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61.
Reardon O. Olubayo Steve Mihok Eli Munyoki Leonard H. Otieno 《Parasitology research》1994,80(3):177-181
The pattern of infection inGlossina morsitans morsitans andG. m. centralis membrane-fed on eland, buffalo or goat blood mixed withTrypanosoma congolense orT. brucei was studied from day 1 to day 10. Tsetse were initially permissive vectors, with most flies harbouring infections of 104–105 parasites on day 3. However, after a second blood meal on day 3, flies cleared many infections withG. m. morsitans clearing more infections thanG. m. centralis. Infective feeds of goat blood consistently increased final infection rates by limiting the number of infections lost between days 3 and 6. In further experiments withG. m. morsitans only, this effect was replicated by feeding flies on erythrocytes but not on serum. These results suggest that compounds from some mammalian erythrocytes match the target specificity ofG. m. morsitans midgut lectins and, hence, have a protective effect on trypanosome establishment in the fly. 相似文献
62.
It is often useful in studies of intellectual disability to be able to stratify the sample in terms of intellectual level. However, this information is sometimes difficult to obtain, and can involve a great deal of time if full IQ assessments are performed. This study explores the accuracy with which IQ scores can be projected by multiple regression from adaptive behaviour scores provided by informants. Fifty-one people with moderate, severe or profound intellectual disability received IQ assessments using the Kaufman Assessment Battery, and adaptive behaviour assessments using the Adaptive Behavior Scales (ABS). Ninety percent of projected estimates differed by less than 30% from that estimated by the K-ABC. Mean percentage divergence between actual and predicted estimates of IQ for the 51 cases for which all data were available was 15.0%. Limitations of the technique are discussed. The actual coefficients for calculating IQ are given in tabular form. 相似文献
63.
64.
Steve Nelson CPA 《Administration and policy in mental health》1992,20(2):129-133
Some nonprofit mental health organizations are buying real estate in order to own service delivery sites and to provide housing for clients. Owning real estate generally requires long-term financing to conserve cash. This article explores tax exempt financing methods available to nonprofit mental health organizations. 相似文献
65.
I. C. Bennett A. Khan R. De Freitas M. A. Chaudary R. R. Millis 《ANZ journal of surgery》1992,62(8):628-633
Thirty cases of phyllodes tumour (cystosarcoma phyllodes) of the breast that presented to the Clinical Oncology Unit at Guy's Hospital were reviewed. Tumours were classified as benign, malignant or borderline according to the following histological criteria: mitotic rate, nuclear pleomorphism, stromal overgrowth and tumour margins. In 14 (46.5%) cases the tumours were considered histologically benign, in 11 (36.5%) malignant, and in five (17%) borderline. Recurrence was seen in a similar proportion of patients with tumours classified as benign (21 %) and malignant (18 %) according to histological criteria. Malignant lesions tended to recur earlier. Infiltrating tumour margins were noted in all patients and stromal overgrowth in all hut one in whom recurrence was observed. Risk of recurrence also appeared to he related to tumour size. Only one patient developed distant metastases and died of her disease. Because of treatment variation no conclusion can he made regarding optimal therapy but the importance of adequate clearance, either through wide excision or mastectomy, is emphasized for all phyllodes tumours irrespective of histological features. 相似文献
66.
The usual form of the Mantel–Haenszel test statistic assumes independent observations. This is inappropriate for data from a stratified multistage survey. Two alternative adjustments to the test statistic are developed to deal with this: (a) a modification of the effective sample size for each row of each table, using the design effects, extending a method proposed by Donald and Donner for familial aggregation studies; (b) a Taylor series approximation to the variance of the square root of the numerator of the Mantel-Haenszel statistic. Both methods are evaluated by application to both simulated and real data. The two methods perform equally well, and offer a considerable improvement over the unadjusted test statistic when observations from the same cluster are highly correlated. A simplified adjustment is also considered, as is the need for correction to the variance of the odds ratio estimator. 相似文献
67.
Regional haemodynamic effects of human and rat adrenomedullin in conscious rats. 总被引:6,自引:3,他引:3
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1. Male, Long Evans rats were chronically instrumented with pulsed Doppler flow probes and intravascular catheters to permit assessment of the regional haemodynamic responses to human and rat adrenomedullin, to compare the responses to human adrenomedullin to those of human alpha-CGRP in the absence and presence of the CGRP1-receptor antagonist, human alpha-CGRP [8-37], and to determine the involvement of nitric oxide (NO)-mediated mechanisms in the responses to human adrenomedullin, relative to human alpha-CGRP. 2. Human and rat adrenomedullin (0.3, 1, and 3 nmol kg-1, i.v.) caused dose-dependent hypotension and tachycardia, accompanied by increases in renal, mesenteric and hindquarters flows and vascular conductances. At the lowest dose only, the hypotensive and mesenteric vasodilator effects of rat adrenomedullin were significantly greater than those of human adrenomedullin. 3. Human alpha-CGRP at a dose of 1 nmol kg-1 caused hypotension, tachycardia and increases in hindquarters flow and vascular conductance, but reduction in renal and mesenteric flows, and only transient vasodilatations in these vascular beds. These effects were substantially inhibited by human alpha-CGRP [8-37] (100 nmol kg-1 min-1), but those of human adrenomedullin (1 nmol kg-1) were not; indeed, the mesenteric haemodynamic effects of the latter peptide were enhanced by the CGRP1-receptor antagonist. 4. In the presence of the NO synthase inhibitor, NG-nitro-L-arginine methyl ester (L-NAME, 183 nmol kg-1 min-1), there was only a slight, but significant, inhibition of the hindquarters hyperaemic vasodilator effect of human adrenomedullin, but not that of human alpha-CGRP.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
68.
69.
Vaccination of Lewis rats with temperature-sensitive mutants of Mycoplasma pulmonis: adoptive transfer of immunity by spleen cells but not by sera. 总被引:1,自引:1,他引:0
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Temperature-sensitive mutant vaccines protect rats against Mycoplasma pulmonis infection. The role of the humoral or cellular immune response in resistance to mycoplasma infection was investigated by adoptive-transfer experiments. Spleen cells from Lewis rats vaccinated but not challenged with wild-type organisms (vaccinated) and spleen cells from rats vaccinated (or not) and challenged were effective in preventing syngeneic recipients from developing respiratory disease. There was also a significant reduction in the incidence and number of challenging organisms in the respiratory system. In contrast, sera from the same donors had no detectable effect on the number of mycoplasmas recovered or on lesion development in the respiratory tract. We conclude that cellular immunity rather than humoral immunity generated in vaccinated rats confers protection against subsequent infection. 相似文献
70.
Douglas M. Silverstein Ira Greifer Vaughn Folkert Boyce Bennett Howard E. Corey Adrian Spitzer 《Pediatric nephrology (Berlin, Germany)》1994,8(6):752-753
We report a patient who developed Henoch-Schönlein purpura (HSP) 13 years after he presented with IgA nephropathy (IgAN). In both HSP and IgAN renal biopsy most commonly reveals focal proliferative glomerulonephritis on light microscopy and immunofluorescence displays mesangial IgA deposits. In addition, patients with HSP or IgAN have elevated serum IgA levels, circulating IgA immune complexes, IgA-bearing lymphocytes, immunoglobulin-producing cells, and binding of IgG to glomerular components of similar molecular weight. The occurrence of both diseases in the same patient or the same families and the presence of immune abnormalities compatible with HSP or IgAN in relatives of patients with these diseases suggest a common pathogenesis. 相似文献