全文获取类型
收费全文 | 1231篇 |
免费 | 110篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 37篇 |
儿科学 | 40篇 |
妇产科学 | 44篇 |
基础医学 | 145篇 |
口腔科学 | 41篇 |
临床医学 | 98篇 |
内科学 | 356篇 |
皮肤病学 | 44篇 |
神经病学 | 61篇 |
特种医学 | 30篇 |
外科学 | 159篇 |
综合类 | 9篇 |
预防医学 | 56篇 |
眼科学 | 8篇 |
药学 | 104篇 |
中国医学 | 6篇 |
肿瘤学 | 113篇 |
出版年
2024年 | 2篇 |
2023年 | 23篇 |
2022年 | 32篇 |
2021年 | 45篇 |
2020年 | 35篇 |
2019年 | 48篇 |
2018年 | 44篇 |
2017年 | 36篇 |
2016年 | 41篇 |
2015年 | 53篇 |
2014年 | 52篇 |
2013年 | 65篇 |
2012年 | 97篇 |
2011年 | 104篇 |
2010年 | 61篇 |
2009年 | 48篇 |
2008年 | 73篇 |
2007年 | 58篇 |
2006年 | 47篇 |
2005年 | 45篇 |
2004年 | 45篇 |
2003年 | 34篇 |
2002年 | 38篇 |
2001年 | 27篇 |
2000年 | 12篇 |
1999年 | 22篇 |
1998年 | 9篇 |
1997年 | 8篇 |
1996年 | 7篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 4篇 |
1992年 | 11篇 |
1991年 | 18篇 |
1990年 | 11篇 |
1989年 | 14篇 |
1988年 | 15篇 |
1987年 | 5篇 |
1986年 | 6篇 |
1985年 | 4篇 |
1983年 | 2篇 |
1979年 | 5篇 |
1973年 | 2篇 |
1972年 | 4篇 |
1971年 | 4篇 |
1970年 | 5篇 |
1969年 | 7篇 |
1968年 | 4篇 |
1967年 | 2篇 |
1966年 | 4篇 |
排序方式: 共有1351条查询结果,搜索用时 15 毫秒
91.
Seki N Sekijima K Tanabe N Suzuki H 《[Nihon kōshū eisei zasshi] Japanese journal of public health》2004,51(4):252-256
PURPOSE: To assess a smoking rate survey using the coming-of-age ceremony to examine the practicality for estimating the under twenties' smoking rate as a baseline and a long term assessment index for action plans to prevent smoking in the young. METHODS: We undertook the survey at village A (with a population of about 6,500) and town B (with about 12,000 residents) in Niigata Prefecture. Village A started a comprehensive anti-smoking policy featuring cooperation between schools and the community. Subjects were twenty-year young adults (69 in village A and 118 in town B) who attended rural coming-of-age ceremonies in 2002. The self-rated questionnaire included smoking habits, age of first smoking experience, and age of becoming a regular smoker (only in village A). RESULTS: Smoking rates were 68.0% for men and 48.6% for women in village A. Of these, approximately 90% smoked daily and more than 70% became regular smokers before the age of 20. Smoking rates in town B were similar. The results were about 20% higher than found by a smoking rate survey performed at high schools. CONCLUSION: Smoking rate surveys at coming-of-age ceremonies offer a practical and easy approach to estimate under twenties' smoking rate and assess the effects of smoking prevention strategies among the young. 相似文献
92.
Yamamoto N Nakayama J Yamakawa-Kobayashi K Hamaguchi H Miyazaki R Arinami T 《Human mutation》2002,19(3):251-257
Adipocyte-derived leucine aminopeptidase (ALAP) inactivates angiotensin II and/or generates bradykinin in the kidney, suggesting a possible role for ALAP in the regulation of blood pressure. We considered the hypothesis that genomic variants of the ALAP gene are associated with hypertension or individual variations in blood pressure. We screened for mutations in the ALAP gene in 48 unrelated Japanese individuals and identified 33 polymorphisms including 15 novel polymorphisms. We then performed a two-stage analysis. In the first stage, the eight missense polymorphisms were evaluated for associations with blood pressure in 96 apparently healthy individuals. In the second stage, only the most promising polymorphisms were evaluated for association with essential hypertension in 143 hypertensive and 348 normotensive subjects. Among the eight missense polymorphisms, the Ile276Met and Lys528Arg polymorphisms showed significant association with blood pressure. Subsequent analysis confirmed association between the Lys528Arg polymorphism and essential hypertension. The estimated odds ratio for essential hypertension was 2.3 for presence of the Arg allele at codon 528, in comparison with presence of the Lys/Lys genotype (P = 0.004). These findings support involvement of ALAP in the regulation of blood pressure. 相似文献
93.
