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101.
哺乳动物发育过程中细胞的重编程是当前细胞生物学、转化医学等领域研究的热点之一,因其在体细胞核移植、诱导多能干细胞及再生医学中的应用前景引起了广泛关注。表观遗传学修饰是重编程的主要内容,包括DNA甲基化、组蛋白翻译后修饰、基因组印迹、非编码RNA调控等,这些均可通过不同的机制调控基因组的表达。如卵母细胞发育与成熟过程伴随着基因组的从头甲基化、减数分裂相关基因的去甲基化和组蛋白翻译后的修饰等。此外,受精中,卵母细胞又与进入其中的雄原核发生相互作用,为雄原核基因组的去甲基化等过程提供重编程的环境。总结近年来关于卵母细胞发育和受精过程中重编程机制的研究进展及在胚胎发育中的意义,并探讨自然生殖状况下卵母细胞环境对外源性雄原核重编程的影响。  相似文献   
102.
103.
The Qiang population mainly lived in Beichuan Qiang Autonomous County of Sichuan Province. It is one of the nomads in China, distributed along the Minjiang River. The Qiang population was assumed to have great affinity with the Han, the largest ethnic group in China, when it refers to the genetic origin. Whereas, it is deeply understudied, especially from the Y chromosome. Here in this study, we used validated high-resolution Y-chromosome single nucleotide polymorphisms (Y-SNPs) and short tandem repeats (Y-STRs) panels to study the Qiang ethnic group to unravel their paternal genetic, forensic and phylogenetic characteristics. A total of 422 male samples of the Qiang ethnic group were genotyped by 233 Y-SNPs and 29 Y-STRs. Haplogroup O-M175 (N = 312) was the most predominant haplogroup in the Qiang ethnic group, followed by D-M174 (N = 32) and C-M130 (N = 32), N-M231 (N = 27), and Q-M242 (N = 15). After further subdivision, O2a-M324 (N = 213) accounted for the majority of haplogroup O. Haplogroup C2b-Z1338 (N = 29), D1a-CTS11577 (N = 30). O2a2b1a1a1-F42 (N = 48), O2a1b1a1a1a-F11 (N = 35), and O2a2b1a1-M117 (N = 21) represented other large terminal haplogroups. The results unveiled that Qiang ethnic group was a population with a high percentage of haplogroup O2a2b1a1a1-F42 (48/422) and O2a1b1a1a1a-F11 (35/422), and O2a2b1a1-M117 (21/422), which has never been reported. Its haplogroup distribution pattern was different from any of the Han populations, implying that the Qiang ethnic group had its unique genetic pattern. Mismatch analysis indicated that the biggest mismatch number in haplogroup O2a2b1a1a1-F42 was 21, while that of haplogroup O2a1b1a1a1a-F11 was 20. The haplotype diversity of the Qiang ethnic group equaled 0.999788, with 392 haplotypes observed, of which 367 haplotypes were unique. The haplogroup diversity of the Qiang ethnic group reached 0.9767, and 53 terminal haplogroups were observed (The haplogroup diversity of the Qiang ethnic group was the highest among Qiang and all Han subgroups, indicating the larger genetic diversity of the Qiang ethnic group.). Haplogroup O2a2b1a1a1-F42 was the most predominant haplogroup, including 11.37 % of the Qiang individuals. Median-joining trees showed gene flow between the Qiang and Han individuals. Our results indicated that 1) the highest genetic diversity was observed in the Qiang ethnic group compared to any of the former studied Chinese population, suggesting that the Qiang might be an older paternal branch; 2) the haplogroup D-M174 individuals of Qiang, Tibetans and Japanese distributed in three different subclades, which was unable to identify through low-resolution Y-SNP panel; and 3) the Qiang had lower proportion of haplogroup D compared to Yi and Tibetan ethnic groups, showing that the Qiang had less genetic communication with them than with Han Chinese.  相似文献   
104.
Anxiety and depression commonly occur in the pathology of rheumatic diseases. Little is known about how inflammatory disease in its early stage, before any clinical manifestation, may affect general activity. The aim of this study was to compare the anxiety-like behaviour in the early stage of adjuvant arthritis (AA), and the paw edema, and corticosterone (CORT) levels in the developed stage of AA among male and female Long Evans rats. The behavioural activity was evaluated by elevated plus maze tests. These revealed significantly reduced number of entries into the open arm of the maze in arthritic males compared to controls or to females 4 days after AA induction. Arthrihtic and control females did not differ. The number of entries into the closed arm of the maze was the same across the genders and studied intervals. Time spent in the open arm was significantly lower in arthritic males against controls or arthitic females. Time spent in the closed arm showed inverse picture to the time spent in the open arm. Hind paw swelling measured on day 23 of AA was the same in males and females, as was the elevation of CORT levels in plasma. Male rats showed anxiety-like behaviour on day 4 of AA, while female rats did not show any change, indicating different brain sensitivity to early inflammation among the genders.  相似文献   
105.
