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161.
Hepatic and splenic sarcoidosis: Ultrasound and MR imaging   总被引:1,自引:0,他引:1  
Abdominal imaging studies may be performed for various indications in patients known to have sarcoidosis. To assess magnetic resonance imaging (MRI) and sonographic ability to detect abnormalities in sarcoidosis patients with abdominal involvement, a prospective study on 18 selected patients was performed. Besides organomegaly, when present, ultrasound demonstrated normal or increased hepatic parenchymal echogenicity, coarsening of the liver parenchyma with or without discrete nodules, focal calcifications, as well as contour irregularity. Splenic discrete nodules were seen on ultrasound in a single patient. Besides organomegaly, MRI abnormalities include abnormal hepatic signal intensity, discrete nodules, contour irregularity, spiculation of small hepatic vascular branches, and a high periportal signal intensity. MRI splenic abnormalities include contour irregularity, nodularity, and abnormal signal intensity.The data presented in this study reveals the spectrum of ultrasound and MRI findings in sarcoidosis patients with abdominal organ involvement, potentially enabling the evaluation of the severity of the disease. MRI appears more sensitive than ultrasound for study of abdominal sarcoidosis.  相似文献   
162.
OBJECTIVE: To characterize normal growth of the fetal fourth ventricle on ultrasonography throughout pregnancy. METHODS: Consecutive biometric measurements and fetal organ scans were obtained from 299 patients undergoing fetal anatomic surveys between 13 and 40 weeks' gestation. Using 7- and 3.5-MHz transducers for early (13- to 17-week) and late (>17-week) examinations, respectively, we scanned the fetal head in the axial plane with special focus on the posterior fossa of the brain. The fourth ventricle was identified, and its anteroposterior diameter and width were measured. A "triangle" formula was used for calculating its circumference and area. RESULTS: The fourth ventricle was shown as a hypoechoic triangle below the level of the cerebellum. A linear regression line of the fourth ventricle was observed across gestational age, and a first-degree correlation was found between gestational age and anteroposterior diameter of the fourth ventricle (r = 0.894; P < .0001; y = -0.84 + 0.23 x gestational age), its width (r = 0.657; P < .0001; y = 3.82 + 0.14 x gestational age), its circumference (r = 0.843; P < .0001; y = 5.11 + 0.58 x gestational age), and its area (r = 0.844; P < .0001; y = -10.11 + 1.17 x gestational age). Twelve enlarged fourth ventricles were found between 14 and 16 weeks, but results of follow-up scans at 20 weeks were normal. CONCLUSIONS: An isolated enlarged fourth ventricle in the early second trimester might represent a normal variant; it should be followed, but decisions about the fate of the pregnancy should not be based solely on this finding.  相似文献   
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164.
A convenient method is introduced for myocardial perfusion research by combining multislice short-axis cine cardiovascular magnetic resonance (MSA-CMR) and colored microspheres (CM). In canine control-ischemia-reperfusion (n = 11), Cardiac output (CO) was measured using MSA-CMR (COMSA), Phase Contrast CMR (PC-CMR, COPC) and CM (from reference blood samples, COmicro) in 3 experimental periods per animal. COmicro significantly and systematically overestimated COMSA (median deviation: 291 mL/min, p < 0.01), while there was excellent agreement between PC-CMR and MSA-CMR without significant over-or underestimation (median deviation: -14 ml/min, p = NS). In quantitative myocardial perfusion assay by CM, CMR should be used instead of reference blood sampling. This should improve the accuracy of absolute regional perfusion measurement.  相似文献   
165.
A qualitative analysis of the satisfaction of nurses with clinical decision making, the nature of the decision making, nurses' involvement in the process and factors that influence decision-making behavior is presented. The data were obtained from interviews conducted with physicians and nurses as a part of a study of nurse turnover and vacancy in hospitals. Staff nurse involvement in decision making is described as being interdependent; nurses reported general satisfaction with their involvement, while physicians generally resisted the decision-making discretion of nurses. Nurses on specialized and critical care units were more satisfied than were nurses who worked on general medical-surgical units. Trust and control were central issues. Implications for considering what knowledge, skill and decisional authority are needed for patient care are discussed.  相似文献   
166.
BACKGROUND: To investigate the potential use of Artificial Neural Network (ANN) in the evaluation of serum protein electrophoresis, we set up a multicenter study involving six Italian laboratories. For this purpose, we developed an algorithm named CASPER (Computer Assisted Serum Protein Electrophoresis Recognizer). METHODS: A total of 59,516 samples from the six centers were divided into three groups. Training and validation sets were used to develop the neural network, whereas evaluation set was used to test the performance of CASPER in recognizing abnormal electrophoretic profiles. RESULTS: CASPER showed 93.0% sensitivity and 47.4% specificity. CASPER sensitivity and specificity ranged in the six sites from 88% (site 3) to 97% (site 5) and from 36% (site 6) to 53% (site 3), respectively. Sensitivity for gamma zone was 94.6%, for beta zone 89.7% and for oligoclonal patterns 92.0%. CONCLUSIONS: The sensitivity of the CASPER algorithm does not allow us to recommend its use as a replacement for the visual inspection, but it could be helpful in avoiding accidental misclassifications by the operator. Moreover, the CASPER algorithm may be a useful tool for training operators and students. This study evidenced a high inter-observer variability, which should be addressed in a dedicated study. Data set to train and validate ANNs should contain a huge range and an adequate number of different abnormalities.  相似文献   
167.
