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991.
A variety of techniques have been used for quantitative estimation of renal transit time. We compared different indices of transit time in a group of 30 patients having baseline and ACE inhibitor technetium-99m mercaptoacetyltriglycine (MAG3) renography prior to arteriography: peak time, mean transit time, and the ratio of background-subtracted counts at 20 min to those at 3 min. Each index was calculated from whole-kidney ROI, cortical ROI, and cortical factor (by factor analysis). The strongest correlations between angiographic percent of stenosis and transit time index were observed for the peak time (Spearman=0.469,n=53,P <0.005) and for the R20/3 (again=0.469,n=53,P <0.005) using the whole-kidney ROI and using only the baseline data without captopril. (Spearman's is simply the correlation coefficient calculated from rank in list, which allows for nonlinear correlation.) Thus simple indices of transit time (whole-kidney peak time and R20/3) correlated as well with the observed pathology as did more complicated methods that required deconvolution, factor analysis, or selection of a cortical ROI.  相似文献   
992.
Oral administration of 20, 40, 60, mg of dry Azadirachta indica leaf powder for 24 days resulted in decrease in the weights of seminal vesicles and ventral prostate, reduction in epithelial height, nuclear diameter and the secretory material in the lumen. Biochemically, there was a decrease in total protein, acid phosphatase activities. Seminal vesicles and ventral prostate being androgen dependent, the regressive changes histologically as well as biochemically, suggests the antiandrogenic property of the neem leaves.  相似文献   
993.
994.
Growth inhibition of human breast cancer cells by herbs and phytoestrogens.   总被引:13,自引:0,他引:13  
Epidemiologic studies have suggested that consumption of phytoestrogen-rich foods may protect against breast cancer, and phytoestrogens such as genistein have been reported to both inhibit and stimulate the growth of some human breast cancer cells. The phytoestrogens genistein, daidzein, biochanin A, and coumestrol were tested and found to inhibit serum-stimulated growth in both T-47D and MCF-7 breast cancer cells at 10-100 microM. Extracts of several estrogenic herbs, including hops, black cohosh and vitex, inhibited growth of T-47D cells. These in vitro results suggest that certain herbs and phytoestrogens may have potential in the prevention of breast cancer.  相似文献   
995.
Summary The effect of conditioned medium from human breast fibroblasts on growth and 17-estradiol dehydrogenase (E2DH) activity of the MCF-7 human breast cancer cell line has been investigated. Fibroblasts were derived from normal and tumorous (benign and malignant) breast tissue. Conditioned medium from normal derived fibroblasts inhibited the growth of MCF-7 cells, the effect being statistically significant by day 3 of culture. In contrast, conditioned medium from benign and malignant derived fibroblasts significantly enhanced the growth of MCF-7 cells by day 9 of culture. When added to MCF-7 cells for three days, conditioned medium from all three types of fibroblasts increased E2DH activity in the reductive direction (estrone (E1) estradiol (E2)) 2–3 fold. There was little or no effect on the oxidative direction (E2 E1). After 12 days, enzyme activity in the reductive direction was still markedly increased, the effect being greatest in conditioned medium from fibroblasts derived from malignant breast tissue, and least in conditioned medium from fibroblasts derived from benign breast tumors. These results demonstrate that human breast fibroblasts may have paracrine influences on neighbouring epithelial cellsin vivo.  相似文献   
996.

Introduction

Interventional radiology (IR) plays a vital role in modern medicine, with increasing demand for services, but with a shortage of experienced interventionalists. The aim of this study was to determine the impact of a recently introduced IR curriculum on perception, knowledge, and interest of medical students regarding various aspects of IR.

Methods

In 2014, an anonymous web-based questionnaire was sent to 309 4th year medical students in a single institution within an EU country, both before and after delivery of a 10-h IR teaching curriculum.

