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41.
42.
Recently, exercise-induced spastic coronary artery occlusion at the site of moderate stenosis, which Prinzmetal’s angina or cardiac syndrome X does not cover, was reported. Multi-modality imaging is important for the diagnosis of coronary artery disease with a complex ischemic mechanism. However, the previous report did not include findings from intracoronary imaging at the site of moderate coronary stenosis. We report a case of exercise-induced vasospastic angina at the site of moderate stenosis, where multi-modality imaging, including exercise stress echocardiography and intravascular ultrasound, was utilized to make a definitive diagnosis and investigate underlying causes.  相似文献   
43.
N-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) have protective effects against atherosclerosis. Monocyte chemotactic protein (MCP)-1 is a major inflammatory mediator in the progression of atherosclerosis. However, little is known about the regulation of Mcp-1 by DHA and EPA in vessels and vascular smooth muscle cells (VSMCs). In this study, we compared the effect of DHA and EPA on the expression of Mcp-1 in rat arterial strips and rat VSMCs. DHA, but not EPA, suppressed Mcp-1 expression in arterial strips. Furthermore, DHA generated 4-hydroxy hexenal (4-HHE), an end product of n-3 polyunsaturated fatty acids (PUFAs), in arterial strips as measured by liquid chromatography-tandem mass spectrometry. In addition, 4-HHE treatment suppressed Mcp-1 expression in arterial strips, suggesting 4-HHE derived from DHA may be involved in the mechanism of this phenomenon. In contrast, Mcp-1 expression was stimulated by DHA, EPA and 4-HHE through p38 kinase and the Keap1-Nuclear factor erythroid-derived 2-like 2 (Nrf2) pathway in VSMCs. In conclusion, there is a dual effect of n-3 PUFAs on the regulation of Mcp-1 expression. Further study is necessary to elucidate the pathological role of this phenomenon.  相似文献   
44.
Caspase-3 is a major cell death effector protease in the adult and neonatal nervous system. We found a greater number and higher density of cells in the cortex of caspase-3(-/-) adult mice, consistent with a defect in developmental cell death. Caspase-3(-/-) mice were also more resistant to ischemic stress both in vivo and in vitro. After 2 h of ischemia and 48 h of reperfusion, cortical infarct volume was reduced by 55%, and the density of terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling-positive cells was decreased by 36% compared with wild type. When subjected to oxygen-glucose deprivation (2 h), cortical neurons cultured from mice deficient in caspase-3 expression were also more resistant to cell death by 59%. Mutant brains showed caspase-specific poly(ADP-ribose) polymerase cleavage product (85-kDa fragment) in vivo and in vitro, suggesting redundant mechanisms and persistence of caspase-mediated cell death. In the present study, we found that caspase-8 mediated poly(ADP-ribose) polymerase cleavage in caspase-3(-/-) neurons in vivo and in vitro. In addition, mutant neurons showed no evidence of compensatory activation by caspase-6 or caspase-7 after ischemia. Taken together, these data extend the pharmacological evidence supporting an important role for caspase-3 and caspase-8 as cell death mediators in mammalian cortex and indicate the potential advantages of targeting more than a single caspase family member to treat ischemic cell injury.  相似文献   
45.
Serum NSE levels were measured in 126 patients with previously untreated NSCLC. The NSE level was greater than 10 ng/ml in 29 patients (23.0%) and this was considered to be positive. Elevation of serum NSE levels correlated closely with clinical stage except stage I and II. The effect of chemotherapy was evaluated in 74 cases included 22 NSE-positive cases. The response rate was 50% in positive cases and 34.6% in negative cases. However, the median duration of response in positive cases (2.2 months) was significantly shorter than that in negative cases (6.6 months). The median survival time of 6.0 months in positive cases was brief compared with 9.6 months in negative cases. These results indicate that elevation of serum NSE level in patients with NSCLC may be a marker of poor prognosis.  相似文献   
46.

BACKGROUND:

Angiocardiography is an important diagnostic modality for evaluation of heart disease. It is well known that the concentration of plasma atrial natriuretic peptide (ANP) increases after injection of contrast medium. On the other hand, some patients with hypertension, heart failure or cardiac hypertrophy have an increased plasma ANP concentration at baseline; however, whether ANP increases after angiography in these patients is unknown.

OBJECTIVES:

To investigate changes in plasma ANP concentrations after angiocardiography in patients with high ANP concentrations at baseline.

PATIENTS AND METHODS:

Plasma ANP concentrations of 32 patients with angina pectoris were measured before and after angiocardiography. They were then classified into two groups according to their ANP concentration before examination.

RESULTS:

ANP concentration after the injection of contrast medium increased significantly in patients with normal ANP concentrations before angiography but did not change in patients with high ANP concentrations at rest.

