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ObjectiveDespite evidence that mandatory pelvic examinations deter contraceptive use and are not clinically necessary, survey research suggests that clinicians regularly perform pelvic examinations prior to prescribing contraceptives. This study estimates prevalence of nonindicated pelvic exams during contraceptive encounters, and variation in prevalence by provider specialty.Study designUsing a national sample of commercial claims data, we identified contraceptive encounters without concurrent indication for pelvic examination among females aged 15 to 49 from 2007 to 2017. We first calculated the nonindicated exam rate by provider specialty and patient age. Using data from 2017 and linear probability models with metropolitan statistical area fixed effects, we estimated the differences in adjusted rates of nonindicated pelvic examination by provider specialty. To assess trends by provider specialty, we used all years of data and interacted specialty with year.ResultsOf 7.9 million identified contraceptive encounters, 81.8% had no identified indications for pelvic exam. Exams were billed at 17.7% of these visits (2007–2017), and this rate increased from 13.4% in 2007 to 20.7% in 2017. The largest increase occurred among encounters with an obstetrician-gynecologist. In 2017, obstetrician-gynecologists were 20.3 percentage points (95% CI: 19%–21%) more likely to perform a concurrent pelvic exam compared to family physicians.ConclusionsPelvic examinations during contraceptive visits increased from 2007 to 2017. Increases occurred across all provider specialties, but were largely driven by obstetrician-gynecologists, who oversaw over half of all contraceptive encounters and performed non-indicated pelvic exams at the highest rate.ImplicationsThis research provides real-world evidence that suggests pelvic exams are increasingly performed during contraceptive encounters and that patients regularly undergo a low-value, invasive examination while obtaining contraceptive care. Continuing education, reimbursement reform, and more evidence on the harms of non-indicated pelvic exams will be necessary to change clinical practice.  相似文献   
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The hepatoprotective and antioxidant activity of 50% ethanolic extract of whole plant of Amaranthus spinosus (ASE) was evaluated against carbon tetrachloride (CCl4) induced hepatic damage in rats. The ASE at dose of 100, 200 and 400 mg/kg were administered orally once daily for fourteen days. The substantially elevated serum enzymatic levels of serum glutamate oxaloacetate transaminase (AST), serum glutamate pyruvate transaminase (ALT), serum alkaline phosphatase (SALP) and total bilirubin were restored towards normalization significantly by the ASE in a dose dependent manner. Higher dose exhibited significant hepatoprotective activity against carbon tetrachloride induced hepatotoxicity in rats. The biochemical observations were supplemented with histopathological examination of rat liver sections. Meanwhile, in vivo antioxidant activities as malondialdehyde (MDA), hydroperoxides, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) were also screened which were also found significantly positive in a dose dependent manner. The results of this study strongly indicate that whole plants of A. spinosus have potent hepatoprotective activity against carbon tetrachloride induced hepatic damage in experimental animals. This study suggests that possible mechanism of this activity may be due to the presence of flavonoids and phenolics compound in the ASE which may be responsible to hepatoprotective activity.  相似文献   
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Abstract

The current study is an effort to identify the effect of a hydroalcohol (50% ethanol) extract of roots of Cissampelos pareira. (L.) Hirsuta (Menispermaceae) (CPE) in forestomach cancer and on carcinogen metabolizing phase I and phase II enzymes along with antioxidant enzymes. In forestomach, the activities of glutathione S.-transferase (GST), DT-diaphorase (DTD), and superoxide dismutase (SOD) increased significantly and dose-dependently. The protective effect of CPE was studied against benzo(a.)pyrene [B(a.)P]-induced gastric cancer in mice, and the tumor incidence was reduced and the mean number of tumors and the tumor multiplicity were reduced significantly and dose-dependently. The modulatory effect of CPE was also examined on carcinogen metabolizing phase I and phase II enzymes, antioxidant enzymes, glutathione content, lactate dehydrogenase, and lipid peroxidation in liver. Significant increases in the levels of acid-soluble sulfhydryl (–SH) and cytochrome P450 contents and in enzyme activities of cytochrome P450 reductase, cytochrome b5 reductase, GST, DTD, SOD, catalase, glutathione (GSH) peroxidase, and GSH reductase but decreased malondialdehyde (MDA) were observed. Butylated hydroxyanisole (BHA) showed an increase in hepatic levels of GSH content, cytochrome b5, DTD, GST, glutathione reductase (GR), and catalase, whereas MDA formation was inhibited significantly. BHA also showed increased levels of DTD, GST, and SOD significantly in forestomach. The enhanced GSH level and enzyme activities involved in xenobiotic metabolism and maintaining antioxidant status of cells are suggestive of a chemopreventive efficacy of Cissampelos pareira. against chemotoxicity, including carcinogenicity.  相似文献   
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Background  Medical care at the end of life is often expensive and ineffective. Objective  To explore associations between primary care and hospital utilization at the end of life. Design  Retrospective analysis of Medicare data. We measured hospital utilization during the final 6 months of life and the number of primary care physician visits in the 12 preceding months. Multivariate cluster analysis adjusted for the effects of demographics, comorbidities, and geography in end-of-life healthcare utilization. Subjects  National random sample of 78,356 Medicare beneficiaries aged 66+ who died in 2001. Non-whites were over-sampled. All subjects with complete Medicare data for 18 months prior to death were retained, except for those in the End Stage Renal Disease program. Measurements  Hospital days, costs, in-hospital death, and presence of two types of preventable hospital admissions (Ambulatory Care Sensitive Conditions) during the final 6 months of life. Results  Sample characteristics: 38% had 0 primary care visits; 22%, 1–2; 19%, 3–5; 10%, 6–8; and 11%, 9+ visits. More primary care visits in the preceding year were associated with fewer hospital days at end of life (15.3 days for those with no primary care visits vs. 13.4 for those with ≥9 visits, P < 0.001), lower costs ($24,400 vs. $23,400, P < 0.05), less in-hospital death (44% vs. 40%, P < 0.01), and fewer preventable hospitalizations for those with congestive heart failure (adjusted odds ratio, aOR = 0.82, P < 0.001) and chronic obstructive pulmonary disease (aOR = 0.81, P = 0.02). Conclusions  Primary care visits in the preceding year are associated with less, and less costly, end-of-life hospital utilization. Increased primary care access for Medicare beneficiaries may decrease costs and improve quality at the end of life.  相似文献   
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One negative outcome associated with schizophrenia is a deterioration of cognitive functioning. Little is known about what happens to cognitive abilities in the years following a diagnosis of first-episode schizophrenia. This study assessed the cognitive functioning of 61 individuals with first-episode schizophrenia who showed significant clinical improvement (Clinical Global Improvement rating of much or very much improved) after 10 years of treatment, comparing their cognitive functioning at the time of the initial diagnosis and at 10-year follow-up. Our results indicated deterioration in some cognitive abilities at baseline with further decline in this area found after 10 years. Visuomotor integration, working memory, and executive functioning deteriorated in the 10 years of treatment following diagnosis, and many individuals who were classified as much or very much improved still demonstrated abnormal cognitive functioning. These findings suggest the need for greater focus on cognitive functioning in treatment for schizophrenia.  相似文献   
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