全文获取类型
收费全文 | 1648篇 |
免费 | 82篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 29篇 |
儿科学 | 77篇 |
妇产科学 | 27篇 |
基础医学 | 171篇 |
口腔科学 | 16篇 |
临床医学 | 118篇 |
内科学 | 344篇 |
皮肤病学 | 108篇 |
神经病学 | 66篇 |
特种医学 | 80篇 |
外科学 | 220篇 |
综合类 | 85篇 |
预防医学 | 82篇 |
眼科学 | 14篇 |
药学 | 183篇 |
中国医学 | 5篇 |
肿瘤学 | 117篇 |
出版年
2022年 | 19篇 |
2021年 | 29篇 |
2020年 | 26篇 |
2019年 | 25篇 |
2018年 | 41篇 |
2017年 | 29篇 |
2016年 | 30篇 |
2015年 | 29篇 |
2014年 | 44篇 |
2013年 | 43篇 |
2012年 | 78篇 |
2011年 | 90篇 |
2010年 | 55篇 |
2009年 | 45篇 |
2008年 | 90篇 |
2007年 | 82篇 |
2006年 | 66篇 |
2005年 | 42篇 |
2004年 | 50篇 |
2003年 | 45篇 |
2002年 | 31篇 |
2001年 | 60篇 |
2000年 | 54篇 |
1999年 | 55篇 |
1998年 | 47篇 |
1997年 | 32篇 |
1996年 | 44篇 |
1995年 | 24篇 |
1994年 | 28篇 |
1993年 | 26篇 |
1992年 | 39篇 |
1991年 | 31篇 |
1990年 | 37篇 |
1989年 | 34篇 |
1988年 | 43篇 |
1987年 | 19篇 |
1986年 | 23篇 |
1985年 | 14篇 |
1984年 | 14篇 |
1983年 | 12篇 |
1982年 | 10篇 |
1981年 | 9篇 |
1980年 | 10篇 |
1979年 | 10篇 |
1977年 | 8篇 |
1976年 | 8篇 |
1975年 | 6篇 |
1974年 | 8篇 |
1973年 | 10篇 |
1972年 | 5篇 |
排序方式: 共有1742条查询结果,搜索用时 15 毫秒
1.
2.
3.
M S Bhatia P K Singhal V Rastogi N K Dhar V R Nigam S B Taneja 《Journal of the Indian Medical Association》1991,89(5):137-139
Twenty-four cases of trichotillomania attending psychiatry outpatient department and child guidance clinic at Kalawati Saran Children's and Smt Sucheta Kriplani Hospitals over a period of 2 years from July, 1985 to November 1987 were studied. Females (66.7%) outnumbered the males (33.3%). Majority of cases belonged to age group 6-10 years (54.2%) and nuclear family (68.5%). Nail-biting (25.0%) was the commonest associated neurotic trait, followed by enuresis (20.9%), temper-tantrum (12.5%), etc. A past history of hysterical fits and neurotic depression was found in 3 cases (12.5%) and 2 cases (8.3%) respectively. Family history of neurosis was seen in mothers and fathers of 20.9% and 12.5% cases respectively. Trichobezoars and trichophytobezoars were found in 6 cases (25.0%) and 3 cases (12.5%) respectively. Majority of patients of trichobezoars presented with vague complaints like heaviness in the stomach (55.6%), inability to gain weight (44.4%), etc, while 22.2% cases were asymptomatic and detected only on screening. 相似文献
4.
5.
6.
M Kaplan HJ Vreman C Hammerman C Leiter B Rudensky MG MacDonald DK Stevenson 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(4):455-457
The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia. 相似文献
7.
8.
