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131.
The acute toxicity of cylindrospermopsin (CYN) has been established in rodents, based on diverse intraperitoneal an oral exposure studies and more recently in fish. But no data have been reported in fish after subchronic exposure to cyanobacterial cells containing this cyanotoxin, so far. In this work, tilapia (Oreochromis niloticus) were exposed by immersion to lyophilized Aphanizomenon ovalisporum cells added to the aquaria using two concentration levels of CYN (10 or 100 μg CYN L?1) and deoxy‐cylindrospermopsin (deoxy‐CYN) (0.46 or 4.6 μg deoxy‐CYN L?1), during two different exposure times: 7 or 14 d. This is the first study showing damage in the liver, kidney, hearth, intestines, and gills of tilapia after subchronic exposure to cyanobacterial cells at environmental relevant concentrations. The major histological changes observed were degenerative processes and steatosis in the liver, membranous glomerulopathy in the kidney, myofibrolysis and edema in the heart, necrotic enteritis in the gastrointestinal tract, and hyperemic processes in gill lamellae and microhemorrhages. Moreover, these histopathological findings confirm that the extent of damage is related to the CYN concentration and length of exposure. Results from the morphometric study indicated that the average of nuclear diameter of hepatocytes and cross‐sections of proximal and distal convoluted tubules are useful to evaluate the damage induced by CYN in the main targets of toxicity. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 261–277, 2015.  相似文献   
132.
Curve of left ventricular (LV) volume changes throughout the cardiac cycle is a fundamental parameter for clinical evaluation of various cardiovascular diseases. Currently, this evaluation is often performed manually which is tedious and time consuming and suffers from significant interobserver and intraobserver variability. This paper introduces a new automatic method, based on nonlinear dimensionality reduction (NLDR) for extracting the curve of the LV volume changes over a cardiac cycle from two-dimensional (2-D) echocardiography images. Isometric feature mapping (Isomap) is one of the most popular NLDR algorithms. In this study, a modified version of Isomap algorithm, where image to image distance metric is computed using nonrigid registration, is applied on 2-D echocardiography images of one cycle of heart. Using this approach, the nonlinear information of these images is embedded in a 2-D manifold and each image is characterized by a symbol on the constructed manifold. This new representation visualizes the relationship between these images based on LV volume changes and allows extracting the curve of the LV volume changes automatically. Our method in comparison to the traditional segmentation algorithms does not need any LV myocardial segmentation and tracking, particularly difficult in the echocardiography images. Moreover, a large data set under various diseases for training is not required. The results obtained by our method are quantitatively evaluated to those obtained manually by the highly experienced echocardiographer on ten healthy volunteers and six patients which depict the usefulness of the presented method.  相似文献   
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目的:探讨和研究孤独症患儿对5种基本面部表情的认知特征。方法研究对象选取2014年1月~2014年12月被诊断为孤独症的46例患儿,设为观察组,选取基本情况与观察组匹配的100例正常儿童作为对照组,2组儿童分别被动观察高兴、悲伤、惊讶、愤怒、恐惧5种面部基本表情图,对比2组患者的视觉注意行为和自身情绪变化。结果视觉注意行为结果显示,观察组患儿对5种情绪的初次平均注视时间均显著低于对照组(P<0.05),且对5种情绪的回看次数也显著低于对照组(P<0.05);情绪反应结果显示,孤独症患儿的悲伤、惊讶、愤怒、恐惧的积极反应评分均高于对照组(P<0.05),高兴、悲伤、惊讶的消极反应评分均高于对照组(P<0.05),其他对比差异无统计学意义。结论孤独症患儿对于面部表情的视觉注意减少,存在一定程度的情绪感知缺陷,对于负性情绪的理解相对更为困难,应当引起临床关注。  相似文献   
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137.

Context

Studies on multiple dimensions of the symptom experience of patients with gastrointestinal cancers are extremely limited.

Objective

Purpose was to evaluate for changes over time in the occurrence, severity, and distress of seven common symptoms in these patients.

