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191.
Revascularization of the hypogastric artery often tends to be neglected in aortoiliac reconstructive surgery; however, its
incomplete revascularization can result in unfavorable complications such as buttock claudication or necrosis, vascular impotence,
and colonic ischemia. Multiple vascular lesions in the abdominal aorta and bilateral iliac arteries were reconstructed using
a newly designed double bifurcated graft in five male patients. All five patients demonstrated excellent graft limb patency
and postoperative improvement of the ankle-brachial pressure index without any clinical signs of ischemia in regions of the
hypogastric artery. Thus, we conclude that an aggressive approach toward hypogastric circulation maintenance is essential
in aortoiliac reconstructive surgery. By using this double bifurcated graft, rapid and safe revascularization of the bilateral
hypogastric arteries concomitant with the external iliac or femoral arteries can be performed. 相似文献
192.
This article describes the evolving role of echocardiography for the detection and evaluation of thoracic aortic aneurysms. A brief summary of the clinical, anatomical, and pathological features of the etiologic categories of thoracic aneurysms is presented. The advantages and limitations of echocardiography and its comparison with other techniques (computed tomographic scanning, magnetic resonance imaging, and aortography) are discussed. 相似文献
193.
Tetsuo Hadama Yoshiaki Mori Osamu Shigemitsu Tatsunori Kimura Shinji Miyamoto Hidenori Sako Tooru Soeda Toshihide Yoshimatsu Yuzo Uchida 《Surgery today》1996,26(1):60-63
We report herein the rare case of a 79-year-old man who suffered permanent paraplegia after undergoing an otherwise successful total arch replacement for a ruptured aortic arch aneurysm. During cardiopulmonary bypass, perfusion to the distal aorta was maintained from the femoral artery, and postoperative aortography showed intact tributaries from the aorta including the intercostal arteries. Postoperative paraplegia is an extremely rare complication of operations on the aortic arch; however, we speculate that the paraplegia in this patient could be attributed either to a steal phenomenon involving the radicular artery, or to the anatomical particularity of the spinal cord artery described by Cole and Gutelius as the segmental system. 相似文献
194.
Effect of continuous cisternal drainage on cerebral vasospasm 总被引:3,自引:0,他引:3
Summary The effect of continuous cisternal drainage on cerebral vasospasm was studied under strict criteria in 140 patients with ruptured intracranial aneurysms. The degree of subarachnoid haemorrhage (SAH) on the computed tomography scan was graded from I to IV. The patients were classified according to the total amount of cisternal drainage into three groups, regardless of the duration of the drainage and whether or not it was accompanied by irrigation; i.e., those with less than 500 mL (group 157 cases), those with 500–3000 mL (group 2 44 cases), and those with 3000–9500 mL (group 3 39 cases).While correlations could be found between both clinical and SAH grades with the severity of vasospasm, closer correlation could be found in the SAH grades. In analyzing the cases with subarachnoid haemorrhage grades III–IV (severe clots), the angiographic vasospasm was less severe in groups 2 and 3 than in group 1, and the incidences of permanent symptomatic vasospasm and low-density area on computed tomography were lower in groups 2 and 3 than in group 1. Regarding the surgical outcome in cases with SAH grades III–IV, the mortality rate was lower in groups 2 and 3 (22% and 19%) than in group 1 (33%). Further, the rate of good recovery was higher in groups 2 and 3 (61% and 57%) than in group 1 (28%). However, there were no differences between groups 2 and 3 in cerebral vasospasm or in surgical outcome. As a shortcoming of continuous cisternal drainage, the need for shunt operation was higher in groups 2 and 3 than in group 1. 相似文献
195.
P. De Marinis A. Punzo M. Colangelo G. Ruggiero A. De Simone A. Ambrosio 《Child's nervous system》1991,7(6):353-355
A giant aneurysm of the right callosomarginal artery is reported in a 3-month-old child. This location is rare: including our case reported here, only three cases have been described. Clinicoradiological findings are presented and the surgical procedure is illustrated. 相似文献
196.
我院自1982年~1988年共收治13例颈内动脉-后交通动脉瘤。本文就该处动脉瘤的临床诊断、手术入路以及动脉瘤破裂的预防和处理进行了讨论。 相似文献
197.
