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31.
目的:分析血脂代谢异常与冠状动脉狭窄程度的关系.方法:对366例因胸痛而就诊的患者行选择性冠状动脉造影,按冠状动脉狭窄程度分为正常对照组、单支病变组、双支病变组、多支病变组.同时观察患者血脂各成分,并对各组指标进行统计学分析.结果:总胆固醇(TC)、甘油三脂(TG)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C),在各组之间存在差异,尤其多支病变组与正常组之间差异显著(P<0.01).TC、TG、LDL-C随冠状动脉病变加重而增加,HDL-C随冠状动脉病变加重而减少,LDL-C与冠状动脉狭窄程度呈正相关,HDL-C与冠状动脉狭窄程度呈负相关.结论:血脂代谢紊乱与冠状动脉狭窄的发生发展有内在的联系,对于预测有无冠状动脉病变及其进展有一定临床意义.  相似文献   
32.
OBJECTIVE: To examine the effect of short-term improvements in glycaemic control on brachial artery endothelial function as a marker of cardiovascular health. METHODS: Persons with Type 2 diabetes who were poorly controlled on oral therapy were randomly assigned to monotherapy with repaglinide or combination therapy with repaglinide plus metformin. Brachial artery flow-mediated vasodilation was assessed by ultrasonography at randomization and following 16 weeks of therapy. The primary outcome was change in brachial artery endothelial function from baseline. Comparison of randomized groups was a secondary aim. RESULTS: Eighty-six participants were randomized, and 83 were followed to study completion. Post occlusion brachial artery vasodilation was 3.74% at baseline and 3.82% following 16 weeks of therapy (P = 0.77). The treatment effect was 0.08% (95% CI: -0.48%, 0.64%). No difference was seen between treatment groups (P = 0.69). Overall, A1C was reduced from 8.3% to 7.0%, with a greater reduction in the combination therapy group (from 8.4% to 6.7%) than in the monotherapy group (from 8.3% to 7.3%, p for difference between groups = 0.01). Statistically significant reductions were observed in fasting glucose, and plasminogen activator inhibitor-1. Statistically significant increases were observed for fasting insulin, uric acid, weight and BMI. CONCLUSIONS: Brachial artery endothelial function was not influenced by short-term improvements in glycaemic control. The CONTROL DM group was successful in lowering A1C. Future research should explore more intensive and longer-lasting improvements in glycaemic control on endothelial function. Some data previously published in abstract form (Diabetes 2001; 50 (Suppl. 2): A217).  相似文献   
33.
Summary We observed a rare cerebrovascular anomaly in a patient with brain-stem infarction. Two right vertebral arteries arose from the subclavian artery and communicated directly with each other under the transverse foramen of the fourth cervical vertebra. The left vertebral artery consisted of a rudimentary artery that arose from the left subclavian artery, ran through the transverse foramen of the sixth cervical vertebra and then tapered down to disappear at the fourth/fifth cervical vertebrae, plus a second, accessory artery that arose from a branch of the left thyrocervical trunk, ran through the transverse foramen of the fifth cervical vertebra and tapered off to disappear at the first/second cervical vertebrae.  相似文献   
34.
Summary A patient with symptomatic bilateral aberrant cervical internal carotid arteries, demonstrated on CT and MRI, is described.  相似文献   
35.
We describe a patient with two separate vessels having different origins supplying the circumflex coronary artery distribution. This represents a previously undescribed coronary artery anomaly.  相似文献   
36.
目的:建立大鼠颈动脉再狭窄模型,原位灌注固定取材。评价PTA后血管重塑(VR)的动态变化规律,定量分析血管重塑在血管再狭窄过程中的变化及作用。方法:制作70只SD雄性大鼠颈总动脉再狭窄模型,分原位灌注实验组、对照组,于术后1h、3、7、14、28和42天原位灌注固定取材,行HE染色、Masson染色,观察标本血管狭窄情况。结果:①血管重塑指数(VRI)在PTA后即刻最大,3天组明显降低,7天组稍有增大,其后不断减小,剩余血管腔面积百分比同VRI的变化曲线基本一致。②FFA后,血管腔面积总体呈逐渐缩小趋势,内弹力板围绕面积(IELA)1h组较对照组明显增大,3天组较1h组明显缩小,14、28、42天组较对照组明显缩小。外弹力板围绕面积(EELA)逐渐缩小。EELA、IELA的变化与血管腔面积变化呈正相关。③VRI与血管腔面积的变化呈正相关,新生内膜面积与剩余狭窄率、血管腔面积无直线相关。结论:再狭窄过程中存在扩张性重塑和收缩性重塑现象,管腔的狭窄与否取决于血管重塑指数的变化,而不是新生内膜的变化,新生内膜的形成是血管重塑过程中的一部分。IELA和EELA可作为判断管腔狭窄及评价血管重塑的指标。  相似文献   
37.