OBJECTIVES: Intercellular adhesion molecule-1 (ICAM-1) plays a fundamental role during liver inflammation. In fact, weak ICAM-1 expression is physiologically restricted to the endothelium of portal vessels and to sinusoidal lining cells, but it becomes markedly evident on sinusoidal lining cells and at the surface of hepatocytes during inflammatory liver diseases. The aim of this study was to evaluate the behaviour of soluble ICAM-1 (sICAM-1) in chronic hepatitis C (CH-C) patients with persistently normal aminotransferase in comparison with patients with CH-C and elevated aminotransferase, and its changes during alpha-interferon (IFN) therapy. Immunohistochemical localization of ICAM-1 was also performed on liver tissue specimens of both groups. METHODS: Sixty subjects were divided into 3 groups: group A included 19 patients with CH-C and persistently normal aminotransferase; group B included 21 patients with CH-C and persistently elevated aminotransferase levels, and group C included 20 healthy subjects representing the control group. The first two groups were treated with recombinant alpha-IFN 2b at a dose of 6 MU 3 times a week for 3 months and followed up with 3 MU 3 times a week for another 3 months. RESULTS: Baseline values of serum ICAM-1 in groups A and B were significantly higher than those in group C (p < 0.0001). The median baseline value of sICAM-1 in group A (525.0 ng/ml) was lower than that of group B (561.0 ng/ml), but the difference was not statistically significant. Furthermore, there was a trend toward higher ICAM-1 values as histological severity increased (Mantel-Haenszel chi(2) 8.8, p < 0.003). Post-treatment sICAM-1 serum values showed a marked decrease in both groups, but only among responder patients, while ICAM-1 levels were unchanged in non-responders. Immunohistochemical localization showed no staining for ICAM-1 in normal liver specimens, while there was a quite similar staining for ICAM-1 in the two groups of patients, consistent with an inflammatory process. CONCLUSIONS: This study shows that circulating ICAM-1 levels in most patients with CH-C and persistently normal aminotransferase are higher than those in a control group and the fact that ICAM-1 molecules are also expressed on the hepatocyte membrane suggests that they could play an important role, in association with other molecules, in the intercellular adhesion processes during the induction and maintenance phases of the immune response. In both groups, only patients responding to alpha-IFN therapy showed a marked decrease in serum ICAM-1 below baseline values.  相似文献   
168.
PurposeTo determine long-term outcome in a cohort of children with newly diagnosed benign childhood epilepsy with centrotemporal spikes (BECTS).Methods29 children with BECTS were included in the Dutch Study of Epilepsy in Childhood. Each child was followed for 5 years, and subsequently contacted 12–17 years after enrolment to complete a structured questionnaire. Twenty children had typical BECTS, nine had atypical BECTS (age at onset <4 years, developmental delay or learning difficulties at inclusion, other seizure types, atypical EEG abnormalities).ResultsMean age at onset of epilepsy was 8.0 years with slight male preponderance. Most common seizure-types before enrolment were generalized tonic–clonic seizures (GTCS) and simple partial seizures; in 86% of the children seizures occurred during sleep. After 12–17 years, 96% had a terminal remission (TRF) of more than 5 years and 89% of more than 10 years. Mean duration of epilepsy was 2.7 years; mean age at reaching TRF was 10.6 years. Many children (63%) had experienced one or more (secondary) GTCS. Antiepileptic drugs were used by 79% of the children with a mean duration of 3.0 years. None of the children seemed to have developed learning problems or an arrest of cognitive development during follow-up. No significant differences were observed in patient characteristics or outcome between children with typical BECTS and children with atypical BECTS.ConclusionsAll children in our cohort, both those with typical and atypical BECTS, had a very good prognosis with high remission rates after 12–17 years. None of the predictive factors for disease course and outcome observed in earlier studies (other seizure types, age at onset, multiple seizures at onset) were prognostic in our cohort.  相似文献   
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170.
Talc is considered today as the agent of choice for pleurodesis, since it has a success rate of over 90%, depending on the application method used. Talc is a natural, asbestos-free product composed of talc, chlorite, and trace minerals. The powder is sprayed thoracoscopically on both pleural layers under visual control, whereas the slurry is instilled through the chest tube. Talc damages the mesothelial cells within 24 h. The resulting inflammation induces symphysis between the pleural layers. The application of talc has been widely studied; it is safe with rare adverse effects, widely available, and cost-efficient. This review gives an overview and offers tips and tricks for the use of talc as poudrage and slurry.  相似文献   
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