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1.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence.  相似文献   
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Isolated sperm from normo-, oligo- and astheno-spermic men were incubated for 20 h in medium supplemented with 8% heat-inactivated or untreated human serum, and in medium with heated or untreated serum deficient in complement factor C3. Before and after incubation, sperm motility was assessed by means of a computer-assisted semen analyser. The results did not show significant differences between the motility of sperm incubated in heated or untreated serum. It is concluded that heating of homologous serum is not necessary for preserving sperm motility and in some cases may even be disadvantageous.  相似文献   
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Free erythrocyte protoporphyrin (FEP) and hemoglobin (Hgb) concentrations were tested in 790 children in a private pediatric office; results were compared to those obtained in 1984. Only 16 children (2%) had abnormal FEPs in 1990 compared to 76 children (9.6%) in the earlier study. The mean FEP in the normal group also decreased significantly in each age group studied. The hemoglobin concentrations were not significantly different in most of the age groups studied. Screening for iron deficiency in our pediatric practice by determining hemoglobin and FEP concentrations had a much lower yield in 1990 than in 1984.  相似文献   
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Image-directed percutaneous biopsies with a biopsy gun   总被引:3,自引:0,他引:3  
Core tissue for histologic study is believed by many pathologists to be more diagnostic than material from needle aspiration. Recently, a biopsy "gun" has been introduced, which simplifies core biopsies. With this device, 182 biopsies of multiple anatomic sites were performed with ultrasonic, computed tomographic, and fluoroscopic guidance and 18-gauge needles. High-quality histopathologic specimens were obtained in 177 of the biopsies, and diagnostic target tissue was obtained in 167. Only three significant complications occurred: one bleeding complication that required transfusion and two cases of pneumothorax that necessitated placement of chest tubes. The biopsy gun eliminated the disjointed movements of conventional "skinny" needle biopsies, and none of the samples demonstrated significant "crush" artifact or obscuring blood, problems that are commonly associated with manual biopsy techniques. Patient discomfort was decreased with this system compared with that of manual biopsies, and the total procedure time was reduced. Because of these distinct advantages, the authors now use the biopsy gun exclusively for all percutaneous biopsies and recommend that other institutions consider the use of this biopsy method.  相似文献   
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This study investigated the relationship of daytime sleepiness and performance on a vigilance test in a sample of 10 healthy men and 13 women in their 80s (mean age 83.0 +/- 3.1 years) and 18 men and 12 women in their 20s (25.0 +/- 3.1). We hypothesized that "successfully" aged healthy individuals would have more daytime sleepiness with differentially greater decrements in performance than a younger comparison group. Daytime sleepiness was measured physiologically by the Multiple Sleep Latency Test (MSLT) and through self-report by the Stanford Sleepiness Scale (SSS). Morning and evening performance was measured with the Mackworth Clock Test of vigilance. The major findings were the absence of correlation between either MSLT or SSS daytime sleepiness with performance measures, no difference in daytime sleepiness between the old and young groups and performance decrements among the healthy elderly on all parameters. Results suggest that the modest decrements in performance among the elderly cannot be attributed to daytime sleepiness.  相似文献   
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When plated in semi-solid media, PHA-stimulated human peripheral blood mononuclear cells (PBMC) form discrete T-cell colonies. By contrast, Sephadex G-10 non-adherent (NA) cells (greater than 96% T lymphocytes) show virtually no clonal growth unless cocultured with soluble factors derived from either normal adherent cells or tumour cell lines. Purified IL-1 was able to initiate colony growth of mitogen-stimulated NA cells; cultures containing 20 U of human IL-1 yielded colony counts that were only slightly less than those with PBMC. In addition, recombinant IL-2, free of measurable IL-1, was able to provide the initiating signal required for clonal expansion. Both recombinant and lymphocyte-derived IL-2 were able to enhance the clonal growth of PBMC. Colony growth could be initiated by supernatants derived from short-term cultures of either monocytic (U937, HL60) or B-cell (Raji, Daudi) tumour cell lines. The abilities of these tumour cell lines to promote clonal responses did not correlate with their contents of either IL-1 or IL-2. By contrast, supernatants derived from either K562 (an erythroleukaemic line) or MOLT 4 (a T-cell lymphoma) cells did not provide the initiating signal.  相似文献   
9.
目的观察去甲硫氨酸全肠外营养对大鼠血清氨基酸谱等的影响.方法 Wistar大鼠24只,随机分为含甲硫氨酸(+MetTPN,n=12)和去甲硫氨酸全肠外营养2组(-MetTPN,n=12),分别给予相应的TPN支持.治疗7d后,每组随机抽取6只大鼠处死,检测血清FAA(HPLC法)、肝肾功能和全血常规,同时作心、肺、肝、肾组织病理学检查.两组其余大鼠继续原TPN治疗,观察生存期.结果 -MetTPN组大鼠血清游离Met、Cys明显降低,Asp、Glu、Ser等显著增高;大鼠体重下降;血清总蛋白和白蛋白水平下降;血常规和肾功能未见明显异常;组织学检查见肝细胞轻度肿胀,细胞核仁增粗,心肺肾未见明显异常;平均生存18d.对照组上述检查未见异常,除一只大鼠因导管并发症于TPN第16d死亡,其余大鼠全部存活.结论 -MetTPN一周可致大鼠血清游离Met、Cys明显降低和Asp、Glu、Ser等显著增高,及轻度肝功能改变;随着-MetTPN时间延长,出现严重的代谢紊乱和器官功能障碍导致死亡.  相似文献   
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