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941.
目的 观察低密度脂蛋白(LDL)免疫吸附疗法对高脂血症的治疗效果.方法73例高脂血症患者接受LDL免疫吸附治疗.比较1次治疗前后各项血脂指标的变化.部分病例1个月后复查血脂各项指标.总结LDL免疫吸附疗法的安全性和副作用.结果①所有患者经1次LDL免疫吸附后血甘油三脂、胆固醇和低密度脂蛋白均有明显下降(p<0.01).高密度脂蛋白略有下降(p>0.05).患者临床症状改善.②治疗后1个月复查,血脂各项指标恢复到治疗前水平(p>0.05).③3例药物治疗不能控制的乳糜微粒血症患者经LDL免疫吸附治疗后血脂明显下降,但仍达不到正常范围.其中1例治疗后继续服用原降脂药物,药物疗效较前提高.④30例患者治疗过程出现低血压.结论LDL免疫吸附能有效降低血甘油三脂、胆圃醇和低密度脂蛋白水平,对高密度蛋白无明显影响.1次治疗所能维持血脂于低水平的时间短暂.部分患者临床症状改善.低血压是主要并发症. 相似文献
942.
硝苯啶、硫氮(艹卓)酮对兔实验性动脉粥样硬化症的影响 总被引:1,自引:0,他引:1
硝苯啶和硫氮(艹桌)酮不明显影响血清脂蛋白组分水平,但均显著抑制家兔主动脉动脉粥样硬化形成,降低血浆过氧化脂质、血栓烷和主动脉内中膜胆固醇、磷脂及钙含量,升高血浆6-酮-PGF_(1α),使,TXB_2/6-酮-PGF_(1α)趋于平衡。说明钙在血栓烷-前列环素代谢中起重要作用。 相似文献
943.
本研究提出基于EEG序列模糊相似性指数方法预测癫痫发作.首先,结合复自相关法和Cao法对EEG序列进行了相空间重构;然后,计算相关积分时用Gaussian函数代替Heavyside函数,克服了Heavyside函数的刚性边界问题,使得计算相似性指数更加准确和可靠;最后,分析大鼠癫痫EEG信号,检测癫痫发作前期状态.分析结果表明模糊相似性指数方法能够比动态相似性指数方法获得更长的预测时间和更低的错误预测率. 相似文献
944.
Lam GK Liao HX Xue Y Alam SM Scearce RM Kaufman RE Sempowski GD Haynes BF 《Journal of clinical immunology》2005,25(1):41-49
CD7 is an immunoglobulin superfamily molecule expressed on T, NK, and pre-B lymphocytes. Previous studies have demonstrated a role for CD7 in T- and NK-cell activation and cytokine production. Recently, an epithelial cell secreted protein, K12, was identified as a CD7 ligand. Although CD7 is expressed intrathymically, it is not known if K12 is produced in human thymus. To determine roles that K12 might play in the human thymus, we analyzed expression of K12 in human thymocytes, thymic epithelial cells (TE), and thymic fibroblasts. We found that recombinant human K12 bound strongly to soluble hCD7, with a Keq of 37.6×10–9M, and this interaction was inhibited by a novel antihuman K12 monoclonal antibody (K12-A1). K12 mRNA was detected by RT–PCR and northern analysis in human TE and thymic fibroblasts, but not in human thymocytes. Expression of K12 in TE cells was upregulated by IFN- . Taken together, these data demonstrated that K12 is produced by human TE cells and thymic fibroblasts, and is regulated in thymus by IFN- . These data suggest a role for thymic microenvironment-produced K12 in regulation of thymocyte signaling and cytokine release, particularly in the setting of thymus pathology where IFN- is upregulated such as myasthenia gravis. 相似文献
945.
Mei Shuang Jing Liu Mei Xiang Jia Jian Zhong Yang Su Ping Wu Xiao Hong Gong Yan Su Ling Yan Ruan Xiao Ling Yang Dai Zhang 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2004,(1):48-50
The glutamate pathways are involved in diverse processes such as learning and memory, epilepsy, and they play important roles in neural plasticity, neural development, and neurodegeneration. It has been proposed that autism could be a hypoglutamatergic disorder. Recently, Jamain et al. reported that the glutamate receptor 6 (GluR6 or GRIK2) is in linkage disequilibrium with autism. In the present study, the transmission disequilibrium test (TDT) and the haplotype transmission were performed to analyze the four SNPs (SNP1: rs995640; SNP2: rs2227281; SNP3: rs2227283; SNP4: rs2235076) of GluR6 in 174 Chinese Han parent-offspring trios. The TDT demonstrated that the two SNPs (SNP2 and SNP3) showed preferential transmission (TDT P = 0.032). The global chi(2) test for haplotype transmission also revealed an association between GluR6 and autism (chi(2) = 10.78, df = 3, P = 0.013). Our results suggested that GluR6 is in linkage disequilibrium with autism. 相似文献
946.
Vaccinia virus is a member of the orthopoxvirus group, to which also belongs variola virus, one of the most hazardous pathogens known to man. To establish a model system to detect orthopoxviruses, a vaccinia oligonucleotide microarray is designed, produced and tested. Vaccinia virus is used to test the prepared microarrays. The virus DNA samples in different propagation phases are extracted and hybridised with the oligonucleotide microarray. The results showed that the oligonucleotide microarray can detect vaccinia virus with high specificity and sensitivity. 相似文献
947.