日本血吸虫尾蚴成虫及虫卵的早期诊断组分抗原分析   总被引:4,自引:2,他引:4  
目的寻找具有血吸虫病早期诊断价值的组分抗原.方法以感染后不同时间的兔血清,用SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)和免疫印迹试验(Western blotting)方法,对日本血吸虫尾蚴、成虫和虫卵中的可溶性抗原的成分进行免疫分析.结果可溶性尾蚴抗原(SCA)94、48、41、40 kDa和38 kDa组分抗原最早出现免疫印迹反应,能被感染后2周兔血清所识别,可被感染后3周兔血清识别的SCA 71、23 kDa组分抗原反应最强.可溶性成虫抗原(AWA)最早出现反应的组分抗原是71、58 kDa,能被感染后3周兔血清所识别.可溶性虫卵抗原(SEA)最早出现反应的组分抗原是270、151、73、69、50 kDa和24 kDa,能被感染后4周兔血清所识别.结论 SCA 94、71、48、41、40、38、23 kDa,AWA 71、58 kDa和SEA 270、151、73、69、50、24 kDa能被急性感染兔血清所识别,是具有潜在早期诊断价值的组分抗原.  相似文献   
106.
弓形虫感染对雄性小鼠睾丸细胞周期影响的实验研究   总被引:2,自引:0,他引:2  
目的 研究弓形虫感染对雄性小鼠睾丸组织细胞周期的影响。方法 应用流式细胞术检测弓形虫感染10 3/ ml、10 4 / ml、10 6 / ml3个剂量组小鼠睾丸组织细胞周期,并设立生理盐水和环磷酰胺对照组。结果 不同剂量的弓形虫感染均可使小鼠睾丸组织细胞各时相的细胞百分数发生变化,并随着剂量的增加,G0 / G1 、S时相的细胞百分数明显减少,与阴性对照组比较差异有显著性(P<0 .0 5 )。G2 / M时相的细胞百分数逐渐增多,各剂量组与阴性对照组比较差异有显著性(P<0 .0 5 )。结论 弓形虫感染可能抑制小鼠睾丸细胞的DNA合成,可引起G2 期细胞阻滞,从而使细胞的有丝分裂延伸。  相似文献   
107.
高氟对成年男性生殖内分泌功能的影响   总被引:5,自引:1,他引:5  
为了探讨高氟对成年男性生殖功能的影响,对地方性氟中毒重病区的31名成年男性(20~55岁)及26名对照人群的有关生殖内分泌指标进行了检测,结果显示:高氟区人群血清黄体生成素(LH)、卵泡刺激素(FSH)较对照组明显升高(P<0.001);血清睾酮(T)水平则显著降低(P<0.01),表明高氟状态能够影响成年男性的生殖内分泌功能。  相似文献   
108.
男性乙型肝炎肝硬化患者血清瘦素及血脂水平的研究   总被引:1,自引:0,他引:1  
目的检测男性乙型肝炎肝硬化患者血清瘦素及血脂水平,探讨其异常变化的临床意义。方法男性乙型肝炎肝硬化患者64例,男性健康受试者28名,用ELISA法检测血清瘦素水平,用全自动生化分析仪检测肝功能和血脂。对血清瘦素、血脂与肝功能的关系进行分析。结果各组乙型肝炎肝硬化Child-Pugh分级患者与对照组比,血清瘦素水平无显著性差异(P〉0.05);与正常对照组比,乙型肝炎肝硬化患者血CHO和LDL水平显著降低(P〈0.01),按Child分级由A到C级各组CHO和LDL水平逐渐降低,差异有显著性(P〈0.01)。无腹水肝硬化患者血清瘦素水平与BMI及Fat%均呈显著正相关。结论血清瘦素水平不能作为评价男性乙型肝炎肝硬化患者病情严重程度的指标,血清胆固醇、低密度脂蛋白是肝功能减退的指标。瘦素可能参与了男性乙型肝炎肝硬化患者的营养不良。  相似文献   
109.
Edgar Degas (1834–1917) is not only an impressionistic painter when he is painting the society of his time. He shows the relationship between men and women, into the family first, secondly into the society, then at the opera and finally in brothels. No reserve into this last universe from where rise dramas between men and women. In the 21st century, what can we say about these relationships? What are their actual expressions?  相似文献   
110.
The purpose of this study was to investigate the effect of dietary vitamin E and vitamin C, probiotics mixture and protein level and their combination on semen quality and immunohistochemical study of some pituitary hormones in male broiler breeders. One hundred and eighty male broiler breeders 65 weeks old were divided into six groups by completely randomized design. The birds were subjected to zinc-induced molt by mixing zinc oxide at the rate of 3000 mg/kg in the feed. After molting, one group was fed control diet (CP16%). The other groups were fed vitamin E (100 IU/kg), vitamin C (500 IU/kg), probiotics (50 mg/L of drinking water), protein (CP14%) and combination of these components. These treatments were given for five weeks. After the feeding period, semen samples were taken and analyzed for semen volume, sperm concentration, motility and dead sperm percentage. Pituitary samples were collected from three birds per replicate and were processed for immunohistochemical study. The results of semen quality parameters revealed that semen volume and sperm motility were significantly high in the vitamin E fed group, while the dead sperm percentage decreased significantly in the vitamin C group. The morphometric analysis revealed that compared to other groups, vitamin E caused a significant increase in the size and area of FSH, LH gonadotropes and lactotropes. These results showed that vitamin E alone may play some role in the enhancement of semen quality and growth of gonadotropes and lactotropes.  相似文献   
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