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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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A statistical approach to the mechanical testing of dental materials   总被引:2,自引:0,他引:2  
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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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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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Giving chemotherapy and radiotherapy simultaneously (concomitant therapy) is one approach to improving results in advanced head and neck cancer. To assess the feasibility of one such regimen, 25 patients with advanced squamous carcinoma of the head and neck were treated with a continuous intravenous infusion of 5-fluorouracil, 1 g/m2 per 24 h for Days 1-5 (105 h) and mitomycin-C 14 mg/m2 intravenously on Day 3 during the first week of radiotherapy. Twenty had Stage IV disease; four Stage III; and one Stage II. Ages ranged from 21 to 73 years (median 60 years). The tumours involved were as follows: oral cavity (6); nasopharynx (8); oropharynx (5); secondary node from unknown primary (3); hypopharynx (2); paranasal sinus (1). Radiotherapy was delivered as 10 Gy per week (total dose 60-70 Gy). Chemotherapy was well tolerated and all received the intended dose. Mild nausea occurred in five patients and three experienced transient vomiting. A generalized "early" mucositis affected 16 out of 25 (64%), caused interruption of radiotherapy in three patients, and is thought to be chemotherapy related. Twenty-two patients received the dose of radiotherapy intended, and two stopped prematurely at 53 and 56 Gy. Three episodes of neutropaenic infection occurred. Two recovered uneventfully, but one toxic death occurred in a patient with alcoholic cirrhosis. A complete response was seen in 21 (84%). For 17 patients with non-nasopharyngeal carcinoma the 2-year survival is 40%, 24% disease free. The concomitant use of 5-fluorouracil, mitomycin and radiotherapy is well tolerated in this group of patients.  相似文献   
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