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Enterocytozoon bieneusi is an agent of intestinal microsporidiosis leading to chronic diarrhoea in AIDS patients. Pulmonary involvement may occur but remains rare with only 4 cases reported in the literature. We report here the fifth case of pulmonary localization of E. bieneusi in a severe immunocompromized HIV-infected patient with intestinal and pulmonary symptoms.  相似文献   
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OBJECTIVES: A relationship between chronic hepatitis C virus (HCV) infection and lipid metabolism has recently been suggested. The aim of this study was to determine the correlation between lipid profile and virology, histologic lesions, and response to alpha interferon therapy in noncirrhotic, nondiabetic patients with hepatitis C. METHODS: A total of 109 consecutive untreated chronic hepatitis C patients were studied to assess the following: 1) the effects of HCV genotype, viral load, steatosis, hepatic fibrosis, and body mass index (BMI) on lipid profile; and 2) whether lipid parameters could predict response to antiviral therapy. RESULTS: The control group showed a significantly higher apolipoprotein B (apoB) concentration compared with patients with chronic hepatitis C. Hypobetalipoproteinemia (apo B <0.7 g/L) was found in 27 (24.7%) chronic HCV patients and in five (5.3%) control subjects (p = 0.0002). Levels of apo B were negatively correlated with steatosis and HCV viral load (r = -0.22; p = 0.03). This last correlation was strong for non-1 genotype and genotype 3 (r = -0.48; p = 0.0005, and r = -0.47; p = 0.007, respectively) but was not found in genotype 1. In multivariate analysis, low apo B concentration was significantly associated with fibrosis grade 2 or 3 versus grade 0 or 1 (p < 0.001), steatosis >5% (p < 0.001), low body mass index (p < 0.001), and high HCV viral load (p < 0.014). No correlation was found in the 76 treated patients between apo B and response to interferon therapy. CONCLUSIONS: In chronic HCV patients, hypobetalipoproteinemia occurs already in the early stages of HCV infection before the development of liver cirrhosis. The correlation between apo B levels and HCV viral load seems to confirm the interaction between hepatitis C infection and beta-lipoprotein metabolism.  相似文献   
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The results of work by several investigators indicate that crossbridge attachment serves as a positive feedback mechanism that transiently increases the Ca2+ affinity of troponin C (TnC) during each normal heartbeat. To monitor structural changes in the cardiac isoform of TnC (cTnC) associated with Ca2+ binding and crossbridge attachment in muscle, we labeled cTnC with the sulfhydryl-specific fluorescent probe 2-(4'-iodoacetamidoanilino)naphthalene-6-sulfonic acid (IAANS). When IAANS-labeled cTnC (cTnCIAANS) was substituted for endogenous TnC, the fluorescence intensity of cardiac and skeletal muscle preparations increased substantially during rigor crossbridge attachment in the absence of Ca2+ (pCa 9.2). In cardiac muscle, the fluorescence signal increased the same amount in rigor and maximal activation, whereas in skeletal muscle, it was higher in rigor (rigor: cardiac and skeletal = 1; pCa 4.0: cardiac = 0.98 +/- 0.13, skeletal = 0.59 +/- 0.05). This indicates that crossbridge attachment alone is capable of influencing the structure of cTnCIAANS. Because the relative fluorescence intensity of cTnCIAANS was more sensitive to Ca2+ than was force in both preparations (cardiac: pCa50 fluorescence = 6.05 +/- 0.05, pCa50 force = 5.51 +/- 0.11; skeletal: pCa50 fluorescence = 5.94 +/- 0.13, pCa50 force = 5.65 +/- 0.14), we measured the Ca2+ sensitivity of the strong crossbridge attachment (sinusoidal stiffness was measured by imposing 1 kHz at 0.1-0.2% muscle length) in rat trabeculae.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Bone mineral density and bone turnover in spinal osteoarthrosis.   总被引:1,自引:2,他引:1       下载免费PDF全文
