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41.
42.
Effect of HCV NS3 protein on P53 protein expression in hepatocarcinogenesis   总被引:14,自引:0,他引:14  
NTRODUCTIONHepatocelularcarcinoma(HCC)isoneofthemostcommonhumancancersintheworld.Recently,theHCVinfectionwasfoundtobeanetiolo...  相似文献   
43.
NTRODUCTIONApoptosisisanimportantphysiologicalformofceldeath.Itisstrictlycontroledbygenes.Ithasbeenshowninexperimentsthatexte...  相似文献   
44.
OBJECTIVES: To develop an automated imaging assessment tool that accommodates the anatomic variability of the elderly and demented population as well as the registration errors occurring during spatial normalization. METHODS: 20 subjects with Alzheimer's disease (AD), mild cognitive impairment, or normal cognition underwent MRI brain imaging and had their 3D volumetric datasets manually partitioned into 68 regions of interest (ROI) termed sub-volumes. Gray matter (GM), white matter (WM), and cerebral spinal fluid (CSF) voxel counts were then made in the subject's native space for comparison against automated volumetric measures within three sub-volume probabilistic atlas (SVPA) models. The three SVPAs were constructed using 12 parameter affine (12 p), 2nd order (2nd), and 6th order (6th) transforms derived from registering the manually partitioned scans into a Talairach compatible AD population-based target. The three SVPA automated measures were compared to the manually derived measures in the 20 subjects' native space with a "jack-knife" procedure in which each subject was assessed by an SVPA they did not contribute toward constructing. RESULTS: The mean left and right GM ratio (GM ratio = [GM + CSF] / CSF) "r values" for the 3 SVPAs compared to the manually derived ratios across the 68 ROIs were 0.85 for the 12p SVPA, 0.88 for the 2nd SVPA, and 0.89 for the 6th SVPA. The mean left and right WM ratio (WM ratio = [WM + CSF] / CSF) "r values" for the 3 SVPAs being 0.84 for the 12p SVPA, 0.86 for the 2nd SVPA, and 0.88 for the 6th SVPA. CONCLUSION: We have constructed, from an elderly and demented cohort, an automated brain volumetric tool that has excellent accuracy compared to a manual gold standard and is capable of regional hypothesis testing and individual patient assessment compared to a population.  相似文献   
45.
The purpose of this quasi-experimental (pre- and posttest) study was to test a model pain management program (PMP) to implement the American Pain Society (APS) quality assurance standards for the management of acute and chronic cancer pain using a continuous quality improvement (CQJ) approach to improve professionals' knowledge and skills, patient satisfaction, and to identify areas needing improvement. The sample consisted of 1210 nurse responses and 698 interviews of patients with pain during hospitalization at a major urban cancer center. The PMP provided a structure (standards), educational opportunities, and training in CQI methods. Outcome measures included a patient evaluation questionnaire and concerns checklist: nurse knowledge, attitude and barriers questionnaire; and focus groups to identify areas needing improvement. Significant improvements were found in patients' satisfaction, nurses' knowledge and attitude scores, and reductions in nurses' perceptions of barriers. Focus groups revealed the need for improved communication among disciplines about pain and better assessment of patients unable to self-report. The program met its goal of implementing the APS standards, educating nurses, and identifying “system” problems, and improving overall patient satisfaction.  相似文献   
46.
Purpose  The survival of patients with hepatocellular carcinoma (HCC) has been prolonged with improvements in various diagnostic tools and treatment modalities. Consequently, bone metastases from HCC are diagnosed more frequently. We investigated the clinical features, prognosis, treatment outcomes, and prognostic factors of HCC presenting with bone metastasis. Methods  Between June 2000 and April 2007, we recruited 37 consecutive HCC patients presenting with bone metastasis. These patients were divided into an untreated control group (n = 16) and a treated group (n = 21). Results  The mean age of the patients was 61.1 years (male:female, 31:6). The most common cause of HCC was hepatitis B virus infection (56.8%). Twenty-two patients (59.5%) were of Child-Pugh class A and 15 (40.5%) were of Child-Pugh class B. Spinal metastasis was most common and noted in 21 patients (56.7%). The treatment modalities in the treated group included intra-arterial chemotherapy in nine patients (42.8%), systemic chemotherapy in five (23.8%), and both intra-arterial and systemic chemotherapy in seven (33.4%). The median survival of all patients was 6.2 months (range 0.7–46.6); that of untreated control group and the treated group was 2.9 (range 0.7–42.2) and 9.7 (range 0.9–46.6) months, respectively, with no significant difference (log-rank test, = 0.081). Cox regression analysis revealed that the presence of ascites at the initial presentation was the only prognostic factor (= 0.016). Conclusion  Although our study showed that locoregional and/or systemic chemotherapy did not provide significant survival prolongation compared to supportive care in patients with HCC initially accompanied by bone metastasis, a more large-scaled randomized study might be required. S. U. Kim and D. Y. Kim have equally contributed to this work.  相似文献   
47.
A biloma is an encapsulated bile collection outside the biliary tree. Most cases of biloma are caused by iatrogenic injury or trauma. Intrahepatic rupture of the biliary tree due to nontraumatic cause is a rare event. A 68- year-old man was admitted because of abdominal pain and fever. He had no past history of abdominal surgery, instrumentation or trauma. Computed tomography (CT) scan and magnetic resonance cholangiopancreatography (MRCP) demonstrated a large subcapsular fluid collection in the right liver associated with choledocholithiasis and cholecystitis. Biloma was confirmed by sono-guided percutaneous needle aspiration and was drained through a pigtail catheter. After the successful treatment by percutaneous drainage and endoscopic sphincterotomy, the patient recovered. Here, we report an uncommon case of spontaneous biloma formation in association with choledocholithiasis with a review of literatures.  相似文献   
48.
巨噬细胞迁移抑制因子最初是由于能抑制体外巨噬细胞随机迁移而被发现,现在它作为一种重要的调节因子参与一系列炎症性疾病过程.我们最近发现,巨噬细胞迁移抑制因子的缺失使一些由炎症介质诱发的白细胞-内皮细胞相互作用减弱,提示巨噬细胞迁移抑制因子在炎症反应中起作用的机制之一是促进白细胞聚集.……  相似文献   
49.

