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目的 观察高渗盐水(7.5%NaCl溶液)、6%HES溶液(羟乙基淀粉溶液)对腹部手术后犬血清细胞因子分泌的影响.方法 18只麻醉犬全麻下行腹部手术后随机分成3组,输注不同液体并同时予以控制血压至基础值的60%(MAP65mmHg):4ml/kg 7.5%NaCl溶液(HS组);输注15ml/kg 6%HES溶液(HES组);C组(对照组)单纯降压组.在麻醉开始前(B),手术开始2小时(T1),液体输注完2小时(T2),术后第1天(T3),第2天(T4)抽取颈外静脉血3ml,检测血清中IL-2,IL-6,IL-8,IL-10,TNF-α的浓度.结果 对照组:各前炎因子TNF-α、IL-2、IL-6、IL-8随时间逐渐上升,至T3达到高峰,T4明显下降,但仍显著高于正常值(P<0.05).HS组和HES组TNF-α、IL-2、IL-6、IL-8在T3时均明显低于对照组,T4时由低到高依次为,HS组、HES组、对照组.HS组术后的IL-10水平升高,在T3达到最高值22.5 mmol/L,高于对照组(P<0.05).结论 HS溶液与6%HES溶液均可抑制腹部手术后犬致炎因子IL-2、IL-6、IL-8、TNF-α的升高.HS溶液还可使抗炎因子IL-10分泌增加,减轻术后的炎症反应. 相似文献
3.
目的利用基因工程技术制备铜绿假单胞菌外毒素A(PE),为深入研究PE的致病机理和免疫防治奠定基础。方法应用PCR技术从铜绿假单胞菌基因组中扩增外毒素A全长结构基因,将其克降于原核表达载体pQE-31中,所构建的重组质粒经测序鉴定后转化大肠埃希菌JM109, IPTG诱导表达;制备融合蛋白包涵体,并采用Ni-NTA柱亲和层析、葡聚糖凝胶过滤和阴离子交换层析分离和纯化目的蛋白;采用透析法对纯化后的目的蛋白进行复性,MTT法测定复性后的重组PE对L929细胞、B16黑素瘤细胞的细胞毒活性。结果通过对PCR反应体系的优化,扩增到了PE全长结构基因。所构建的pQE-PE重组质粒经酶切及测序鉴定与设计序列一致;转化E.coli JM109后,IPTG诱导目的蛋白表达率约为25%;SDS-PAGE初步测定目的蛋白的相对分子质量(M_r)约为66×10~3,与理论预期值一致;破菌后电泳证实目的蛋白主要以包涵体形式表达。经亲和层析、葡聚糖凝胶过滤和阴离子交换层析后蛋白纯度大于95%。MTT法测得重组PE对L929细胞和B16黑素瘤细胞的半数抑制浓度(IC_(50)值)分别为2.13μg/ml、2.58μg/ml。结论通过对PE的表达纯化,获得了具有细胞毒活性的重组PE,为利用基因工程手段大量制备PE的工作奠定了基础。 相似文献
4.
Excretion Profiles of the Mycotoxin Deoxynivalenol, following Oral and Intravenous Administration to Sheep 总被引:1,自引:0,他引:1
PRELUSKY DAN B.; VEIRA DOUGLAS M.; TRENHOLM H. LOCKSLEY; HARTIN KEN E. 《Toxicological sciences》1986,6(2):356-363
Excretion Profiles of the Mycotoxin Deoxynivalenol, followingOral and Intravenous Administration to Sheep. PRELUSKY, D. B.,VEIRA, D. M., TRENHOLM, H. L., AND HARTIN, K. E. (1986). Fundam.Appl. Toxicol. 6, 356363. The excretion profiles of deoxynivalenol(DON) and metabolites (DON glucuronide conjugate, 3,715-trihydroxytrichothec-9,12-diene-8-one(DOM-1), and DOM-1 glucuronide conjugate) were defined in malesheep following either intravenous (iv) or oral administrationof the toxin at levels of 0.5 and 5.0 mg DON/kg body wt, respectively.After iv dosing, urinary DON levels declined in a biphasic fashionwith an average elimination half-life (terminal phase) of 1.2hr. diminishing to baseline concentrations by 8 hr. Maximumurinary excretion rates for the two major metabolites identified(conjugated DON, conjugated DOM-1) occurred 0.51.5 hrafter dosing, exhibiting elimination half-lives of 2.2 and 3.1hr, respectively. Total recovery accounted for only about 66.5%of the dose: 63.0% in the urine (24.1% DON, 21.2% conjugatedDON, 0.5% DOM-1, 17.2% conjugated DOM-1) and 3.5% in bile (madeup almost completely of conjugated DOM-1). The peak biliaryexcretion rate for conjugated DOM-1 was found to occur within1 hr postdosing, which rapidly declined to baseline levels by5 hr. Following oral administration, urinary excretion ratesof the major metabolites (DON, conjugated DON, conjugated DOM-1)reached maximum 69 hr post-treatment, and declined exponentiallywith t values of 3.2, 4.0, and 5.0 hr, respectively. Urinaryand biliary recovery of administered DON averaged approximately7.1%: 7.0% in urine (2.1% DON, 3.6% conjugated DON, 0.06% DOM-1,1.2% conjugated DOM-1) and 0.11% in bile (predominately conjugatedDOM-1). Between 54 and 75% of the oral dose was recovered inthe feces. These findings indicate that DON and metabolitesdo not persist in the body following either a single oral orintravenous dose of DON and are rapidly excreted. However, followingiv administration, a portion of the dose (33.5%) remained unaccounted,presumably converted to unidentified metabolites. Based on theseresults it appears that metabolism is the major process of eliminationof DON in sheep. 相似文献
5.
