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31.
We studied a random sample of Japanese and compared both Japanese and German monocyte antigen frequencies and performed a segregation analysis in Japanese families. In Japanese, the following gene frequencies were established: 0.1033 for HMA-A1; 0.0299 for HMA-A3; 0.0033 for HMA-A6; 0.1521 for HMA-B2. Data on the gene frequency in Germans were presented by Rose. In this comparison, the frequency for HMA-B2 in Japanese is more than two times higher; for antigen HMA-A6, the Japanese is a fifth of the German quantity. The antigen HMA-B4 was not found in Japanese. The results we obtained from family analysis confirmed an unambiguous autosomal, codominant inheritance of the examined HMA antigens.  相似文献   
32.
Metabolic labeling and quantitative 2D gel autoradiography were used to assess changes in the synthesis and transport of GAP-43 in entorhinal cortex (EC) neurons and perforant pathway during lesion-induced sprouting and reactive synaptogenesis. In normal adult rats, there is a high constitutive level of GAP-43 synthesis and transport in EC neurons projecting to the hippocampus. Following unilateral EC lesions, there is a 2-fold (100%) increase in the transport of newly synthesized GAP-43 to the contralateral or 'sprouting' hippocampus. The timing of this upregulation (between 6 and 15 days) suggests that changes in GAP-43 expression occur in response to the growth of presynaptic terminals during sprouting.  相似文献   
33.
The present study investigated whether single-dose oral leukotriene receptor antagonists as add-on therapy to short-acting beta-agonists, immediately after allergen challenge, block the late-phase airway response. In total, 35 mild asthmatics (mean age 24 yrs, 19 males) sensitised for house dust mites underwent two courses of bronchial allergen challenge. After the early allergic response (EAR), subjects received salbutamol once and were randomly assigned to either 10 mg of montelukast or placebo (double-blind crossover). To identify a late allergic response, forced expiratory volume in one second (FEV(1)) was monitored over the following 8 h. Baseline exhaled nitric oxide (NO) was determined ahead of each allergen challenge. Baseline NO levels differed significantly depending on the reaction to allergen challenge. In total, 12 subjects showed no significant response, 11 only showed an EAR, and 12 had a dual response and underwent further analysis. The area under the FEV(1) time-response curve 3-8 h after bronchial allergen challenge was -0.77+/-1.68 from the pre-challenge values on montelukast compared with -2.47+/-1.32 on placebo. The baseline exhaled NO fraction of subjects without an EAR was significantly lower than of those presenting a dual response. The results of the present study demonstrate that single-dose leukotriene receptor antagonists given orally right after the early allergic response can significantly inhibit the late allergic response after bronchial allergen challenge.  相似文献   
34.
Although breast milk is recommended as the optimal source of infant nutrition, breastfeeding initiation is below recommended levels, especially among teenage mothers. Breastfeeding initiation rates among Michigan (US) teenage mothers (12-19 y) were compared by demographics and health behaviors. Multivariate analyses determined which factors were significant independent predictors of breastfeeding initiation among teenage mothers enrolled prenatally in the Michigan Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) program in 1995. Significant predictors independently associated with breastfeeding initiation were race/ethnicity, education, marital status, postpartum anemia status, parity, prenatal trimester of WIC enrollment, and smoking. The strongest predictor of breastfeeding initiation differed for white mothers (positive predictor: education beyond high school [OR = 3.13]) and black mothers (negative predictor: multiparous [OR = 0.25]). Initiation rates for this population of teenage mothers fall below the national average for mothers of all ages and the US Healthy People 2010 goals. Research is needed concerning how breastfeeding support and education can be improved to reach the US national health goals.  相似文献   
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36.
