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991.
Prolonged dilatation with an autoperfusion balloon catheter (APBC) (High-Flow-CPC-Mainz (Schneider) in 23 cases and Stack Perfusion (ACS) in 50 cases) was carried out in 73 patients (60 men, 13 women, mean age 59.3 +/- 8.8 years) with acute vascular complications occurring during PTCA (25 occlusive dissections (34%), five thrombotic occlusions (7%), 42 non-occlusive dissections (58%) and one non-occlusive thrombus with reduction of flow (1%)) in order to avoid stent implantation or emergency bypass surgery. On average 1.5 +/- 0.8 inflations were carried out per patient with a mean maximum inflation time of 14.1 +/- 8.4 min and a mean total inflation time of 16.8 +/- 12.3 min. In 61 patients (83.5%), the vascular complication could be controlled successfully with APBC, but in 12 APBC was not successful. Eight patients (11%) had emergency surgery. A stent was implanted in three patients (4.1%), and one suffered an acute myocardial infarction. Out of the 61 patients with positive result after prolonged dilatation, the hospital phase was uncomplicated in 53 (86.9%), five (8.2%) suffered an infarct with a maximum rise in CK of 350 U.l-1, two with multivessel disease had elective operations and one was dilated a second time because of a subacute reocclusion. Our experience indicates that when an acute vascular complication occurs, prolonged dilatation with an APBC is good interventional therapy avoiding stent implantation or emergency bypass surgery. However, new techniques cannot always replace surgery so an emergency bypass operation may still be necessary.  相似文献   
992.
关木通致急性肾小管坏死患者肾间质微血管病变的研究   总被引:10,自引:0,他引:10  
Yang L  Li XM  Wang SX  Wang HY 《中华内科杂志》2005,44(7):525-529
目的探讨肾间质微血管病变在关木通致急性肾小管坏死肾间质纤维化中的作用及发生机制。方法取4例关木通致急性肾小管坏死患者(A组)、5例抗生素致急性肾小管坏死患者(B组)、5例非IgA型轻度系膜增生性肾小球肾炎患者(C组)肾活检标本,免疫组化SP法观察肾小管上皮血管内皮生长因子(VEGF)表达及肾小管周围毛细血管(PTC)密度及形态改变,电镜观察微血管内皮细胞和基底膜的结构变化。结果(1)A组PTC数目明显少于B组及C组(P<0.01),并可见管腔扩张变形或缩小、血管壁断裂。(2)A组电镜见PTC内皮细胞肿胀,有胞质空泡、致密颗粒,细胞局部与基底膜分离。基底膜有皱缩及增厚。(3)A组肾小管上皮VEGF表达明显少于B组,但2组VEGF表达均多于C组。(4)A、B组PTC密度与肾小管VEGF表达呈正相关(均r=0.793,P<0.01),与肾小管上皮再生呈正相关(r分别为0.880、0.802,P值均小于0.01)。结论关木通致急性肾小管坏死存在原发性肾间质微血管损伤,肾小管VEGF低表达可能参与了损伤过程。关木通致急性肾小管坏死中的微血管病变可能是肾小管中毒性损伤后修复不良及病变慢性化进展的原因之一。  相似文献   
993.
BackgroundCarotid and femoral plaque burden is a recognized biomarker of cardiovascular disease risk. A new electronic-sweep 3-dimensional (3D)–matrix transducer method can improve the functionality and image quality of vascular ultrasound atherosclerosis imaging.ObjectivesThis study aimed to validate this method for plaque volume measurement in early and intermediate–advanced plaques in the carotid and femoral territories.MethodsPlaque volumes were measured ex vivo in pig carotid and femoral artery specimens by 3-dimensional vascular ultrasound (3DVUS) using a 3D-matrix (electronic-sweep) transducer and its associated 3D plaque quantification software, and were compared with gold-standard histology. To test the clinical feasibility and accuracy of the 3D-matrix transducer, an experiment was conducted in intermediate–high risk individuals with carotid and femoral atherosclerosis. The results were compared with those obtained using