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51.
The presence of morphologically distinct tissues within the adult bovine deep flexor tendon presented a model which we examined for correlations between proteoglycan content and tissue swelling properties. The proximal portion which experiences only tensile forces contained low levels of glycosaminoglycan (0.2% glycosaminoglycan hexosamine as percentage of dry weight) that were evenly distributed throughout its length and thickness. Collagen accounted for 80% of tissue mass, and collagen fibers formed parallel arrays running longitudinal to the direction of tensile force. In equilibrium bulk swelling tests, the properties of proximal tissue were uniform throughout the tissue and typical of collagenous tissues in which the response to equilibration in low ionic strength buffers or acid pH is dominated by the collagen network. The anterior aspect of the distal deep flexor tendon articulates with the stiff paratendinous sheath and sesamoid bones and is subjected to compressive and frictional forces in addition to longitudinal tensile forces. Along this anterior surface and extending partially into the tendon is tissue that resembles fibrocartilage with collagen fibers organized as a random network. Greatest glycosaminoglycan hexosamine contents (2-3% of dry weight) were found in the distal surface layer, and large proteoglycans were concentrated at the site receiving direct compressive and frictional loads. Equilibrium bulk swelling tests on distal tissue showed that the articulating surface layer possessed unique material properties. Distal surface layers swelled when counter ions were washed from the tissue, whereas lowered pH had little effect on distal tissue volume. Swelling properties of distal tissue correlated directly with proteoglycan content and were similar to swelling properties of articular cartilage. These results suggest that the articulating layer of distal flexor tendon is adapted for a unique set of mechanical requirements and that an elevated proteoglycan content at the site of compressive and frictional forces contributes to meeting these functional needs.  相似文献   
52.
1952~1987年收治158例腹部闭合性损伤单纯脾破裂患者,其中全脾切除135例;脾切除并自体脾组织移植21例,脾破裂缝合修补2例。治愈率为98.1%,死亡率为1.9%。脾移植组及缝合修补组无1例死亡。92例获得免疫功能检验随访观察半年至35年,发现成人切脾后细胞免疫及体液免疫功能无明显影响,也未见脾切除后严重感染发生。认为成人除脾破裂表浅和局限易于修复或部分切除者外,均应行脾切除术,且无需行自体脾组织移植。小儿在脾切除后应行自体脾移植。  相似文献   
53.
目的 分析 5种常用的肌腱保存方法对肌腱生物力学的影响。从生物力学的角度寻找最佳的保存方法 ,用于指导临床肌腱移植。方法 采用 5 0只健康白色Leghorn鸡 ,随机分成 5组 ,建立 2 ,3 ,4爪浅屈肌腱做供体模型。分别采用常用的保存组织方法 :低温冷藏 ,70 %酒精 ,10 %福尔马林 ,85 %甘油。结果 低温冷藏组在最大抗拉伸力Pmax及最大延伸率δmax与新鲜肌腱组比较 ,无明显差异。酒精组、85 %甘油组最大抗拉伸力较高 ,而福尔马林组最低。结论 低温冷藏的方法保存肌腱 ,从生物力学角度考虑是最佳的保存方法  相似文献   
54.
Ruptures of the hepatic artery and hepatic pseudoaneurysms (PA) are rare but serious complications of hepatic transplantation. We conducted a retrospective study of 640 liver transplantations performed in our institution for a variety of pathologies. After surgery, seven major arterial bleeds occurred (0.9%). Of these seven cases, there were due to hepatic artery rupture (HAr) and four to PA rupture; all confirmed at either surgery (six cases) or autopsy (one case). Five of the seven patients died. In all cases the transplantation was difficult. All vascular injuries but one were caused by sepsis and occurred either after an undetermined cause septicemic syndrome (five cases) or graft dysfunction (one case). The last vascular injury was biliary drainage related. Six of the seven patients had imaging studies. Sonography (five cases) found a sub-hepatic hypoechoic collection in three cases but failed to do so in two. Duplex doppler (three cases) failed in all three cases to demonstrate a PA. Computed tomography (three cases) showed one PA, one perihilar sub-hepatic collection and failed in one. Conventional angiography (three cases) depicted a PA in all three cases. At the present time, our practice is to perform systematic angiography in patients with undetermined cause septicemic syndrome to research a PA. And if angiography is normal, to then puncture systematically any sub-hepatic collection to determine the bacteriological nature of this collection. Correspondence to: H. Caillet  相似文献   
55.
