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51.
老年脑梗死患者急性期血小板活化功能定量检测   总被引:11,自引:2,他引:9  
目的 :探讨老年脑梗死患者外周血中血小板膜糖蛋白变化的临床意义。 方法 :应用流式细胞术检测了 6 8例急性期老年脑梗死患者外周血血小板活化分子标记物CD4 1、CD6 2p和CD6 3的含量水平 ,与 4 2例正常老年人对照 ;并对脑梗死组病灶大小、梗死部位、病情分级等与血小板活化分子表达的变化进行分析 ,应用统计学进行处理。 结果 :急性期脑梗死患者血小板粘附分子CD4 1、CD6 2 p和CD6 3的表达水平显著高于正常对照组 (P <0 .0 1) ,且与梗死灶大小及病情分级密切相关 ,与梗死部位无关。 结论 :老年脑梗死患者急性期外周血血小板活化功能明显增强 ,为早期应用抗血小板聚集药物的治疗提供了实验依据  相似文献   
52.
We developed a semiautomatic method termed “cortical circumferential profiling” for objective analysis of cerebral cortex function in emission tomographic neuroimaging studies. This method treats cortex as a continuous ring near the outer brain edge. A computer algorithm samples the cortex at 60 contiguous, equiangular locations, using 1-cm2 samples. These values are plotted as a function of cortical angle to produce the cortical circumferential profile. This method was used in a study of regional cerebral perfusion in 15 patients with Alzheimer's disease and 8 elderly control subjects using N-isopropyl [I-123]-iodoamphetamine. Cortical circumferential profiling decreases variability, examines the entire cortex within slices at preselected levels above the orbital-meatal line, and facilitates intrasubject and intersubject comparisons.  相似文献   
53.
Microvascular thrombosis is a prominent feature in cardiac delayed xenograft rejection (DXR). We investigated the impact of warfarin or low-molecular-weight heparin (LMWH) anti-coagulation on xenograft function using a heterotopic pig-to-primate model. Donor hearts were from CD46 transgenic pigs and baboon immunosuppression included tacrolimus, sirolimus, anti-CD20 and TPC, an alpha-galactosyl-polyethylene glycol conjugate. Three groups of animals were studied. Group 1 (n = 9) was treated with warfarin, Group 2 (n = 13) with LMWH and Group 3, received no anti-coagulant drugs. The median duration of xenograft function was 20 days (range 3-62 days), 18 days (range 5-109 days) and 15 days (range 4-53 days) in Groups 1 to 3 respectively. Anti-coagulation achieved the targeted international normalized prothrombin ratio (INR) and anti-factor Xa levels consistent with effective in vivo therapy yet, no significant impact on median xenograft function was observed. At rejection, a similar histology of thrombosis and ischemia was apparent in each group and the levels of fibrin deposition and platelet thrombi in rejected tissue was the same. Anti-coagulation with warfarin or LMWH did not have a significant impact on the onset of DXR and microvascular thrombosis. However, a role for specific anti-coagulant strategies to achieve long-term xenograft function cannot be excluded.  相似文献   
54.
经颅彩色双功超声是一种新型、无创的超声诊断仪,高空间分辨率显示颅内血管和脑实质的结构,笔者查阅了近年来相关文献,主要综述经颅彩色多普勒血流显像在颅脑血管疾病中的诊断价值,同时讨论二维经颅超声的应用及新的实验性显像技术。  相似文献   
55.
Lesion evolution during focal cerebral ischemia may depend on flow restrictions or on accumulation of toxic mediators within the infarct and expansion of these factors to the periinfarct region. So far, the precise contribution of flow dependent versus spreading-mediated impairment of viable periinfarct tissue has not been determined. Therefore, we measured lesion expansion, flow restrictions and glutamate distribution on serial brain sections at different time points after experimental focal ischemia.Permanent focal ischemia was induced by occlusion of the right middle cerebral artery in male rats and the flow reduction was subsequently measured at 1, 12 and 24 h using iodo[14C]antipyrine autoradiography. Additionally, the necrotic volume was determined on serial brain sections and the glutamate content was measured in tissue samples from adjacent microdissections.Twelve hours after focal ischemia no noteworthy viable areas with blood flow restrictions of 20-40 ml 100 g− 1 min− 1 existed but at 24 h the necrotic tissue exceeded the hemodynamically compromised region by 40 ± 21 mm3 (24%). Furthermore, at 12 and 24 h the glutamate content was elevated in areas surrounding the infarct.Relevant flow restrictions are detectable only during early stages of infarct maturation, whereas the propagation of secondary factors may be the predominant mechanism for delayed infarct evolution.  相似文献   
56.
