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151.
Yoshinori Yamashita Toshihiro Hirai Hidenori Mukaida Takashi Iwata Tetsuya Toge Hong Jae Hoon 《Surgery today》1990,20(6):671-676
This report presents the effect of repeated heating every 24 hrs using bleomycin (BLM) which, although seemingly contrary
to the usual agreement that hyperthermia should be carried out with a long interval due to thermotolerance, holds many possibilities.
FM3A cells on the foot pad of C3H mouse were immersed in a heated water bath at 43 and 44°C for 30 min. The effect of repeated
heating was appreciated by an improved growth curve and 50 day survival compared to mice which received heating twice with
a 96-hr interval. Repeated heating every 24 hrs 5 times with BLM suppressed tumor growth significantly as compared to heating
twice with a 96-hr interval without BLM. The longest survival time was obtained by the repeated heating with BLM among all
protocols. There is therefore a good possibility that more effective results could be obtained clinically by repeated heating
over a short period. 相似文献
152.
N. J. GOODERHAM S. MURRAY A. M. LYNCH R. J. EDWARDS M. YADOLLAHI-FARSANI C. BRATT K. J. RICH K. ZHAO B. P. MURRAY S. BHADRESA S. J. CROSBIE A. R. BOOBIS & D. S. DAVIES 《British journal of clinical pharmacology》1996,42(1):91-98
1 Heterocyclic amines are formed in parts per billion levels when meat is cooked.
2 The heterocyclic amines MeIQx and PhIP are efficiently absorbed into the systemic circulation after ingestion of cooked food.
3 We have shown that MeIQx and PhIP, both in vitro and in vivo , are substrates for human hepatic CYP1A2, which exclusively and efficiently catalyses their conversion to genotoxic hydroxylamines.
4 MeIQx and PhIP are promutagens. MeIQx is a very powerful bacterial mutagen whereas PhIP is a more potent mammalian cell mutagen. Using a mammalian cell target gene, hprt , we have shown that PhIP induces a characteristic mutational 'fingerprint'.
5 MeIQx and PhIP are carcinogenic in bioassays. The PhIP mutational 'fingerprint' has been detected in the Apc gene of 5/8 colonic tumours induced by PhIP in rats. 相似文献
2 The heterocyclic amines MeIQx and PhIP are efficiently absorbed into the systemic circulation after ingestion of cooked food.
3 We have shown that MeIQx and PhIP, both in vitro and in vivo , are substrates for human hepatic CYP1A2, which exclusively and efficiently catalyses their conversion to genotoxic hydroxylamines.
4 MeIQx and PhIP are promutagens. MeIQx is a very powerful bacterial mutagen whereas PhIP is a more potent mammalian cell mutagen. Using a mammalian cell target gene, hprt , we have shown that PhIP induces a characteristic mutational 'fingerprint'.
5 MeIQx and PhIP are carcinogenic in bioassays. The PhIP mutational 'fingerprint' has been detected in the Apc gene of 5/8 colonic tumours induced by PhIP in rats. 相似文献
153.
章京 《第二军医大学学报》1988,(2)
实验观察了“安全”减压和不适当减压条件下家兔减压病(DCS)的发病情况、Doppler超声以及血浆中TxB_2和6-keto-PGF_(1a)的变化;还观察了消炎痛对DCS的预防怍用。结果显示:减压愈不当,DCS发病愈重,Doppler超声气泡探测仪检测到的级别愈高。血浆TxB_2、6-keto-PGF_(1α)值在濒死动物中明显升高(P<0.01);存活动物中,TxB_2经历了下降、再恢复的过程(P<0.01),而6-keto-PGF_(1α)值未见明显变化。消炎痛在抑制血浆TxB_2升高的同时,有效地降低了DCS发病率。此结果表明:TxA_2、PGI_2参与了重型DCS的发病过程,消炎痛的顶防作用与抑制花生四烯酸代谢物的生成有关。 相似文献
154.
本文研究指出,Line10肝癌腹水上清具有一定的免疫抑制作用,可致巨噬细胞形态改变并降低其吞噬功能,还可使BALB/c小鼠的白细胞数量下降。应用Ouchterlony法证明Line10肝癌腹水上清中存在line10肝癌细胞的抗原成分。 相似文献
155.