Background

Understanding the relationship between alcohol abuse, a common and theoretically modifiable condition, and the most common cause of death in the world, cardiovascular disease, may inform potential prevention strategies.

Objectives

The study sought to investigate the associations among alcohol abuse and atrial fibrillation (AF), myocardial infarction (MI), and congestive heart failure (CHF).

Methods

Using the Healthcare Cost and Utilization Project database, we performed a longitudinal analysis of California residents ≥21 years of age who received ambulatory surgery, emergency, or inpatient medical care in California between 2005 and 2009. We determined the risk of an alcohol abuse diagnosis on incident AF, MI, and CHF. Patient characteristics modifying the associations and population-attributable risks were determined.

Results

Among 14,727,591 patients, 268,084 (1.8%) had alcohol abuse. After multivariable adjustment, alcohol abuse was associated with an increased risk of incident AF (hazard ratio [HR]: 2.14; 95% confidence interval [CI]: 2.08 to 2.19; p < 0.0001), MI (HR: 1.45; 95% CI: 1.40 to 1.51; p < 0.0001), and CHF (HR: 2.34; 95% CI: 2.29 to 2.39; p < 0.0001). In interaction analyses, individuals without conventional risk factors for cardiovascular disease exhibited a disproportionately enhanced risk of each outcome. The population-attributable risk of alcohol abuse on each outcome was of similar magnitude to other well-recognized modifiable risk factors.

Conclusions

Alcohol abuse increased the risk of AF, MI, and CHF to a similar degree as other well-established risk factors. Those without traditional cardiovascular risk factors are disproportionately prone to these cardiac diseases in the setting of alcohol abuse. Thus, efforts to mitigate alcohol abuse might result in meaningful reductions of cardiovascular disease.  相似文献   
50.
Phosphorylation of factor Va and factor VIIIa by activated platelets   总被引:3,自引:3,他引:3  
Kalafatis  M; Rand  MD; Jenny  RJ; Ehrlich  YH; Mann  KG 《Blood》1993,81(3):704-719
Platelet activation leads to the incorporation of 32[PO4(2-)] into bovine coagulation factor Va and recombinant human factor VIII. In the presence of the soluble fraction from thrombin-activated platelets and (gamma-32P) adenosine triphosphate, radioactivity is incorporated exclusively into the M(r) = 94,000 heavy chain (H94) of factor Va and into the M(r) = 210,000 to 90,000 heavy chains as well into the M(r) = 80,000 light chain of factor VIII. Proteolysis of the purified phosphorylated M(r) = 94,000 factor Va heavy chain by activated protein C (APC) gave products of M(r) = 70,000, 24,000, and 20,000. Only the intermediate M(r) = 24,000 fragment contained radioactivity. Because the difference between the M(r) = 24,000 and M(r) = 20,000 fragments is located on the COOH-terminal end of the bovine heavy chain, phosphorylation of H94 must occur within the M(r) = 4,000 peptide derived from the carboxyl-terminal end of H94 (residues 663 through 713). Exposure of the radioactive factor VIII molecule to thrombin ultimately resulted in a nonradioactive light chain and an M(r) = 24,000 radioactive fragment that corresponds to the carboxyl-terminal segment of the A1 domain of factor VIII. Based on the known sequence of human factor VIII, phosphorylation of factor VIII by the platelet kinase probably occurs within the acidic regions 337 through 372 and 1649 through 1689 of the procofactor. These acidic regions are highly homologous to sequences known to be phosphorylated by casein kinase II. Results obtained using purified casein kinase II gave a maximum observed stoichiometry of 0.6 mol of 32[PO4(2-)]/mol of factor Va heavy chain and 0.35 mol of 32[PO4(2-)]/mol of factor VIII. Phosphoamino acid analysis of phosphorylated factor Va by casein kinase II or by the platelet kinase showed only the presence of phosphoserine while phosphoamino acid analysis of phosphorylated factor VIII by casein kinase II showed the presence of phosphothreonine as well as small amounts of phosphoserine. The platelet kinase responsible for the phosphorylation of the two cofactors was found to be inhibited by several synthetic protein kinase inhibitors. Finally, partially phosphorylated factor Va was found to be more sensitive to APC inactivation than its native counterpart. Our findings suggest that phosphorylation of factors Va and VIIIa by a platelet casein kinase II- like kinase may downregulate the activity of the two cofactors.  相似文献   
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