Yoshikawa D Kawahara F Okano N Hiraoka H Kadoi Y Fujita N Morita T Goto F 《Anesthesia and analgesia》2003,97(3):663-670
Adrenomedullin is a potent vasodilatory peptide. Plasma adrenomedullin (AM) concentrations increase during and after cardiopulmonary bypass (CPB). However, the cause of this increase and its site of production have not been identified. We investigated the role of the hepatosplanchnic and cerebral circulations in the increase of plasma AM and investigated whether tissue hypoxygenation is a cause of the AM increase seen during CPB. We measured plasma total AM (AM-T) and the biologically active form of AM, mature AM (AM-m), in seven patients undergoing CPB. Both plasma AM-T and AM-m concentrations increased significantly 60 min after weaning from CPB. At this time point, arterial AM-T and AM-m concentrations were 18-fold and 10-fold larger, respectively, than baseline values measured after the induction of anesthesia. The plasma AM-m concentration and the ratio of AM-m/AM-T in blood from the hepatic vein were significantly larger than those from the radial artery or jugular bulb. The AM-m/AM-T ratio decreased during CPB, suggesting that production of the intermediate form of AM, AM-glycine, is more than that of AM-m. The oxygen tension of the hepatic venous blood (PhvO2) was significantly less during CPB. Plasma AM-m concentrations sampled from the hepatic vein showed a significant negative correlation with PhvO2 at 10 min (r = 0.824; P < 0.02) and 60 min (r = 0.828; P < 0.02) after the onset of CPB. These data suggest that the hepatosplanchnic circulation is an important source of AM-m during CPB. Furthermore, hypoxygenation of the hepatosplanchnic region may be an important cause of this AM-m increase. 相似文献
94.
Satomoto M Aoki H Tobita M Shiohara N Adachi Y Higuchi H Watanabe K Satoh T 《Masui. The Japanese journal of anesthesiology》2003,52(5):527-529
We report 3 patients who developed a sudden unpredicted increase in bispectral index (BIS) value during propofol and fentanyl anesthesia. The patients were induced with propofol 2-mg.kg-1 and fentanyl 2-micrograms.kg-1 and muscle relaxation was obtained by vecuronium 0.12-mg.kg-1. During induction of anesthesia, BIS value went down to below 50 in all three cases, and anesthesia was maintained by continuous infusion of propofol at a rate of 5 mg.kg-1.hr-1 and intermittent administration of fentanyl. Forty to sixty min after starting the operation, BIS value increased suddenly (up to 80) and the body movement of the patients was observed. The serum concentration of propofol was approximately 2.5 micrograms.ml-1. All patients were successfully treated with increasing the infusion rate of propofol and additional administration of fentanyl. No clear recall or explicit memory during operation was observed after anesthesia, but, anesthesiologists might have to pay more attention to unpredictable changes of anesthetic depth during propofol anesthesia using target controlled infusion. 相似文献
95.
The calpains, a family of calcium-dependent cysteine proteinases, and calpastatin, their endogenous inhibitor protein, are involved in the proteolysis of amyloid precursor protein, which is thought to be abnormal in patients with Alzheimer's disease (AD). Specific inhibitors of calpains attenuate amyloid beta peptide-induced neuronal death. We hypothesized that some AD patients have functionally deficient mutation(s) of the CAST gene encoding calpastatin, and we screened 40 Japanese patients with AD for mutations in the coding region of CAST. Nine polymorphisms, -82A/G, IVS7-96A/G, 669A/G, 1223C/G (Ser408Cys), IVS20-10C/T, IVS21-65G/A, IVS22+31T/C, IVS24+38Ins/DelA, and IVS25-32A/G, were identified. The 669A allele causes skipping of exon 11, leading to the loss of 13 residues. Comparisons between 101 patients and 90 controls revealed no significant association between CAST polymorphisms and risk for AD, indicating that genomic variations of CAST are not likely to be substantially involved in the etiology of AD. 相似文献
96.
