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101.
Different tissue macrophage subsets were immunohistochemically examined in normal endometrial samples collected from proliferative (n=4), peri-ovulatory (n=6) and secretory (n=8) phases of menstrual cycles in women. The different macrophage subsets, namely CD68 (pan macrophage marker), CD44 (transmembrane adhesion molecule), HLA-DR (transmembrane heterodimeric protein involved in antigen presentation) and L1 (calprotectin)-positive cells, as well as, CD45 (common leucocytic antigen)-positive cells were examined on the basis of immunohistochemical staining, and areas of immunoprecipitation were analyzed morphometrically using computer-assisted video imaging system. The stage-specific distribution of receptors for estrogen (ER) and progesterone (PR) in endometrial cells were examined and morphometrically analyzed. There was an increase in the number of CD45+ cells (P < 0.01) and CD68+ cells (P < 0.05) in secretory phase endometrium compared with proliferative and peri-ovulatory phases. There was no remarkable cycle dependent pattern in HLA-DR+ and L1+ cells. However, there was an increase in CD44 immunopositive area in peri-ovulatory (P < 0.05) and in secretory (P < 0.01) phases of endometrium compared with proliferative phase endometrium. A higher (P < 0.01) degree of immunopositivity for ER was observed during peri-ovulatory phase, and for PR, during peri-ovulatory (P < 0.05) and secretory (P < 0.01) phases compared with proliferative phase of cycle. Positive correlations between areas occupied by (i) CD68+ cells and PR (P < 0.01), (ii) HLA-DR+ and L1+ cells (P < 0.05), (iii) CD45+ and CD68+ cells (P < 0.01), (iv) CD45+ and L1+ cells (P < 0.05), and (v) PR and L1+ cells (P < 0.05) were obtained. It appears that the recruitment of different macrophage subsets in human endometrium involves a complex set of endocrine and paracrine factors.  相似文献   
102.
Cytoskeleton disruption is a process by which oxidative stress disrupts cellular function. This study compares and contrasts the effect of oxidative stress on the three major cytoskeleton filaments, microfilaments (MFs), microtubule (MT), and vimentin in human cortical neuronal cell line (HCN2). HCN2 cells were treated with 100 microM tertiary butylhydroperoxide (t-BuOOH), a free radical generating neurotoxin for 1, 3, or 6 h. Cell viability studies demonstrated significant cell death although the morphology studies showed that there was a substantial loss in neurites of neurons treated with t-BuOOH for 6 h. Because the cytoskeleton plays a role in neurite outgrowth, the effect of oxidative stress on the cytoskeletal was studied. In neurons subjected to oxidative stress for 30 min or 1 h, there were no major changes in microfilament distribution though there was altered distribution of microtubule and vimentin filaments as compared to controls. However, loss and disruption of all the three cytoskeletal filaments was observed at later times (3 and 6 h), which was confirmed by Western Blot analysis. Further studies were done to measure the gene expression levels of actin, tubulin, and vimentin. Results indicated that the overall loss of the cytoskeletal proteins in neurons treated with free radical generating toxin might not be a direct result of the downregulation of the cytoskeletal genes. This study shows that free radical generation in human neurons leads to the disruption of the cytoskeleton, though there may be a difference in the susceptibility to oxidative stress among the individual components of the cytoskeletal filaments.  相似文献   
103.
Aniridia (absence of iris) is a congenital, bilateral, uncommon panocular disorder. Whereas the occurrence of aniridia in the general population is 1:50000, it is present in about 1 in 70 patients with Wilm’s tumor. This aniridia is sporadic and Wilm’s tumor in these cases presents at an unusually early age. Aniridia was present in two cases out of 60 cases of Wilm’s tumor operated at PGIMS, Rohtak. Both cases presented below two years of age. The recognition of a child with sporadic aniridia should alert to the increased risk of development of Wilm’s tumor.  相似文献   
104.
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106.
Colonic mucosa in patients with portal hypertension   总被引:4,自引:0,他引:4  
BACKGROUND AND AIMS: To do a histomorphometric study of vascular changes in colonic mucosa of patients with portal hypertension (PHT) and to find their association with clinical and upper and lower gastrointestinal endoscopic observations. METHODS: Full length colonoscopy was carried out in 55 patients with portal hypertension and 25 controls. Hemorrhoids, anorectal varices and colopathy were carefully looked for and recorded. Two biopsies each were taken from the caecum, ascending colon, transverse colon, descending colon and rectum. Sections from all the five sites were examined for histopathological changes with special reference to changes in mucosal capillaries. Morphometric assessment of the diameter of the capillary and thickness of the capillary wall was performed. These histomorphometric changes were correlated with clinical parameters and findings of upper and lower gastrointestinal endoscopic findings. RESULTS: Dilated and congested capillaries as well as capillaries with irregular thickening of the wall were seen in a significantly higher number of sections from patients than controls in biopsies from all the five sites from caecum to rectum. On morphometry, the diameter of the capillaries and the thickness of the capillary wall in biopsies from all the five sites in patients was significantly higher than that in the control group. Apart from vascular changes, edema and inflammatory infiltrate in lamina propria were the other significant histological features noted. No significant association between clinical and endoscopic features and histomorphometric assessment was found. CONCLUSION: Dilated tortuous mucosal capillaries with irregular thickening of wall, edema of lamina propria and mild chronic inflammatory infiltrate are the major histopathological changes seen in colonic biopsies of patients with PHT, showing that PHT produces changes in the colonic mucosa similar to those seen in the mucosa of upper GI tract. However, the histological changes had no correlation with the clinical or endoscopic findings except that the thickness of the capillary wall was higher in patients who had undergone endoscopic sclerotherapy as opposed to those who had not received sclerotherapy.  相似文献   
107.
