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71.
To identify neuroimaging biomarkers of alcohol dependence (AD) from structural magnetic resonance imaging, it may be useful to develop classification models that are explicitly generalizable to unseen sites and populations. This problem was explored in a mega-analysis of previously published datasets from 2,034 AD and comparison participants spanning 27 sites curated by the ENIGMA Addiction Working Group. Data were grouped into a training set used for internal validation including 1,652 participants (692 AD, 24 sites), and a test set used for external validation with 382 participants (146 AD, 3 sites). An exploratory data analysis was first conducted, followed by an evolutionary search based feature selection to site generalizable and high performing subsets of brain measurements. Exploratory data analysis revealed that inclusion of case- and control-only sites led to the inadvertent learning of site-effects. Cross validation methods that do not properly account for site can drastically overestimate results. Evolutionary-based feature selection leveraging leave-one-site-out cross-validation, to combat unintentional learning, identified cortical thickness in the left superior frontal gyrus and right lateral orbitofrontal cortex, cortical surface area in the right transverse temporal gyrus, and left putamen volume as final features. Ridge regression restricted to these features yielded a test-set area under the receiver operating characteristic curve of 0.768. These findings evaluate strategies for handling multi-site data with varied underlying class distributions and identify potential biomarkers for individuals with current AD.  相似文献   
72.
Herein we report a patient who was initially thought to have renal arteriovenous fistulas 3 months after laparoscopic partial nephrectomy for a small renal mass. After timely intervention using selective renal artery embolization, computed tomography 9 months post‐surgery showed persistent renal arteriovenous fistulas and nodular lesions in the perirenal fat. The patient then underwent radical nephrectomy, and histopathological examination showed underlying recurrent clear cell renal cell carcinoma invading the intraparenchymal arteries and veins, which was simulating multiple high‐flow renal arteriovenous fistulas.  相似文献   
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74.
Obesity Surgery - This study aims to examine the predictive role of obesity-type-related indexes and perioperative intraabdominal pressure measurements for early postoperative complications...  相似文献   
75.
Adrenaline, which is released from the adrenal medulla, is an important compound in the reaction of sympathetic nerve system. This hormone can increase the body’s normal metabolic rate up to 100 %, and thus improves the effectiveness of the whole body. It has been considered to be involved in the control of inflammation. Therefore, we investigated whether there are effects of paracetamol and etodolac on adrenaline levels of rats after oral administration. The rats were divided into three subgroups while analysing the effects of adrenaline on paracetamol and etodolac. The first group was the control, second group was composed of rats given paracetamol, and third group was composed of rats given etodolac. In order to measure adrenaline plasma concentration, we have used the high-performance liquid chromatography coupled with fluorescence detection. According to the result of the analysis, there are statistically important differences at adrenaline levels between control group and rats-applied drugs. Obtained results showed that although adrenaline level in the paracetamol-applied group decreased, adrenaline level in the etodolac-applied group increased. It is concluded that different effects of etodolac and paracetamol on circulating adrenaline levels can be related to their different effects on inflammation, COX enzymes, prostaglandins, etc. Also we can suggest usage of paracetamol instead of etodolac in patients with cardiovascular system diseases.  相似文献   
76.
The aim of this study is to assess the biomechanical advantage of adding strut allograft and the effect of its position on the construct in Vancouver type B1 fractures. Fifteen forth-generation synthetic femurs were used and created a fracture model at the tip of prosthesis, and subsequently fixated with a lateral plate only, lateral plate and medial strut, lateral plate and anterior strut. Rotational and axial tests were performed. In all loading tests, the plate with medial strut group was stiffer than the other constructs and had higher failure load values and had less displacement in the fracture site. A combination of a plate with a medial strut allograft provides more mechanical stability on periprosthetic femoral fractures near the tip of a total hip arthroplasty.  相似文献   
77.
Behcet’s disease (BD) is a rare chronic, relapsing, multisystemic disorder characterized by mucocutaneous, ocular, vascular and central nervous system manifestations. However, the etiopathogenesis of the disease remains unknown, and diagnosis is basically dependent on clinical manifestations. Sometimes BD may be diagnosed with rare clinical entities. Herein, we presented an extremely rare case of urethrovaginal fistula which has been diagnosed as manifestation of BD. After surgical treatment of fistula, there was no complication in 6 months following surgical repair and the follow-up period has been going on.  相似文献   
78.

Background and Objectives:

Bowel anastomosis after anterior resection is one of the most difficult tasks to perform during laparoscopic colorectal surgery. This study aims to evaluate a new feasible and safe intracorporeal anastomosis technique after laparoscopic left-sided colon or rectum resection in a pig model.

Methods:

The technique was evaluated in 5 pigs. The OrVil device (Covidien, Mansfield, Massachusetts) was inserted into the anus and advanced proximally to the rectum. A 0.5-cm incision was made in the sigmoid colon, and the 2 sutures attached to its delivery tube were cut. After the delivery tube was evacuated through the anus, the tip of the anvil was removed through the perforation. The sigmoid colon was transected just distal to the perforation with an endoscopic linear stapler. The rectosigmoid segment to be resected was removed through the anus with a grasper, and distal transection was performed. A 25-mm circular stapler was inserted and combined with the anvil, and end-to-side intracorporeal anastomosis was then performed.

Results:

We performed the technique in 5 pigs. Anastomosis required an average of 12 minutes. We observed that the proximal and distal donuts were completely removed in all pigs. No anastomotic air leakage was observed in any of the animals.

Conclusion:

This study shows the efficacy and safety of intracorporeal anastomosis with the OrVil device after laparoscopic anterior resection.  相似文献   
79.
80.
OBJECTIVE: Postural phenomena, cardiac arrhythmias and autonomic dysfunction are responsible for presyncope and syncope in patients with mitral valve prolapse (MVP). In this study, arrhythmia and vasovagal syncope incidence were investigated in children with MVP. METHODS: Between April 2005 and December 2006, 37 children with MVP and 26 healthy children were evaluated.Telecardiography, electrocardiography (ECG), echocardiography, Holter monitoring, exercise test and head-up tilt test were performed. RESULTS: The MVP group consisted of 19 boys and 18 girls with a mean age of 11.8 years. The control group was similar with respect to age and gender. Telecardiography, ECG, Holter monitoring, exercise test and QTc of all children were within normal limits.There was a statistically significant difference between the two groups in terms of QT dispersion. The tilt table test was positive in 11 of 37 (29.7%) children with MVP and in 1 of 26 (3.8%) normal healthy children. This difference was statistically significant (P < 0.01). CONCLUSION: Arrhythmia and syncope frequency was found to be higher in children with MVP than in the normal population. The risk of vasovagal syncope indicated by a positive tilt test was found to be increased in children with MVP. Therefore, patients and families must be informed about the conditions that may predispose to vasovagal syncope and caution should be recommended in these patients.  相似文献   
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