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91.
争光霉素A6和它在争光霉素复合物的地位   总被引:8,自引:0,他引:8  
争光霉素A5已鉴别为Bleomycin A6,在争光霉素复合物中所占比例一般在10%左右,在某些批样中可高达15%以上。文献报告Bleomycin A6在天然产的Bleomyein复合物中只有痕量。通过向发酵培养基中加入特定组分的末端胺可大大提高其特定组分在复合物中的含量比而其它组分的产生则不同程度地被抑制。但Bleomyein A6例外,即使向培养基中加入其末端胺精胺(0.3mg/ml),在所产生的复合物中大大增多的组分是Bleomyein A6,而Bleomycin A6仍只有痕量。这表明争光霉素产生菌有和Bleomycin产生菌明显不同的特点。  相似文献   
92.
93.
A survey for estimation of goitre in school children in the Rural Health Training Centre, Shirur area was undertaken. A total of 4664 students from 17 schools were surveyed. The goitre prevalence was found to be 59.8% with visible goitre rate of 6.2% in pre- and peri-adolescent (10–19 years) age group. Thus a highly endemic goitre focus was located in Shirur, area in Pune District (Maharashtra). This area is located on the eastern tail-end slopes of Sahyadri Hills in Balaghat ranges, situated at an altitude of 533 metres. The area is generally drought prone and receives scanty rain, with poor agricultural practices. Environmental deficiency of iodine was found to be the main cause for this high prevalence of goitre.KEY WORDS: Goitre endemic, Iodine  相似文献   
94.
Analysis of Rorschach response patterns of 30 adolescent schizophrenics and an equal number of age and sex matched normal adolescents was undertaken. Two of the five Thiesen''s patterns associated with schizophrenia, namely pattern C and D, occurred significantly more frequently in Rorschach responses of adolescent schizophrenics as compared to normal controls.KEY WORDS: Rorschach test, Schizophrenia  相似文献   
95.
Background Although eccrine poroma (EP) occurs preferentially in palmoplantar areas, pigmented variants of EP have not been documented on the palms and soles. Objectives We seek to confirm the notion regarding lack of pigmented EP on palmoplantar areas and determine whether the absence of pigmentation in palmoplantar EPs is due to lack of expression of melanocyte‐stimulating cytokines by tumour cells. Methods We searched the PubMed and Web of Science databases (1966–2006) for reports of pigmented EPs. In addition, a total of 17 EPs were collected from our pathology department. The presence of melanin was examined with haematoxylin‐eosin sections, and melanocyte colonization was shown by immunohistochemical stains for tyrosinase. In addition, immunohistochemical staining with antibodies to melanocyte‐stimulating cytokines, including endothelin‐1, stem cell factor, and nerve growth factor, was done on these tumours. Results A review of the literature revealed 15 pigmented EP reports, none of which were located in palmoplantar areas. Among 17 EPs collected from our pathology department, 7 occurred in palmoplantar areas and 10 in non‐palmoplantar areas. Three of the palmoplantar EPs and three of the non‐palmoplantar EPs showed positive staining with melanocyte‐stimulating cytokines. However, none of the palmoplantar EPs contained melanocytes or melanin pigment, wheras the three non‐palmoplantar EPs that stained positively with melanocyte‐stimulating cytokines were colonized with melanocytes and showed pigmentation clinically. Conclusions The expression of melanocyte‐stimulating factors by tumour cells is associated with melanocyte colonization in non‐palmoplantar EPs but not palmoplantar EPs. Therefore, the presence of melanocyte‐stimulating cytokines per se is not sufficient by itself to induce melanocyte colonization. Certain characteristics of palmoplantar skin, such as the dermal components of these anatomical sites, may play a role in inhibiting melanocyte colonization of EPs.  相似文献   
96.
Objective  To quantify participants' experiences of obtaining and giving information about disorders of sex development (DSD).
Design  Cross-sectional survey study that asked people about their current and past experiences relating to DSD disclosure.
Setting  A large tertiary referral centre for DSD management in the UK.
Population  One hundred of 126 people with a confirmed diagnosis of DSD who were invited to participate in the study formed the usable sample.
Methods  All people who attended clinic for follow-up during the study period and members of a patient support group whose annual meeting fell within the study period were asked to complete the Middlesex Communication Survey.
Main outcome measures  The Middlesex Communication Survey.
Results  Younger participants were more likely to report having been appropriately informed about their diagnosis than older people. Nearly half of the former had been fully informed about their diagnosis by age 15 years, compared with 0% of the older age group. In terms of information sharing, mothers were most likely to be the person with whom the participant had shared (almost/all) DSD information (74%), followed by current partners (71%). Information relating to genital surgery, presence of testes and clitoral anomalies were the least likely aspects to have been unambiguously shared with even the most informed person.
Conclusions  Our results suggest that difficulties in obtaining DSD information from care providers were common, and that communication has improved for younger participants. The study also confirmed that many people with DSD continue to struggle with confiding, even in those closest to them, about aspects of their diagnosis. Care protocol needs to centralise psychological adaptation, which should also be a primary focus for future research.  相似文献   
97.