BACKGROUND: This is a retrospective study of left ventricle (LV) aneurysm repair done at the Escorts Heart Institute and Research Centre, New Delhi, since October 1988. Two methods of LV aneurysm repair are practiced: double breasting (DB) and Dor's repair. The method varies with location, size, and extent of aneurysm and quality of the fibrotic wall of the aneurysm. METHODS: Between October 1988 and May 2001, 129 patients underwent LV aneurysm repair using one of the two techniques; 78 patients had Dor's repair while 51 patients had DB repair. RESULTS: Overall mortality was 2.3% (three patients). One patient died in the DB group, and two patients died in the Dor's repair group. Mean preoperative ejection fraction (EF) after surgery in DB was 31% while in Dor's repair it was 29.2%. EF showed improvement after surgery to 48.5% in DB and 46.6% in Dor's repair. Decrease in end-diastolic volume (EDV) in DB was from 146 to 91.4 cm3/m2, and in Dor's repair it was from 156 cm3/m2 to 88.6 cm3/m2. Decrease in end-systolic volume was from 101 cm3/m2 to 60.2 cm3/m2 in DB and from 109 cm3/m2 to 64.5 cm3/m2 in Dor's group. All of these values showed statistically significant improvement. At six months postoperatively, 83 patients (74.1%) out of 112 patients who were preoperatively in New York Heart Association (NYHA) Functional Classes III and IV improved to class II while 7 patients (6.3%) improved to class I. CONCLUSION: In our experience Dor's repair is indicated for anteroseptal and apical isolated posterior aneurysm to restore LV volume and geometry while DB is indicated for apical, anterolateral, and lateral aneurysms where septal involvement is less. These two techniques have definite indications and advantages with good results.  相似文献   
108.
Systematic disparities in rates of HIV incidence by socioeconomic status were assessed among men attending three sexually transmitted disease (STD) clinics in Pune, India, to identify key policy-intervention points to increase health equity. Measures of socioeconomic status included level of education, family income, and occupation. From 1993 to 2000, 2,260 HIV-uninfected men who consented to participate in the study were followed on a quarterly basis. Proportional hazards regression analysis of incident HIV infection identified a statistically significant interaction between level of education and genital ulcer disease. Compared to the lowest-risk men without genital ulcer disease who completed high school, the relative risk (RR) for acquisition of HIV was 7.02 (p < 0.001) for illiterate men with genital ulcer disease, 3.62 (p < 0.001) for men with some education and genital ulcer disease, and 3.02 (p < 0.001) for men who completed high school and had genital ulcer disease. For men with no genital ulcer disease and those with no education RR was 1.09 (p = 0.84), and for men with primary/middle school it was 1.70 (p = 0.03). The study provides evidence that by enhancing access to treatment and interventions that include counselling, education, and provision of condoms for prevention of STDs, especially genital ulcer disease, among disadvantaged men, the disparity in rates of HIV incidence could be lessened considerably. Nevertheless, given the same level of knowledge on AIDS, the same level of risk behaviour, and the same level of biological co-factors, the most disadvantaged men still have higher rates of HIV incidence.  相似文献   
109.
Fetal hemoglobin (Hb F) is a major hemoglobin (Hb) component at birth. Hb F levels are markedly elevated in a number of inherited and acquired disorders. Measurement of Hb F levels is usually carried out by alkali denaturation which is not very accurate for low and high values. An accurate estimation of Hb F, and also of F cells, is desired in many hematological disorders like sickle cell disease, in monitoring the efficacy of hydroxyurea (HU) therapy, to assess feto-maternal hemorrhage (FMH) during pregnancy and in the postpartum period. We have raised a murine monoclonal antibody to human Hb F, that accurately measures the number of F cells by flow cytometry. The antibody was found to be potent and specific for F cells.  相似文献   
110.
A series of thiazole-derived N-Boc amino acids were synthesized and evaluated as targeted potential antimalarials against plasmepsins II enzyme of malaria parasite Plasmodium falciparum. All the compounds showed moderate to good activity. Compounds 3f and 3g were found to have highest the 50% inhibitory concentration (IC50) values (3.45 μM and 4.89 μM, respectively) against Plasmodium falciparum. The compounds docked to the active site of plasmepsin II. Most of the compounds were found to interact with the catalytic amino acids ASP34 and ASP214 of plasmepsin II. A good correlation was observed between binding energy and antiparasitic activity of the thiazole derivatives.  相似文献   
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