the previously validated mechanical-sweep 3D transducer and established 2-dimensional (2D)–based plaque quantification software.ResultsIn the ex vivo study, the authors assessed 19 atherosclerotic plaques (plaque volume, 0.76 µL-56.30 μL), finding strong agreement between measurements with the 3D-matrix transducer and the histological gold-standard (intraclass correlation coefficient [ICC]: 0.992; [95% CI: 0.978-0.997]). In the clinical analysis of 20 patients (mean age 74.6 ± 4.45 years; 40% men), the authors found 64 (36 carotid and 28 femoral) of 80 scanned territories with atherosclerosis (measured atherosclerotic volume, 10 μL-859 μL). There was strong agreement between measurements made from electronic-sweep and mechanical-sweep 3DVUS transducers (ICC: 0.997 [95% CI: 0.995-0.998]). Agreement was also high between plaque volumes estimated by the 2D and 3D plaque quantification software applications (ICC: 0.999 [95% CI: 0.998-0.999]). Analysis time was significantly shorter with the 3D plaque quantification software than with the 2D multislice approach with a mean time reduction of 46%.Conclusions3DVUS using new matrix transducer technology, together with improved 3D plaque quantification software, simplifies the accurate volume measurement of early (small) and intermediate–advanced plaques located in carotid and femoral arteries.  相似文献   
994.
目的 探讨 80岁以上高龄患者的周围血管疾病外科治疗的可行性。方法 对 30例 80岁以上高龄的急、慢性周围动脉闭塞患者的血管外科治疗进行回顾性分析。结果  30例患者共施周围血管手术 32例次 ,术后 30d内病死率为 16 .7% (5 30 ) ,肢体保全率为 71.9% (2 3 32 )。其中急诊死亡为 2 7.3% (3 11) ,择期死亡为 10 .5 3% (2 19)。随访 2 4个月 ,全组生存率为 76 .7% (2 3 30 ) ,肢体保全率为 6 5 .6 % (2 1 32 )。结论 对经选择的 80岁以上患者施行周围血管手术是可行的 ,术后死亡率低 ,远期效果良好。  相似文献   
995.
Angiogenesis is a crucial process in the progression of multiple myeloma (MM). Vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) are multifunctional cytokines that potently stimulate angiogenesis including tumour neovascularization. Serum levels of VEGF and HGF were measured in 52 patients with MM by enzyme-linked immunosorbent assay (ELISA). Serum levels of VEGF and HGF were elevated in MM patients compared with healthy controls (VEGF: mean 0.31 ng/ml and 0.08 ng/ml respectively, P < 0.01; HGF: mean 2.17 ng/ml and 0.45 ng/ml, respectively, P < 0.001). In serial samples taken after chemotherapy, serum VEGF and HGF levels were correlated with M-protein levels. Serum levels of VEGF were higher in patients with extramedullary plasmacytomas than in patients without them (P < 0.05). They were also significantly higher in a group of patients who showed poor response to chemotherapy (P < 0.01). Serum levels of HGF were higher in patients with complications such as anaemia, hypercalcaemia and amyloidosis than in patients without these complications (P < 0.01, P < 0.05, P < 0.05 respectively). Both serum VEGF and HGF levels were significant predictors of mortality (P = 0.01, P = 0.02, respectively, log-rank test). The present study demonstrated that serum levels of VEGF and HGF are significantly elevated and dependent on the severity of MM, suggesting that measurement of VEGF and HGF may be useful for assessing disease progression and for predicting the response to chemotherapy in MM patients.  相似文献   
996.

