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101.
迄今,在已知的人类病毒性肝炎中,乙、丙、丁、戊、庚等5种肝炎病 毒已被证实能经垂直传播而导致婴儿罹患肝炎综合征。最近报告甲型肝炎病毒(HAV)也能引 起母婴垂直传播[1~2]。但由日本学者Nishizawa等(1997)发现的输血传播病毒(T TV)经多项研究表明垂直传播机率不大[3~5]。本文介绍近年来对乙型肝炎病毒( HBV)垂直传播研究所取得的一些进展。 1 HBV垂直传播机率   婴幼儿中80%的HBV感染者是经垂直传播而得。HBsAg和HBeAg阳性母亲有80%~90%的可能会将 其病毒传给后代,其中85%以上会成为HBsAg携带者,而HBsAg(+)HBeAg(-)母亲的HBV传播率 只有2%~5%[6]。Soderstrom等[7]报告在HBV低度流行的瑞典检测了93 例儿童,其中90例(96.8%)HBV DNA(+),54例(58%)HBeAg(+)。93例儿童有81例(87%)来源于 高/ 中度HBV流行区,12例(13%)  相似文献   
102.
不同材料双J管对兔输尿管的影响   总被引:10,自引:1,他引:9  
目的:观察不同材料双J管对兔输尿管的影响。方法:本实验通过三种双J管置于15例(每一种双J管5例)正常兔的输尿管内,6周后观察其对输尿管上皮的损伤,输尿管的反应变化,双J管长壳的程度,置管前后肾盂压力的变化,结果:三种双J管均产生上皮细胞的损伤,二种国产双J管所引起的输尿管反应性较小。而进口双J管较重,与之相反,国产双J管长结古石的程度远较进口双J管严重(P<0.05),置管6周后与管前比较肾盂压力无明显变化(P<0.05),结论:国产双J管有较严重的长结石的倾向,但输尿管的反应性变化较小,适合于短时间置管,进口双J管的输尿管反应性变化较重,便有较长长结石倾向,比较适合于篚置管,尽管这些为动物实验所得结果,但也可能与临床有关系。  相似文献   
103.
薄层扫描法测定安神宁康胶囊中黄芪甲甙的含量   总被引:4,自引:0,他引:4  
目的:建立测定安神宁康胶囊中黄芪甲甙含量的方法。方法:以氯仿——甲醇——水(65:35:10)的下层为展开剂,用双波长薄层扫描仪测定。结果:黄芪甲甙在1.049μg-5.245μg与峰面积积分值,呈良好的线性关系(r=0.9993,n=5),平均回收率为96.24%。结论:为控制安神宁康胶囊中黄芪甲甙的含量提供了方法。  相似文献   
104.
目的 用自制的钙离子选择性微电极(Ca^2 -ISME)测定游离钙,拟反映体内钙被吸收的真实水平。方法 建立了血清样品中钙离子测定方法,并进行三种具有代表意义的站钙剂的大鼠药代动力学对比研究。经灌胃给药,定时取血,制备血清并测定其钙离子浓度。结果 三种制剂在血中的达峰时间不完全一致,但其AUC间经t检验无显著性差异。结论 C^2 -ISME可用于钙制剂的药物代谢动力学研究。  相似文献   
105.
目的 :应用苄基二甲基十四烷氯化铵 (benzyldim ethyltetradecyl amm onium chloride,BAC)建立犬下食管括约肌(L ES)无神经动物模型 ,研究一氧化氮 (NO)对 L ES压力的作用。方法 :将 BAC环周注入犬 L ES,对照组注入等量生理盐水 ,均于注射前及注射后 6周测定 L ES压力 ;并观察 L -精氨酸、D -精氨酸、硝普钠及一氧化氮合酶 (NOS)抑制剂 N-硝基 - L -精氨酸 (L - NNA)对 L ES压力的影响 ;此外还测定了两组犬 L ES中 NO含量和 NOS活性。结果 :BAC处理组 L ES压力 [(4 2 .43±4.19) m m Hg,1m m Hg=0 .133 k Pa]显著高于对照组 [(2 2 .71± 5 .19) mm Hg]。 L -精氨酸可使对照组 L ES压力降低 ;L - NNA使其增高 ,但对 BAC处理组 L ES压力均无影响。硝普钠可降低两组犬 L ES压力。对照组 L ES中 NO为 (6 .0 5 8± 2 .0 6 7)μm ol/g,NOS为 (1.45 8± 0 .146 ) U /mg;而 BAC处理组 NO为 (1.797± 0 .873)μmol/g,NOS为 (0 .46 3± 0 .0 39) U /m g,均较对照组显著降低 (P<0 .0 1)。 结论 :BAC可使犬 L ES压力增高 ,其机制可能与 L ES局部 NO减少有关。  相似文献   
106.
Xiao  Bihuan  Jiang  Yuan  Wang  Bin  Hu  Yang  Sun  Yan  Wu  Yan  Qiao  Shuai 《Lasers in medical science》2021,36(6):1261-1266
Lasers in Medical Science - Large-scale long-term retrospective study of noninsulated microneedle radiofrequency treatment on neck rejuvenation is lacking. We conducted a 3-year retrospective...  相似文献   
107.