CONCLUSIONS:

These results suggest that the absence of an increase in ANP after angiography may in part be due to reduced sensitivity to the angiography stimulus or to an already maximal activation of ANP secretion at baseline.  相似文献   
47.
Summary. We report the case of a 2-year-old Japanese boy with acute favism who was treated with human haptoglobin products. He had been exhibiting chronic nonspherocytic haemolytic anaemia until the diagnosis of glucose-6-phosphate dehydrogenase (G6PD) deficiency when 14 months old. He suffered a favic crisis at 24 months of age, when the administration of haptoglobin was effective for relieving bilirubinaemia and haemoglobinuria. Serum-free Hb rapidly decreased to normal levels despite the sustained level of serum lactate dehydrogenase. His G6PD gene was G6, Guadalajara. This is the first application of haptoglobin therapy for acute favism and the first reported case of Japanese G6PD deficiency with typical favic crisis. Haptoglobin treatment might be helpful for managing the haemolytic crisis in the disease.  相似文献   
48.
Localization of increased hepatic vascular resistance in liver cirrhosis   总被引:5,自引:0,他引:5  
To determine the localization of increased vascular resistance in cirrhotic liver, blood pressures were measured by a direct cannulation method at several key points in the hepatic vascular pathway in normal and cirrhotic rats. Cirrhosis was produced by feeding a choline-deficient diet. Blood pressures in normal rats were 110 mm H2O in the portal vein, 68 mm H2O in the terminal portal venule, 28 mm H2O in the terminal hepatic venule and 20 mm H2O in the inferior vena cava. In cirrhotic rats, blood pressures in the portal vein and the terminal portal venule were 173 and 100 mm H2O, respectively, while those in the terminal hepatic venule and the inferior vena cava were elevated only slightly above normal. These hemodynamic data suggest that an increase in vascular resistance in cirrhotic liver is present in the intrahepatic portal vein and sinusoids, but not in intrahepatic hepatic vein. In cirrhotic liver, stenosis and distortion were found in peripheral branches of the portal vein, and sinusoidal stenoses and a decrease in sinusoidal space were recognized. Accordingly, it is suggested that the increase in vascular resistance in the intrahepatic portal vein and sinusoids correlate with these structural changes. Although severe stenoses and distortion were found in hepatic vein branches, it was thought that they do not contribute to portal hypertension because of lack of increase in vascular resistance in the intrahepatic hepatic vein.  相似文献   
49.
This study was conducted to clarify the characteristics of colestimide responders. Forty-seven non-diabetic patients with high levels of low-density lipoprotein cholesterol (LDL-C) received colestimide at 3,000 mg/day and were followed up for 4 months. After 4 months, body weight was reduced but the change was not statistically significant. Total serum cholesterol (TC) and LDL-C levels significantly decreased from 280 to 232 mg/dl and from 195 to 150 mg/dl, respectively (p<0.01 versus before colestimide was administered). Serum triglyceride (TG) levels increased, but the change was not significant. Preheparin lipoprotein lipase mass (preheparin LPL mass) at baseline was significantly higher in colestimide responders (greater than a 20% decrease of LDL-C: n=28) than non-responders (76.2 ng/ml versus 50.3 ng/ml, p<0.05: n=19). Next, the subjects were divided into those with a high (n=33) and low (n=14) preheparin LPL mass at baseline. LDL-C levels were significantly decreased in patients with a high preheparin LPL mass while TG levels were significantly increased in patients with a low preheparin LPL mass. These results suggest that baseline preheparin LPL mass may be a marker of the response to colestimide.  相似文献   
50.
Objective: The purpose of this study was to assess scrum type IV collagen 7-S domain (IV 7-S) levels in colorectal cancer patients with hepatic metastasis and to investigate the relation between serum IV 7-S levels and type IV collagenase activities in tumor tissue. Methods: Tissue type IV collagena.se activity and serum IV 7-S were measured in 50 colorectal cancer patients without hepatic metastasis and in 26 patients with hepatic metastasis. Results: Type IV collagenase showed significantly higher activities in colorectal cancer (n = 36) than in colorectal normal mucosa (n = 36) ( p < 0.001), but significantly lower activities were shown in the hepatic metastatic tumor (n = 18) than in the primary tumor (n = 36) and normal liver tissue (n = 18) ( p < 0.001). No significant correlation was (bund between type IV collagenase activities in the tumor and serum IV 7-S levels. Colorectal cancer patients with hepatic metastasis (n = 26) had significantly higher serum IV 7-S levels than those without hepatic metastasis (n = 50) ( p < 0.001). Moreover, serum IV 7-S levels correlated significantly with hepatic metastatic tumor volume in patients with synchronous ( r = 0.719, p < 0.001, n = 26) and in patients with metachronous ( r = 0.910, p < 0.001, n = 16) hepatic metastasis. Conclusion: We suggest that serum IV 7-S levels may increase in hepatic metastasis, not by the degradation of type IV collagen in the primary and secondary tumors, but by the enhanced production of type IV collagen responsive to hepatic metastasis. The measurement of serum IV 7-S levels might be a useful tumor marker of hepatic metastasis reflecting hepatic metastatic tumor volume.  相似文献   
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