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71.
作者选择乙基纤维素、聚乙烯醇等高分子材料制成涂膜剂,用大鼠皮进行双氯灭痛药膜的体外透皮速率测定。结果表明,氮酮与丙二醇可以促进药物渗透。不同的高分子材料可影响药物的扩散与释放,从而影响其透皮速率。与无膜无促透剂处方相比,药物在乙基纤维素中的透皮速率没有增加,在聚乙烯醇膜中的透皮速率有显著增加。 相似文献
72.
Kazushi Tsuda Keizo Kimura Hiroki Shima Ichiro Nishio Yoshiaki Masuyama 《Clinical and experimental pharmacology & physiology》1992,19(7):531-535
The present study was designed to investigate the presynaptic alpha 2-adrenoceptor function to inhibit norepinephrine (NE) release in blood vessels of reduced renal mass salt hypertensive rats (Na-loaded HT). Isolated perfused mesenteric vasculatures were prepared from Na-loaded HT and normotensive control rats (NT-control), and the NE release and vascular responsiveness were examined. Periarterial nerve stimulation caused a significantly greater release of NE and pressor responses in Na-loaded HT than in NT-control. Yohimbine, a potent alpha 2-adrenoceptor antagonist, demonstrated the facilitatory effects on NE release during nerve stimulation. The effects were significantly attenuated in Na-loaded HT compared with NT-control. These results demonstrate that vascular sympathetic nervous activity might be enhanced in Na-loaded HT. Furthermore, the increased NE release from vascular adrenergic neurons in Na-loaded HT could partially depend on impaired presynaptic alpha 2-adrenoceptor-mediated modulation, which might contribute to the pathogenesis and maintenance of this form of salt-dependent hypertension. 相似文献
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74.
IgA肾病大鼠血清IgA-纤维连接蛋白的检测及意义 总被引:2,自引:0,他引:2
目的 检测IgA肾病大鼠血清IgA-纤维连接蛋白水平,探讨其在IgA肾小球系膜沉积中的作用。方法 肝叶切除后,尾静脉注射脂多糖,制作IgA肾病大鼠模型。应用ELISA法检测血清IgA-纤维连接蛋白聚合物水平,半定量法对系膜IgA免疫荧光强度评分,二者作相关性分析。结果 IgA肾病时,血清IgA-纤维连接蛋白聚合物水平升高,并与系膜IgA沉积呈正相关。结论 IgA肾病时,血清IgA-纤维连接蛋白聚合物水平是升高的,且可能是导致IgA系膜沉积的原因之一。 相似文献
75.
2-chloroprocaine antagonism of epidural morphine analgesia 总被引:2,自引:0,他引:2
Background: 2-chloroprocaine (2-CP) used for lumbar epidural anesthesia (LEA) reportedly decreases the efficacy of epidural morphine (EM) administered for post-cesarean section (CS) analgesia. The amount of supplemental i.v. morphine self-administered by the patient via the patient-controlled analgesia device (PCA) is used to study the interaction between EM and 2-CP.
Methods: Forty-two patients scheduled for elective CS were randomly divided into 3 equal groups, and received 2-CP, 2-CP+epinephrine (Epi, 5 μg ml-1 ) or 2% lidocaine (Lido) with Epi for LEA. All patients received 5 mg EM and i.v. PCA morphine for postoperative pain. Cumulative amount of i.v. morphine used in the first 24 hours as well as the amount of the drug used during each 2-h period were noted. Nonparametric analysis of variance and Chi-squared analysis were used for statistical comparisons.
Results: The mean cumulative 24-h i.v. PCA morphine requirement in the 2-CP, 2-CP+Epi and Lido+Epi groups respectively was 20.5±24, 33.1.5±27 and 4.07±6.3 (mean±SD). The Lido+Epi group used significantly less morphine ( P = 0.01) compared to either of the 2-CP groups with no significant difference between the 2-CP groups. The maximum i.v. PCA morphine use occurred in the first 4 hours following surgery in all three groups.
Conclusion: Analgesic efficacy of EM is decreased when 2-CP is used for LEA compared to when Lido+Epi is used. 相似文献
Methods: Forty-two patients scheduled for elective CS were randomly divided into 3 equal groups, and received 2-CP, 2-CP+epinephrine (Epi, 5 μg ml
Results: The mean cumulative 24-h i.v. PCA morphine requirement in the 2-CP, 2-CP+Epi and Lido+Epi groups respectively was 20.5±24, 33.1.5±27 and 4.07±6.3 (mean±SD). The Lido+Epi group used significantly less morphine ( P = 0.01) compared to either of the 2-CP groups with no significant difference between the 2-CP groups. The maximum i.v. PCA morphine use occurred in the first 4 hours following surgery in all three groups.
