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排序方式: 共有271条查询结果,搜索用时 15 毫秒
1.
The inhibitory effect of polysaccharide on mumps virus multiplication   总被引:12,自引:12,他引:0  
Polysaccharides derived from type-specific Friedl?nder bacilli cause inhibition of the multiplication of mumps virus in the allantoic sac of the chick embryo. As little as 5 microg. of polysaccharide is effective as an inhibitor. Inhibition of multiplication is obtained when polysaccharide is injected as long as 4 days after inoculation of virus. Chemical studies have shown that the structural configurations of the polysaccharide responsible for specific serological activity are not identical with those which determine the inhibitory effect relative to mumps virus. The possible mechanisms of the inhibition of viral multiplication by means of polysaccharides are discussed.  相似文献   
2.
The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control.  相似文献   
3.
Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant.  相似文献   
4.
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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目的研究转录调控蛋白PrfA对两组新近发现的单核细胞增生李斯特菌基因的体外转录作用。方法利用本室近年来建立的体外转录系统,对两组基于转录基因组体内研究发现的5个可能的受PrfA不同调节的单核细胞增生李斯特菌基因进行了体外转录活性的研究。结果第一组中的hpt基因的体外转录活性受PrfA正调节,而其它4个基因既不被PrfA正调节也不被负调节。结论除hpt基因外,其它4个基因体外转录结果与体内实验不相一致,说明PrfA在体内可能通过复杂多样的非直接方式、或者还需要一些目前未知的因子来调控这些新近发现的基因的表达。  相似文献   
7.
颅内蛛网膜囊肿34例   总被引:1,自引:1,他引:0  
陈旭  王文甫 《医学争鸣》2000,21(9):1075-1075
1 临床资料1.1 一般资料  1986 / 1997收治颅内蛛网膜囊肿 34(男 2 8,女 6 )例 .年龄 3~ 6 8岁 ,其中 16岁以下 17例 .有头部外伤史者 15例 ,无明显诱因者 19例 .病程 :2 m o~ 14a.头部外伤至发病时间 :7d~ 2 a. 34例中幕上 30例 ,幕下 4例 ,其中侧裂池 15例 .1.2 临床症状 表现头疼、头昏或伴呕吐、视力下降、视乳头水肿等颅内压增高的症状 18例 ,癫痫发作 7例 ,偏瘫 6例 ,行走不稳 2例 ,失语 1例 .1.3 辅助检查 本组 2 8例作 CT检查 ,6例行 MRI检查证实 .头颅 CT扫描特征 :脑实质外有一边界清楚的低密度病灶 ,CT值与脑脊液…  相似文献   
8.
OBJECTIVE: To assess the efficacy of a longer acting preparation of the gonadotrophin releasing hormone (GnRH) analogue goserelin (Zoladex LA, 10.8 mg) in 12 girls with central precocious or early puberty. METHODS: Two girls started treatment de novo; the remainder had been on suppressive treatment for a median duration of 1.5 (range, 0.2-5.6) years. Assessment comprising auxology, pubertal staging, and pelvic ultrasound examination was carried out at weeks 0, 4, 8, 10, and 12 (first cycle) and weeks 8, 10, and 12 (second cycle) to evaluate the required injection frequency. Thereafter, assessment was performed on the day of injection. Zoladex LA was given every 12 weeks unless pubertal progression occurred. RESULTS: Satisfactory control was achieved in eight patients using this regimen, and three patients required more frequent injections. One girl was removed from the study because of clinical progression and extreme mood swings. No serious adverse effects occurred. Mean height velocity during the study period was 4.5 cm/year (range, 3.1-6.6) compared with 6.5 cm/year (range, 3.8-9.6) before treatment in nine patients for whom data were available. CONCLUSIONS: Zoladex LA was effective in controlling precocious puberty in girls when given at intervals of 9-12 weeks and it is recommended that an initial assessment is made eight weeks after beginning treatment.  相似文献   
9.
Horne  MK d; Rosse  WF; Flickinger  EG; Saltzman  HA 《Blood》1975,45(3):365-375
The "early-labeled" peak (ELP) of 14CO excretion following injection of glycine-2-14C was used to study erythropoiesis in a patient with sideroblastic anemia and in four subjects with myeloproliferative disorders. The ELP was greatly enlarged in all patients, as compared with a normal volunteer. The contour of the peaks from the hematologically abnormal subjects suggested the presence of increased erythroid heme degradation. In the patient with sideroblastic anemia, all hours of the early peak were significantly reduced after transfusion. This was interpreted to mean that even the earliest or "nonerythroid" phase of the peak is influenced by erythropoietic activity, at least under conditions of erythropoietic stress.  相似文献   
10.
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