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41.
目的 建立胶束HPLC测定动物肌肉中三聚氰胺残留量的分析方法。方法 样品在酸性条件下,用乙
腈-磷酸盐缓冲液提取。以胶束溶液作为流动相,用HPLC测定,外标法定量。结果
线性范围为(0.1~10.0)mg/L,相关系数为0.9996。动物肌肉在(0.5~5.0)mg/kg添加水平范围内,回收
率在80%~110%。相对标准偏差〈10%。方法的最低检出限0.5mg/kg。结论该法实用、准确,为动物肌肉中
三聚氰胺残留量检测提供了可行的方法。 相似文献
42.
Vaccination, when available, is undoubtedly the most cost-effective means of preventing and controlling, and even eradicating, infectious diseases. In recent years vaccination has also been used for other purposes in animal health, production and welfare, e.g. immunocastration.Vaccination of animals serves many different purposes, such as controlling animal infections and infestations, thus improving animal health and welfare; controlling anthropozoonoses and food poisoning in humans, thereby protecting public health; solving problems associated with antibiotic and anthelmintic resistance; helping to leave food-producing animals free of chemical residues; protecting the environment and biodiversity and ensuring animal farming sustainability. The problem is nevertheless more complex when facing emerging or re-emerging infections particularly zoonotic ones. 相似文献
43.
重症胰腺炎动物模型制作及发病机理的研究 总被引:6,自引:1,他引:5
为探讨胰腺炎的发病机理,作者采用大鼠(n=58只)十二指肠结扎法和犬(n=46条)胰管内注射自身胆汁法制作重症胰腺炎的动物模型。该模型接近人类急性胰腺炎的发病因素,方法可靠,操作简便,费用便宜。前者适用于小动物实验,后者宜于大动物实验。作者认为胰管内压力增高和微生物是急性胰腺炎的重要条件;胰酶激活始动时间早在胰管内胆汁和肠液的反流后,胰酶激活的主要部位在腺泡细胞。 相似文献
44.
枸杞多糖对高温损伤小鼠睾丸曲细精管影响的电镜观察 总被引:2,自引:0,他引:2
为研究枸杞多糖对小鼠睾丸生细红胞的作用,本次以热吹风器对小鼠双侧睾丸透热(B组),另取正常不透热小鼠为空白对照(A组),蒸馏水灌胃对照(C组)和透热后灌鼠枸杞多糖(D组),进行实验观察,待B、C、D各组于透热结束后即刻、3天、1周、2周,5周处死动物,取双侧睾丸,常规作光镜和电镜观察。实验结果表明,B组各期生精细胞进行性受损,属肿胀溶解性细胞变性坏死过程,D组则在1周时受损部位和程度未见进行性加重,5周对基本恢复正常,提示枸杞多糖有明显的抗高温,保护生精细胞作用。 相似文献
45.
Flow Cytometric Analysis of Lymphocyte Subsets of Mice Maintained on an Ethanol-Containing Liquid Diet 总被引:1,自引:0,他引:1
Linda Hsiung Joseph Wang Carl Waltenbaugh 《Alcoholism, clinical and experimental research》1994,18(1):12-20
Alcoholic patients often have impaired immune function, yet little is known about the precise mechanism(s) of this impairment. We have previously shown that ethanol consumption by mice alters copolymer-specific humoral and cellular immune responses. In this study, we asked whether alcohol consumption by mice would phenotypically alter lymphocyte populations. Female C57BL/6 mice were fed a nutritionally complete liquid diet containing 35% ethanol-derived calories for up to 8 days. As controls, mice either were fed a liquid control diet that isocalorically substitutes sucrose for ethanol or remained on a standard solid diet and water ad libitum. Although mice fed ethanol-containing liquid or pair-fed control liquid diets have decreased numbers of spleen cells compared with solid diet controls, only the ethanol-containing diet allowed normally nonresponder C57BL/6 spleen cells to make antibody responses to the poly(Glu50Tyr50) synthetic copolymer antigen. Flow cytometric analysis of splenic lymphocyte populations of mice on the ethanol-containing diet shows an increase in the relative proportion of T-lymphocytes as compared with mice on either solid or liquid control diets. No such change is seen for either B-cell or natural killer cell populations in these same mice. Both liquid control and liquid ethanol diets caused a slight decrease in the CD4:CD8 ratios of splenic T-lymphocytes. We see the relative percentage of T-cells bearing the αβ-cell receptor (TcR) increases in the spleens of liquid ethanol diet mice; a smaller increase TcRαβ usage is seen in the spleens of liquid control mice, compared with solid diet mice. Flow cytometric analysis shows that little, if any, difference exists in TcRγδ expression between the liquid ethanol and either the liquid control or solid diet groups. Preliminary analysis of TcRαβ subsets suggest that ethanol increases the percentage of T-cells expressing Vβ5 and Vβ8, and decreases the percentage of Vβ11 expressing cells. These findings suggest that, in addition to modifying the immune response, ethanol alters the phenotypic expression of lymphocyte subsets. 相似文献
46.