Wang  Jue  Wu  Jiang  Xu  Minghuo  Gao  Quanwen  Chen  Baoguo  Wang  Fang  Niu  Hao  Song  Huifeng 《Lasers in medical science》2021,36(6):1275-1282

The focus of treatment of faciocervical scar contractures includes cervical reconstruction and elimination of hypertrophic scars. Unfortunately, most previous studies have neglected the esthetic appearance of scars. In this study, we tried to combine surgical therapy and ultrapulse fractional CO2 laser (UFCL) to eliminate facial scars while restoring neck reconstruction and to establish the optimal conventional management for faciocervical contracture. Thirty-eight individuals were enrolled and divided into two groups. After received cervical release surgeries, comprehensive UFCL therapy group received treatment of UFCL at 3-month intervals, silicone sheets, and pressure garments, while another group only received treatment of silicone sheeting and compression. Twelve months after the termination of therapy, faciocervical scars of both two groups were assessed by two uninvolved physicians according to the Vancouver Scar Scale (VSS), and patients’ satisfaction survey was also recorded by the study participants using a patient four-point satisfaction scale. Thirty-six patients completed the treatment and follow-up. The results show that the VSS scores of both two groups decreased after 12 months, but comprehensive UFCL therapy group dropped more significantly than the conventional treatment group at follow-up session, which was statistically significant (P?<?0.001), and the patient satisfaction was higher than that of the conventional treatment group. This comprehensive treatment combined of surgery, UFCL, silicone sheets, and pressure garments works as an effective and esthetic reconstruction for moderate to severe postburn faciocervical scar contractures.

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108.
Germplasm cryopreservation and expansion of gonocytes/prospermatogonia or spermatogonial stem cells (SSCs) are important; however, it's difficult in cattle. Since inhibitors of Mek1/2 and Gsk3β (2i) can enhance pluripotency maintenance, effects of 2i-based medium on the cultivation of bovine prospermatogonia from the cryopreserved tissues were examined. The testicular tissues of newborn bulls were well cryopreserved. High mRNA levels of prospermatogonium/SSC markers (PLZF, GFRα-1) and pluripotency markers (Oct4/Pouf5, Sox2, Nanog) were detected and the PLZF+/GFRα-1+ prospermatogonia were consistently identified immunohistochemically in the seminiferous cords. Using differential plating and Percoll-based centrifugation, 41.59% prospermatogonia were enriched and they proliferated robustly in 2i medium. The 2i medium boosted mRNA abundances of Pouf5, Sox2, Nanog, GFRα-1, PLZF, anti-apoptosis gene Bcl2, LIF receptor gene LIFR and enhanced PLZF protein expression, but suppressed mRNA expressions of spermatogonial differentiation marker c-kit and pro-apoptotic gene Bax, in the cultured prospermatogonia. It also alleviated H2O2-induced apoptosis of the enriched cells and decreased histone H3 lysine (K9) trimethylation (H3K9me3) and its methylase Suv39h1/2 mRNA level in the cultured seminiferous cords. Overall, 2i medium improves the cultivation of bovine prospermatogonia isolated from the cryopreserved testes, by inhibiting Suv39h1/2-mediated H3K9me3 through Mek1/2 and Gsk3β signalling, evidencing successful cryopreservation and expansion of bovine germplasm.  相似文献   
109.
110.
BackgroundIn the first year of dialysis, patients are vulnerable to cardiovascular disease (CVD) hospitalization, but knowledge regarding the risk factors and long-term outcomes of cardiovascular readmission within the first year after dialysis in incident continuous ambulatory peritoneal dialysis (CAPD) patients is limited.MethodsThis retrospective cohort study was conducted in incident CAPD patients. The demographic characteristics, laboratory parameters, and CVD readmission were collected and analyzed. The primary outcome was all-cause mortality, and the secondary outcomes included CVD mortality, infection-related mortality and technique failure. A logistic regression was used to identify the risk factors associated with CVD readmission within the first year after dialysis. Cox proportional hazards models were used to evaluate the association between CVD readmission and the outcomes.ResultsIn total, 1589 peritoneal dialysis (PD) patients were included in this study, of whom 120 (7.6%) patients had at least one episode of CVD readmission within the first year after dialysis initiation. Advanced age, CVD history, and a lower level of serum albumin were independently associated with CVD readmission. CVD readmission within the first year after dialysis was significantly associated with all-cause (HR 2.66, 95%CI 1.91–3.70, p < 0.001) and CVD (HR 3.42, 95%CI 2.20–5.31, p < 0.001) mortality, but not infection-related mortality or technique failure, after adjusting for confounders.ConclusionsOur findings suggest that an advanced age, a history of CVD, and a lower level of serum albumin were independently associated with CVD readmission. Moreover, CVD readmission was associated with all-cause and cardiovascular mortality in incident CAPD patients.  相似文献   
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