Desensitization of platelet-activating factor-stimulated protein phosphorylation in platelets 总被引:1,自引:0,他引:1
Treatment of 32P-labeled rabbit platelets with platelet-activating factor (PAF) caused a time- and dose-dependent phosphorylation of several proteins including five major phosphorylated proteins with apparent molecular weights of 20,000, 35,000, 40,000, 65,000, and 150,000. Both PAF and thrombin caused a rapid increase followed by a decrease in phosphorylation of proteins, indicating the occurrence of a phosphorylation-dephosphorylation process. Four separate PAF receptor antagonists, CV-3988, CV-6209, SRI-63-441, and SRI-63-675 drastically reduced the PAF-stimulated protein phosphorylation. The order of potency was SRI-63675 greater than SRI-63441 greater than or equal to CV-6209 greater than CV-3988. These antagonists had no effect on thrombin-stimulated protein phosphorylation. Pretreatment of platelets with PAF (0.1 nM) completely abolished any further protein phosphorylation by the same concentration of PAF. PAF pretreatment shifted the dose response of protein phosphorylation by about 2 log units, to the right. When platelets were treated with PAF (10 nM) for 10 min, this abolished phosphorylation of proteins by any concentration of PAF. These studies indicated a homologous desensitization of protein phosphorylation. Interestingly, PAF-pretreated platelets still exhibited phosphorylation of proteins by thrombin. On the other hand, a lack of protein phosphorylation by PAF or thrombin was observed in platelets preexposed to thrombin and this demonstrated a heterologous desensitization. It is concluded that phosphorylation of proteins by PAF is a PAF receptor-coupled event and that this process is desensitized in platelets preexposed to PAF. The fact that both the activation of phosphoinositide-specific phospholipase C and the phosphorylation of proteins are desensitized in PAF-pretreated platelets suggests that a close "regulatory" intercommunication between these processes exists. 相似文献
9.
The 44-amino-acid E5 oncoprotein of bovine papillomavirus type 1 transforms immortalized murine fibroblast cell lines. This highly hydrophobic protein forms homodimers, localizes to intracellular membrane compartments (including the Golgi apparatus), and forms a complex with the 16-kDa membrane-embedded constituent (16k) of the vacuolar proton-ATPase. To develop a system for the genetic and biochemical analysis of the E5/16k interaction, the E5 gene was cloned into a new vector which was designed for expression in the fission yeast Schizosaccharomyces pombe. The E5 protein synthesized in this system dimerized normally and bound to endogenous and overexpressed S. pombe 16k protein. Comparison of the S. pombe and mammalian 16k proteins showed strong conservation in carboxyl-terminal amino acids but greater variation in the amino-terminal sequences, suggesting that E5 was interacting with the 16k carboxyl domains. Finally, a new protein epitope tag is described which permitted for the first time the coprecipitation of E5 with antibodies directed against the 16k protein. 相似文献
10.
Expression of cytoplasmic TFF2 is a marker of tumor metastasis and negative prognostic factor in gastric cancer 总被引:8,自引:0,他引:8
Dhar DK Wang TC Maruyama R Udagawa J Kubota H Fuji T Tachibana M Ono T Otani H Nagasue N 《Laboratory investigation; a journal of technical methods and pathology》2003,83(9):1343-1352
Trefoil factor family 2 (TFF2) is a small peptide constitutively expressed in the gastric mucosa, where it plays a protective role in restitution of gastric mucosa. TFF2 has also been shown to be expressed in some gastric cancers, but its role in tumor metastasis and patient prognosis has not been examined. In this study, we examined TFF2 expression at both the mRNA and protein levels and correlated these results with the clinicopathologic characteristics and prognosis of gastric cancer patients. Among the 144 curatively resected samples, 43 (30%) were positive for TFF2. TFF2 expression was preferentially observed in the infiltrating tumor cells sparing the superficial cells. Significantly increased expression of TFF2 was noted in large tumors of the diffuse type. An increased prevalence of TFF2 expression was also found in tumors with advanced T and N stage and in patients with lymphatic and venous invasion. Accordingly, patients with TFF2-expressing tumors had a significantly worse disease-free survival, and in multivariate analysis, this finding remained significant as an independent prognostic factor. Taken together, our results suggest that TFF2 expression may play a role in gastric cancer invasion and as such could be a useful target for therapeutic intervention. 相似文献