血浆同型半胱氨酸水平与动脉粥样硬化和脑梗死的关系   总被引:1,自引:1,他引:0  
目的 探讨血浆同型半胱氨酸(Hcy)水平与颈动脉粥样硬化和脑梗死关系.方法 2005-05~2006-02收治的91例脑梗死住院患者被列入研究对象.根据病灶大小分3组大片梗死21例,小片梗死44例,腔隙性梗死26例.根据颈动脉彩超检测结果将研究对象分为颈动脉斑块组34例,无颈动脉斑块组57例.全部患者测定血浆Hcy、血清叶酸、VitB12水平.分析血浆Hcy水平与脑梗死的危险因素、病灶大小、颈动脉粥样硬化斑块及血清叶酸、VitB12的关系.结果 血浆Hcy水平(1)与高血压、糖尿病、血脂、性别、年龄各指标无明显相关关系.(2)与脑梗死病灶大小无关.(3)与颈动脉粥样硬化斑块有关,有斑块34例,血浆Hcy(20.73±9.31)μmol/L,无斑块57例,血浆Hcy (15.46±11.4) μmol/L,前者高于后者(P<0.05).(4)与血清叶酸、VitB12水平呈负相关(r1s=-0.264,r2s=-0.16,P<0.05).结论 血浆Hcy水平与脑梗死病灶大小无关;Hcy水平升高与颈动脉粥样硬化斑块密切相关;与血清叶酸、VitB12水平呈负相关.高血浆Hcy血症可能是颈动脉粥样硬化的危险因素,但与脑梗死关系不明确.  相似文献   
57.
目的了解窒息新生儿在听觉刺激诱发脑神经活动时的脑氧合代谢和脑血流量的改变。 方法1998~2003年北京中日友好医院儿科选择窒息新生儿34例为窒息组,健康新生儿40名为对照组。使用近红外光谱仪,观察听觉刺激试验诱发的脑氧合血红蛋白\[Hb O2\]、还原血红蛋白\[Hb H\]和总血红蛋白\[Hb tot\]浓度的变化,并比较两组脑氧合代谢和脑血流量的改变。根据\[Hb O2\]、\[Hb H\]和\[Hb tot\]不同的变化,将氧合代谢曲线分为A(\[Hb O2\]、\[Hb H\]和\[Hb tot\]均增加); B(\[Hb O2\]和\[Hb tot\]增加,\[Hb H\]降低);C(\[Hb O2\]和\[Hb tot\]降低,\[Hb H\]增加)3种曲线类型。 结果窒息组中25例(25/34、73.5%)显示C型变化,对照组中28例(28/40、70.0%)显示A型变化,两组中A、C两型例数比较差异显著(P<0.05)。两组\[Hb O2\]和\[Hb tot\]数值变化幅度比较差异显著(P<0.05)。 结论窒息新生儿听觉刺激诱发相应皮层的神经活动时,显示局部脑血流量下降、氧合代谢降低,重度窒息儿更明显。  相似文献   
58.
We present a case report of a patient suffering from portal and superior mesenteric vein thrombosis secondary to splenectomy. No surgical procedure could be performed due to the extension of thrombus.Local fibrinolysis treatment with urokinase through a percutaneous transhepatic approach was decided upon, and this procedure had a successful patient outcome.  相似文献   
59.
目的探讨NO合成底物左旋-精氨酸(L-Arg)对兔局灶脑缺血后血管再生和脑细胞凋亡的影响。方法兔局灶脑缺血后应用L-Arg,流式细胞仪定量分析细胞凋亡率的变化,CD34免疫组织化学测脑组织微血管密度(MVD),脑组织含水率评价脑水肿。结果与对照组比较,L-Arg组脑细胞凋亡率明显减少(8.72±2.62 vs 16.62±2.82,P<0.01),同时脑组织MVD却明显增加(1.21±0.43 vs 0.69±0.22,P<0.01)。结论外源性L-Arg可减少缺血后脑细胞凋亡并促进缺血后血管再生,对局灶脑缺血具有重要的神经保护作用。  相似文献   
60.
BACKGROUND/OBJECTIVE: The efficacy of a direct factor (F)Xa inhibitor, ZK-807834, was compared with indirect inhibition by enoxaparin for inhibition and deaggregation of acute platelet-rich thrombi in a well-characterized porcine carotid injury model. METHODS: A crush injury was performed on a randomly chosen carotid artery and the thrombus allowed to propagate for 30 min. Pigs then received intravenous drug for 35 min: ZK-807834-Dose 1 (40 microg kg(-1) bolus + 1.5 microg kg(-1) min(-1) infusion, n=6); ZK-807834-Dose 2 (20 microg kg(-1) bolus + 0.75 microg kg(-1) min(-1) infusion; n=6); enoxaparin (1 mg kg(-1) bolus; n=6); or saline (n=6). Five minutes after drug initiation, the contralateral artery was injured. Thrombus size was monitored by scintillation detection of autologous 111In-platelets. RESULTS: The prothrombin time ratio was 2.2 +/- 0.1; 1.4 +/- 0.3; 1.2 +/- 0.9 and 1.1 +/- 0.2, respectively. ZK-807834-Dose 1 significantly inhibited carotid platelet deposition (525 +/- 226 x 10(6) cm(-2); P = 0.008), whereas ZK-807834-Dose 2 (2325 +/- 768) and enoxaparin (1236 +/- 383) were not different from saline (2776 +/- 642). Thrombus deaggregation was greatest for animals receiving ZK-807834-Dose 1 (473 +/- 185). Neither ZK-807834-Dose 2 (1588 +/- 480) nor enoxaparin (1618 +/- 686) was different from saline control (2222 +/- 598). CONCLUSIONS: Direct FXa inhibition with ZK-807834, at a prothrombin time ratio of 2.2, effectively inhibits thrombosis and promptly deaggregates thrombi induced by arterial injury. In contrast, indirect FXa inhibition with enoxaparin was ineffective.  相似文献   
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