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91.
目的探讨SNHG6对急性心肌梗死(AMI)小鼠左心室心肌的影响。 方法将30只雄性C57/BL6小鼠构建成AMI小鼠后随机均分为AMI组、AMI+SNHG6组、AMI+miR-101-3p组、AMI+SNHG6+miR-101-3p组、AMI+miR-101-3p+TGFBR1组,另设正常小鼠6只为假手术组。qRT-PCR检测AMI小鼠SNHG6、miR-101-3p表达水平。心脏彩超检测各组小鼠左室射血分数(LVEF);马松和天狼星红染色法以及免疫组化分析各组小鼠左心室心肌纤维化变化。将H9C2细胞株分为阴性对照组(转染空质粒)、SNHG6组(转染质粒SNHG6)、miR-101-3p组(转染质粒miR-101-3p)。Western blotting检测各组TGFBR1蛋白表达;采用双荧光素酶报告基因法预测并验证SNHG6/miR-101-3p/TGFBR1荧光素酶活性及调控机制。 结果AMI小鼠较假手术组SNHG6表达显著增加,miR-101-3p降低(P<0.05)。与AMI组比较,AMI+SNHG6组小鼠LVEF降低,心肌纤维化程度加重(P<0.05);AMI+miR-101-3p组LVEF升高,心肌纤维化程度减轻(P<0.05)。AMI+SNHG6+miR-101-3p组较AMI+SNHG6组LVEF升高、心肌纤维化程度减轻(P<0.05),而AMI+miR-101-3p+TGFBR1组较AMI+miR-101-3p组LVEF降低、心肌纤维化程度加重(P<0.05)。双荧光素酶报告基因法验证显示,miR-101-3p组SNHG6、TGFBR1野生型质粒的荧光素酶活性较阴性对照组明显降低(P<0.05)。 结论SNHG6抑制miR-101-3p上调TGFBR1加重AMI小鼠左心室心肌纤维化。  相似文献   
92.
Summary We studied senile plaques (SP) in the cerebella of six autopsied subjects with Alzheimer-type dementia (ATD) and ten non-ATD autopsied subjects between the ages of 78 and 90. Neither SP nor amyloid angiopathy (AA) was observed in any of the non-ATD subjects. In the four of the six ATD subjects, diffuse plaques in the molecular layer were seen as ill-defined areas of fine fibrillar materials by protein immunostaining with formic acid pretreatment, the modified Bielschowsky stain, and periodic acid-methenamine silver (PAM) stain. The plaques were not visible with Bodian, Congo red, or periodic acid-Schiff stains. Compact plaques in the Purkinje cell or in the granular cell layers were found in three of the six subjects. Their amyloid core was often surrounded by areolar amyloid deposits. AA was observed in three of the six subjects. The argyrophilia of the diffuse and compact plaques, demonstrated by the modified Bielschowsky and PAM stains, became undetectable when the sections were first treated with formic acid. Such treatment made the plaques immunoreactive with protein antiserum. The findings suggested that cerebellar diffuse plaques and compact plaques consist mainly of an amyloid component, and are characteristic of ATD.  相似文献   
93.
壬苯醇醚避孕药膜的临床研究   总被引:3,自引:3,他引:0  
894对健康、已育的育龄夫妇,随机分两组:447对使用壬苯醇醚方型膜,447对使用帽型膜,经两年连续观察。按生命表统计法处理数据。总使用妇女月,方型组9601,帽型组9382,随访率100%。累计停用率、妊娠率和续用率,方型组分别为16.8%、15.3%和83.2%,帽型组为18.4%、15.6%和81.6%,两组无显著差异(p>0.05)。临床和实验室资料表明壬苯醇醚药膜是安全、有效、简便、易于推广的避孕药具之一。  相似文献   
94.
We previously reported that c-kit+ stem cells which give rise to extrathymic T cells are present in the liver of adult mice. Further characterization of extrathymic T cells in the liver of adult mice is conducted here. When mice with a liver shield were lethally (9.5 Gy) irradiated, all mice survived. All tested organs showed a distribution pattern of hepatic lymphocytes on day 7. The distribution pattern in the liver was characterized by an abundance of NK (CD3? IL-2Rβ+) and extrathymic T cells (CD3int IL-2Rβ+) before and after irradiation. To determine their function, post-irradiation allogeneic bone marrow transplantation (BMT) was performed in mice with or without a liver shield. Allogeneic BM cells were rejected in mice with a liver shield and specific activation of CD8+ CD3int IL-2Rβ+ cells was induced. At that time, potent cytotoxicity of liver mononuclear cells (MNC) against allogeneic thymocytes was induced. Both NK1.1+ and NK1.1? subsets of CD3int cells expanded in these mice. An in vivo elimination experiment of the subsets indicated that the NK1.1+ subset of CD3int cells (i.e. NK T cells) was much more associated with the rejection of allogeneic BM cells. However, even after the elimination of NK T cells, allogeneic BM cells were rejected. In this case, granulocytes expanded in parallel with NK1.1? subsets. Granulocytes may also be associated with the rejection of allogeneic BM cells. These results suggest that the liver is an important haematopoietic organ even in adult life.  相似文献   
95.
