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131.
Selective markers of bone turnover provide a convenient and reproducible alternative to the complex and expensive histochemical
techniques used commonly to study the effect of pharmacological agents and the pathogenesis of bone disease in the ovariectomized
(OVX) rat model. One marker, which has been specifically linked to terminally differentiated osteoclasts and, thus, provides
useful insight at cellular levels, is type-5 tartrate-resistant acid phosphatase (TRACP). We describe the development of a
TRACP radioimmunoassay (RIA), which requires synthetic peptide for antibody development. To develop the RIA, polyclonal antibodies
were generated in goats against a synthetic peptide, DPSVRHQRKCY, corresponding to amino acid residues 267–275 of the rat
type-5 TRACP sequence. In the RIA, 50 μl of rat serum, 100 μl of goat anti-TRACP antibodies, and 100 μl of tracer were incubated
overnight. The antibody-bound fraction was separated, counted, and unknown values were calculated by comparison with the peptide
calibrator. Rat serum shows parallelism with the synthetic peptide calibrator used in the RIA. The sensitivity of the RIA
was 24.7 μg/l, and the measuring range was 19–2476 μg/l. The average intra-assay coefficients of variation for (CV) two controls
were less than 7%. The average dilution and spike recoveries were 107% and 87%, respectively. We applied our peptide-based
RIA to study bone resorption in an OVX rat model. TRACP concentrations in serum in 12-week-old OVX Sprague Dawley rats were
14%–22% (P < 0.05) higher than those in the sham-operated rats, and TRACP concentrations in OVX rats treated with estradiol were 24%–32%
lower (P < 0.01) than those in the vehicle-treated OVX group. Similarly, as compared with those in OVX rats, TRACP concentrations
decreased to those of sham levels in OVX rats receiving 10 μg/kg per day of alendronate for 10 days. In addition, the TRACP
levels determined by RIA showed a significant correlation with serum C-telopeptide (type-I collagen) concentrations (r = 0.56; P < 0.001) measured by an enzyme-linked immunosorbent assay (ELISA) developed earlier for the rat model. In conclusion, we
have developed a TRACP RIA that could be used to monitor the rate of bone resorption in the rat model.
Received: June 18, 2001 / Accepted: October 26, 2001 相似文献
132.
Treatment of rats with clofibrate markedly stimulated the liver microsomal esterification of estradiol, testosterone, pregnenolone, dehydroepiandrosterone, and corticosterone by acyl-CoA:steroid acyltransferase. This enzyme catalyzes the esterification of estradiol with long-chain fatty acids in both liver and extrahepatic tissues. In untreated control rats, brain had the highest acyltransferase activity per milligram of microsomal protein for estradiol esterification (3- to 4-fold higher than in the liver). Although, treatment of rats with clofibrate stimulated the esterification of estradiol by 9- to 14-fold in the liver, estradiol esterification in kidney, lung, brain, uterus, fat, and mammary glands was not increased, indicating that liver may be uniquely sensitive to induction of acyl-CoA:estradiol acyltransferase by clofibrate. In additional studies, esterase activity for hydrolysis of the oleoyl ester of estradiol was determined in control and clofibrate-treated rats. Clofibrate administration increased esterase activity by an average of 107% in fat and 70% in liver. The results indicate that treatment of rats with clofibrate stimulates the hepatic formation of highly lipophilic fatty acid esters that can be hydrolyzed in the liver and in extrahepatic tissues to the parent steroid hormone by a clofibrate-inducible esterase. 相似文献
133.
Endrikat J Klipping C Cronin M Gerlinger C Ruebig A Schmidt W Düsterberg B 《Contraception》2002,65(3):215-221
In this open label, randomized study we compared the influence of a dose-reduced oral contraceptive containing 20 microg ethinyl estradiol (EE) and 100 microg levonorgestrel (20 EE) with a reference preparation containing 30 microg EE and 150 microg levonorgestrel (30 EE) on hemostatic, lipids, and carbohydrate metabolism variables. Data from 48 volunteers were obtained. The direction of the change (increase or decrease) in most of the hemostatic variables were similar in both treatment groups. In particular, prothrombin fragment 1 + 2 increased during treatment, reaching a median percent change of 40% in the 20 EE group and of 17% in the 30 EE group after one year. D-Dimer fibrin split products remained virtually unchanged, with no change at Cycle 13. The median HDL2 cholesterol levels decreased by 26% in the 20 EE group and by 39.8% in 30 EE group (p = 0.0045 for group difference) after one year. The median one year change for LDL cholesterol was 3.23% in the 20 EE group, compared to 25% in the 30 EE group, for VLDL 11.1% compared to 38.8%, respectively, and for total triglycerides 10.0% compared to 37.5%, respectively. The median absolute change for the area under the curve (AUC)(0-3h) for glucose at treatment Cycle 13 was 41.25 mmol/L x min in the 20 EE group and 73.50 mmol/L x min in the 30 EE group. The AUC(0-3h) insulin at treatment Cycle 13 decreased in the 20 EE group by 1635.0 pmolL x min and increased in the 30 EE group by 11797.5 pmolL x min (p = 0.0491 for group difference). Both study treatments were safe and well tolerated by the volunteers.In conclusion, the balanced one-third dose reduction in this new oral contraceptive evoked similar effects on the hemostatic variables, but favorable results for the lipid and carbohydrate profiles. 相似文献
134.
