a given impeller rotational speed, yielding a flow rate of 5 L/min and a pressure of 100 mmHg. Pulsatile flow conditions were achieved with the diastolic and systolic flow rates of ~0 and 9.5 L/min, respectively, and an average flow rate of ~5 L/min at a pulse rate of 72 bpm. The VAD operation was judged by not only the rotational speed of the impeller, but also the diastolic, systolic, and average flow rates and the average pressure head of the VAD. The conditions of the mock circulatory loop, including the pulse rate of the diaphragm pump, the fluid temperature, and the fluid viscosity were maintained. Eight VADs were tested with testing periods of 2 years, during which they were continuously in operation. The VAD performance factors, including the power consumption and the vibration characteristics, were kept almost constant. The long-term durability of the developed VAD was successfully demonstrated.  相似文献   

17.
Blastocystis has a widespread distribution in a variety of animals, which is a potential source of infection for humans. However, the contribution of zoonotic transmission remains unclear due to the absence of molecular proof of these organisms being identical to those found in humans. We report herein the similar subgroup of Blastocystis isolates from humans, pigs, and a horse using a restriction fragment length polymorphism (RFLP) analysis of partial small-subunit ribosomal DNA (ssu rDNA). Additionally, sequence and phylogenic analysis of partial ssu rDNA of Blastocystis from a human, a pig, and a horse sharing a common subgroup shows that Blastocystis isolates from a pig and a horse were monophyletic and closely related to B. hominis, with 92 to 94% identity. These results suggest the possibility of zoonotic potential of Blastocystis.  相似文献   

18.
A slide centrifuge Gram stain procedure was performed to screen for bacteriuria 4161 urine specimens submitted in urine preservative tubes for routine culture. For slide centrifuge Gram staining, each urine sample was mixed well. Thereafter, 0.2 mL of each sample was placed, using a pipette, into a slide centrifuge chamber and centrifuged at 2,000 rpm for 5 minutes. The slides were heat fixed, Gram stained, and read by laboratory personnel who scanned 12 consecutive oil-immersion fields using a set pattern. The presence of the same organism in six or more fields was defined as a positive urine screen. Urine samples were cultured using a 0.001-mL loop and a comparison of culture growth with slide centrifuge screening was made. When growth of 100,000 or more colony-forming units per milliliter (CFU/mL) was the reference for comparison, the screen had a sensitivity rate of 98%, a specificity rate of 90%, a negative predictive value of 99%, and a positive predictive value of 65%. When a lower colony count of 10,000 or more CFU/mL was the reference for comparison, the screen had a sensitivity rate of 88%, a specificity rate of 95%, a negative predictive value of 96%, and a positive predictive value of 84%. The slide centrifuge Gram stain is a very sensitive screening method to detect bacteriuria in an adult male population.  相似文献   

19.
Dolichospondylic dysplasia (DD) is a rare skeletal dysplasia primarily characterized by tall vertebral bodies and disproportionate short stature. Radiographic manifestations include tall vertebral bodies and gracile bones of the hands. Patients usually have eye and ear findings in addition to borderline mental retardation; however, tall vertebral bodies and slender tubular bones are also seen in the 3-M syndrome. Patients with the 3-M syndrome have a characteristic face with a triangular shape, frontal bossing, a flattened malar region, full eyebrows, a short nose with a bulbous tip, upturned nares, and full lips. We present two unrelated patients who share a distinct phenotype and have tall vertebral bodies, overtubulation of long bones, and short tubular bones of the hands and feet. We discuss the overlapping and distinguishing features between DD and the 3-M syndrome. Patient 1 was a 13-year-old female, and patient 2 was an unrelated adult female. These patients had normocephaly and short stature. They shared a common phenotype consisting of mild malar hypoplasia, a narrowed nasal body with a fleshy tip, full lips, and normal intelligence. In addition, they showed mild hand and foot abnormalities. These two patients lack many of the typical clinical features of both DD and the 3-M syndrome. They share a common phenotype and likely represent a distinct disorder. The spectrum of disorders with tall vertebral bodies as a key feature may include different entities that may be further defined with the characterization of the molecular defect(s).  相似文献   

20.
We report on sisters with similar craniofacial anomalies, a brain malformation in the area of the posterior fossa, and a congenital heart defect. The craniofacial findings include macrocephaly, a prominent forehead and occiput, foramina parietalia, hypertelorism, downslanting palpebral fissures, a depressed nasal bridge, narrow palate, and apparently low-set ears. Patient 1 had a Dandy-Walker malformation with communicating hydrocephalus, aplasia of the posterior portion of the cerebellar vermis, and high insertion of the confluent sinus, while in patient 2, a Dandy-Walker variant was found with aplasia of the cerebellar vermis and hypoplasia of the hemispheres, large cisterna magna, high insertion of the confluent sinus, but no hydrocephalus. Both sibs were moderately mentally retarded. The older sister had a complete atrio-ventricular canal and died after unsuccessful heart operation at 3 1/2 years. The younger had a successful operation on a cleft mitral valve and septum primum defect. Chromosomes were normal. The occurrence of a distinct and similar pattern of congenital anomalies in sisters born to healthy parents points toward a "new" syndrome caused by the homozygous state of an autosomal recessive gene.  相似文献   

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