Results

Seventy-six percent (236/309) of the respondents participated in the pre-IR module survey, while 50 % (157/309) responded to the post-IR module survey. While 62 % (147/236) of the respondents reported poor or no knowledge of IR compared to other medical disciplines in the pre-IR module survey, this decreased to 17 % (27/157) in the post-IR module survey. The correct responses regarding knowledge of selected IR procedures improved from 70 to 94 % for venous access, 78 to 99 % for uterine fibroid embolization, 75 to 97 % for GI bleeding embolization, 60 to 92 % for trauma embolization, 71 to 92 % for tumor ablation, and 81 to 94 % for angioplasty and stenting in peripheral arterial disease. With regard to knowledge of IR clinical roles, responses improved from 42 to 59 % for outpatient clinic review of patients and having inpatient beds, 63–76 % for direct patient consultation, and 43–60 % for having regular ward rounds. The number of students who would consider a career in IR increased from 60 to 73 %.

Conclusion

Delivering an undergraduate IR curriculum increased the knowledge and understanding of various aspects of IR and also the general enthusiasm for pursuing this specialty as a future career choice.
  相似文献   
997.
998.

Purpose

To compare information from self-report and electronic medical records for four common comorbidities (diabetes, hypertension, myocardial infarction, and other heart diseases).

Methods

We pooled data from two multiethnic studies (one case–control and one survivor cohort) enrolling 1,936 women diagnosed with breast cancer, who were members of Kaiser Permanente Northern California.

Results

Concordance varied by comorbidity; kappa values ranged from 0.50 for other heart diseases to 0.87 for diabetes. Sensitivities for comorbidities from self-report versus medical record were similar for racial/ethnic minorities and non-Hispanic Whites, and did not vary by age, neighborhood socioeconomic status, or education. Women with a longer history of comorbidity or who took medications for the comorbidity were more likely to report the condition. Hazard ratios for all-cause mortality were not consistently affected by source of comorbidity information; the hazard ratio was lower for diabetes, but higher for the other comorbidities when medical record versus self-report was used. Model fit was better when the medical record versus self-reported data were used.

Conclusions

Comorbidities are increasingly recognized to influence the survival of patients with breast or other cancers. Potential effects of misclassification of comorbidity status should be considered in the interpretation of research results.
  相似文献   
999.
Skeletal dysplasias (SDs) are highly heterogeneous disorders composed of 40 clinical sub‐types that are part of 456 well‐delineated syndromes in humans. Here, we enrolled consanguineous kindred from a remote area of Sindh province of Pakistan, with 14 affected individuals suffering with short stature, kyphoscoliosis, joint dislocations, clubfoot, heart valve anomalies and progressive bilateral mixed hearing loss. To identify pathogenic variants in this family, whole exome sequencing (WES) was performed in one affected and one normal individual, which revealed a novel transversion mutation (c.802G>T; p.Glu268*) in CHST3 associated with the phenotype. CHST3 encodes a chondroitin 6‐O‐sulfotransferase‐1 (C6ST‐1) enzyme that is essential for the sulfation of proteoglycans found in cartilages. Previously, mutations in CHST3 have largely been reported in sporadic cases of SD, primarily with severe spinal abnormalities, joint dislocations, joint contractures, and clubfoot. Clinical and radiological examination of the affected individuals in this family provides new insights into phenotypic spectrum of CHST3 alleles and disease progression with age.  相似文献   
1000.
Radiofrequency ablation (RFA) has established itself as a first-line therapy for the curative treatment of many patients with supraventricular or atrioventricular tachycardias and has exhibited a generally low incidence of serious sequelae (N Engl J Med. 1991;324:1612; Lancet. 1991;337:1557). Coronary artery injury is a rare complication. We present a patient with an acute thrombotic total occlusion of the left main coronary artery immediately after the end of RFA who was successfully treated with emergency percutaneous transluminal coronary angioplasty. This case illustrates an unusual coronary complication of RFA and serves as an exceptional example of survival with a good short-term prognosis after this unusual etiology of myocardial infarction.  相似文献   
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