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991.
输卵管切除术对超排卵的影响 总被引:1,自引:0,他引:1
目的:探讨单侧输卵管切除,切除侧卵巢对超排卵的反应性。方法:以因输卵管妊娠行单侧输卵管切除后不孕接受IVF-ET治疗的患者45例共52个周期为研究组,并以同期因输卵管阻塞(无输卵管积水)不孕行IVF-ET治疗的患者875例共913个周期为对照,分析输卵管切除侧卵巢与对侧卵巢对超排卵的反应性。结果:①两组的促性腺激素(Gn)用量、用药天数、hCG日E_2水平、卵裂率、平均移植胚胎数、种植率、临床妊娠率、流产率、异位妊娠率差异无统计学意义(P>0.05)。但单侧输卵管切除组的获卵数减少,差异有统计学意义(P<0.05)。②研究组卵泡晚期(注射hCG日)两侧卵巢大小(分别为35.1±6.5mm、38.2±5.9 mm)有差异,P<0.05。取卵日两组卵泡数(个)分别为6.7±4.5、8.6±3.3(P<0.05),回收卵子数(个)分别为4.9±3.7、6.4±3.6,P<0.05。结论:单侧输卵管切除者切除侧卵巢在行超排卵时,其卵泡晚期(注射hCG日)卵巢较小,取卵日的卵泡数和回收卵子数明显减少,手术可能影响卵巢的血液供应和超排卵效果。 相似文献
992.
Driver Sleepiness and Risk of Car Crashes in Shenyang, a Chinese Northeastern City: Population-based Case-control Study 总被引:1,自引:0,他引:1
Liu GF Han S Liang DH Wang FZ Shi XZ Yu J Wu ZL 《Biomedical and environmental sciences : BES》2003,16(3):219-226
Objective To estimate the association of driver sleepiness with the risk of car crashes. Methods A population-based case-control study was conducted in Shenyang, a northeastern city in China, between November 2001 and July 2002. The case group comprised 406 car drivers involved in crashes, and 438 car drivers recruited at randomly selected sites, and on the day of week, and the time of day when they were driving on highways in the study region during the study period were used as control groups. Face-to-face interviews with drivers were conducted according to a well-structured questionnaire covering the circumstances of their current trip and their background information. Stanford sleepiness scale and Epworth sleepiness scale were used to quantify acute sleepiness and chronic sleepiness respectively. Results There was a strong association between chronic sleepiness and the risk of car crash. Significantly increased risk of crash was associated with drivers who identified themselves as sleepy (Epworth sl 相似文献
993.
目的 了解硬质树脂贴面与三种粘结剂的粘结强度。方法 选用21颗中切牙随机分成三组(n=7),制作硬质树脂贴面,用不同的粘结剂粘固。第1组:EM釉质粘结剂;第2组:京津釉质粘合剂;第3组:光固化树脂,粘结后置入37℃温水中24小时后,用电子多功能测试机进行拉伸试验。结果 三种粘结剂与硬质树脂粘结拉伸强度无差异,光固化树脂与硬质树粘接力大于与釉质的粘接力,京津釉质粘结剂与硬质树脂粘结力小于与釉质的粘接力;EM釉质粘结剂与硬质树脂和釉质的粘结力近似一个水平。结论 三种粘结剂粘接硬质树脂贴面是可行的。 相似文献
994.
目的探讨非霍奇金淋巴瘤 (NHL)中丙型肝炎病毒 (HCV)的感染与P5 3表达的相关性及其意义。方法应用免疫组织化学S P法对 133例NHL和 2 5例良性淋巴组织病变 (BLPC)进行P5 3及HCVTORDJI 2 2蛋白的检测 ,对其中 5 8例NHL和全部BLPC进行HCVRNA的原位RT PCR检测。结果HCV感染阳性共 17例 (TORDJI 2 2阳性 9例 ,HCVRNA阳性 11例 ,双阳性 4例 ) ,感染阳性率为 12 8% (17/ 133) ,BLPC中HCV感染阴性 ,两组比较差异有显著性 (P <0 0 5 )。NHL中P5 3阳性 71例 (5 3 4 % ) ,BLPC中P5 3均为阴性。 17例HCV阳性NHL中P5 3阳性 13例 (P <0 0 5 )。结论 (1)HCV感染与NHL之间有相关性 ;(2 )HCV可能通过调控P5 3的表达而参与NHL的发生。 相似文献
995.
996.