OBJECTIVES--To determine whether there was a generalised increase in bone mineral density (BMD) in spinal osteoarthrosis (OA), and to determine the mechanism of this possible protection against osteoporosis as assessed by biochemical markers of bone turnover. METHODS--We studied 375 women (ages 50 to 85) from a population based group. Spinal OA was defined from radiographs as the presence of degenerative changes affecting intervertebral or facet joints. BMD of the lumbar spine (LS), femoral neck (FN) and total body (TB) was measured by dual energy x ray absorptiometry (Lunar DPX). Bone turnover rates were estimated from measurement of biochemical markers of bone formation and resorption (urine deoxypyridinoline (Dpyr) and serum bone specific alkaline phosphatase (BAP)). RESULTS--BMD at each site was greater in the women with spinal OA (mean increase in LS-BMD 7.9%, 95% confidence interval (CI) 1.0 to 15.1; TB-BMD 8.4%, 95% CI 1.9 to 9.7; FN-BMD 6.4%, 95% CI 0.3 to 12.6). Twenty four hour urinary excretion of Dpyr, corrected for TB bone mineral content, and serum BAP were 19% lower in the women with spinal OA (95% CI for Dpyr 4.3 to 31.9%; for BAP 6.3 to 32.0%). CONCLUSIONS--Spinal OA is associated with a generalised increase in BMD and a decreased rate of bone turnover. This suggests that the protective effect of spinal OA against osteoporosis may be mediated by decreased bone turnover.  相似文献   
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Acute intermittent porphyria is an autosomal dominant inherited disorder resulting from a deficiency of porphobilinogen deaminase activity, the third enzyme in the heme biosynthesis pathway. This disease is uncommon, although the prevalence is higher in asymptomatic heterozygotic carriers; however, this prevalence is difficult to establish because of the absence of symptoms. Although acute intermittent porphyria is a multisystemic disease, its most common form of presentation is abdominal pain and neurological or mental symptoms, which can sometimes be due to precipitating factors such as reduced energy intake, smoking, alcohol, some drugs, and stress. Diagnosis can be made by testing urinary porphobilinogen levels, with subsequent measurement of enzyme activity and DNA testing. Treatment is based on prevention of porphyria attacks by avoiding precipitating factors and early administration of intravenous glucose or hemin therapy. We present the case of a patient diagnosed with acute intermittent porphyria based on study of chronic mild alanine aminotransferase (ALT) elevation.  相似文献   
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OBJECTIVE: To assess the effects of delirium on the institutionalization rate, taking into account geriatric syndromes and nutritional status. METHODS: This population-based study took place in an acute care unit and included participants older than 75 years, arriving from home and later discharged. Confusion Assessment Method (CAM) symptoms were recorded by the nurses within 24 hours after admission and every 3 days. Delirium was defined using the CAM algorithm, and subsyndromal delirium responded to symptoms not fulfilling the CAM algorithm. These delirium categories were either present at admission (prevalent) or occurred during the hospital stay (incident). Participants were classified as having a low dietary intake when energy intake was at any time lower than 600 kcal/d. Age, sex, known cognitive impairment, weight, functional dependency, and laboratory testing as well as diagnoses were also recorded. Step-by-step backward logistic regression was used to identify predictors of institutionalization. RESULTS: Among 427 patients, 310 (72.6%) were discharged and were compared with 117 (27.4%) participants admitted to an institution. Female sex (odds ratio [OR]: OR 2.15, 95% confidence interval [CI]: CI 1.22-3.78), prevalent delirium (OR 3.19, 95% CI 1.33-7.64), subsyndromal delirium (OR 2.72, 95% CI 1.48-5.01), incident subsyndromal delirium (OR 4.27, 95% CI 2.17-8.39), low dietary intake (OR 2.50, 95% CI 1.35-4.63), and a fall (OR 2.16, 95% CI 1.22-3.84) or a diagnosis of stroke (OR 2.03, 95% CI 1.04-3.94) were independent predictors of institutionalization. CONCLUSIONS: Symptoms of delirium and severe nutritional impairment led patients to geriatric institutions. Therefore, these institutions need to implement policies that address both of these issues.  相似文献   
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