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101.
The serotonin (5HT3) antagonist ondansetron was compared in a randomised study with metoclopramide and dexamethasone for the prevention of chemotherapy induced emesis. Thirty children aged 1-15 years with acute lymphoblastic leukaemia received 'intensification modules' according to the MRC United Kingdom acute lymphoblastic leukaemia regimen UKALL XI. This contains the moderately emetogenic drugs daunorubicin, etoposide, and cytarabine. Fifteen children received an intravenous loading dose of ondansetron followed by intravenous or oral doses 12 hourly for five days. Fifteen children received intravenous metoclopramide every six hours for three days with a loading dose of dexamethasone, repeated every eight hours for three days intravenously or orally. Efficacy was assessed by a diary card documenting the incidence of nausea, retching, or vomiting. In the 24 hour period after starting chemotherapy, ondansetron was more effective, with a complete or major response rate of 93%, compared with 33% using metoclopramide/dexamethasone.  相似文献   
102.
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   
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105.
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   
106.
A study of 140 days duration was performed to examine if human male volunteers (n = 5) respond to ovine follicle stimulating hormone (oFSH) immunization (administered adsorbed on Alugel on days 1, 20, 40 and 70) by producing antibodies capable of both binding and neutralizing bioactivity of human FSH. The kinetics of antibody production for both the immunogen (oFSH) and the cross-reactive antigen (hFSH) were essentially similar. The volunteers responded only to the first two immunizations. The boosters given on days 40 and 70 were ineffective, probably because of the presence of substantial amounts of circulating antibody to oFSH. Of the antibodies generated to oFSH, 25-45% bound hFSH with a mean binding affinity of 0.65 x 10(9) +/- 0.53 M(-1). The binding capacities at the time of high (30-80 days of immunization) and low (>110 days) titres were 346 +/- 185 and 10.5 +/- 5.8 ng hFSH/ml respectively. During the period of high titre, free serum FSH (value in normal males 1-5 ng/ml) was not monitorable. A 50 microl aliquot of the antiserum obtained from different volunteers between days 30 and 80 and on day 140 blocked binding of (125)I-labelled hFSH to its receptor by 82 +/- 9.7 and 53 +/- 12.2% respectively. The antibody produced was specific for FSH, and no significant change in the values of related glycoprotein hormones (luteinizing hormone/testosterone and thyroid stimulating hormone/thyroxine) were recorded. Seminal plasma transferrin, a marker of Sertoli cell as well as of seminiferous tubular function, showed marked reduction (30-90%) following immunization with oFSH. Considering that endogenous FSH remained neutralized for approximately one sperm cycle only (65 days), the reduction in sperm counts (30-74%) exhibited by some volunteers is encouraging. Immunization with oFSH did not result in any significant changes in haematology, serum biochemistry or hormonal profiles. There was no production of antibodies capable of interacting with non- specific tissues. It is concluded that it should be possible to obtain a sustained long-term blockade of endogenous FSH action in men by using oFSH as an immunogen. This is a prerequisite for obtaining significant reduction in the quality and quantity of spermatozoa produced, thus leading to infertility.   相似文献   
107.
As genomic sequencing expands, so does our knowledge of the link between genetic variation and disease. Deeper catalogs of variant frequencies improve identification of benign variants, while sequencing affected individuals reveals disease‐associated variation. Accumulation of human genetic data thus makes reanalysis a means to maximize the benefits of clinical sequencing. We implemented pipelines to systematically reassess sequencing data from 494 individuals with developmental disability. Reanalysis yielded pathogenic or likely pathogenic (P/LP) variants that were not initially reported in 23 individuals, 6 described here, comprising a 16% increase in P/LP yield. We also downgraded 3 LP and 6 variants of uncertain significance (VUS) due to updated population frequency data. The likelihood of identifying a new P/LP variant increased over time, as ~22% of individuals who did not receive a P/LP variant at their original analysis subsequently did after 3 years. We show here that reanalysis and data sharing increase the diagnostic yield and accuracy of clinical sequencing.  相似文献   
108.
Almaguer‐Mederosa LE, Falcón NS, Almira YR, Zaldivar YG, Almarales DC, Góngora EM, Herrera MP, Batallán KE, Armiñán RR, Manresa MV, Cruz GS, Laffita‐Mesa J, Cyuz TM, Chang V, Auburger G, Gispert S, Pérez LV. Estimation of the age at onset in spinocerebellar ataxia type 2 Cuban patients by survival analysis. Previous studies have investigated the close association that exists between CAG repeat number and the age at onset in SCA2 = spinocerebellar ataxia type 2. These studies have focused on affected individuals. To further characterize this association and estimate the risk of a carrier developing SCA2 at a particular age as a function of a specific CAG repeat size, we have analyzed a large group of 924 individuals, including 394 presymptomatic and 530 affected individuals with a CAG repeat length of 32–79 units. Using a Kaplan–Meier survival analysis, we obtained cumulative probability curves for disease manifestation at a particular age for each CAG repeat length in the 34–45 range. These curves were significantly different (p < 0.001) and showed small overlap. All these information may be very valuable in predictive‐testing programs, in the planning of studies for the identification of other genetic and environmental factors as modifiers of age at onset, and in the design of clinical trials for people at enlarged risk for SCA2.  相似文献   
109.
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   
110.
目的:评价多沙唑嗪治疗高血压的临床疗效和安全性。方法:采用双盲双模拟随机对照的方法观察多沙唑嗪的疗效和安全性。经过2周的清洗期,共有43例病人入选(试验组22例,对照组21例),按试验流程服药及监测血压、心率、肝肾功能及心电图等指标。结果:经过临床6周的药物治疗,临床有效率达86.4%,其中显效率为68.2%,对肝肾功能无影响,无严重不良反应。结论:多沙唑嗪是一种有效、安全的治疗轻、中度高血压的药物。  相似文献   
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