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21.
Of 1,500 cervical tissue specimens, 27 cases showed histologic changes of reactive glandular atypia which we defined as endocervical cells with large hyperchromatic, often irregular nuclei, which did not fulfill the criteria for endocervical adenocarcinoma. Eighteen of these 27 cases had preceding or concurrent cervico-vaginal smears. Six of these showed cells which were similar to those seen in histologic sections. The cytologic characteristics of these cells are defined. To determine if atypia is related to inflammatory-regenerative changes, 29 cases of endocervical polyps were examined, of which 11 showed histologic changes of endocervical reactive atypia; 4 showed these changes cytologically as well. Twenty-eight cases of routine hysterectomy specimens were examined, of which 2 cases showed endocervical reactive atypia, which indicated that the atypical changes were indeed reactive. Nine out of 27 cases were associated with hormonal usage. Fourteen cases were associated with squamous intraepithelial lesions or evidence of human papilloma virus. Follow-up of our 27 index cases revealed no progression to adenocarcinoma. These findings indicate that atypia, as we define it, of the endocervix can be due to inflammatory-reparative changes or possibly related to hormonal usage, and permit its separation from precursor lesions of endocervical adenocarcinoma.  相似文献   
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We report three new cases of chromosome 13 derived marker chromosomes, found in unrelated patients with dysmorphisms and/or developmental delay. Molecular cytogenetic analysis was performed using fluorescence in situ hybridization (FISH) with chromosome-specific painting probes, alpha satellite probes, and physically mapped probes from chromosome 13q, as well as comparative genomic hybridization (CGH). This analysis demonstrated that these markers consisted of inversion duplications of distal portions of chromosome 13q that have separated from the endogenous chromosome 13 centromere and contain no detectable alpha satellite DNA. The presence of a functional neocentromere on these marker chromosomes was confirmed by immunofluorescence with antibodies to centromere protein-C (CENP-C). The cytogenetic location of a neocentromere in band 13q32 was confirmed by simultaneous FISH with physically mapped YACs from 13q32 and immunofluorescence with anti-CENP-C. The addition of these three new cases brings the total number of described inv dup 13q neocentic chromosomes to 11, representing 21% (11/52) of the current overall total of 52 described cases of human neocentric chromosomes. This higher than expected frequency suggests that chromosome 13q may have an increased propensity for neocentromere formation. The clinical spectrum of all 11 cases is presented, representing a unique collection of polysomy for different portions of chromosome 13q without aneuploidies for additional chromosomal regions. The complexity and variability of the phenotypes seen in these patients does not support a simple reductionist view of phenotype/genotype correlation with polysomy for certain chromosomal regions.  相似文献   
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Bacillus thuringiensis strains produce crystal delta-endotoxins which exhibit a diverse toxicity spectrum. In order to explore the basis of toxin specificity, a comparison of the activity of 13 strains belonging to seven serotypes was made against three insect species. The delta-endotoxin crystals were purified and their polypeptide composition analyzed by SDS-PAGE. Among the strains studied, the delta-endotoxins consist of a variety of crystal proteins in the 60-144 KDa size range. On the basis of molecular mass, endotoxins maybe grouped into two classes; one contained both high (125-144 KDa, P1) and medium sized (60-66 KDa, P2) proteins and a second class consisting of only the high Mr polypeptides. Immunoblotting with B. aizawai P1 antiserum revealed antigenic cross-reaction with one or more of the polypeptides in 125-144 KDa range in all the strains studied. When the crystal proteins from different strains were immunoblotted with kurstaki P2 antiserum, none of the P1 protein crossreacted suggesting that the P1 and P2 proteins are not structurally related. However, the B. kurstaki P2 antiserum crossreacted with 66 KDa proteins in some other strains which underlines a structural homology in this class of the toxic polypeptides. Toxicity studies revealed that the high Mr P1 proteins of all the strains in this study were active against lepidopteran (Pieris brassicae and Diacrisia obliqua) larvae. B. thuringiensis aizawai strains exhibit a dual toxicity associated with the high Mr (130-135 KDa; P1) proteins. The P2 crystal proteins (60-66 KDa) also showed dual toxicity against the lepidopteran and dipteran larvae but were found to be structurally and immunologically distinct.  相似文献   
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Journal of Public Health - Depression is a major morbidity and the most common mental disorder among the medical students in medical schools globally. Undergraduate students suffer stress more due...  相似文献   
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The COVID-19 outbreak started as pneumonia in December 2019 in Wuhan, China. The subsequent pandemic was declared as the sixth public health emergency of international concern on January 30, 2020, by the World Health Organization. Pakistan could be a potential hotspot for COVID-19 owing to its high population of 204.65 million and its struggling health care and economic systems. Pakistan was able to tackle the challenge with relatively mild repercussions. The present analysis has been conducted to highlight the situation of the disease in Pakistan in 2020 and the measures taken by various stakeholders coupled with support from the community to abate the risk of catastrophic spread of the virus.  相似文献   
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Introduction

Studies have shown mixed findings regarding the impact of immigration policy changes on immigrants’ utilization of primary care.

Methods

We used a difference-in-differences analysis to compare changes in missed primary care appointments over time across two groups: patients who received care in Spanish, Portuguese, or Haitian Creole, and non-Hispanic, white patients who received care in English.

Results

After adjustment for age, sex, race, insurance, hospital system, and presence of chronic conditions, immigration policy changes were associated with an absolute increase in the missed appointment prevalence of 0.74 percentage points (95% confidence interval: 0.34, 1.15) among Spanish, Portuguese and Haitian-Creole speakers. We estimated that missed appointments due to immigration policy changes resulted in lost revenue of over $185,000.

Conclusions

We conclude that immigration policy changes were associated with a significant increase in missed appointments among patients who receive medical care in languages other than English.

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The objective of this study is to compare the empirical allometric approaches with species invariant time methods using equivalent time, kallynochron, apolysichron, and dienetichrons. Pharmacokinetic parameters (clearance, volume of distribution, and elimination half-life) of ethosuximide, cyclosporine and ciprofloxacin were scaled-up from animal data obtained from the literature. Two methods were utilized to generate plots for the prediction of clearance in humans: (i) clearance versus body weight (simple allometric equation); and (ii) the product of clearance and maximum life-span potential (MLP) versus body weight. Plasma concentrations of each of the drugs were predicted using elementary and complex Dedrick plots, equivalent time with an exponent of 0.25 and equivalent time with the exponent obtained from the plot of body weight and half-life. Plasma concentrations of cyclosporine and ciprofloxacin were also predicted by MLP normalization (dienetichrons). Almost similar results in the pharmacokinetic parameters of the tested drugs were obtained by the allometric approach and by the species invariant time methods.  相似文献   
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