Cannabinoids have been shown to influence food intake, and until recently, the neural pathways mediating these effects have remained obscure. It has been previously shown that intracerebroventricular injection of delta-9-tetrahydrocannabinol (Δ9-THC) causes increased consumption of palatable foods in rats, and we postulated the involvement of the hindbrain in this cannabinoid-induced food intake. Cannulated rats (both female and male groups) trained to consume sweetened condensed milk received either lateral or fourth ventricle injections of CP 55,940 and were presented with sweetened condensed milk 15 min after injection. Rats were injected over a range of doses between 100 pg and 10 μg per rat. Milk intake was recorded for a total of 3 h. Lateral ventricle injection of CP 55,940 increased milk intake at doses in the microgram range. However, CP 55,940 was effective in increasing food intake at nanogram doses when injected into the fourth ventricle. Finally, male rats appeared to be more sensitive to CP 55,940 than female rats inasmuch as milk consumption was increased at the 1 ng dose in male rats, whereas only the 10 ng dose was effective in females. These results indicate that CP 55,940 may act in the hindbrain to influence feeding behavior in rats.  相似文献   
96.
Since 1995, an injectable bone substitute is developed in our laboratory, it is based on a mix of an hydrogel (hydroxypropyl methylcellulose at 3%: cellulose ether) and biphasic calcium phosphate granules (MBCP® : 60% hydroxyapatite, 40% β-tri calcium phosphate). This first generation of injectable bone substitute is a non-self-hardening past, nevertheless it owns a great osteoconductor potential. But it shows a tendency to the discharge by its initial composition, and involved limited clinical applications. An evolution of this product is presented in this article: the modification is generated by a new self-hardening hydrogel. This hydrogel is a cellulose ether grafted by silane and diluted in an aqueous solution at basic pH. Also it will be presented the general synthesis of this cellulose derivate, the dissolution condition and the self hardening principle in function of the pH and the temperature. As to conclude by preliminary tests, the biocompatibility in vivo and in vitro of the self-hardening hydrogel mixed with biphasic calcium phosphate granules will be studied.  相似文献   
97.
Summary Derepression of lysine biosynthetic enzymes of Saccharomyces cerevisiae was investigated in lys9 auxotrophs which lack saccharopine reductase activity. Five enzymes (homocitrate synthase, homoisocitrate dehydrogenase, -aminoadipate aminotransferase, -aminoadipate reductase and saccharopine dehydrogenase) were constitutively derepressed in all lys9 mutants with up to eight-fold higher enzyme levels than in isogenic wild-type cells. Levels of these enzymes in lys2, lys14, and lys15 S mutants were the same or lower than those in wild-type cells. The regulatory property of lys9 mutants exhibited recessiveness to the wild-type gene in heterozygous diploids. Unlike the mating type effect, homozygous diploids resulting from crosses between lys9 auxotrophs exhibited even higher levels of derepressed enzymes than the haploid mutants. Addition of a higher concentration of lysine to the growth medium resulted in reduction of enzyme levels although they were still derepressed. These results suggest that lys9 mutants represent a lesion for the saccharopine reductase and may represent a repressor mutation which in the wild-type cells simultaneously represses unlinked structural genes that encode for five of the lysine biosynthetic enzymes.  相似文献   
98.
We have used fluorescent in situ hybridization and simultaneous in vivo bromodeoxyuridine labelling of a solid bladder cancer to examine tumour cell subsets for possible proliferative growth differences. In this dual-labelled preparation, most tumour cell nuclei exhibited monosomy 9, consistent with reported karyotypes of bladder cancer. Incorporated bromodeoxyuridine was visualized with a fluoresceinated antibody in 5-6 per cent of the tumour cells, concordant with S-phase estimates by cell cycle analysis of the flow cytometric DNA histogram. A majority of the bromodeoxyuridine-positive cells also carried the monosomy 9 chromosome abnormality. This is the first report to demonstrate the feasibility of combined in situ hybridization and detection of bromodeoxyuridine incorporated in vivo in human tumour cells in order to provide information on the growth rate of specific subsets of tumour cells identified by chromosomal constitution.  相似文献   
99.
胃癌患者血清CEA、CA19—9及CA72—4联检的临床价值探讨   总被引:2,自引:1,他引:2  
目的:探讨血清CEA、CA19—9及CA72—4联检在胃癌诊断、病情监测及疗效观察中的价值。方法:采用电化学发光技术检测36例正常对照组、42例良性胃病、55例胃癌患者血清CEA、CA19—9、CA72—4的含量,并对胃癌患者进行治疗前后三种肿瘤标志物的含量变化监测随防。结果:胃癌患者血清CEA、CA19—9、CA72—4的阳性率明显高于正常对照组及良性胃病组,差异有显著性(P〈0.01)。胃癌患者治疗后三种肿瘤标志物含量及阳性率较治疗前有明显下降,差异有显著性(P〈0.01)。三者联检的敏感性、准确性均显著提高(P〈0.01)。结论:血清CEA、CA19-9、CA72—4联检有助于提高胃癌诊断的敏感性、同时对疗效观察及术后监测有重要意义。  相似文献   
100.
Topical, intravaginal microbicides and spermicides are greatly needed to prevent transmission of sexually transmitted diseases and/or unwanted pregnancies. The development of such compounds is a high research priority. The presumed method of action of existing, or novel, microbicides/spermicides is to provide a chemical barrier to the vaginal epithelium preventing exposure to micro-organisms. Other intravaginal products are used to treat vaginal bacteria of fungal infections. Little is known, however, about the actual or optimal initial distribution and subsequent spread of medications placed in the vagina. We describe a sensitive new technique to quantify the spread of a gel placed in the vagina using magnetic resonance imaging (MRI). Five millilitres of an over-the-counter spermicide containing Nonoxynol-9 was mixed with Gadolinium. MRI was used to quantify spread of the mixture 10 min after insertion with a standard applicator. We demonstrated contiguous spread of gel throughout the vagina. The coverage of material was thicker in the upper vagina than in the lower vagina. We also demonstrated, for the first time, that spermicidal compounds may migrate from the vaginal canal into the endocervix within 10 min of insertion. This finding suggests that topical microbicides/spermicides may act both in the vaginal canal and in the upper female genital tract.  相似文献   
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