目的:探讨瞬时性受体电位通道香草酸受体5、6与骨代谢的关系。资料来源:应用计算机检索PubMed数据库1999-01/2006-07相关瞬时性受体电位通道方面的文献,检索词“TRPV”,限定文献语言种类为English。资料选择:对资料进行初审,选取包括瞬时性受体电位通道香草酸受体5、6的文献,开始查找全文。纳入标准:对两者及瞬时性受体电位通道家族进行研究的文章。排除标准:研究内容局限于瞬时性受体电位通道香草酸受体1~4的文章。资料提炼:共检索到106篇关于瞬时性受体电位通道香草酸受体的文献,最终纳入30篇符合标准的文献。资料综合:瞬时性受体电位通道香草酸受体5、6是瞬时性受体电位通道超家族中的成员,是专门的上皮样钙离子通道。目前研究已经证明它们在肠道和肾脏等组织中有表达,并对跨细胞钙离子转运起着关键性调控作用。但在骨组织中表达情况相关报道较少,在骨代谢机制上的研究更少,本文针对目前两者与骨代谢的关系进行综述。结论:深入研究瞬时性受体电位通道香草酸受体5、6钙离子通道在骨代谢中的作用,对于那些与骨代谢相关疾病的治疗将能从分子水平上找到解决的方法。  相似文献   
98.
Blood transfusion costs: a multicenter study   总被引:5,自引:0,他引:5  
The cost of delivering a unit of blood (whole blood or red cells) to a hospitalized patient was examined in 19 United States teaching hospitals. The average hospital acquisition cost was calculated by using the prices charged by regional blood centers for blood products. To this cost was added an estimate of costs incurred by hospitals for handling, testing, and administering blood. Across study sites, the average hospital cost per unit transfused was $155 and the average charge to the patient was $219. Acquisition cost, the price that hospitals pay for blood, was 37 percent of the total cost to the hospital; the other 63 percent of the hospital cost included costs for blood bank handling (13%), laboratory tests (43%), and blood administration (7%). Significant variations in blood transfusion cost were found within our sample. Most of the variability can be attributed to geographic location of the blood supply source, type of red cell product transfused, prices charged by blood transfusion services, and the frequency of laboratory tests. The results of this transfusion cost study may be helpful in determining the costs of health care delivery, especially when blood transfusions are indicated.  相似文献   
99.
Weinberg  DS; Ault  KA; Pinkus  GS 《Blood》1988,72(2):698-704
A significant number of patients with non-Hodgkin's lymphoma have peripheral blood involvement during the course of their disease. Because the expression of receptor for the lectin peanut agglutinin PNA by normal lymphocytes is associated with noncirculating (stationary phase) cells, we studied the relationship between PNA binding by lymphoma cells and the presence of clonal B cells in the blood of 38 patients with B-cell lymphoma. The binding of PNA by cells in tissues was determined by the immunoperoxidase method and by two-color flow cytometry. Circulating lymphoma cells (clonal B cells) were identified by a sensitive flow-cytometric technique (kappa-lambda analysis) and were also studied for PNA binding in some cases. In all, 16 of 38 (42%) of lymphomas were PNA+, including a spectrum of histologic types. Circulating lymphoma cells were demonstrated in 17 of 22 PNA-lymphomas, whereas only 3 of 16 of PNA+ lymphomas had such circulating cells. Thus, there is a significant association between PNA binding and peripheral blood involvement by lymphoma (P less than .005 by chi- square analysis). In 12 cases, the circulating and tissue lymphoma cells had similar expression of PNA receptor (2 PNA+ and 10 PNA- cases), indicating that modulation of the PNA binding sites did not occur. In three patients who presented with lymphosarcoma cell leukemia, the circulating malignant cells were PNA-. These findings suggest that for both normal and malignant lymphocytes the absence of binding sites for PNA is associated with the capacity of these cells to circulate freely.  相似文献   
100.
A population of macrophage progenitor cells, with high proliferative potential, has recently been demonstrated in postfluorouracil-treated and normal mouse bone marrow (BM) in vitro, when the newly discovered growth factor (synergistic activity, SA) is combined with a macrophage colony-stimulating factor (CSF) as a proliferative stimulus. SA, shown to be present in human spleen and placental conditioned media (HSCM and HPCM, respectively) have been studied and found to be unstable to trypsin digestion and to heating at 50 degrees C or above; stable between pH 4 and 9; nonadherent to Con-A-Sepharose; and to have an isoelectric point between pH 5 and 5.8 and a molecular weight of between 14,000 and 21,000 as indicated by gel filtration chromatography. SAs from both HSCM and HPCM have been purified 89- and 122-fold, respectively, by precipitation of extraneous proteins at pH 5 followed by chromatographing twice on Sephacryl S200. Neither of these partially purified SAs contain any CSF for mouse BM. These results indicate that the SAs from HSCM and HPCM may be closely related and that they are structurally different from CSFs derived from various murine sources that have been shown to be stable to proteolytic enzymes and heat.  相似文献   
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