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11.
人尿中几种雄激素及蛋白同化激素的HPLC测定   总被引:3,自引:0,他引:3  
毕红钢  周同惠 《药学学报》1989,24(3):207-211
对HPLC分离及定量测定人尿中雄激素及蛋白同化激素的方法进行了初步研究。确定了六种甾体激素的分离条件及内标定量方法。固定相为C8键合硅胶,甲醇—乙腈—水(4:5:6)恒溶剂洗脱,程序流速。紫外检测器波长254 nm。检测限可至1 ng以下。本法采用Sep-Pak C18小柱进行尿样净化,回收率高而且稳定。操作简便快速。对尿样中甾体葡萄糖醛酸甙结合物的酶促水解条件也进行了初步探索。  相似文献   
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Aim: To test the hypothesis that levels of sperm disomy fell significantly in six men treated by traditional Chinese medicine (TCM). Methods: Fluorescence in situ hybridization (FISH) was done on the sperm heads of six men before and during treatment by TCM. Results: There was a significant reduction in sperm disomy in all six men. This coincided with TCM treatment. Conclusion: This is the first study reporting a significant reduction in sperm disomy in men over a given time course. The fact that this coincided with TCM treatment is intriguing but no conclusions can be drawn from this until placebo-controlled clinical trials are implemented.  相似文献   
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A prototype ultrafast cine computed tomographic (CT) scanner, designed specifically for cardiac imaging, was used to evaluate a preliminary series of patients with prior myocardial infarction (n = 21) and a control group without coronary artery disease (n = 5). Multilevel 50-msec CT scan exposures were obtained during peripheral intravenous bolus injections of contrast medium. A comparison was made between cine-CT scans and standard left ventriculographic images in assessing segmental left ventricular motion. Results indicate that cine CT, performed at sufficiently rapid speeds (20 scans per second) to allow useful analysis of regional ventricular wall motion, can provide adequate image quality. Analysis of 110 segments revealed a good correlation (90.9%) between the two techniques in characterizing normal from abnormal regional wall motion. Cine CT, based on this initial study, demonstrates considerable potential for evaluating not only cardiac chamber dimensions but also segmental wall dynamics.  相似文献   
16.
1. There is evidence that different aetiologies of heart failure, especially ischaemic vs dilated cardiomyopathy (ICM and DCM, respectively), may influence the prognosis of patients with this disease. Patients with ICM have a worse prognosis than those with DCM; the mechanisms underlying this difference have not yet been clarified. The aim of the present study was to investigate whether there are changes in myofibrillar function depending on the aetiology of human heart failure. 2. Ca2+‐dependent tension (DT) and actomyosin ATPase acitivity (MYO) in Triton X‐skinned fibre preparations of the left ventricular myocardium from patients with heart failure due to ICM (n = 5) and DCM (n = 5) were measured. Tension‐dependent ATP consumption was calculated by the ratio of DT and MYO (‘tension cost’). Non‐failing myocardium (NF) from donor hearts, which could not be transplanted because of technical reasons, was evaluated as a control. 3. Although DT was reduced, the myofibrillar Ca2+ sensitivity of DT and MYO, as well as tension cost, were increased in preparations from ICM and DCM myocardium compared with NF. The Ca2+ sensitivity of DT and MYO was significantly increased in ICM compared with DCM preparations, resulting in more economic cross‐bridge cycling in ICM than in DCM. 4. In conclusion, ICM is associated with an increased Ca2+ sensitivity of myofibrillar tension and ATPase activity accompanied by decreased tension cost compared with DCM. Thus, the worse prognosis associated with ICM does not seem to be due to differences in myofibrillar function.  相似文献   
17.
EM Sloand  ; HG Klein 《Transfusion》1990,30(4):333-338
White cells (WBCs) present in stored platelet concentrates have adverse effects on platelet function and on posttransfusion recovery. Although these effects have been attributed to the fall in pH that results from active WBC metabolism, platelets stored in gas-permeable storage bags still exhibit abnormalities, despite maintenance of a stable pH of greater than 6.0. The changes in platelet proteins and function brought about by storage with a controlled number of WBCs were studied. Twelve platelet-pheresis specimens were centrifuged at 180 x g to achieve a WBC count of less than 2 x 10(5) per mL (which contained less than 10% granulocytes). These specimens were split into two aliquots and placed in platelet bags for storage at 22 degrees C with constant horizontal agitation. Neutrophils, obtained from the same donor by centrifugation of 50 mL of whole blood through a discontinuous ficoll gradient, were added to one of the two platelet storage bags to achieve a final neutrophil count of 1 x 10(6) per mL. Platelet aliquots were removed and studied on Days 3 and 5. In platelets stored without neutrophils, the average response to ristocetin, using the mean slope as an index of platelet responsiveness, was 10.3 (n = 9, SD = 11) on Day 3, whereas for the platelets stored with neutrophils, it was 1.25 (n = 12, SD = 0.9, p less than 0.01). Significant differences were also seen on Day 5 (slope = 4.5 for platelets stored without neutrophils, slope = 0.3 for platelets stored with neutrophils, p less than 0.01). Platelet aggregation with 8 microM ADP and 1.5 mg per mL of collagen did not differ significantly.