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91.
目的构建人端粒酶逆转录酶(hTERT)片段的真核表达质粒。方法用RT-PCR方法从肝癌组织中提取总RNA扩增出hTERT基因片段,将其连接pGEM-TEasy质粒上,将重组质粒pGEM-T-hTERT和pEGFP-C3真核绿色荧光蛋白表达载体同时用HindⅢ和BamHⅠ双酶切后进行连接,再将重组的pEGFP-C3-hTERT基因片段转染NIH3T3细胞,经G418筛选获得稳定转染的细胞系,荧光倒置显微镜观察并检测转染细胞的hTERTmRNA表达水平。结果DNA序列分析证实了重组载体pGEM-T-hTERT和pEGFP-C3-hTERT内插入片段的碱基组成与公开发表的hTERT序列一致。转染pEGFP-C3-hTERT的NIH3T3细胞可见绿色荧光,并检出高水平表达的hTERT。结论成功构建高效表达hTERT的真核表达载体,为以hTERT为靶点的肿瘤治疗打下实验基础。 相似文献
92.
目的:该实验旨在研究急性肺损伤(ALI)时肺泡Ⅱ型上皮细胞(AEC-Ⅱ)超微结构变化和肺组织表面活性蛋白SP-A含量的变化关系,从而探讨ALI的发病机制。方法:48只Sprague-Dawley幼鼠被随机分为正常对照组和ALI组。 腹腔注射脂多糖(LPS,4 mg/kg)建立ALI模型,正常对照组注射等量生理盐水。 LPS注射后24,48,72 h每亚组各处死8只大鼠。 取左肺下肺组织待透射电镜检查。 用Western blot方法测定肺组织SP-A的相对含量。结果:ALI 24 h时,AEC-Ⅱ微绒毛消失。24 h及48 h时板层小体(lamellar body, Lb)数量增加,体积增大,密度减低,排空明显增强,呈指环状绕核排列,细胞增生活跃,代谢旺盛。48 h时Lb呈巨大空泡样变性。肺组织SP-A含量明显高于对照组(24 h时ALI组为6.52±0.62,对照组为5.02±0.35, P< 0.01;48 h时ALI组为6.65±0.62,对照组为5.01±0.36,P< 0.01)。72 h时Lb破溃,数目明显减少,细胞核形态不规则,部分核边界不清,肺组织SP-A含量下降(ALI组为3.87±0.50,对照组为5.22±0.36,P<0.01)。结论: LPS致幼鼠ALI时AEC-Ⅱ和肺组织SP-A的变化为时间依赖性,随AEC-Ⅱ损伤程度的加重肺组织SP-A由代偿转为失代偿,可能是发生ARDS的重要机制之一。 相似文献
93.
通过探讨细化药品采购环节:包括建立和完善采购制度,优选药品配送企业,制定合理的采购时间、合理采购价格和合理的库存结构及库存水平。以便及时、准确地为临床用药提供安全、有效、经济的药品以及全方位保障药品供应。 相似文献
94.
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96.
由于治疗方法的进步,近80%的儿童和青少年癌症患者能够长期生存。在美国,约有270000例儿童癌症的幸存者,即每640名20至39岁成年人中就有一名幸存者。大量的幸存者有利于儿童癌症治疗后长期健康结果的研究。现在可以明确的是,化疗和放疗所致的儿童各器官系统损害在临床上可能潜伏多年。为了全面了解治疗儿童癌症而继发的健康问题,重要的是衡量三项长期结果:健康状况、死亡率和患病率。这三项中,关于前两项已有相当好的研究报道。在一项对20227例癌症5年生存者的回顾性分析中,Mertens等发现以下原因导致的超额死亡率具有统计学意义:继发癌症(… 相似文献
97.