白细胞介素-10诱导的大鼠树突状细胞体外免疫功能的研究 总被引:19,自引:7,他引:12
目的 研究白细胞介素 10 (IL 10 )诱导的大鼠未成熟树突状细胞 (imDCs)体外诱导免疫耐受的可行性。方法 在经典诱导方案的基础上 ,应用IL 10 ( 10 μg/L)抑制大鼠骨髓来源DCs的成熟 (IL 10组 ,10例 ) ,并设对照组 (IL 4组 ,10例 )。培养期间观察DCs形态 ,检测DCs表型、摄取抗原能力、体外免疫功能及培养上清细胞因子水平。结果 与IL 4组比较 ,IL 10组DCs细胞表面CD80 、CD86及OX6低度表达 ( 2 5 .3 %、42 .4%、3 2 .3 % ) ,吞噬能力较强 ( 81.9) ,刺激同种异体淋巴细胞增殖能力下降 ,该淋巴细胞具有抗原特异性低反应性 ;培养上清中IL 12水平 ( 4 0 6.5pg/L)及初次MLR培养上清IL 2水平 ( 2 45 .4ng/L)均较低 ,差异有非常显著性 (P <0 .0 1)。 结论 IL 10作用的大鼠imDCs具有诱导免疫耐受的应用价值。 相似文献
156.
A seroepidemiological study was carried out in a geographically well-defined area in rural Crete in order to determine the prevalence of A, B and C hepatitis markers in the local population. Serum samples were obtained from 257 subjects (94 males, 163 females), aged 15 years and over, who visited the primary health care services of the Spili Health Centre between July 1993 and March 1994, and from 164 subjects (83 males, 81 females) randomly selected from households in three neighbouring villages of the study area. In samples obtained from the Spili Health Centre, antibodies to hepatitis A virus (anti-HAV) were detected in 234/244 (95.9%) subjects, antibodies to hepatitis B virus core antigen (HBcAb) were detected in 63/257 (24.5%) subjects and antibodies to hepatitis C virus (anti-HCV) were detected in 28/257 (10.9%) subjects. The corresponding figures for those randomly selected from the villages were 135/154 (87.7%), 16/164 (9.8%) and 5/164 (3%) respectively. Hepatitis B surface antigen (HBsAg) was positive in three (1.2%) subjects from the first group, while none of those recruited from the villages were positive for HBsAg. Interestingly, hepatitis markers were closely associated with age. No subjects under the age of 15 years showed evidence of prior hepatitis A infection and approximately 20% of those between 15 and 44 years of age were also negative. By contrast, practically all subjects older than 44 years were anti-HAV positive. Similarly, the majority of all those who were anti-HCV positive were older subjects. Seroepidemiology of hepatitis in this well-defined population seems to be different from other parts of Greece, at least for hepatitis B and C viruses. There is a very low prevalence of HBsAg and a very high incidence of anti-HCV. Low exposure to HAV, as found in other parts of the country, was also found in the younger generation in this rural area of Crete. 相似文献
157.
人群归因危险度百分比 (populationattributableriskproportion ,PARP)是总体人群中某种疾病归因于某种因素的暴露所引起的发病 (死亡 )占全部发病 (死亡 )的百分比 ,反映该因素所引起的发病 (死亡 )占全部发病 (死亡 )的比重。通过PARP可了解各危险因素对人群中某疾病的发病所产生的影响 ,亦即消除某危险因素后 ,所产生的对预防该疾病的效果将占有多大比重。它能够为卫生政策的制订提供依据 ,有着重要的公共卫生的实际意义。目前常用的估计PARP的方法有两种 :一种是利用全国人群抽样调查获得的人群总暴露率来估计 ;另一种是利用某地区… 相似文献
158.
自发性高血压大鼠内皮素A型受体基因的表达 总被引:2,自引:0,他引:2
应用反转录-聚合酶链式反应(reversetranscription-polymerasechainreaction,RT-PCR)方法,测定大鼠ET-A型受体(endothelinAreceptorETA-R)mRNA在体内的分布,证明ETA-RmRNA不仅存在于血管平滑肌细胞,亦存在于内皮细胞中;而且广泛分布于脑、心、肾、肺等组织内。首次发现,在SHR大鼠的脑、心、肾组织中,ETA-RmRNA水平明显升高,提示ETA-R基因表达增加,亦可能是高血压发病的一个重要因素。 相似文献
159.
Alcohol and Platelet Function 总被引:3,自引:0,他引:3
Epidemiological studies have shown that moderate consumption of alcoholic beverages is inversely related to the incidence of the complications of coronary artery disease. The protective effect of ethanol may be partially attributable to an inhibitory effect of ethanol on platelets. This article summarizes the experimental observations that ethanol inhibits platelet responses to specific physiological agonists. In alcoholics, various platelet defects have been observed, but these may be influenced by metabolic factors rather than the presence of ethanol alone. The acute effects of ethanol on platelet functions both in vivo and ex vivo will be reviewed. Evidence will be presented demonstrating that ethanol added acutely in vitro inhibits phospholipase A2 in stimulated platelets. The interaction of ethanol with other signal transduction pathways will also be discussed. 相似文献
160.
本文采用俯卧拍背法缓解胆绞痛41例,其中23例经此法治疗后疼痛立即消失(56.1%);15例明显缓解(36.6%);3例缓解不明显(7.3%)。具有操作简便、安全,易被患者接受,值得推广。 相似文献