L-精氨酸、L-硝基精氨酸对红藻氨酸诱导大鼠癫痫及其海马结构中iNOS mRNA表达的影响 总被引:2,自引:0,他引:2
目的 观察诱导型一氧化氮合酶 (iNOS)在红藻氨酸(KA)癫痫大鼠海马内的表达及L 精氨酸 (L Arg)和L 硝基精氨酸 (L NNA)慢性干预的影响。方法 采用惊厥剂量的KA(1 0mg·kg- 1 )诱导大鼠癫痫发作 ,以NOS抑制剂L NNA(50mg·kg- 1 )和NO前体L Arg(40mg·kg- 1 )进行干预 ,对大鼠的癫痫发作行为及KA后不同时间点的海马内i NOSmRNA ,通过RT PCR观察其表达。结果 KA可使动物发生时间相关性癫痫发作 ,L NNA预处理后使KA诱导的癫痫发作明显加重 ,而L Arg预处理后使KA诱导的癫痫发作减弱。iNOSmRNA在KA处理后 3h开始有微弱的表达 ,且随着时间的延长逐渐增加 ,2 4h达到最高水平 ,2d及3d时未见表达 ,但 7d时又出现高表达 ;经L NNA预处理的动物 ,KA后 1h其海马结构中未出现iNOSmRNA ,但L Arg预处理后再给予KA后 1h ,可见微弱的iNOSmRNA表达。结论 红藻氨酸给药后一定时间 ,癫痫大鼠海马结构中可出现iNOSmRNA表达 ,L Arg慢性干预也有一定影响 相似文献
997.
Responses of antioxidant systems in the hepatocytes of common carp (Cyprinus carpio L.) to the toxicity of microcystin-LR. 总被引:9,自引:0,他引:9
The freshwater, bloom-forming cyanobacterium (blue-green alga) Microcystis aeruginosa produces a peptide hepatotoxin, which causes the damage of animal liver. Recently, toxic Microcystis blooms frequently occur in the eutrophic Dianchi Lake (300 km2 and located in the South-Western of China). Microcystin-LR from Microcystis in Dianchi was isolated and purified by high performance liquid chromatography (HPLC) and its toxicity to mouse and fish liver was studied (Li et al., 2001). In this study, six biochemical parameters (reactive oxygen species, glutathione, superoxide dismutase, catalase, glutathione peroxide and glutathione S-transferase) were determined in common carp hepatocytes when the cells were exposed to 10 microg microcystin-LR per litre. The results showed that reactive oxygen species (ROS) contents increased by more than one-time compared with the control after 6 h exposure to the toxin. In contrast, glutathione (GSH) levels in the hepatocytes exposed to microcystin-LR decreased by 47% compared with the control. The activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxide (GSH-Px) increased significantly after 6 h exposure to microcystin-LR, but glutathione S-transferase (GST) activity showed no difference from the control. These results suggested that the toxicity of microcystin-LR caused the increase of ROS contents and the depletion of GSH in hepatocytes exposed to the toxin and these changes led to oxidant shock in hepatocytes. Increases of SOD, CAT and GSH-Px activities revealed that these three kinds of antioxidant enzymes might play important roles in eliminating the excessive ROS. This paper also examined the possible toxicity mechanism of microcystin-LR on the fish hepatocytes and the results were similar to those with mouse hepatocytes. 相似文献
998.
Yuansheng Tan Daming Li Renjie Song David Lawrence David O Carpenter 《Toxicological sciences》2003,76(2):328-337
The effects of exposure of acutely dissociated rat thymocytes to various polychlorinated biphenyl (PCB) congeners were examined using flow cytometry. Non-planar, ortho-substituted congeners caused a rapid cell death at low micromolar concentrations, while coplanar, dioxin-like congeners at the same concentration were without significant effect. The most potent of the congeners studied was PCB 52 (2,2',5,5'-tetrachlorobiphenyl), which had an IC50 of 3.96 microM at 20 min. Prior to loss of viability there was a decrease in mitochondrial membrane potential Delta Psi m, an accumulation of intracellular calcium, and a progressive leakiness of the plasma membrane. Application of PCB 52 in calcium-free medium reduced the calcium accumulation, but did not reduce cell death. Agents that depolarized mitochondria also did not induce the same degree of cell death caused by PCB 52. Cyclosporin A, which prevents opening of the mitochondria permeability transition channel, protected against cell death but did not protect against mitochondrial depolarization or calcium accumulation. Rapamycin and FK 506 at high concentration provided partial protection against cell death. These observations indicate that the ortho-substituted PCB 52 disrupts plasma, mitochondrial and endoplasmic reticulum membranes. We hypothesize that PCB 52 incorporates into lipid bilayers and with its bulky, three-dimensional ortho-substituted congener structure disrupts membrane function to a greater degree than coplanar congeners. 相似文献
999.
1000.
目的分离鉴定蘡Ao地上部分的化学成分。方法通过硅胶柱色谱,Sephadex LH-20及制备HPLC方法分离,对其进行理化常数和光谱分析确定结构。结果自蘡Ao地上部分分离得到11个多酚化合物,均属首次分离。结论化合物1为新化合物,经鉴定其结构为3,5-二甲氧基-4-羟基苯丙醇-9-氧-β-D-吡喃葡萄糖苷。 相似文献