复方红芪减方对周围神经再生影响的实验研究 总被引:4,自引:2,他引:2
目的 研究复方红芪提取液进行减方后对周围神经再生的作用。方法 建立钳夹损伤大鼠双侧坐骨神经的动物模型。按术后每日灌服药物的不同将 40只SD雄性大鼠随机均分为 4组。对照组 :灌服生理盐水 ;复方红芪组 :灌服复方红芪提取液 2ml ;减方组 :灌服复方红芪减方后提取液 2ml;补阳还五汤组 :灌服补阳还五汤 2ml。术后 2周及 4周 ,观察坐骨神经功能指数、运动神经传导速度及单位视野有髓神经纤维计数。结果 坐骨神经功能指数 :红芪组和减方组与对照组、红芪组与减方组的差异均有显著意义 (P >0 .0 5 ) ,且减方组优于红芪组 (P >0 .0 5 )。有髓神经纤维计数 :复方红芪组优于对照组 (P<0 0 1) ,减方组明显优于对照组 (P <0 .0 1) ,而红芪组与减方组间无显著差异。运动神经传导速度 :红芪组、减方组、补阳还五汤组与对照组相比 ,均优于对照组 (P <0 .0 5 ) ,但前 3组间无明显差异。结论 复方红芪减方提取液早期可以促进周围神经再生 ,药效更为专一 ,且优于传统方剂补阳还五汤。 相似文献
47.
48.
爱母分娩工程初探——产程系列服务模式 总被引:1,自引:0,他引:1
爱母分娩工程的核心是产时分娩的管理,除医疗技术水平为重要因素外,改善产科系列服务模式,加强孕妇夫妇有关培训与健康教育,加强保健与临床的结合,对爱母分娩工程的作用亦是举足轻重的。广东省妇幼保健院试运行产时分娩管理新模式、产科系列服务新模式,提高了产科质量和社会效益及经济效益。 相似文献
49.
We have established a rat model that reflects the course of development of alcohol and opiate addiction. The present study
with d-amphetamine aimed to define general principles in the development of an addiction. Male rats had a continuous free choice
between d-amphetamine solutions (100, 200 and 400 mg/l) and water for 47 weeks. An initial intake of high doses of d-amphetamine during the first weeks of drug choice was followed by an individually stable pattern of drug consumption of moderate
drug doses. During this period of controlled consumption (from week 10 to week 40), the voluntary intake of d-amphetamine depended on individual factors (dominant rats: 0.37 ± 0.02 mg/kg per day, subordinate rats: 0.57 ± 0.05 mg/kg
per day) and environmental variables (group housing: 0.21 ± 0.02 mg/kg per day, single housing: 0.41 ± 0.03 mg/kg per day).
Beginning with week 41, voluntary d-amphetamine consumption progressively increased (1.9 ± 0.2 mg/kg per day in week 47), although the experimental conditions
remained unchanged. Drug intake during a retest (free choice as before) after 6 months of drug deprivation revealed that the
rats had persistently lost their control over drug intake and were no longer able to adjust drug taking to internal and external
conditions. These addicted rats took very high drug doses, even when all d-amphetamine solutions but not water were adulterated with bitter tasting quinine (6.6 ± 0.6 mg/kg per day; age-matched controls:
0.37 ± 0.04 mg/kg per day). Forced intake of d-amphetamine for 47 weeks (7.1 ± 0.3 mg/kg per day) via the drinking fluid caused physical dependence (hyperreactivity during
withdrawal) but did not lead to drug addiction (voluntary intake in the retest with adulteration: 0.42 ± 0.04 mg/kg per day).
Both the temporal development and the prerequisites of psychostimulant addiction were in principle the same as for alcohol
and opiates.
Received: 3 April 1998/Final version: 26 August 1998 相似文献
50.
Effects of antipsychotic drugs on latent inhibition: sensitivity and specificity of an animal behavioral model of clinical drug action 总被引:1,自引:1,他引:0
Latent inhibition (LI) of a conditioned emotional response (CER) has been proposed as a quantitative measure of selective attention. We have assessed the parallels of the pharmacology of LI in rats with the clinical pharmacology of schizophrenia. Drug and vehicle treated rats were divided into groups and preexposed 20 times to cage illumination as a CS, or not preexposed. All groups were conditioned with 2 CS-footshock pairings. The following day CER, as measured by interruption of drinking in response to CS presentation, was recorded. LI was observed as a decreased CER in preexposed relative to non-preexposed animals. LI was enhanced by haloperidol 0.3 mg/kg after 7 or 14 daily treatments, but not after a single acute dose. Haloperidol doses of 0.3 and 0.03 mg/kg enhanced LI, while doses of 0.003 and 3.0 mg/kg had no effect. Haloperidol enhancement of LI was unaffected by the coadministration of the anticholinergic agent trihexyphenidyl. Enhancement of LI is exhibited by the antipsychotic drugs fluphenazine, chlorpromazine, thiothixene, thioridazine, mesoridazine, and metoclopramide but not clozapine. The non-antipsychotic drugs pentobarbital, imipramine, chlordiazepoxide, trihexyphenidyl, and promethazine failed to enhance LI. LI exhibits striking parallels to the clinical pharmacology of schizophrenia.Preliminary data were presented in part at the Society for Neuroscience Annual Meeting, Phoenix, AZ, 1989 相似文献