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71.
BackgroundNational Institute for Health and Clinical Excellence guidelines (CG87) recommend neutral protamine hagedorn (NPH) insulin for the provision of basal insulin in type 2 diabetes, but use of analogue insulin is as much as 40%. Where residual endogenous insulin secretory capacity is present there is no evidence that analogue insulins provide any additional benefit over human insulins, and they come at an expensive premium. Anecdotally, however, there is a reluctance to switch people back to NPH insulin, partly because of a perceived risk of pancreatic failure and potential ketosis. Urinary C-peptide creatinine ratio (UCPCR) has been validated as a method for evaluating residual endogenous insulin secretion in type 1 and type 2 diabetes, with a UCPCR of no more than 0·2 nmol/mmol suggestive of absolute insulin deficiency. We aimed to evaluate the prevalence of true insulin deficiency among patients with type 2 diabetes with UCPCR, and confirm findings with the gold standard mixed meal tolerance test (MMTT).Methods191 insulin-treated patients with a clinical diagnosis of type 2 diabetes (diagnosed at or after age 45 years and who did not start insulin within the first year of diagnosis) collected a 2-h post-prandial urine sample for UCPCR measurement. Nine patients from two subgroups (UCPCR ≤0·2 nmol/mmol and UCPCR >0·2) completed a standard MMTT.Findings11 (5·8%) of 191 patients had two consistent UCPCRs of less than or equal to 0·2 nmol/mmol. Nine were able to do the MMTT, of whom five were confirmed to have absolute insulin deficiency (stimulated serum c-peptide <0·2 nmol/L). Three of these five patients were glutamic acid decarboxylase antibody-negative. Nine of nine patients with UCPCR of more than 0·2 nmol/L had confirmed endogenous insulin secretion in their MMTT. Those with insulin deficiency had a shorter time to starting insulin (median 2·5 years [IQR 1·5–3·0] vs 6·0 [3·0–10·75], p=0·005) and lower body-mass index (25 kg/m2 vs 29, p=0·04) but no other significant differences in clinical characteristics.InterpretationWe have demonstrated a very low prevalence of true pancreatic failure in this population of insulin-treated patients with type 2 diabetes. This requires further exploration by comparison of a population being treated with NPH insulin with one on analogue insulin, and then determining whether UCPCR could act as a clinical decision support tool to safely switch from analogue insulin to NPH insulin.FundingNational Institute for Health Research.  相似文献   
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Reflux esophagitis (RE) and Barrett’s esophagus (BE) belong to the most common esophageal complications of gastroesophageal reflux disease. Glutathione S-transferase (GST) enzymes play an important role in cellular protection against oxidative stress and toxic foreign chemicals. Therefore, we investigated the hypothesis that polymorphisms in genes for these detoxifying enzymes could influence susceptibility to RE and BE. GSTM1, GSTT1 and GSTP1 loci were analyzed by PCR-based methods in 64 patients with RE (and an additional group of 22 subjects with BE as the fourth grade of esophagitis) and 173 unrelated controls. There were no significant differences in the distributions of GSTM1 and GSTT1 genotypes between the controls and patients with RE or BE. Similarly, frequencies of GSTP1 alleles were non-significantly different between the control and RE groups. However, GSTP1 B allele carriers were more frequent among the patients with BE compared to those in the reflux esophagitis group (P = 0.04, OR = 2.10, 95% CI 0.99–4.44) and most significantly when compared to the controls (P = 0.0067, P corr < 0.05, OR = 2.56, 95%CI 1.30–5.05). Although the GSTM1 and GSTT1 genes did not show any relationship with reflux disease, the GSTP1 gene might be one of the risk factors associated with susceptibility to RE, especially to BE.  相似文献   
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Arrhythmias and even sudden death may be caused by acute infectious myocarditis. We therefore recorded 24-hour electrocardiograms in 26 myocarditis patients both one week and two to three months after the detection of myocarditis. Two of the patients were also monitored on the first day of their symptomatic myopericarditis . Twenty-eight control subjects had recordings one to two weeks after the onset of acute uncomplicated infections. One of the two patients monitored during the first day of myopericarditis had repetitive, asymptomatic bursts of ventricular tachycardia. In the 1-week recordings 27% of the myocarditis patients and 7% of the control subjects (p less than 0.06) had complex ventricular premature beats; these occurred in only 8% of the myocarditis patients during the late recording. However, the overall number of ventricular premature beats was low in both groups and recordings. A lengthening of the QT interval was related (p less than 0.05) to the occurrence of complex premature beats in repeated recordings in the same individuals. The heart rate was higher (p less than 0.02) in myocarditis patients, but no significant difference was noted in the frequency of conduction defects. We conclude that there seems to be no reason for a prolonged restriction of physical activity during clinically uncomplicated recovery from mild acute myocarditis. However, potentially dangerous arrhythmias may occur during the very first days of the disease.  相似文献   
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Several studies have reported that older black and Latino adults have lower cognitive function test scores than older white adults, but few have comprehensively examined reasons for score differences. This study evaluates whether differences in health and socioeconomic indicators, including literacy level, can explain differences in cognitive function test scores between older black and white adults.  相似文献   
77.
Right ventricle myocardial infarctions (RVMIs) accompany inferior wall ischemia in up to one-half of cases. The clinical sequelae of RVMIs vary from no hemodynamic compromise to severe hypotension and cardiogenic shock. Diagnosis is based on physical examination, electrocardiography, echocardiography and coronary angiography. Because the standard 12-lead electrocardiogram is insufficient for the assessment of RV involvement, right-sided precordial leads should always be included. Adequate fluid administration in combination with positive inotropic agents and early coronary reperfusion are crucial components of treatment, while diuretics and nitrates should be avoided. Intra-aortic balloon counterpulsation and right ventricle assist devices may be used with success in RVMIs associated with medically refractory heart failure. Right ventricular involvement appears to be an independent prognostic factor that dramatically increases in-hospital mortality, due, in part, to a significantly higher risk of hemodynamically compromising arrhythmias. Thus, using right-sided precordial leads and early RVMI identification to trigger an appropriately aggressive treatment protocol may improve patients’ prognosis.  相似文献   
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Interval colorectal cancers (I-CRCs) arise during the interval time period between scheduled colonoscopies. Predicting which patients are at risk of I-CRCs remains an elusive undertaking, but evidence would suggest that most I-CRCs arise from lesions missed on index endoscopy. The procedural factors that lead to missed lesions are numerous and lack consensus in the literature. In Canada, the province of Newfoundland and Labrador has the highest incidence of CRCs. In this study our aim was to examine I-CRCs (3–60 months after last colonoscopy) in NL through a population-level analysis covering 67% of the province from 2001–2018. We estimated the I-CRC rate to be up to 9.3%. Median age of I-CRC diagnosis was 67.1 years with an interval time of 2.9 years. About 57% of these tumors occurred proximal to the splenic flexure, with 53% presenting as local disease. No temporal differences were observed in interval time or tumor distribution. On univariate and multivariable logistical regression, risk of right-sided I-CRC did not correlate to the index colonoscopy indication, bowel preparation quality, size of largest polyp removed, colonoscopy completion rate, or stage at presentation. Improvements in synoptic reporting utilization and national registries are needed to identity risk factors and reduce I-CRC frequency.  相似文献   
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