目的: 探讨雌激素在整体水平下的抗肾上腺素心律失常作用及可能机制.方法:24只新西兰大白兔随机分为对照组、利多卡因组及雌激素组,各组同步记录体表心电图及经左心室插管测定心功能指标[ 左心室内压(LVSP)、左心室舒张终末压(LVEDP)、左心室内压最大上升速率(+dp/dtmax)、左心室内压最大下降速率(-dp/dtmax) ], 比较各组按75 μg/kg 静脉注射0.1%肾上腺素前后心电图及相应心功能指标变化.结果:快速静脉注射肾上腺素可引起心功能指标明显上升,同时由于自律性增高致室性心律失常;雌激素可拮抗肾上腺素所致心功能改变,并延长室早(VP)出现时间,缩短室速(VT)持续时间及心律失常持续时间,其作用优于利多卡因(P〈0.05).结论: 雌激素对心律失常有一定对抗作用,可能与Ca^2+阻断及改变细胞膜离子通透性有关. 相似文献
135.
This paper assesses the basic steps of management and treatment of dysfunctional uterine bleeding (DUB) - the irregular bleeding arising from anovulation. After menarche, the hypothalamic-pituitary-ovarian axis can take several years to mature resulting in anovulatory and therefore irregular cycles. During an anovulatory cycle, the corpus luteum fails to form, causing failure of normal cyclical progesterone secretion. This results in continuous unopposed production of estradiol, stimulating overgrowth of the endometrium. Without progesterone, the endometrium grows thicker and thicker eventually outgrowing its blood supply, leading to necrosis. The end result is very heavy bleeding. 相似文献
136.
单纯性肥胖男生血清瘦素、性激素水平及性发育调查 总被引:4,自引:0,他引:4
目的:研究男性血清瘦素水平与单纯性肥胖、青春期性发育的关系。方法: 49名 8~16岁单纯性肥胖男生和 44名正常男生按年龄划分为 8~岁、11~岁和 14~16岁 3个年龄段,采用放射免疫法对各组男生进行血清瘦素、睾酮、雌二醇含量定量测定,同时进行首次遗精时间调查。结果:肥胖组各年龄段血清瘦素水平均高于正常组(P<0. 05或 0. 01);随着年龄增长,肥胖组男生血清瘦素水平呈现先上升后下降的变化趋势,在 11~岁年龄段达最高值;而正常组男生血清瘦素水平随着年龄增长则呈现下降的趋势。肥胖组男生首次遗精时间 (12. 5±1. 2)岁,早于正常组男生(13. 2±1. 2)岁(P<0. 01)。雌二醇水平在 11~岁年龄段,肥胖组低于正常组(P<0. 05)。睾酮水平各年龄段,肥胖组与正常组比较,差异均无统计学意义(P>0. 05)。肥胖组男生睾酮与瘦素呈负相关 (r=-0. 33,P<0. 05)。结论:单纯性肥胖男生血清瘦素水平偏高;持续高浓度的瘦素水平可能对男性性发育产生一定的负面影响。 相似文献
137.
138.
目的:探讨系统性红斑狼疮(SLE)外周血单个核细胞(PBMC)经雌二醇(E2)刺激前后TNFα和IL-6水平变化的相关性。方法:提取SLE患者(患者组)及健康志愿者(对照组)的PBMC,用酶联免疫吸附法(ELISA)测定上清液在E2刺激前后的肿瘤坏死因子α(TNFα)和白细胞介素6(IL-6)水平。结果:患者组有或无E2刺激的PBMC分泌的TNFα水平均高于对照组(P〈0.01),患者组E2刺激后PBMC分泌的TNFα水平低于无E2刺激时(P〈0.05),而对照组E2刺激前后TNFα水平无明显变化(P〉0.05)。无E2刺激的PBMC分泌的IL-6水平患者组高于对照组(P〈0.05),患者组有E2刺激PBMC分泌的IL-6水平与对照组比较差别无统计学意义(P〉0.05)。2组PBMC在E2刺激后分泌的IL-6水平均降低(均P〈0.05)。结论:TNFα和IL-6水平可以作为SLE疾病活动的监测指标,高水平的E2对SLE的PBMC分泌TNFα和IL-6都有明显抑制作用。TNFα的降低可能提示为SLE活动期。 相似文献
139.
XW630对去卵巢大鼠骨质疏松的作用(英文) 总被引:2,自引:0,他引:2
目的:研究XW630对去卵巢大鼠骨质疏松的影响。方法:血清E_2和骨钙素(BGP)浓度用放射免疫测定法。骨组织计量学用四环素内标法。结果:去卵巢后,血清E_2水平下降61.9%,子宫减轻72.7%,动情次数减少63.6%。XW630治疗13周后,血清BGP浓度增加75.7%,动情次数略增加,但低于假手术组,血清E_2浓度及子宫重量无明显变化。与OVX组相比,XW630组骨组织计量学指标TBV/TTV,TBV/SBV和MTPD增加;Sfract(s),Sfract(d),TOS和Svf增加,OMP缩短。结论:XW630增加骨激活频率、骨小梁连接性、稳定性和张力。表明XW630促进骨形成、抑制骨吸收,对生殖系统无影响。 相似文献
140.
针刺对小鼠实验性前列腺增生的防治作用 总被引:2,自引:1,他引:1
目的:探讨针刺治疗前列腺增生症的作用机理。方法:采用丙酸睾丸素皮下注射造成小鼠前列腺增生模型,通过针刺白环俞、会阴旁、委阳和三阴交穴,观察针刺对前列腺湿重、组织形态、血清睾丸酮、雌二醇、酸性磷酸酶含量的影响。结果:针刺对丙酸睾丸素引起的小鼠前列腺增生有显著的抑制作用,可使增生的前列腺重量明显减轻,腺上皮细胞增生明显减少,并能降低血清睾丸酮含量,抑制酸性磷酸酶活性,升高雌二醇含量。结论:针刺治疗前列腺增生症的作用机理与降低血清睾丸酮含量,升高雌二醇含量,抑制酸性磷酸酶的活性有关。 相似文献