The concept of partial rupture of the anterior cruciate ligament (ACL) has been confirmed by arthroscopic examination and palpation. We present a prospective study of 43 patients who were diagnosed arthroscopically as suffering from a partial rupture of the ACL by the same surgeon. The patients followed a rehabilitation protocol and were examined by an independant observer after 5 years. Twenty-five patients had a stable knee, whereas 18 eventually suffered a complete ACL rupture. ACL partial rupture is easily recognizable with arthroscopy, but the quantity and state of the still intact fibres is difficult to assess. Received: 20 April 1996 Accepted: 17 December 1996  相似文献   
56.
57.
Severe aortic regurgitation was discovered in a young man 21 days after blunt chest trauma and after a prolonged febrile state with positive blood cultures. Using transoesophageal echocardiography (TEE), it was possible to make the differential diagnosis between traumatic rupture and endocarditis as the cause of valvular insufficiency. The use of TEE in the initial evaluation of severe thoracic trauma with an unclear clinical picture is recommended. This method is easy to use at the bedside and gives precise information on the aortic valve and the ascending aorta.  相似文献   
58.
Nerve regeneration during healing of Achilles tendon rupture in the rat was studied by immunohistochemistry including semi-quantitative assessment. Neuronal markers for regenerating and mature fibers, ie., growth associated protein 43 (GAP-43) and protein gene product 9.5 (PGP 9.5), respectively, were analyzed at different time points (1-16 weeks) post-rupture. In the paratenon, both the ruptured and intact contralateral tendon (control) consistently exhibited immunoreactivity to the two neuronal markers. However, in the proper tendinous tissue only the ruptured tendon showed immunoreactivity to GAP-43 and PGP 9.5. This expression was seen already at week 1 post-rupture to reach a peak at week 6 followed by a successive drop till week 16. Also the occurrence of sensory and autonomic fibers according to immunoreactivity for calcitonin gene-related peptide (CGRP) and neuropeptide Y (NPY), respectively, was analyzed. CGRP-positivity was abundantly seen from weeks 2-6 in both perivascular and sprouting free nerve endings in the proper tendon tissue undergoing healing. NPY appeared later, at weeks 6-8 post-rupture around blood vessels mainly located in the surrounding loose connective tissue. Apart from a role in vasoaction (CGRP, vasodilatory; NPY, vasoconstrictory). both neuropeptides have been implicated in fibroblast and endothelial cell proliferation required for angiogenesis. The present study shows that early healing of ruptured tendons is characterized by an orchestrated, temporal appearance of nerve fibers expressing peptides with different actions. The observed pattern of neuronal regeneration and neuropeptide expression may prove to be important for normal connective tissue healing.  相似文献   
59.
新生儿胃穿孔18例诊治报告   总被引:2,自引:0,他引:2  
目的 :探讨新生儿胃穿孔的诊断、治疗效果及预后因素。方法 :对 1 8例新生儿胃穿孔病例诊断、治疗及预后因素进行分析。结果 :1 8例患儿均有拒奶、腹胀、呕吐、呼吸困难等症状。腹部立位 X线片示膈下有大量游离气体。其中单纯穿孔 6例 ,多发穿孔 4例 ,胃壁缺损 7例 ,全胃壁缺如 1例。单纯及多发胃穿孔行胃修补术 ,3例同时行胃造痿术。胃壁肌层缺损行病变组织切除、胃壁修补及胃造痿术。 1例全胃壁肌层缺如仅行腹腔引流术。本组存活 8例 ;死亡 1 0例 ,病死率 5 5 .5 6%。死亡原因为多脏器功能衰竭、DIC。结论 :新生儿胃穿孔预后差 ,且受发病时间、就诊时间、病变严重程度等综合因素影响  相似文献   
60.
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