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41.
Byong Kak Kim Eung Chil Choi Kyeong Soo Chung Hee Ju Park Hye Ryoung Kim Yang Sup Kim Yong Hwan Park Mi Ja Shim 《Archives of pharmacal research》1983,6(2):141-142
To find antitumor metabolites in Korean basidiomycetes, the shake-cultured mycelia of eight of the higher fungi were extracted with hot water and the extracts, after being partially purified, were subjected toin vivo antitumor test. When administeredi.p. at the dose of 30mg/kg/day for ten consecutive days into the female ICR mice, which had been implanted with 1×105 cells of sarcoma 180 twenty-four hours before the first injection, the extracts ofAgaricus campestris, Lyophyllum decastes, Lyophyllum ulmarium, Armillaria tabescence andCalvatia exipulitormis respectively showed inhibition ratios of 64.1%, 65.4%, 60.0%, 53.0% and 49.3%. These five species were selected for further study, whereas the extracts ofPhallus impudicus, Coprinus comatus andPholiota squarrosa which showed the inhibition ratios of 31.2%, 33.5% and 19.0% were discontinued. 相似文献
42.
Selective neuronal survival and upregulation of PCNA in the rat inner retina following transient ischemia 总被引:1,自引:0,他引:1
Ju WK Kim KY Hofmann HD Kim IB Lee MY Oh SJ Chun MH 《Journal of neuropathology and experimental neurology》2000,59(3):241-250
In this study we investigated the extent and time course of neuronal cell death and the regulation of the proliferating cell nuclear antigen (PCNA) in the different retinal cell layers following ischemia-reperfusion injury. Retinal ischemia was induced by controlled elevation of the intraocular pressure for a duration of 60 min. Changes in thickness and cell numbers in the retinal cell layers were analyzed at various time points (1 h to 4 weeks) after reperfusion. In parallel, apoptotic cell death was determined by the TUNEL method and the expression of PCNA analyzed by immunocytochemistry. In addition, we tested whether PCNA is expressed in neurons by double immunocytochemistry. The reduction in thickness was found to be less pronounced in the inner nuclear layer (INL). Correspondingly, cell numbers decreased by only 33% in the inner retina, but by more than 80% in the outer nuclear layer (ONL). Alterations in glial cell numbers did not contribute significantly to postischemic changes in the INL and ONL as assessed by using immunocytochemical markers for microglial and Müller cells. The time course of cell death determined by the TUNEL technique also differed markedly in the retinal layers being rapid and transient in the inner retina but delayed and prolonged in the ONL. PCNA immunoreactivity was undetectable in the normal retina, but was specifically induced in neurons of the inner retina within 1 h after reperfusion and was sustained for at least 4 weeks. We conclude that in contrast to photoreceptors in the ONL, a significant proportion of inner retinal neurons is resistant to ischemic insult induced by transiently increased intraocular pressure and that PCNA may possibly play a role in the selective postischemic survival of these cells. 相似文献
43.
44.
目的:探讨经鼻持续气道正压通气(nCPAP)治疗,对阻塞性睡眠呼吸暂停综合征(OSAS)合并高血压患者动态血压的影响。方法:22例男性患者行多导睡眠图(PSG)监测及动态血压检查确诊为OSAS合并高血压的患者,观察nCPAP治疗前后患者动态血压、多导睡眠图等多项指标变化。结果:nCPAP治疗后患者PSG参数明显改善:睡眠时最低SaO_2从(71.0±12.3)%上升到(91.7±7.3)%(P<0.01);RDI显著降低;同时24小时血压明显下降,治疗前血压(16.5±1.6/11.6±2.3Kpa),治疗后血压(13.7±1.5/9.3±1.4Kpa)(P<0.01)。结论:经鼻持续气道正压通气治疗阻塞性睡眠呼吸暂停综合征,不但可以纠正患者的呼吸暂停,改善临床症状,而且可能降低患者的血压。 相似文献
45.
46.
土鳖虫水提物对实验性高脂血症大鼠血管内皮和内皮素的影响 总被引:19,自引:0,他引:19
目的研究土鳖虫水提物对高脂血症大鼠血管内皮和内皮素 (ET)的影响。方法建立高脂血症大鼠模型 ,测定血浆ET的浓度 ,并应用内皮细胞铺片和免疫组化相结合的方法 ,在大鼠主动脉内皮细胞铺片上 ,计数内皮细胞和ET阳性细胞并定量分析ET的合成。结果实验第 80d ,与正常组比较 ,高脂组血浆ET显著增高 (P <0 .0 1) ;内皮铺片显示内皮细胞数量增多 ,排列紊乱 ,胞核大小和染色深浅不一 ,ET阳性细胞率显著升高 (P <0 .0 1)。土鳖虫中、高剂量组血浆ET水平和ET阳性细胞率显著降低 (P <0 .0 5~ 0 .0 1)。结论土鳖虫水提物能保护血管内皮 ,减少ET的合成与释放 相似文献
47.