Background

Withdrawal of chronic beta-blockade following vascular surgery is associated with peri-operative mortality. The aim of this study was to examine risk factors associated with mortality in patients where chronic beta-blockade was withdrawn.

Methods

Two matched case–control studies were conducted, one of patients withdrawn from beta-blockade who survived and the other of patients who were maintained on beta-blockade and survived. Each case was matched with two controls. Three potential risk factors were analysed: the increase in heart rate postoperatively, the use of inotropes, and whether withdrawal for the first three postoperative days was more predictive than withdrawal for a single day. Multivariate conditional logistic regression was conducted.

Results

The only independent predictor of in-hospital mortality was a change in the mean daily heart rate of ≥ six beats per minute from the day of surgery to the third postoperative day, or death or discharge if this happened before the third day (OR 13.7, 95% CI: 1.7–110, p = 0.014). The area under the curve for the receiver operating characteristic curve was 0.787.

Conclusion

Use of a postoperative heart rate threshold may be clinically useful as an ‘early warning system’ in patients withdrawn from chronic beta-blockade in the peri-operative period.  相似文献   
997.
目的探讨CD34和血管内皮生长因子(VEGF)在肝细胞肝癌(HCC)组织中的表达及微血管密度(MVD)的临床病理意义。方法应用链霉素扰生物素蛋白-过氧化物酶法(S—P法)对50例HCC患者进行肿瘤血管生成免疫组织化学检测。对CD34阳性血管进行MVD计数.对VEGF进行半定量计数,并分析与HCC的临床病理特征的关系及意义。结果CD34在HCC组织中呈广泛、窦隙状表达,MVD值在有汇管区癌栓和肝内转移者高于无汇管区癌栓和无肝内转移者(P〈0.05),VEGF表达的阳性率在有汇管区癌栓和肝内转移者明显高于元汇管区癌栓及无肝内转移者(P〈0.05)。MVD值在VEGF阳性组和阴性组之间差异有显著性(P〈0.05)。结论HCC中MVD值和VEGF阳性表达率明显增高,由自分泌和旁分泌产生的VEGF通过促进HCC肿瘤血管生成而促进HCC的生长和转移。  相似文献   
998.
999.
AIMS: Conventional and genetic risk factors have been reported to play a role in the pathogenesis of vascular disease, but do not explain the lower burden of cardiac and peripheral vascular disease (PVD) in Chinese compared with Caucasians. The role of renin-angiotensin system (RAS) gene polymorphisms and conventional vascular risk factors has not been determined. METHODS: A total of 3097 Chinese diabetic subjects were screened for PVD, which was identified in 194 of the 2967 patients with Type 2 diabetes. Biochemical parameters and the genotype and allele frequencies of three RAS gene polymorphisms, the angiotensin-converting enzyme (ACE) insertion/deletion, angiotensinogen (AGT) M235T and angiotensin II type 1 receptor (AT1R) A1166C polymorphisms were then compared between the PVD patients and 1046 age, gender and diabetes duration-matched patients without PVD. RESULTS: PVD identified in 6.5% was associated with significantly worse glycaemic control, lipid profile and renal function. Smoking was more common, as were the other macro- and microvascular diseases. The prevalence of hypertension was similar between the groups, yet diastolic blood pressure was slightly lower in the PVD group. The ACE D allele was significantly more frequent in patients with PVD compared with the matched diabetic controls (38.1 vs. 29.8%, P = 0.039). No differences in the AT1R or AGT polymorphisms were observed. CONCLUSIONS: PVD was associated with a worse metabolic profile and greater concomitant vascular disease than controls. The ACE I/D polymorphism was associated with PVD in these Type 2 diabetic patients.  相似文献   
1000.
More than 70% of percutaneous coronary interventions are followed by a stent implantation. In-stent restenosis still occurs in 20-30% of patients and remains a therapeutic challenge. At present only vascular brachytherapy has been shown to be an effective treatment option. We report here one case of recurrent in-stent restenosis after vascular brachytherapy that was successfully treated by a second beta radiation treatment.  相似文献   
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