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11.
The neuronal form of nitric oxide synthase (NOS-1) has been localized to several cell types in the retinas of experimental animals; however, localization in the human retina has not been definitive. By using in situ hybridization and immunohistochemistry, we have compared the cellular expression and localization of NOS-1 in the rat and human retinas. In both rat and human retinas, NOS-1 is expressed in the inner segments of photoreceptors, cells in the inner nuclear layer, particularly amacrine cells, and retinal ganglion cells. In human cones, NOS-1 is abundantly present in the outer segments. In the rat, optic nerve transection caused a loss of cells that were positive for NOS-1 in the ganglion cell layer. Although a retinal ganglion cell localization has not been reported consistently in the literature, our data clearly localize NOS-1 to the retinal ganglion cells of the rat and human retinas.  相似文献   
12.
JUSTIFICATION: Acute rheumatic fever and rheumatic chronic valvular heart disease is an important preventable cause of morbidity and mortality in suburban and rural India. Its diagnosis is based on clinical criteria. These criteria need verification and revision in the Indian context. Furthermore, there are glaring differences in management protocols available in literature. These facts prompted Indian Academy of Pediatrics to review the management of rheumatic fever. PROCESS: Management of Rheumatic fever was reviewed and recommendation was formulated at national consultative meeting on 20th May 2007 at New Delhi. OBJECTIVES: To formulate uniform guidelines on management of acute rheumatic fever and rheumatic heart disease in the Indian context. Guidelines were formulated for the management of streptococcal pharyngitis, acute rheumatic fever and its cardiac complication as well as secondary prophylaxis for recurrent episodes. RECOMMENDATIONS: (1) Streptococcal eradication with appropriate antibiotics (Benzathine penicillin single dose or penicillin V oral or azithromycin). (2) Diagnosis of rheumatic fever based on Jones criteria. (3) Control inflammatory process with aspirin with or without steroids (total duration of treatment of 12 weeks). (4) Treatment of chorea according to severity (therapy to continue for 2-3 weeks after clinical improvement). (5) Protocol for managing cardiac complication like valvular heart disease, congestive heart failure and atrial fibrillation. (6) Secondary prophylaxis with benzathine penicillin and management of anaphylaxis.  相似文献   
13.
Extracellular matrix of the human lamina cribrosa   总被引:6,自引:0,他引:6  
We used immunoperoxidase staining and double immunofluorescent staining to demonstrate the macromolecular components of the extracellular matrix of the lamina cribrosa from young human donors. The cribriform plates were made up of a core of elastin fibers with a sparse, patchy distribution of collagen type III. The plates were coated with collagen type IV and laminin; these basement membrane components were presumably made by the astrocytes that were distributed on the surfaces of the plates. The insertion of the lamina cribrosa in the sclera was made up of concentric, circumferential elastin fibers that surrounded the lamina cribrosa and were continuous with the elastin in the cribriform plates. Astrocytic processes extended into the bundles of elastin fibers, whereas the basement membrane components extended into the sclera. The mechanical properties of the macromolecules of the extracellular matrix of the lamina cribrosa may make this tissue compliant and sensitive to intraocular pressure. Perhaps individual differences in the macromolecular components of this tissue contribute to the glaucomatous changes in the optic nerve head.  相似文献   
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Supplementation in malnourished pregnant women should not displace natural healthy foods. Objective: To estimate the differential effects of three nutritional supplements on macro- and micronutrient intake of pregnant women beneficiaries of the conditional cash transfer program Prospera (CCT-POP). Methods: Prospective cluster randomized trial. Communities were randomly assigned to receive a fortified beverage (Beverage), micronutrient tablets (Tablets), or micronutrient powder (MNP). Pregnant women (at <25 weeks) were recruited. The food frequency questionnaire was applied at 25 and 37 weeks of pregnancy and at one and three months postpartum (mpp). Differential effects of the three supplements on the median change in nutrient intake from baseline to each follow-up stage were estimated. Results: Median change in protein intake from dietary and supplement sources were significantly lower for MNP and Tablets than for Beverages (baseline to 37 w: −7.80 ± 2.90 and −11.54 ± 3.00, respectively; baseline to 1 mpp: −7.34 ± 2.90 for MNP, p < 0.001). Compared to Beverages, median increases were higher for the MNP for vitamins C (31.2 ± 11.7, p < 0.01), E (1.67 ± 0.81, p < 0.05), and B12 (0.83 ± 0.27, p < 0.01) from baseline to 37 wk; from baseline to 1 mpp, there was a higher median increase in B12 (0.55 ± 0.25, p < 0.05) and folate (63.4 ± 24.3, p < 0.01); and from baseline to 3 mpp, a higher median increase in iron (2.38 ± 1.06, p < 0.05) and folate (94.4 ± 38.1, p < 0.05). Conclusions: Intake of micronutrients was higher for MNP and Tablets, likely due to food displacement among Beverage consumers. Although iron bioavailability and absorption inhibitors were not considered for the present analyses, the distribution of Tablets or MNP had several advantages in this context where micronutrient deficiency remains high among pregnant women, but macronutrient intake is generally adequate or even high.  相似文献   
17.
Aquatic birds are commonly affected by oil spills. Despite rehabilitation efforts, the majority of rehabilitated common guillemots (Uria aalge) do not survive, whereas mute swans (Cygnus olor) tend to have higher postrelease survival. Polyaromatic hydrocarbons (PAHs) present in crude oil and diesel are immunotoxic in birds affecting cell-mediated responses to immunogens. Because it is a target of PAH toxicity, T-lymphocyte response to controlled mitogen administration (phytohemagglutinnin test) was investigated in a scoping study as a potentially useful minimally invasive in vivo test of cell-mediated immunity. The test was performed on 69 mute swans and 31 common guillemots stranded on the Norfolk and Lincolnshire coastline and inland waterways in England (UK) either due to injury or to contamination with crude or diesel oil. T-lymphocyte response was significantly decreased in swans with greater oil scores. T-lymphocyte responses were also decreased in guillemots, but this finding was not statistically significant.  相似文献   
18.
Myeloproliferative neoplasms (MPNs) are malignant disorders originating from clonal expansion of a single neoplastic stem cell and characteristically show an increase in bone marrow reticulin fibers. Lysyl oxidases (LOXs) are copper‐dependent amine oxidases that play a critical role in the biogenesis of connective tissue by crosslinking extracellular matrix proteins, collagen and elastin. Expression of LOX gene family members is increased in disorders associated with increased fibrosis. To evaluate involvement of LOX gene family in various MPNs. In‐situ hybridization was used to detect Lysyl‐Oxidase family members in bone marrow biopsies from patients with different MPNs. We compared normal bone marrows and those from patients with polycythemia vera, essential thrombocythemia, chronic myeloid leukemia, and primary myelofibrosis (PMF). Serum levels of lysyl‐oxidase from patients with PMF and healthy controls were also examined. LOX gene family was not detected in normal bone marrows. All members of the LOX gene family were over expressed in PMF. In other MPNs a differential pattern of expression was observed. Differences in gene expression were statistically significant (P < 0.010). The medianserum LOX levels in normal controls was 28.4 ± 2.5 ngml and 44.6 ± 9.44 ngml in PMF (P = 0.02). The varying pattern of expression of LOX genes may reflect differences in the pathophysiology of bone marrow fibrosis in these MPNs. These observations could be used as the basis for future targeted therapy directed against bone marrow fibrosis. Am. J. Hematol. 88:355–358, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
19.