反相高效液相色谱法测定发酵液中梅岭霉素 总被引:1,自引:0,他引:1
目的:建立了发酵液中梅岭霉素的定量测定方法。方法:反相高效液相色谱法,Hypersil-C_(18)柱(4 mm×125mm,5μm),流动相为乙腈-水(78:22),流速1.2mL·min~(-1),检测波长238 nm,室温测定。结果:在1O.2~163.2μg·mL~(-1)范围内梅岭霉素浓度与峰面积呈良好线性关系,r=0.999 7,回归方程为Y=25.44X+2.72。样品的日间 RSD≤1.8%,高中低浓度样品的日内RSD≤2.5%(n=8)。平均回收率为96.9%(n=8,RSD<3.0%)。结论:本方法快速、准确、简便、稳定,为定量分析提供了可靠的依据。 相似文献
48.
Time-dependent astroglial changes after gamma knife radiosurgery in the rat forebrain 总被引:11,自引:0,他引:11
OBJECTIVE: Using an experimental rat model and a clinically relevant treatment dose, we performed gamma knife radiosurgery to define the hyperacute radiation effects in normal rat forebrain, the time dependence of the astrocytic reaction, and the participation of astrocytes in the healing process after single-dose gamma radiation injuries. METHODS: Seventy-one rats underwent radiosurgical treatment (4-mm collimator) of the caudate-putamen nucleus (single-fraction maximal dose of 100 Gy) and were killed at times ranging from 3 hours to 90 days. Serial cryostat brain sections were processed with the immunohistochemical avidin-biotin complex technique, using anti-glial fibrillary acidic protein as the primary antibody (to identify astrocytes). RESULTS: Vascular changes, including endothelial hyperplasia and vessel wall thickening, were identified as the earliest postradiation manifestations and continued throughout the observation period. Astrocytes reacted to the radiation injury with hyperplasia and hypertrophy. At earlier time points (3-24 h), proliferation was the predominant reaction. The expression of glial fibrillary acidic protein in the proliferating and hypertrophic astrocytes formed an initial peak in the adjacent corpus callosum 3 days after radiosurgery and peaked within the target site between 14 and 30 days. Astrocytic proliferation and hypertrophy were also observed in distant cortices (frontal, parietal, insular, and piriform cortices) and in the hippocampus. No necrosis was observed less than 30 days after irradiation. By Day 90, necrotic lesions with a mean diameter of 4 mm were identified, with glial scar at their peripheries. Astrocytic morphological features varied according to the distance from the necrosis. The irradiated side contained more glial fibrillary acidic protein-containing cells than did the nonirradiated contralateral side. CONCLUSION: During the early phase after radiation, vasculopathy was the first morphological change and may serve as the initiating factor for subsequent changes. Reactive astrocytes appeared not only at the target site but also in the surrounding regions; the severity of injury was determined by the distance from the target. 相似文献
49.
旋转手法对椎动脉血流平均速度的影响 总被引:4,自引:0,他引:4
目的 观察手法治疗椎动脉型颈椎病的经颅多普勒 (TCD)变化 ,从血流动力学角度探讨手法治疗的作用机制。方法 将 82例椎动脉型颈椎病患者随机分成手法治疗组 4 0例与常规治疗组 4 2例 ,治疗前及治疗后检查TCD ,观察手法治疗对椎动脉型颈椎病患者的血流平均速度的影响。结果 ① 82例患者治疗前椎基底动脉血流平均速度均明显低于正常参考值范围(P <0 .0 5 )。TCD异常率为 76 % ( 6 2 /82 )。②治疗后两组椎基底动脉血流速度均有改善。手法治疗组比常规治疗组椎动脉血流速度改善更明显 (P <0 .0 5 )。结论 手法治疗可以改善椎动脉型颈椎病椎基底动脉的血流速度。 相似文献
50.
Bachiller Burgos J Varo Solís C Báez JM Estudillo F Juárez Soto A Soto Delgado M Beltrán Aguilar V González Moreno D Sánchez Bernal C Rodríguez-Rubio F 《Actas urologicas espa?olas》2000,24(8):673-676
The existence of a vesical diverticulum in the context of a congenital connective tissue disorder such as Ehlers-Danlos syndrome led us to consider the possibility of a relationship. Four types of diverticula can be found in the literature: congenital, acquired, iatrogenic and syndrome-associated. Within the later, Ehlers-Danlos syndromes type IV and IX, even type V, are associated to the existence of vesical diverticula. The potential spontaneous rupture of the diverticulum is a typical feature, as well as post-surgery relapse. The attitude towards such diverticula should be one of watchful waiting, and simple, plasty-free diverticulectomy on the bladder's neck is indicated when performing a surgical procedure. 相似文献