全文获取类型
收费全文 | 55231篇 |
免费 | 2438篇 |
国内免费 | 422篇 |
专业分类
耳鼻咽喉 | 561篇 |
儿科学 | 1136篇 |
妇产科学 | 637篇 |
基础医学 | 7099篇 |
口腔科学 | 1096篇 |
临床医学 | 3352篇 |
内科学 | 14175篇 |
皮肤病学 | 1278篇 |
神经病学 | 3895篇 |
特种医学 | 2295篇 |
外科学 | 9818篇 |
综合类 | 231篇 |
一般理论 | 8篇 |
预防医学 | 1483篇 |
眼科学 | 1115篇 |
药学 | 3569篇 |
中国医学 | 199篇 |
肿瘤学 | 6144篇 |
出版年
2023年 | 293篇 |
2022年 | 621篇 |
2021年 | 1075篇 |
2020年 | 570篇 |
2019年 | 768篇 |
2018年 | 1068篇 |
2017年 | 785篇 |
2016年 | 1007篇 |
2015年 | 1131篇 |
2014年 | 1457篇 |
2013年 | 1845篇 |
2012年 | 3008篇 |
2011年 | 3424篇 |
2010年 | 1942篇 |
2009年 | 1739篇 |
2008年 | 3198篇 |
2007年 | 3380篇 |
2006年 | 3405篇 |
2005年 | 3356篇 |
2004年 | 3444篇 |
2003年 | 3489篇 |
2002年 | 3476篇 |
2001年 | 879篇 |
2000年 | 858篇 |
1999年 | 913篇 |
1998年 | 869篇 |
1997年 | 739篇 |
1996年 | 717篇 |
1995年 | 575篇 |
1994年 | 535篇 |
1993年 | 575篇 |
1992年 | 656篇 |
1991年 | 599篇 |
1990年 | 542篇 |
1989年 | 537篇 |
1988年 | 532篇 |
1987年 | 460篇 |
1986年 | 389篇 |
1985年 | 380篇 |
1984年 | 330篇 |
1983年 | 276篇 |
1982年 | 179篇 |
1981年 | 214篇 |
1980年 | 175篇 |
1979年 | 182篇 |
1978年 | 169篇 |
1977年 | 151篇 |
1976年 | 105篇 |
1975年 | 115篇 |
1974年 | 113篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
33.
Eiji Takeuchi Yuji Nimura Shin-ichi Mizuno Hideaki Suzuki Shinsuke Iyomasa Masaki Terasaki Hiroshi Kuriki Keiko Tamiya-Koizumi Shonen Yoshida 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(3):254-262
Hepatocyte regeneration has been widely investigated, with the mitotic index and the incorporation of [3H]thymidine being used as regeneration markers. We focused on the induction of DNA replication enzymes, particularly DNA polymerases
(pol) α, δ, and ε. Using rat models, we have shown that the activity of pol α in crude liver extract well represents the regenerating
capacity of hepatocytes. Using pol α as an indicator, we analyzed liver regeneration in rat models under various conditions:
obstructive jaundice, external or internal biliary drainage, and the obstruction of portal vein branches. It has been revealed
that the ligation of the common bile duct alone induces a certain amount of hepatocyte proliferation. It was striking that
external biliary drainage suppressed regeneration capacity in cholestatic rat liver after partial hepatectomy. The strong
regeneration in nonligated lobes induced by portal branch ligation was similar to the liver regeneration seen after partial
hepatectomy with respect to the induction of DNA polymerases. Taken together, the aspects of DNA replication, particularly
the induction of DNA polymerases, may contribute to shedding new light on the regeneration of human liver.
This work was supported in part by a Grant-in-Aid for General Scientific Research and for Cancer Research from the Ministry
of Education, Science and Culture, Japan, and by grants from the Uehara Memorial Foundation 相似文献
34.
