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21.
Two systems allowing quantitative, objective analysis of sperm movement were compared: 1) the Hamilton-Thorn Motility Analyzer (HTM), in which sperm images are digitized automatically, and 2) the Image-80, a modified image-analysis system in which sperm movement is digitized manually by hand tracing from videotape (Tessler and Olds-Clarke, 1985). Videotapes were made of human spermatozoa obtained by a swim-up procedure. The same videotape frames were analyzed by both systems. The mean percentage of motile spermatozoa was similar as judged by eye with either the HTM or Image-80 monitors and as reported by the HTM. For every motile spermatozoon, two motility parameters were calculated: linearity (a measure of track shape) and curvilinear velocity at 30 frames/second (a measure of track speed). When samples from five donors were averaged, there were no significant differences in mean linearity between automatic and manual systems. Also, linearity as reported by the HTM and Image-80 systems for the same track was significantly correlated (r = 0.72; N = 80). Whereas the absolute values for curvilinear velocity were slightly but significantly higher for the Image-80 system than for the HTM system, their correlation was also significant (r = 0.91). Since the two systems provide comparable data on percentage of motile sperm as well as speed and path shape parameters, this suggests that the HTM automatic digitization is accurate for images of human spermatozoa.  相似文献   
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This study tested 3 forms of alcohol risk reduction programming for young adults. Volunteers were randomly assigned to receive a 6-week class and discussion group, a 6-unit self-help manual, or a single 1-hr feedback and advice session with professional staff. Results reveal significant reductions in self-reported drinking at the end of the intervention phase and maintenance of drinking changes throughout a 2-year follow-up period. Comparable drinking reductions were rated across treatments; however, noncompliance with the self-help reading program suggested limited utility. Treatment response was related to subject age, as subjects showed increased drinking during the year they reached legal drinking status. The efficacy of brief motivational interventions and client matching in prevention programs is discussed.  相似文献   
24.
Five of 29 obsessive-compulsive disorder patients were dexamethasone suppression test (DST) nonsuppressors, all of whom met standard Hamilton Depression Rating scale criteria for at least mild depression. None of 24 nondepressed obsessive-compulsive disorder patients had an abnormal DST. The relationship of the DST to specificity of psychiatric diagnoses is discussed.  相似文献   
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Policosanol is a new cholesterol-lowering drug isolated and purified from sugar-cane wax. which prevents the development of lipofundin-induced lesions and foam-cell formation in New Zealand rabbits and Wistar rats. This study was conducted to examine the effects of policosanol on foam-cell formation in carrageenan-induced granulomas in rats. Eighteen Wistar rats were randomly distributed in three experimental groups which received orally for 20 days Tween 20 H2O as vehicle (control group) or policosanol at 2.5 or 25 mg kg?1. At the 11th day. lipofundin was injected intrapcritoneally for 8 days to induce formation of foam cells in the granuloma. At day 13, carrageenan was injected subcutaneously for granuloma induction and seven days later animals were killed. A significant reduction of the foam-cell formation in granulomas of policosanol-treated rats was observed. It is concluded that policosanol prevents the development of foam cells in carrageenan-induced granulomas (extravascular medium) in rats.  相似文献   
27.
Twelve Sardinian patients affected by histologically defined classic Kaposi's sarcoma (KS) were HLA-A, B, C and DR typed. Compared to 220 age and ethnically matched healthy controls, KS patients showed a significant increase in HLA-DR5 (66.6 vs 23.1%, P less than 0.001) and a considerable decrease in HLA-DR3 (8.3 vs 53.6%, P = 0.0055). No definite association was observed for other HLA antigens. These results confirm the existence of an HLA associated genetic control of KS susceptibility and support the hypothesis that HLA-DR5 plays the role of a predisposition marker while HLA-DR3 bears a genetic resistance to the disease.  相似文献   
28.
Endocannabinoids acting on CB1 cannabinoid receptors are involved in short- and long-term depression of synaptic transmission. The aim of the present study was to determine which endocannabinoid, anandamide or 2-arachidonoylglycerol (2-AG), is involved in depolarization-induced suppression of inhibition (DSI) in the cerebellar cortex, which is the most widely studied form of short-term depression. Depolarization of Purkinje cells in the mouse cerebellum led to an increase in intracellular calcium concentration and to suppression of the inhibitory input to these neurons (i.e. DSI occurred). Orlistat and RHC80267, two blockers of sn -1-diacylglycerol lipase, the enzyme catalysing 2-AG formation, abolished DSI by acting downstream of calcium influx. In contrast, DSI occurred also in the presence of a phospholipase C inhibitor. Intact operation of the calcium-dependent messengers calmodulin and Ca2+–calmodulin-dependent protein kinase II were necessary for DSI. DSI was potentiated by an inhibitor of the main 2-AG-degrading enzyme, monoacylglycerol lipase. Interference with the anandamide metabolizing enzyme, fatty acid amide hydrolase, did not modify DSI. Thus, three kinds of observations identified 2-AG as the endocannabinoid involved in DSI in the mouse cerebellum: DSI was abolished by diacylglycerol lipase inhibitors; DSI was potentiated by a monoglyceride lipase inhibitor; and DSI was not changed by an inhibitor of fatty acid amide hydrolase. Further experiments indicated that 2-AG is the endocannabinoid mediating short-term retrograde signalling also at other synapses: orlistat abolished DSI in the rat cerebellum, DSI in the mouse substantia nigra pars reticulata and depolarization-induced suppression of excitation in the mouse cerebellum.  相似文献   
29.
In 1942, Jaffe and Lichtenstein introduced the term aneurysmal bone cyst (ABC). Primary ABC is characterized by the presence of spongy or multi-cameral cystic tissue filled with blood. The process is benign, but it is locally destructive and has a high propensity for recurrence. In this paper, we present the third case of multiple metachronous primary ABCs as a rare variant of ABC. We describe the 10-year history of a 12-year-old boy with metachronous multiple primary ABCs at five different sites (right proximal humerus, right ulna, bilateral distal radius and right lateral clavicle). Furthermore, our patient suffered from vascular malformations, such as aortic isthmus stenosis, hypoplastic thoraco-abdominal aorta and bilateral renal artery stenosis. To date, in contrast to solitary ABC, the multiple lesions have been found more frequently in male individuals. Using interphase cytogenetics, we analyzed three of five of the patients ABCs and one of these was also analyzed by GTG-banding. No chromosomal abnormalities were found. Significantly, we excluded the missense mutation of codon 201 in guanine nucleotide-binding protein 1 gene consistently found in McCune-Albright syndrome (MAS) and in non-MAS cases of polyostotic fibrous dysplasia of bone with or without secondary ABC.  相似文献   
30.
This study examined alcohol use among seventh graders in relation to life events, daily hassles, the supportive quality of the family environment, coping, and anxiety. Four hundred twenty-five students participated, 228 girls and 197 boys. Stepwise regression and discriminant function analyses indicated that the students reported more alcohol use if they also reported more life events, more daily hassles, and more conflict in the family. A stress-buffering effect of low family conflict on life events could not be substantiated for extent of alcohol use. The results are discussed in the context of the developmental transitions of adolescence.  相似文献   
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