OBJECTIVE: To assess the accuracy of three-dimensional color Doppler sonography and uterine artery arteriography in depicting changes in fibroid vascularity before and after embolization. METHODS: Preembolization and postembolization three-dimensional color Doppler sonography and selective uterine artery arteriography were retrospectively compared in 15 patients who underwent uterine artery embolization for treatment of symptomatic fibroids. Three-dimensional color Doppler sonography was performed by using a scanner with color power angiographic imaging capability. Vascularity was quantified by using an estimation of power-weighted pixel density as described by our group in previously published studies. Uterine artery arteriography was performed by using a standard selective microcatheter embolization technique. For purposes of comparison, fibroids were classified as either hypervascular or hypovascular relative to myometrial vascularity before and minutes to several hours after uterine artery embolization. Changes in fibroid vascularity (i.e., from hypervascular to hypovascular) as depicted by three-dimensional color Doppler sonography were compared with those shown on uterine artery arteriography and classified as being in agreement or disagreement. RESULTS: In 13 (87%) of 15 patients there was agreement; in 2 (13%) of 15 there was disagreement. In both cases of disagreement, three-dimensional color Doppler sonography showed collateral flow not depicted by uterine artery arteriography The mean reduction in quantitated vascularity after uterine artery embolization was 44% (range, 19%-78%). CONCLUSIONS: Three-dimensional color Doppler sonography accurately depicts fibroid vascularity and in some cases can reveal collateral flow not depicted by uterine artery arteriography.  相似文献   
38.
Summary The monocrofaline-induced structural changes of small pulmonary arteries in rat and their relationship with pulmonary hypertension and right ventricular hypertrophy were observed by determining the right ventricular systolic pressure, and by light and electron microscope and morphometry. One to 38 days after last injection of monocrotaline (MCT), a medial thickening and lumen marrrowing of the circular muscular arteries (CMA), accompanying terminal (TB) and respiratory bronchioles (RB), were found. And there after the lumen of CMA, accompanying TB, became dilated, and its medial thickness (MT) decreased, whereas the histopathologic changes of the partially muscular arteries (PMA), accompanying RB, became severe, their MT increased continuously, and finally reached the peak value on Day 50. At the first day after last MCT treatment, inflammation and muscularization were found in PMA and nonmuscular arteries (NMA), and became more severe with the cause of disease. Therefore, the intra-acinar pulmonary arteries, both CMA and PMA, increased in number while the NMA decreased in number significantly because of the structural remodeling. Four days after MCT treatment, the right ventricular systolic pressure began to rise, and reached its peak value on Day 50. Eight days after MCT injection, right ventricular hypertrophy developed, and became most significant from Day 23 to Day 30. The results suggest that structural remodeling, i.e. muscularization, of intra-acinar pulmonary arteries plays an important role in the development of pulmonary hypertension and right ventricular hypertrophy.  相似文献   
39.
Haemodynamic studies in early stroke   总被引:2,自引:0,他引:2  
Summary We investigated prospectively a consecutive series of 81 patients suffering from acute middle cerebral artery (MCA) ischaemia by transcranial Doppler ultrasonography (TCD) within 24 h of the onset of symptoms. To monitor the haemodynamic changes follow-up recordings were carried out at short intervals during the next 2–3 weeks until stable haemodynamic status was achieved. In order to estimate the value of early TCD examinations in predicting the extent of brain damage seen later on, initial MCA flow reduction was correlated with infarction size and pattern on computed tomography. Fifty-three cases showed sufficient ultrasound penetration through the temporal bone. MCA flow asymmetries were recorded in 45 patients (85%); occlusion was observed in 17. Recanalization occurred in 11 patients followed by transient hyperaemia in 3, leaving residual stenosis in 2. Initial increase of flow velocities normalized within days or weeks in 7 out of 9 patients, while 2 developed residual MCA stenosis. Nineteen patients showed a considerable flow reduction on admission, which returned to normal in 9; transient hyperaemia was detected in 5 of these. Eight patients did not show any MCA flow asymmetry. Our study revealed very variable haemodynamic changes in acute stroke, which influenced further diagnostic and therapeutic management. The high rate of spontaneous recanalizations of MCA occlusions followed by transient hyperaemia in many cases has an important bearing on thrombolytic or theological therapy. Flow velocity differences could be related to infarction pattern rather than to infarction volume. Early MCA flow asymmetry recorded by TCD within the first 24 h could not reliably predict the extent of persistent brain damage or clinical outcome.  相似文献   
40.
目的 研究支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌 (NSCLC)的可行性及临床价值。方法  76例NSCLC患者随机分成A、B 2组 ,A组先行 2次支气管动脉灌注化疗 (BAI) ,第 2次BAI 1~ 2周后再行直线加速器放射治疗 (RT) ;B组单纯行 2次BAI (对照组 )。结果 临床疗效 ,A组 (BAI RT)和B组 (BAI)分别为 89.47%和 60 .5 3% (Ρ <0 .0 1) ;1、3年生存率 ,A、B组分别为 81.5 8%、5 0 .0 0 %和 60 .5 3%、2 1.0 5 % ( 0 .0 1<Ρ <0 .0 5 )。结论 支气管动脉灌注化疗联合直线加速器放射治疗Ⅲa期非小细胞肺癌的临床疗效和患者 1、3年生存率均显著提高  相似文献   
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