红花水煎剂对家兔离体主动脉血管的舒张作用 总被引:11,自引:0,他引:11
目的 观察红花Carthamustinctorius (DFCT)水煎剂对血管肌条的舒张作用及机制。方法 将家兔离体主动脉肌条放置于灌流肌槽中 ,记录其等长收缩。结果 DFCT对血管肌条静息张力无明显影响 ,但 2 0mg/mLDFCT水煎剂与 10 -5mol/L乙酰胆碱相似 ,可使 10 -6mol/L去甲肾上腺素预收缩血管肌条产生明显的舒张作用。去除内皮细胞、10 -4mol/LL NNA或 10 -5mol/L甲烯蓝可减弱DFCT的舒张血管作用 ,但前列腺素合成抑制剂和 β肾上腺素能受体阻断无明显影响。另外 ,4 0mg/mLDFCT水煎剂可明显抑制去内皮血管肌条去甲肾上腺和KCl的量效收缩反应 ,使其PD2 值分别由对照组 6 0 6± 0 0 9和 1 71± 0 33变为 5 0 7± 0 0 8和 1 35± 0 2 0。结论DFCT水煎剂可通过受体操纵Ca2 + 通道和电压依赖性Ca2 + 通道抑制外Ca2 + 内流 ,使血管肌条舒张 ,其作用与内皮释放的NO有关。 相似文献
198.
金粉蕨素抑制大鼠主动脉平滑肌增殖作用及机制 总被引:2,自引:0,他引:2
目的 :观察金粉蕨素对牛血清刺激的大鼠主动脉平滑肌细胞增殖的抑制作用 ,并对其作用机制进行初步探讨。方法 :体外培养大鼠主动脉平滑肌细胞 ,以终浓度为 10 %的新生牛血清 (NCS)作为刺激因素 ,用噻唑蓝 (MTT)比色法和细胞计数法观察细胞增殖状况 ,用流式细胞仪分析细胞周期 ,用Westernblot实验测定蛋白表达。结果 :与 10 %牛血清组相比 ,不同浓度金粉蕨素组的MTT测定值与细胞数目均明显下降 (P <0 .0 5 ) ,其下降幅度呈浓度依赖性 ;10 μmol·L-1时达峰值 (P <0 .0 1) ;细胞周期分析显示 ,金粉蕨素组G1期百分比 (85 .1% )高于10 %牛血清组 (70 .0 % ) ,而S期比例 (4 .3% )低于10 %牛血清组 (16.4 % ) ;Westernblot结果显示给药组P ERK1 2蛋白表达明显低于同时间点牛血清组。结论 :金粉蕨素能阻止细胞周期由G0 G1期向S期推进 ,抑制血管平滑肌细胞增殖 ,此作用与其抑制ERK1 2磷酸化、影响MAPK ERK通路激活有关。 相似文献
199.
Surgery of basilar aneurysms associated with unexpected rupture of an internal carotid artery aneurysm 总被引:1,自引:0,他引:1
During a surgery of basilar aneurysms via the trans-sylvian approach, we encountered an arterial bleeding caused by rupture
of an internal carotid artery aneurysm that had been difficult to diagnose before surgery, as it was a small and brood-neck
aneurysm and mimicked arteriosclerosis. In spite of several surgical procedures, the surgical path at the basilar aneurysms
became narrow, and we had to abandon the clipping of the aneurysms. Consideration of radiological and intraoperative findings
was made for this case, demonstrating a pitfall that neurosurgeons may encounter during surgery.
Received: 16 December 1998 / Accepted: 26 May 1999 相似文献
200.
Thrombus formation and hemolysis have been linked to the dynamic flow characteristics of heart valve prostheses. To enhance our understanding of the flow characteristics past the aortic position of a Jellyfish (JF) valve in the left ventricle, in vitro laser Doppler anemometry (LDA) measurements were carried out under physiological pulsatile flow conditions. The hemodynamic performance of the JF valve was then compared with that of the St. Vincent (SV) valve. The comparison was given in terms of mean systolic pressure drop, back flow energy losses, flow velocity, and shear stresses at various locations downstream of both valves and at cardiac outputs of 3.5 L/min, 4.5 L/min, and 6.5 L/min respectively. The results indicated that both valves created disturbed flow fields with elevated levels of turbulent shear stress as well as higher levels of turbulence in the immediate vicinity of the valve and up to 1 diameter of the pipe (D) downstream of the valve. At a location further downstream, the JF valve showed better flow characteristics than the SV in terms of velocity profiles and turbulent shear stresses. The closure volume of the SV valve was found to be 2.5 times higher than that of the JF valve. Moreover, the total back flow losses and mean systolic pressure drop also were found to be higher in the SV than the JF valve. 相似文献