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
18.
白介素与溃疡性结肠炎   总被引:17,自引:1,他引:17  
近年来对白介素(interleukin,IL)和溃疡性结肠炎(ulcerative colitis,UC)的研究取得了很大进展,我们通过总结整理以前有关IL和UC的文献,概括出IL的产生和在UC发病及病理变化中的作用机制:IL-1直接介导了UC初期阶段炎症的发生:IL-8、IL-6直接促进炎性细胞过度分泌和/或抑制了炎性细胞的凋亡,IL-2分泌减少导致免疫系统内细胞间网络调节失衡, 使局部炎症介质和自由基释放,引起细胞毒作用,IL主要通过影响机体整体和/或局部免疫系统的功能介导UC的产生,并与UC的迁延难愈和反复发作有关.  相似文献   
19.
Effect of amphotericin B and fluconazole on platelet membrane glycoproteins   总被引:1,自引:0,他引:1  
BACKGROUND : Fever, chills, and reduced platelet recovery may result when platelets are transfused simultaneously with amphotericin B. Amphotericin B reportedly increases the pitting of membranes in stored platelets. STUDY DESIGN AND METHODS : The effects of amphotericin B and another antifungal agent, fluconazole, on platelet membrane glycoproteins (GP) were examined by the incubation of split aliquots of fresh and stored platelet concentrates (PCs) with these drugs for 3 days in storage bags. To determine the effect of storage, PCs were stored for 5 days, and aliquots removed on Days 1 through 5 were placed in platelet storage bags with 4 micrograms per mL of amphotericin B for 2 to 6 hours. Membrane glycoprotein expression was assessed by flow cytometry with fluorescein isothiocyanate-labeled monoclonal antibodies (MoAbs) directed against the following antigens: GPIb (CD42b), CD63 (an activation protein), P-selectin (CD62), and GPIIb/IIIa (CD41a). RESULTS : Amphotericin B produced a concentration-dependent decrease in the surface binding of CD42b MoAb with no consistent changes in the binding of CD41a, CD63, or CD62 MoAbs after a 3-day exposure. Stored but not fresh PCs showed decreased binding of MoAb CD42b after a 6-hour exposure to amphotericin B (4 micrograms/mL). Fluconazole produced no changes. When the binding of MoAb CD42b to permeabilized platelets was used to measure total platelet content, amphotericin B (4 micrograms/mL) decreased MoAb CD42b binding to a similar degree in fresh and stored platelets. Inhibition of aggregation to ADP and collagen and ADP and epinephrine was seen in stored but not fresh PCs. CONCLUSION : Therapeutic levels of amphotericin B resulted in partial loss of total platelet GPIb in fresh and stored PCs, but decreased surface expression of platelet membrane GPIb only in stored platelets. This difference between fresh and stored platelets may be related to the limited reservoir of GPIb available for redistribution to the membrane in the previously stored PCs and may account for the decreased recovery of transfused platelets observed in some patients receiving amphotericin B.  相似文献   
20.
Aim.?To study psychological well-being (health-related quality of life) in a population of adults 20 years and over with hearing impairment (HI) and its relation to audiological factors, consequences of the HI, sense of humour, and use of communication strategies.

Subjects and methods.?Consecutive adults (n = 343) at the outpatient Unit of Audiology of a Norwegian university hospital answered the Psychological General Well-being inventory (PGWB), Hearing Disability and Handicap Scale (HDHS), Sense of Humour Questionnaire-6 (SHQ-6), and Communication Strategies Scale (CSS) in relation to an audiological examination and medical consultation.

Results.?Mean PGWB index for the whole sample was 81.4 (SD 14.3) and females reported a significantly lower psychological well-being. In multiple linear regression analyses well-being was negatively associated with high levels of activity limitation and participation restriction. PGWB index was positively associated with high sense of humour, but was neither explained by audiological factors nor use of communication strategies.

Conclusions.?Psychological well-being was associated with the outcome of a standard HI assessment of activity limitation and participation restriction, but not with degree of HI and use of communication strategies.  相似文献   
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