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991.
992.
In this work the effects of parathion (a competitive acetylcholinesterase inhibitory agent) on the enzyme activity was studied by cytochemical methods in the kidney of rats; being the doses used not inhibitory of red blood cells acetylcholinesterase (subtoxic dose). Two groups of rats were used: control (CR) and parathion-treated (TR) groups, both submitted to a water deprivation period of 24 h. for induction of primary thirst. The treated-rats group received parathion i.p. at doses of 600 micrograms/100g body weight. For demonstration of acetylcholinesterase activity, renal tissue incubation was performed by the Karnovsky and Roots method with the Tsuji Larabi variation. The results of the five assays of incubation enable us to conclude that there exists a noticeable activity of acetylcholinesterase in the renal cortex of control rats, which is blocked by subtoxic doses of organophosphorus pesticide. We suggest that the natriuretic effect of parathion can be explained by this mechanism. 相似文献
993.
BE Ley N Jalil J McIntosh A Smart M Wilson AB Foot MR Millar 《Canadian Metallurgical Quarterly》1996,38(6):1091-1095
An unexpected low efficacy of teicoplanin in the treatment of coagulase negative staphylococcal (CNS) infections on a regional Bone Marrow Transplant (BMT) Unit led to a retrospective study. CNS infections treated with gylcopeptides in BMT patients with in-dwelling central venous lines between May 1990 and May 1995 were reviewed. Efficacy rates of 50% for teicoplanin compared with 80% for vancomycin despite comparable antibiotic susceptibility. Glycopeptides have bactericidal action which is time dependent. Teicoplanin was administered by bolus injection during the study period and it is suggested that this observed difference in efficacy is caused by the short duration of exposure of luminal bacteria. 相似文献
994.
C Tschopp AB Safran P Viviani M Reicherts A Bullinger C Mermoud 《Canadian Metallurgical Quarterly》1998,38(14):2211-2218
We determined normative values for the visual sensitivity threshold in 118 children aged 5-8 years, using automated static perimetry (Octopus 2000R, program 32). In addition, 17 normal adults were tested. The children first underwent a familiarization procedure. One week later, quantitative examination was performed according to a specially designed schedule divided into three phases. For each of the 76 points tested, mean thresholds and standard deviations were calculated as a function of age. In contrast to previous studies, sensitivity difference between adults and children over the central 30 degrees of the visual field emerged only for the youngest age groups (5- and 6-year olds). Both the response rate in false-negative trials, and values of a within-subject threshold variability index, suggested that 5- and 6-year-olds' higher thresholds were inflated by non physiological factors, such as vigilance and cognitive processes. For these ages, the data reported here should therefore be considered as an approximation of the upper level of the thresholds. In contrast, our results for 7- and 8 year-old children provided reliable normative values for light sensitivity across the visual field. 相似文献
995.
A 46-year-old women presented with an inoperable low-grade endometrial stromal sarcoma. Two doses of Depo-Lupron, 7.5 mg, and Megace, 160 mg/day, were given to control uterine bleeding and shrink the tumor mass. In 9 weeks, significant reduction in the tumor occurred allowing for surgical resection. Total abdominal hysterectomy with bilateral salpingo-oophorectomy is the mainstay for primary treatment. The role of chemotherapy, radiation therapy, and hormonal therapy is poorly defined. This is a case report of neoadjuvant hormonal therapy which may improve outcomes in patients with endometrial stromal sarcomas. Additional research is needed to define the exact role of these agents. 相似文献
996.
