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81.
Kinds and locations of mutations arising spontaneously in the coding region of theHPRT gene of finite-life-span diploid human fibroblasts 总被引:1,自引:0,他引:1
W. Glenn McGregor Veronica M. Maher J. Justin McCormick 《Somatic Cell and Molecular Genetics》1991,17(5):463-469
Spontaneous thioguanine-resistant mutants were derived from populations of finite-life-span, diploid human fibroblasts by means of a fluctuation analysis. cDNA was prepared from mutantHPRT mRNA and amplified by the polymerase chain reaction, and the sequence of the product was analyzed. Exon deletions, which very likely arose from mutations in the intron splice site consensus sequences, were found in 10 of the 37 mutants examined (27% of the total). Among the 28 mutations in the coding sequence, base pair substitutions predominated (89%). With the exception of one base pair involved in a tandem mutation, all base pair substitutions resulted in alterations in the predicted amino acid sequence of the protein. In addition there were three frameshift mutations, consisting of the deletion of one or two base pairs. Although mutations occurred throughout the coding sequence, 50% (14/28) were found in the 5 portion of exon 3. 相似文献
82.
Blow FC Ullman E Barry KL Bingham CR Copeland LA McCormick R Van Stone W 《The American journal of orthopsychiatry》2000,70(3):389-400
This is the first study to test concurrently the effectiveness of four treatment programs for patients with serious mental illness. Three-year outcome data on utilization and functioning demonstrated important positive changes for seriously mentally ill veterans enrolled in specialized, enhanced inpatient and community case management treatment programs, when compared to patients in an enhanced day treatment program or traditional standard care. 相似文献
83.
84.
Complicated stent supported cerebrovascular angioplasty: case analyses and review of literature 总被引:2,自引:0,他引:2
Koenigsberg RA Dave A McCormick D Weiss J Higashida RT Faro SH Grandinetti LM Tsai FY 《Surgical neurology》2000,53(5):465-474
BACKGROUND: Hemodynamic lesions of the cervicocerebral vasculature are currently being treated with stent supported percutaneous transluminal angioplasty. These procedures have met with increasing success when compared to the risks and morbidity of more invasive surgical approaches. The versatility of stent-supported angioplasty as a primary therapeutic modality is examined in the following complex cases. CASE DESCRIPTION: We present four cases involving cervical angioplasty with emergent or adjunctive stent placement. Two cases involved the subclavian arteries, whereas the others involved the vertebral and internal carotid arteries. In our experience, complications of cervicocerebral artery angioplasty have been successfully managed by stent placement. CONCLUSION: Our cases demonstrate the emerging role of cervical angioplasty and stent implantation as a successful therapeutic modality, highlighted in these complex cases. 相似文献
85.
OBJECTIVES: To investigate maternal knowledge and attitudes about otitis media (OM) risk, to estimate the prevalence of risk factors in the first year of life, and to identify barriers to the reduction of risk factors (eg, formula feeding, day care attendance, and exposure to passive smoke). METHODS: Questionnaires mailed to a systematic sample of 504 Minnesota women >/=18 years old identified through 1994 birth certificates. RESULTS: Eighty percent returned a completed survey. According to maternal report, 29% of infants (age 8 to 13 months) had recurrent OM (>/=3 episodes) and 2% had tympanostomy tubes. Forty-six percent attended day care, 29% had >/=1 smoking parent, and 49% breastfed for =2 months. Women were more knowledgeable about OM signs and symptoms than about risk factors. Mean OM knowledge score (the sum of correct true-false responses) was 7.0 (standard deviation = 1.6). Using multiple linear regression, knowledge score was significantly related to marital status, education, age, area of residence, breastfeeding (months), and number of cigarettes smoked per day by the mother, but not to infant or sibling OM history or day care attendance (R = .23). Infant history of OM (odds ratio, 1.9; 95% confidence interval, 1.1 to 3.2) and white race (odds ratio, 0.3; 95% confidence interval, 0. 1 to 0.8), but not the presence of risk factors, were significantly related to having received clinicians' advice about OM prevention advice. CONCLUSION: OM education and prevention programs should target pregnant women and new mothers with OM risk factors, and those who are young, single, and less educated. 相似文献
86.
Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon 总被引:1,自引:1,他引:1
We have examined whether dietary polyamines influence the formation and
initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in
rat colon. Effects of a combination of dietary polyamines at three dose
levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g;
spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied
in animals in two different experimental situations: animals treated with
AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a
specific inhibitor of endogenous polyamine synthesis. In both experimental
situations, dietary polyamines enhanced the growth of ACF, expressed as the
number of large ACF (foci with three or more aberrant crypts, ACF > or =
3), whereas the formation of ACF, expressed as the number of ACF, was
apparently not altered. In animals treated with AOM alone, maximal growth
enhancing effect on ACF was nearly obtained with the median level of
dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO
reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of
DFMO was counteracted by dietary polyamines in a dose- dependent manner,
and it was abolished at the highest level of polyamines. In conclusion, it
was demonstrated that dietary polyamines are able to enhance the growth of
AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused
inhibition of ACF growth, probably by compensating for the DFMO-reduced
endogenous polyamine synthesis.
相似文献
87.
Circadian relationship of serum uric acid and nitric oxide 总被引:3,自引:0,他引:3
Kanabrocki EL Third JL Ryan MD Nemchausky BA Shirazi P Scheving LE McCormick JB Hermida RC Bremner WF Hoppensteadt DA Fareed J Olwin JH 《JAMA》2000,283(17):2240-2241
88.
Kehoe P Mallinson K McCormick CM Frye CA 《Brain research. Developmental brain research》2000,124(1-2):133-136
This experiment investigated whether neonatal isolation stress alters central concentrations of progestins. Whole brain progesterone (P), dihydroprogesterone (DHP), and allopregnanolone (3alpha, 5alpha-THP) were measured in pups that were isolated from the nest, dam, and siblings for 1 h on postnatal days (PND) 2-9 and were compared to control litters of pups that were not isolated. Isolated 2-day-old pups had significantly lower central P and higher P to DHP and 3alpha, 5alpha-THP metabolism ratios. On PND 9, pups that had been repeatedly isolated (PND 2-8), had significantly lower whole brain DHP and significantly greater whole brain 3alpha, 5alpha-THP compared to controls. Thus, the biosocial stress of isolation in neonatal rats alters central pregnane steroids. 相似文献
89.
90.
目的:验证二甲双胍治疗抗精神病药引起的血脂异常的疗效和安全性。方法:将两项随机、安慰剂的
对照研究纳入分析。共有201例服用抗精神病药物后出现血脂异常的首发精神分裂症患者,并将其分为1 000 mg/d
二甲双胍组(以下简称为二甲双胍组,n=103)和安慰剂组(n=98),观察24周。在基线、治疗后第12周和第24周进行
临床症状及体重、血糖、血脂等代谢指标的评估。结果:二甲双胍治疗后,二甲双胍组和安慰剂组之间低密度脂
蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)的平均差异从基线时的0.16 mmol/L,降低到第24周结束时的
–0.86 mmol/L,降低了1.02 mmol/L,差异有统计学意义(P<0.01)。而24周结束时,二甲双胍组LDL-C≥3.37 mmol/L的
患者有25.3%,显著低于安慰剂组24周结束时的64.8%(P<0.01)。与安慰剂组相比,二甲双胍组的体重、体重指数、
胰岛素、胰岛素抵抗指数、总胆固醇、三酰甘油和高密度脂蛋白胆固醇也有显著变化,差异均有统计学意义(均
P<0.05)。治疗对体重和胰岛素抵抗的影响出现在第12周,并且在第24周进一步改善,但对改善血脂异常的作用在第
24周结束时才出现。结论:二甲双胍治疗对于改善抗精神病药物引起的血脂异常和胰岛素抵抗是有效的,并且改善
抗精神病药物诱导的胰岛素抵抗出现的时间早于降低血脂异常的时间。 相似文献