K. Hamano Hiroshi Ito Andrew Bushell Kathryn J. Wood Kensuke Esato 《Transplant international》1997,10(4):293-298
In this study, the effect of combining anti-CD4 monoclonal antibody (mAb) and cyclosporin (CyA) therapy at the time of transplantation
was examined. A mouse cardiac allograft model was used. Anti-CD4 mAb administered perioperatively induces long-term survival.
The addition of a short course of CyA given subcutaneously in a regimen of either a high-dose treatment or a standard dose
treatment to the anti-CD4 mAb treatment protocol did not have a detrimental effect on graft survival. Despite having no significant
effect on graft survival, the addition of CyA to the treatment protocol did result in a significant decrease in the level
of IL-2 present in the hearts 7 days after transplantation. The decrease in IL-2 production was directly related to the presence
of CyA in vivo. When CyA treatment was continued throughout the period during which unresponsiveness to the graft is induced
by anti-CD4 mAb therapy, 50 % of the grafted hearts were rejected once the CyA was discontinued. In conclusion, the combined
use of anti-CD4 mAb therapy and CyA did not have a negative effect on graft survival in this model when the two agents were
used concurrently at the time of transplantation.
Received: 2 October 1996 Received after revision: 31 January 1997 Accepted: 5 February 1997 相似文献
35.
Tetsuo Nagatani Megumi Miyazawa Toshiko Matsuzaki Gaijiro Iemoto Shu-taku Kim Naoko Baba Kanata Miyakawa Hideaki Miyamoto Hiroshi Nakajima Yoshio Hirai 《The Journal of dermatology》1993,20(10):623-629
A 45-year-old man was referred to our department in March of 1989. Physical examination showed erythroderma, palmo-plantar hyperkeratosis, generalized lymphadenopathy, hepatosplenomegaly, and leukemic manifestation. The lymphocyte count in the peripheral blood before treatment was 1.7 × 104 cells/mm3. Atypical lymphocytes such as flower cells and lobulated cells were seen in the peripheral blood. A sample excised from a lymph node showed immunoblastic, pleomorphic T cells by a modified classification scheme of the Working Formulation. A high level of serum LDH was detected (2.1 times the upper normal limit). Anti HTLV-1 antibody was also detected in the serum. The atypical lymphocytes were positive for CD3, CD4, CD5, CD7 and HLA-DR, and negative for CD8. Thus, the clinical, pathologic and immunologic features were those of typical acute-type ATL. The patient was treated with VEPA-M for three months starting in March of 1989. Because of poor response, the patient was then treated with MACOP-B, M-FEPA, and VEPP-B for about one year from June of 1989 and has been free of disease up to the time of writing, March of 1993. 相似文献
36.
Shang-Jin Shi Hiromi Rakugi Koichi Higashimori Jitsuo Higaki Hiroshi Mikami Toshio Ogihara 《Clinical and experimental pharmacology & physiology》1994,21(10):767-773
1. We previously reported that angiotensin II release from the mesenteric arteries of Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) increased in a time-dependent manner as a result of the isolation of the arteries and perfusion. This phenomenon appeared to be due to the withdrawal of circulating angiotensin II (AII). 2. The purpose of the present study was to test the hypothesis that vascular AII generation may be negatively regulated by circulating AII in WKY and SHR, and to clarify the role of this vascular angiotensin II in the sustained hypertension of SHR following nephrectomy. 3. The mesenteric arteries from kidney-intact and nephrectomized WKY and SHR were perfused and the amount of AII released into the perfusate was measured. The effects of the angiotensin converting enzyme inhibitor, captopril, and the effects of supplementation of renal renin and circulating angiotensins to nephrectomized rats, by blood exchange between kidney-intact and nephrectomized rats, on AII release were examined to clarify the pathway of vascular AII generation after nephrectomy. 4. Nephrectomy caused augmentation of vascular AII release both in WKY and SHR in spite of the abolishment of circulating renin. Captopril reduced this enhanced release of AII, but blood exchange did not affect it. There was no significant difference in these responses between WKY and SHR. 5. These results suggest that WKY and SHR have in common a potent pathway for production of vascular AII in response to the withdrawal of circulating AII, although this pathway is not responsible for the sustained hypertension of SHR after nephrectomy. The precise pathophysiological role of this pathway remains to be elucidated. 相似文献
37.