贫血患者血清铁铁蛋白细胞内外铁检测结果分析 总被引:2,自引:0,他引:2
目的探讨各类贫血患者血清铁、铁蛋白和骨髓细胞内外铁含量多或寡与贫血症的相互关系.方法应用比色法、放射免疫法和普鲁士兰反应法检测186例各种贫血患者血清铁、铁蛋白浓度和细胞内外铁粒、铁小珠的含量.结果急、慢性白血病贫血、再生障碍性贫血、铁粒幼红细胞性贫血、溶血性贫血、巨幼红细胞性贫血患者血清铁浓度升高;肾性贫血、肝性贫血、缺铁性贫血、肿瘤性贫血、骨髓增生异常综合症(MDS-RA)患者血清铁下降;铁蛋白增高主要见于急、慢性白血病贫血和铁粒幼红细胞性贫血、肿瘤性贫血及骨髓增生异常综合症等;细胞内外铁颗粒减少和外铁消失主要见于缺铁性贫血和肾性贫血.结论检测血清铁、铁蛋白和细胞内外铁能灵敏地反映机体铁的贮存和利用水平;恶性肿瘤或其它细胞快速增殖时,细胞合成铁蛋白的能力较强. 相似文献
6.
目的:制备抗禽流感病毒(AIV)核蛋白(NP)的单克隆抗体(mAb)并进行特性鉴定。方法:分别用甲醛灭活的和TritonX-100裂解的AIV H9N2及AIVNP基因的原核表达产物免疫BALB/c小鼠。经细胞融合、间接ELISA筛选及克隆化,建立能稳定分泌抗AIV NP mAb的杂交瘤细胞株。mAb的效价采用间接ELISA测定,用交义反应试验及间接免疫荧光染色法检测mAb的特异性。结果:经细胞融合、筛选及克隆化,间接ELISA法测定,mAb共得到6株能稳定分泌抗禽流感病毒NPmAb的杂交瘤细胞株,分别命名为4F4、1C3、1G11、1C2、1D10及2E7。1G11、1D10腹水的ELISA效价最高,分别为2^-13和2^-14。交叉反应试验及间接免疫荧光染色检测表明,两株mAb的特异性良好。结论:其获得6株抗AIVNP的mAb,其中2株mAb1C11和1D10的效价最高,特异性良好,为AIV的研究及快速诊断方法的建立奠定了基础。 相似文献
7.
Eye lrritation caused by Formaldehyde as an Indoor AIr Pollution—A Controlled Human Exposure Experiment 总被引:3,自引:0,他引:3
YANG XU ZHANG Yun-ping CHEN DAN CHEN Wen-ge WANG RONG 《Biomedical and environmental sciences : BES》2001,14(3):229-236
Obejective The present study focuses on health assessment of wood based panels which are widely used in interior decoration practices over the recent years in China. Formaldehyde has been identified as chemical indicator of (IAO) and an indoor air pollutant. To test its health effects experiment was undertaken. Method A small environmental test chamber (60/L) was used as the generator of emission gas from new panels, and was operating at a temperature of 22.7±0.6℃ and a humidity of 44.4±2.5 % with an air exchange rate of 1.0±0.15h-1. On the three experimental days the values of product loading in chamber were 4, 2 and 6 m2/m3, respectively. Eight people were selected randomly from the students and employees of Wuhan Health and Anti-epidemic Station as subjects, with an average age of 21.9±5.9 years, and a gender ratio of 1:1, and two of them were smokers (one male and one female). The subjects' eyes were exposed to formaldehyde through a pair of goggles. Each goggle had its flow inlet and outlet, and connected to chamber exhaust of emission gas and to an exhaust from the room. The exposure time was very short, just 5 minutes and the formaldehyde doses were at 1.65±0.01, 2.99±0.07 and 4.31±0.02 ppm. A 60-mm linear visual analogue rating scales was used to measure the intensity of sensory eye irritation and a video tape recorder was used to record eye blinking frequency. Results The results demonstrated that tests of sensory eye irritation and eye blinking can be used for materials testing, and that a dose-effect as well as a time-variance of the effect can be measured. Conclusion The tests showed that eye irritation was perceived at all of the three levels. 相似文献
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9.
MUNGAS DAN; EHLERS CINDY L.; WALL TAMARA L. 《Alcohol and alcoholism (Oxford, Oxfordshire)》1994,29(2):163-169
The effects of alcohol and placebo on cognitive functioningin male, Asian-American college students were evaluated witha double-blind, placebo-controlled cross-over design using amulti-trial learning test in which verbal and spatial learningwere simultaneously assessed. Verbal recall was impaired consistentlyacross learning trials, while impairment of spatial recall wasevident only on later learning trials. Recall of spatial informationwas influenced by order of presentation and amount of exposuretime of items. Results do not support a theory that spatiallearning is more impaired by alcohol than verbal learning, andthus do not lend support for the hypothesis that alcohol hasa greater effect on right than left hemisphere functioning.Results provide evidence that alcohol increases susceptibilityto interference effects. 相似文献