Methods

Patients completed Memorial Symptom Assessment Scale, six times over two cycles of chemotherapy (CTX). Changes over time in occurrence, severity, and distress of pain, lack of energy, nausea, feeling drowsy, difficulty sleeping, and change in the way food tastes were evaluated using multilevel regression analyses. In the conditional models, effects of treatment group (i.e., with or without targeted therapy), age, number of metastatic sites, time from cancer diagnosis, number of prior cancer treatments, cancer diagnosis, and CTX regimen on enrollment levels, as well as the trajectories of symptom occurrence, severity, and distress were evaluated.

Results

Although the occurrence rates for pain, lack of energy, feeling drowsy, difficulty sleeping, and change in the way food tastes declined over the two cycles of CTX, nausea and numbness/tingling in hands/feet had more complex patterns of occurrence. Severity and distress ratings for the seven symptoms varied across the two cycles of CTX.

Conclusions

Demographic and clinical characteristics associated with differences in enrollment levels as well as changes over time in occurrence, severity, and distress of these seven common symptoms were highly variable. These findings can be used to identify patients who are at higher risk for more severe and distressing symptoms during CTX and to enable the initiation of preemptive symptom management interventions.  相似文献   
138.
Hepatitis C virus (HCV) chronic infection is associated with fibrosis progression, end-stage liver complications and HCC. Not surprisingly, HCV infection is a leading cause of liver-related morbidity and mortality worldwide. After sustained virological response (SVR), the risk of developing hepatocellular carcinoma is not completely eliminated in patients with established cirrhosis or with advanced fibrosis. Therefore, lifelong surveillance is currently recommended. This strategy is likely not universally cost-effective and harmless, considering that not all patients with advanced fibrosis have the same risk of developing HCC. Factors related to the severity of liver disease and its potential to improve after SVR, the molecular and epigenetic changes that occur during infection and other associated comorbidities might account for different risk levels and are likely essential for identifying patients who would benefit from screening programs after SVR. Efforts to develop predictive models and risk calculators, biomarkers and genetic panels and even deep learning models to estimate the individual risk of HCC have been made in the direct-acting antiviral agents era, when thousands of patients with advanced fibrosis and cirrhosis have reached SVR. These tools could help to identify patients with very low HCC risk in whom surveillance might not be justified. In this review, factors affecting the probability of HCC development after SVR, the benefits and risks of surveillance, suggested strategies to estimate individualized HCC risk and the current evidence to recommend lifelong surveillance are discussed.  相似文献   
139.
To evaluate hepatic expression of the nuclear proliferative marker Ki-67 and the p53 oncoprotein in hepatitis B virus (HBV)/HCV cirrhosis in relation to dysplastic liver cell changes and hepatocellular carcinoma (HCC). We studied needle liver biopsies from 107 patients with cirrhosis and no HCC (52 HBV, 55 HCV) who had been assessed for protocol studies, and 57 cirrhotic patients with HCC (40 HBV, 17 HCV). We evaluated small and large cell dysplastic changes along with the expression of Ki-67 and p53 by immunohistochemistry. The labelling index (LI) was defined as the proportion (%) of positive-stained nuclei of the 500 measured. Large and small cell dysplastic changes were observed in 12 and 9% of specimens respectively. Only small cell changes were associated with Ki-67 expression. Ki-67 LI was 5.50 +/- 5.7 in cirrhosis (13.90 +/- 3.84 in those with small cell dysplastic changes vs 4.64 +/- 4.98 in those without, P < 0.01), 10.2 +/- 5.95 in cirrhosis with HCC (P < 0.05) and 18.56 +/- 10 in HCC (P < 0.01). Neither the presence of small cell dysplastic changes nor the expression of Ki-67 was related to severity or aetiology of cirrhosis. Expression of p53 was observed in 30% of the non-tumorous and in 53% of the neoplastic tissue obtained from patients with HCC, with no differences between HCV and HBV. Ki-67 and p53 expression was associated with the tumour grade (P < 0.001). Our observations clearly demonstrate the association between the proliferation activity and the morphological changes in the cirrhotic liver from the non-dysplastic to dysplastic lesion to HCC. They also support the hypothesis that p53 alterations are a rather late event in carcinogenesis and related to HCC grade. And finally, they suggest that the final steps of hepatocarcinogenesis are common and independent of the aetiology of the chronic viral infection.  相似文献   
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