磷脂酶C-γ1在人胚胎脊髓中的表达变化 总被引:1,自引:0,他引:1
为了了解磷脂酶C-γ1(PLC-γ1)的发育表达变化特点,本研究采用免疫组织化学方法检测不同发育时期的人胚胎脊髓中PLC-γ1的表达及变化。结果显示:PLC-γ1在人胚胎脊髓3周到7个月的整个发育过程中均有表达,在发育早期阳性反应可见于神经管内、外界膜,随着套层、边缘层的形成,神经上皮层、套层中均可见到PLC-γ1阳性反应物,且翼板阳性细胞较基板密集;套层阳性细胞在8、9周时达到高峰,随后开始逐渐减少。3个月时边缘层出现散在的阳性细胞,并随着脊髓的发育而逐渐增多。以上结果提示,PLC-γ1及其与PLC-γ1相关的细胞信号通路对人胚胎脊髓的发育可能发挥了重要的生物学作用。 相似文献
948.
本文通过Percoll梯度离心法分离获得大鼠中性粒细胞(PMNS)后,采用PMNS与玻璃珠粘附的模型,通过给予Dex及糖皮质激素受体(GR)阻断剂Mifepristone(RU_(38486))研究大鼠PMNS粘附过程中GR的作用。结果显示,Dex可以明显抑制PMNS的粘附,其作用随着Dex浓度的增大而增强;单纯给予不同浓度的RU_(38486)未发现明显的PMNS粘附增强,说明RU_(38486)本身对离体的PMNS粘附没有明显的作用;若同时给予Dex和RU_(38486),则Dex抑制PMNS粘附的作用逐渐减小,直至完全逆转。该结果强烈提示:糖皮质激素(GC)具有抑制PMNS粘附的作用,其作用是通过GR介导的,当GR被阻断时,这一抑制作用减弱,甚至消失。 相似文献
949.
目的:研究长链非编码RNA HOTAIR调控糖皮质激素受体的表达对急性淋巴细胞白血病细胞增殖及凋亡的作用。方法:采用RT-qPCR法检测人正常骨髓基质细胞系HS-5及急性淋巴细胞白血病细胞系MOLT-4、CCRF-CEM和CEM-C1中HOTAIR和糖皮质激素受体的表达。用si RNA沉默CEM-C1细胞中HOTAIR的表达,CCK-8法检测si-HOTAIR对CEM-C1细胞活力的影响; Brd U法检测si-HOTAIR对CEM-C1细胞增殖的影响以及对地塞米松抑制CEM-C1细胞增殖的增效作用; Hoechst 33342染色法和caspase 3/7活性检测法研究si-HOTAIR对CEM-C1细胞凋亡的影响;并采用Western blot法检测糖皮质激素受体的蛋白表达水平。结果:人急性淋巴细胞白血病细胞系MOLT-4、CCRF-CEM和CEM-C1中HOTAIR的表达显著高于人正常骨髓基质HS-5细胞(P 0. 01)。在CEM-C1细胞中干扰HOTAIR表达后,细胞活力降低,细胞增殖被抑制并发生凋亡,地塞米松抑制CEM-C1增殖的作用被增强,糖皮质激素受体表达上调(P 0. 01)。结论:长链非编码RNA HOTAIR增强急性淋巴细胞白血病的活力,促进其增殖并抑制其凋亡,该作用可能与其抑制糖皮质激素受体的表达有关。 相似文献
950.
Yan J Zhang Y Roder J McDonald RJ 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,150(2):184-193
One reason the electrophysiological correlates of hippocampal neurons are of interest is the possibility that they reflect
their representational properties, presumably spatial/relational ones. Stable spatial representations, based on activity of
ensembles of hippocampal place cells, initially develop through a series of short-episodic spatial tunings. Hence these short-episodic
spatial tunings are important for understanding the establishment of stable place fields. Studies of age-related changes in
place cell activities traditionally focus on place fields. In the present study, we characterized the short-episodic spatial
tunings (1-min bins) of hippocampal CA1 place cells of freely moving mice in a familiar cylinder arena, and compared these
functions in young and old mice. Spatial tuning was expressed by spatial selectivity, which we found fluctuated across a 16-min
recording session in both young and old mice. High spatial selectivity, which is mainly due to the low firing of a place cell
out of the place field in young mice, was significantly higher in old mice. The high firing rate out of the place field was
the main factor contributing to significantly lower spatial selectivity in old mice. In addition, young mice showed a broad
peak in the spatial selectivity between 4 and 10 min. In contrast old mice showed no peak in the spatial selectivity during
this time period. The stability of place fields after a 24-h interval was also lower in old mice than in young mice. The low
spatial tuning and unstable place fields suggest that a hippocampal-based spatial representation was impaired in the old mice.
Furthermore, we speculate that the age-related impairment in hippocampal inhibition system may be involved in the impaired
spatial representation of hippocampal CA1 place cells in old mice.
Electronic Publication 相似文献