Objectives

Self-rated health (SRH) is a powerful concept that has greatly advanced our understanding of health and health outcomes. The SRH measure has become increasingly common in health research. Yet, puzzles remain about what shapes SRH ratings. The absence of knowledge is particularly acute in the context of disability. The aim of this study was to examine the relationship between SRH and self-rated physical ability in a sample of individuals with spinal cord injury (SCI).

Methods

Data from 140 eligible participants drawn from a study of life in the community after SCI were analyzed. The study, cross-sectional in design, was conducted in a large urban city in the mid-western United States. Basic statistics such as ANOVA and chi-square tests were performed as appropriate, and a multiple linear regression analysis modeled the relationship between SRH and physical ability adjusting for potential confounding variables.

Results

Self-rated physical ability was significantly associated with SRH after controlling for relevant covariates (P < 0.001). An analysis of the interaction between physical ability and level of injury revealed that the relationship was significant for persons with paraplegia but not for persons with tetraplegia.

Conclusions

This study provides evidence that self-rated physical ability is an important factor associated with SRH for persons with SCI, but that the strength of the relationship depends on level of injury (paraplegia vs. tetraplegia). The challenge for future research is to replicate the study using a more comprehensive measure of physical ability and to ask how beliefs in one''s ability to do those activities that are most meaningful and desired shape SRH. Only in this way will our understanding of the physical ability–SRH relationship be clarified.  相似文献   
20.
Intrathoracic pressure variations are currently proposed as the main flow-generation mechanisms in standard and modified cardiopulmonary resuscitation (CPR) techniques. A method of changing pressure within the thorax and abdomen without any degree of heart compression was developed and tested in dogs. Intrathoracic and abdominal pressure waves were induced by cyclic inflation and deflation of the lungs and of perithoracic and periabdominal balloons. Various modes of CPR, depending on the rate of cycling, the use of a periabdominal balloon inflation, and a delay between the abdominal and thoracic pressure waves, were studied during ventricular fibrillation. During artificial systole (high intrathoracic pressure phase), the pressure which developed in the right ventricle (96.7 +/- 20.5 mmHg) was higher than the pressure in the aorta (89.3 +/- 20.5 mmHg, p less than 0.001). In artificial diastole (low intrathoracic pressure phase), the right ventricular pressure (11.7 +/- 2.6 mmHg) was lower than the aortic pressure (17.5 +/- 3.3 mmHg, p less than 0.001). The average flow in the carotid artery was 21.7 +/- 7.8 ml . min-1, which was 18 +/- 6% of the baseline carotid flow before CPR. Three different factors were found to improve the efficiency of CPR: periabdominal balloon inflation simultaneous with the intrathoracic pressure waves; increased frequency of the pressure waves from 60 to 100 cycles per minute; and inflation of the periabdominal balloon 50 to 100 ms before the thoracic balloon. Blood-gas and acid-base balance analysis during CPR revealed well-oxygenated arterial blood with a marked respiratory alkalosis and a slowly developing metabolic acidosis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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