Conclusion: Analgesic efficacy of EM is decreased when 2-CP is used for LEA compared to when Lido+Epi is used. 相似文献
76.
77.
作利用复合致痛剂引起大鼠尾部皮肤多觉型伤害性感受器(PMN)持续性放电模型,经股静脉注入吗啡(4mg/kg),显抑制PMN持续性放电。吗啡抑制PMN放电50%的潜伏期为10±4.5min,抑制时程超过30min。纳络酮1mg/mg iv,可翻转吗啡的抑制作用。在慢性吗啡耐受大鼠,吗啡几乎失去其抑制作用。吗啡引起的PMN放电数变化不呈一致关系。小剂量吗啡(1mg/kg)注入支配感受野皮肢的尾动脉 相似文献
78.
Thrombin Inhibition in discordant xenograft rejection 总被引:1,自引:0,他引:1
Beth-Ann Lesnikoski Daniel Candinas Ichiro Otsu Rainer Metternich Fritz H. Bach Simon C. Robson 《Xenotransplantation》1997,4(3):140-146
Abstract: Microvascular thrombosis and the associated platelet and endothelial cell activation are prominent observations in xenograft rejection. This pathological picture could be related to the excessive generation of thrombin in the context of either inflammation or putative inter-species molecular incompatibilities between activated coagulation factors and their natural anticoagulants. Relatively selective thrombin Inhibition with the serine protease inhibitor SDZ MTH 958 (MTH-958) are independent of heparinoids and anti-thrombin III. MTH-958 has been shown to significantly prolong porcine cardiac function during perfusion with human blood in an ex vivo model. The aim of this study was to validate the role of thrombin generation in a rodent model of discordant xenograft rejection in vivo. The effect of thrombin inhibition with MTH-958 was tested in both hyperacute rejection (HAR) and delayed xenograft rejection (DXR) after decomplementation with cobra venom factor (CVF) in normal Lewis (Lew) rats and Intrinsic C6 deficiency In PVG (C6-/PVG) recipient rats. Recipient rats received heterotopic guinea pig cardiac xenografts and were treated with titrated doses of MTH-958 until the time of graft rejection. Plasma samples at selected time points were examined to confirm effective thrombin inhibition, and rejected grafts were analyzed by immunohistology. MTH-958 significantly improved graft survival in HAR albeit the extent of prolongation was not marked, but the agent failed to prolong survival In CVF-treated Lew rats. In C6-/PVG rats receiving MTH-958, a significantly reduced graft survival time was observed when compared with C6-/PVG controls. The grafts from MTH-958-treated animals showed dense deposits of C3, IgM, and IgG with fibrin levels similar to controls. The thrombin antagonist tested could prolong xenograft survival during HAR but had no benefit in DXR. The relative non-specificity of the serine protease inhibitor MTH-958 with the potential activation of alternative pathway of complement via the inhibition of factor I could account for the failure to prolong xenograft survival in DXR. The pathogenetic significance of thrombin generation in this situation remains to be determined by the use of more selective and pharmacologically acceptable I anti-thrombin agents. 相似文献
79.
①目的 观察心痛灵喷雾剂对心肌缺血大鼠的药理作用。②方法 通过结扎大鼠冠状动脉前降支制备大鼠心肌缺血模型 ,观察心痛灵喷雾剂对心肌缺血面积和血清磷酸肌酸激酶 (CK)、乳酸脱氢酶 (LDH)、谷草转氨酶 (GOT)的影响 ;静脉注射垂体后叶素制备大鼠心肌缺血模型 ,观察心痛灵喷雾剂对心电图改变的影响。③结果 心痛灵喷雾剂可减少心肌缺血大鼠心肌梗死面积 ,降低血清CK、LDH、GOT活性 ,并减轻静脉注射垂体后叶素引起的缺血性心电图改变 (tD=1.2 2 3~ 13.890 ,P <0 .0 5、0 .0 1)。④结论 心痛灵喷雾剂具有抗心肌缺血的作用 相似文献
80.