CD23, the low-affinity IgE receptor, is believed to participate in immune responses by mediating antigen capture for presentation by B cells and by shedding fragments with immunomodulatory properties. The number of CD23 molecules on B cells is increased during allergic responses and infection with helminths. This can be attributed in part to regulation of CD23 expression by cytokines, including IL-4. In addition, there is evidence that CD23 can be induced on cultured B cells by its ligand, IgE. In the current study we use IgE-deficient (IgE-/-) mice to establish the effects of IgE on CD23 expression by B cells in vivo, in the absence of allergic or parasitic stimuli. The spleens of IgE-/- and wild-type mice contained similar proportions of CD23+ B lymphocytes. However, cells from IgE-/- mice were found to have nearly 3-fold less CD23 on their surface. The mutant B cells had a corresponding defect in their ability to bind IgE. CD23 could be normally induced on IgE-/- B cells after culture with IL-4 or CD40 ligand, indicating that these cells had no inherent defect in CD23 biosynthesis. CD23 expression and IgE-binding capacity were both restored when splenocytes from IgE-/- mice were cultured in the presence of IgE. IgE-induced up-regulation of CD23 could be elicited in vivo as well. In IgE-/- mice, i.v. infusion of IgE corrected CD23 expression to wild-type levels. Our results demonstrate that IgE directly participates in CD23 regulation in vivo. This positive feedback loop may constitute a mechanism for the amplification of ongoing allergic responses. 相似文献
997.
998.
The aim of this study was to integrate both dispositional and situational factors to examine their interactive ability to predict pre-competitive goal states of task and ego involvement in a sample of National junior tennis players. The Task and Ego Orientation in Sport Questionnaire (Chi and Duda, 1995) and a set of single-item assessments of match goal orientation represented the dispositional measures in the study. These were administered at home, away from the tennis environment. The situational antecedents of pre-match task and ego involvement were assessed by an 11-item Match Context Questionnaire, which was administered to the players (n = 119) within 1 h of their singles match start time at the National Junior Championships. The Match Context Questionnaire also measured the personal task- and ego-involved goal states of the player with respect to the upcoming singles match (i.e. 'state' goals). Factor analysis of this questionnaire revealed three situational factors which cumulatively accounted for 64.7% of variance in the match context: social/personal perceptions of ability; perceived state goal preference of significant others; and match value. Moderated hierarchical regression analyses revealed significant main effects of the dispositional and situational factors on the different goal types. Specifically, perceptions of significant others, the achievement value of the match and perceptions of ability were the major predictors of task involvement. The pre-match intensity of ego involvement was predicted by ego orientation combining with perceptions of significant others and match value. These findings reinforce the need for researchers to consider the importance of both dispositional and situational variables when predicting goal involvement in competitive contexts. 相似文献
999.
D Kassimos EH Choy AB Grossman IC Chikanza GS Panayi 《Canadian Metallurgical Quarterly》1996,35(5):436-440
A monoclonal antibody giving a dominant reaction with the group-specific polysaccharide of streptococcus group B in an ELISA test has been developed. The purified polysaccharide exhibited a high positivity with reference anti B streptococcal antiserum in the ELISA test. Cross-tests of antibodies with other groups of streptococci provided a minimum cross-reaction only in the case of G streptococci. Monoclonal antibodies were prepared using Streptococcus agalactiae S 589 MT strain isolated from a case of bovine mastitis which does not express Ia, Ib, II, III, IV and V type antigens, nor C, R and X protein antigens. 相似文献
1000.
The three-dimensional video analysis of human motion commonly utilises automated image processing and digitisation processes to produce real-time unidentified two-dimensional coordinate data of segmental markers. In what can be a time-consuming process the two-dimensional data are then identified and tracked to produce three-dimensional coordinates. This paper presents an approach to the automated reproduction of three-dimensional coordinates from two-dimensional coordinates data. Conjugate imaging techniques were utilised in the development of four criterion measures for determining the validity of conjugate (corresponding) image points. An algorithm based on the criterion measures was then developed for the automated reproduction of three dimensional coordinates from camera image coordinate data. The algorithm was tested with a 55 point marker system viewed in four video cameras (digitisation error approx. 0.2%, lab point separation > or = 6 cm). The success of the algorithm was dependent on the closeness of markers, the accuracy of the photogrammetric system, and the number of markers visible in two camera images. The present research has developed techniques based on conjugate imagery for the automated reproduction of three-dimensional coordinates from two-dimensional data, and provided a bases for further development of automated three-dimensional tracking. 相似文献