Persistence of a small subpopulation of cancer stem-like cells in the C6 glioma cell line 总被引:123,自引:0,他引:123 下载免费PDF全文
Kondo T Setoguchi T Taga T 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(3):781-786
Both stem cells and cancer cells are thought to be capable of unlimited proliferation. Paradoxically, however, some cancers seem to contain stem-like cells (cancer stem cells). To help resolve this paradox, we investigated whether established malignant cell lines, which have been maintained for years in culture, contain a subpopulation of stem cells. In this article, we show that many cancer cell lines contain a small side population (SP), which, in many normal tissues, is thought to contain the stem cells of the tissue. We demonstrate that in the absence of serum the combination of basic fibroblast growth factor and platelet-derived growth factor maintains SP cells in the C6 glioma cell line. Moreover, we show that C6 SP cells, but not non-SP cells, can generate both SP and non-SP cells in culture and are largely responsible for the in vivo malignancy of this cell line. Finally, we provide evidence that C6 SP cells can produce both neurons and glial cells in vitro and in vivo. We propose that many cancer cell lines contain a minor subpopulation of stem cells that is enriched in an SP, can be maintained indefinitely in culture, and is crucial for their malignancy. 相似文献
97.
98.
99.
H Yasumatsu Y Yamamoto H Takamuku K Anami S Takehara M Setoguchi Y Maruyama 《Nihon yakurigaku zasshi. Folia pharmacologica Japonica》1987,90(6):321-330
The effects of Y-8894 on experimental amnesia in rats induced by transient cerebral ischemia (600 sec) according to the method of Pulsinelli and Brierley were studied using the one trial passive avoidance response and the pole climbing discrete avoidance response. All drugs were administered to the rats immediately after recirculation. The following results were obtained: 1) In the one trial passive avoidance response test, Y-8894 (2.5, 5 and 10 mg/kg, i.p.) improved significantly the decreased latency induced by the ischemia, and it was most effective at 5 mg/kg. Calcium-hopantenate (100, 250 and 500 mg/kg, i.p.) and dihydroergotoxine (5 and 10 mg/kg, i.p.) tended to increase the latency. On the other hand, physostigmine (0.025, 0.05 and 0.1 mg/kg, i.p.), a cholinesterase inhibitor, increased the latency significantly, and it was most effective at 0.05 mg/kg. 2) The pole climbing discrete avoidance response was significantly decreased by the ischemia compared with the sham operated group, and Y-8894 (5 mg/kg, i.p.) tended to improve this decreased avoidance response. 3) Y-8894 (5 mg/kg, i.p.) facilitated recovery from the changes in glycolytic metabolism, and inhibited the accumulation of choline due to the dysfunction of the neuronal membranes induced by the ischemia. These results show that Y-8894 has beneficial effects on experimental amnesia induced by transient cerebral ischemia. 相似文献
100.
M Setoguchi S Takehara M Sakamori K Anami Y Maruyama 《Nihon yakurigaku zasshi. Folia pharmacologica Japonica》1987,90(1):41-49
The effect of Y-8894 (+/-) 2-[[o-(2-thenyl)phenoxy]methyl] morpholine maleate, which has been shown to improve experimentally induced learning and memory deficits, on cerebral monoamine uptake and turnover was studied in the mouse. The following results were obtained: 1) It inhibited in vitro norepinephrine (NE) uptake to the mouse cerebral synaptosomal fractions about 800 and 1250 times more potently than it did those of dopamine (DA) and serotonin (5-HT), respectively. 2) It dose-dependently inhibited in vivo NE uptake, but not DA or 5-HT uptake. 3) It reduced the accumulation of the NE metabolite, 3-methoxy-4-hydroxyphenylglycol (MHPG), increased that of the 5-HT metabolite, 5-hydroxyindoleacetic acid (5-HIAA), and had no effect on that of the DA metabolite, homovanillic acid (HVA). These effects were compared with those of imipramine, calcium hopantenate (Ca-hopantenate) and dihydroergotoxine. Y-8894 appeared to act by stimulating the noradrenergic receptor, and it acts to a lesser extent by blocking the serotonergic receptor in the brain. 相似文献