The surgical techniques and results after extraperiorbital implantation of Silastic on the orbital floor of 70 patients are reviewed. In 11 patients the implant was through a subciliary approach and in 59 through an inferolateral cantholysis. The inferolateral cantholysis, a simplification of the McCord and Moses approach to the orbital floor, is particularly suited to this application. The implanted Silastic was retained in 66 patients, with an average follow up of 3.5 years (range less than 1 to 9.5 years), though six required surgery to debulk the anterior end of the implant. Further surgery was required in 27 patients, this generally being to correct the position of either the upper or the lower lid. Volume enhancement was effective in most cases, there being a significant reduction in the degree of recession of the prosthesis and the depth of the unsightly sunken sulci of the upper and lower lids. The mobility of the orbital contents, the prosthesis, and the upper lid was not improved.  相似文献   
37.
Isoniazid chemoprophylaxis is not recommended for all persons infected with tubercle bacilli. Because of the small but significant risk of isoniazid hepatotoxicity, chemoprophylaxis is reserved for only those at the highest risk of tuberculosis activation. To evaluate this policy, we performed a cost-effectiveness analysis of isoniazid chemoprophylaxis for two populations with positive tuberculin skin tests: recent tuberculin converters, who are at high risk for activation, and older tuberculin reactors, who have a low risk for activation and for whom chemoprophylaxis is not now recommended. The cost-effectiveness ratios found were stable, despite wide variations in model assumptions and probability estimates. For high-risk tuberculin reactors, chemoprophylaxis resulted in net medical care monetary savings, extended life expectancy, and fewer fatal illnesses. For low-risk tuberculin reactors, chemoprophylaxis resulted in positive, but small, health effects. Because the cost to gain these positive effects were also small, the resulting cost-effectiveness ratios were reasonable and in the realm of accepted prevention strategies: $12,625 to gain one year of life and $35,011 to avert one death. These findings suggest that the current policy is too restrictive and that many in the large population of low-risk tuberculin reactors should be considered for isoniazid chemoprophylaxis.  相似文献   
38.
Human prostate cancer (PC) cell lines possess epidermal growth factor (EGF) receptors and secrete EGF-related polypeptides. We used an EGF receptor-blocking antibody (anti-EGF.R) to demonstrate a functional autocrine loop, as well as the interaction between this and the effects of linoleic acid (LA), an omega-6 fatty acid, on PC cell growth. The anti-EGF.R competed effectively with [125I]EGF for receptors on DU145 PC cells, and on a high-passage DU145 variant (DU145M); when added to the culture medium, it suppressed both DU145 and DU145M cell growth in a dose-dependent manner. LA, a precursor for eicosanoid synthesis, had little effect on DU145 cell growth rate but stimulated DU145M growth in a concentration-related manner over a range of 0.25-2.0 micrograms/ml. anti-EGF.R (10(-9) M) caused suppression of LA-stimulated growth of DU145M cells in serum-free medium, which was prevented by the addition of 2 nM EGF. We conclude that an EGF.R-mediated autocrine loop is involved in PC cell growth regulation and that at least one site of action may be the synthesis of eicosanoids from their LA precursor.  相似文献   
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40.
PURPOSE: Some researchers (F. R. Vellutino, F. M. Scanlon, & M. S. Tanzman, 1994) have argued that the different domains comprising language (e.g., phonology, semantics, and grammar) may influence reading development in a differential manner and at different developmental periods. The purpose of this study was to examine proposed causal relationships among different linguistic subsystems and different measures of reading achievement in a group of children with reading disabilities. METHODS: Participants were 279 students in 2nd to 3rd grade who met research criteria for reading disability. Of those students, 108 were girls and 171 were boys. In terms of heritage, 135 were African and 144 were Caucasian. Measures assessing pre-reading skills, word identification, reading comprehension, and general oral language skills were administered. RESULTS: Structural equation modeling analyses indicated receptive and expressive vocabulary knowledge was independently related to pre-reading skills. Additionally, expressive vocabulary knowledge and listening comprehension skills were found to be independently related to word identification abilities. CONCLUSION: Results are consistent with previous research indicating that oral language skills are related to reading achievement (e.g., A. Olofsson & J. Niedersoe, 1999; H. S. Scarborough, 1990). Results from this study suggest that receptive and expressive vocabulary knowledge influence pre-reading skills in differential ways. Further, results suggest that expressive vocabulary knowledge and listening comprehension skills facilitate word identification skills.  相似文献   
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