Hiroshi Ujike Kazuo Tsuchida Kazufumi Akiyama Yutaka Fujiwara Shigetoshi Kuroda 《Pharmacology, biochemistry, and behavior》1995,50(4):613-617
The ontogeny of the behavioral effects of acute cocaine administration and behavioral sensitization to cocaine in rat pups was investigated. Acute behavior stimulating effects of cocaine were observed in pups as young as 7 postnatal days (PND) old, although they needed a higher dose of cocaine than adult rats to evoke the same motor effects. An adult dose-response curve pattern of stereotypy and locomotion to acute cocaine treatment was observed at PND 21, and of rearing at PND 28. Rats aged PND 7, 14, 21, 28, and 56 received repeated injections of saline or cocaine (15 mg/kg) twice a day for 5 consecutive days. After a 3-week period of abstinence, sensitization to a challenge dose of cocaine was assessed. Cocaine-induced stereotyped behavior was enhanced significantly only in rats in which cocaine pretreatment was initiated on PND 21, 28, and 56, but not earlier on PND 7 and 14. Adult female rats given repeated cocaine injections on PND 56–60 showed significantly greater sensitization than males, but no such sex difference was observed in pups given cocaine repeatedly on PND 21–25 or 28–32. These results show clearly that cocaine-induced behavioral sensitization in rats occurred only when subchronic cocaine administration was commenced on PND 21 or later. 相似文献
38.
K Fujita H Matsushima A Munakata T Kunitake 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1992,83(12):1999-2004
Multifactorial analysis on 395 patients revealed important factors which prolong the pyuria after transurethral prostatectomy. They were the age of the patient, anemia and leukocytosis before surgery. These are factors which relate with the defense mechanism of the patient. Local factors, such as the duration of indwelling urethral catheter, the size of the prostate or prostatic bed and preoperative infection, were not so important for prolonging the pyuria after transurethral prostatectomy. The time of the resection and weight of the prostate had an intimate relation each other, and the former was the more important factor. The use of antimicrobials probably controlled these local risk factors, thus making them unimportant in the prolongation of the pyuria after transurethral prostatectomy. 相似文献
39.
K Fujita 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1990,81(8):1140-1147
As morphological changes of the native kidneys, the presence of acquired cysts, intra-renal calcification and renal tumor was investigated mainly by ultrasonography and computed tomography in 151 patients with chronic renal failure. 1) Among 140 uremic patients caused by medical diseases. 40 patients had simple cysts, and 37 had acquired cystic disease of the kidneys (ACDK). However 4, uremic patients caused by urological diseases were not seen to be with an acquired cysts. 2) The patients with ACDK were with significantly longer durations of dialysis therapy than those with simple cysts or no cysts. Furthermore, the patients with ACDK were younger than those of the other groups. 3) Intra-renal calcification was more frequently found in patients with cystic disease (simple cyst, ACDK and polycystic disease) than in those without cystic disease with statistic significance. 4) Native kidneys became larger after the occurrence of ACDK. 5) Three cases of renal tumor were found. 相似文献
40.
Hiroshi Ohuchi Masataka Hatanaka Keiko Abe Shogo Yatsu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(6):302-304
Off-pump surgery was performed in a patient with post-infarction angina complicated with aneurysmal coronary-pulmonary arterial fistula. Epicardial echocardiography localized the artery feeding the fistula in the myocardium, which had not been revealed by visual inspection, palpation, or transesophageal echocardiography. The patient underwent off-pump coronary artery bypass grafting concomitant with aneurysmectomy. The feeding arteries were dissected easily using a Harmonic Scalpel and ligated. The flow in the aneurysm disappeared immediately and aneurysmectomy was performed without bleeding. 相似文献