Mutations in Emery-Dreifuss muscular dystrophy and their effects on emerin protein expression 总被引:2,自引:1,他引:2
Manilal S; Recan D; Sewry CA; Hoeltzenbein M; Llense S; Leturcq F; Deburgrave N; Barbot J; Man N; Muntoni F; Wehnert M; Kaplan J; Morris GE 《Human molecular genetics》1998,7(5):855-864
Seventeen families with Emery-Dreifuss muscular dystrophy (EDMD) have been
studied both by DNA sequencing and by emerin protein expression. Fourteen
had mutations in the X-linked emerin gene, while three showed evidence of
autosomal inheritance. Twelve of the 14 emerin mutations caused early
termination of translation. An in-frame deletion of six amino acids from
the C-terminal transmembrane helix caused almost complete absence of emerin
from muscle with no localization to the nuclear membrane, although mRNA
levels were normal. This shows that mutant emerin proteins are unstable if
they are unable to integrate into a membrane. A 22 bp deletion in the
promoter region was expected to result in reduced emerin production, but
normal amounts of emerin of normal size were found in leucocytes and
lymphoblastoid cell lines. This shows that DNA analysis is necessary to
exclude emerin mutations in suspected X-linked EDMD. Emerin levels in
female carriers often deviated from the expected 50% and this was due, in
at least two families, to skewed emerin mRNA expression from the normal and
mutated alleles. In one family with a novel deletion of the last three
exons of the emerin gene, a carrier had a cardiomyopathy and very low
emerin levels (<5% of normal) due to skewed X-inactivation. In the three
autosomal cases of EDMD, emerin was normal on western blots of blood cells,
which suggests that autosomal EDMD is not caused by indirect reduction of
emerin levels.
相似文献
98.
Evaluation of a fluorescent monoclonal antibody reagent for identification of cultured Neisseria gonorrhoeae 总被引:2,自引:0,他引:2
We evaluated a new fluorescent monoclonal antibody reagent for confirmation of identity of Neisseria gonorrhoeae. The reagent correctly identified all 161 fresh clinical isolates of N. gonorrhoeae, which included 11 penicillinase producing strains (PPNG). The reagent also correctly identified 21 stored PPNG strains. No cross reactions were seen with 58 fresh clinical isolates of N. meningitidis, 12 stored strains of N. lactamica, or with strains of Gardnerella vaginalis, lactobacilli, Candida spp., Staphylococcus epidermidis or Enterobacteriaceae. Some cross reaction was noted with strains of S. aureus, probably related to cell-wall protein. A. However, this reagent was highly sensitive and specific for use against oxidase positive, gram-negative cocci isolated in London. 相似文献
99.
Llahi-Camp J.M.; Rai R.; Ison C.; Regan L.; Taylor-Robinson D. 《Human reproduction (Oxford, England)》1996,11(7):1575-1578
The aim of this study was to determine whether bacterial vaginosis(BV) is associated with a history of recurrent pregnancy loss.A total of 500 consecutive patients attending the RecurrentMiscarriage Clinic were screened for the presence of BV. Inwomen who had had at least one late miscarriage BV was foundtwice as commonly (27/130; 21%) as in women who had had onlyearly losses (31/370; 8%) (P<0.001). The difference was evenlarger (26 versus 8%) if women who had had term pregnancieswere excluded. Moreover, BV was found three times more commonlyin Afro-Caribbean women [17 (29%) of 58] than in Caucasian women[36 (9%) of 379] and, in both groups of women, BV was diagnosedat least twice as frequently in those with a history of at leastone late miscarriage than in those who had experienced firsttrimester pregnancy losses only (P<0.001). The conditionoccurred twice as often among smokers than non-smokers and,in both groups, it was at least twice as common in women witha history of at least one late miscarriage as in those who hadhad early pregnancy losses only (P<0.001). However, the relationshipbetween BV and smoking was independent of ethnic origin. Womenwho douched with chloroxylenol were mostly Afro-Caribbean andhad BV more than twice as often as women who did not douche. 相似文献
100.
No?l?BB?Knops Kommer?CA?Sneeuw Ronald?Brand Elysee?TM?Hille A?Lya?den Ouden Jan-Maarten?WitEmail author S?Pauline?Verloove-Vanhorick 《BMC pediatrics》2005,5(1):26