全文获取类型
收费全文 | 5327篇 |
免费 | 218篇 |
国内免费 | 27篇 |
专业分类
耳鼻咽喉 | 24篇 |
儿科学 | 90篇 |
妇产科学 | 80篇 |
基础医学 | 741篇 |
口腔科学 | 146篇 |
临床医学 | 301篇 |
内科学 | 1438篇 |
皮肤病学 | 52篇 |
神经病学 | 350篇 |
特种医学 | 175篇 |
外国民族医学 | 2篇 |
外科学 | 966篇 |
综合类 | 52篇 |
预防医学 | 167篇 |
眼科学 | 53篇 |
药学 | 291篇 |
中国医学 | 53篇 |
肿瘤学 | 591篇 |
出版年
2024年 | 8篇 |
2023年 | 25篇 |
2022年 | 63篇 |
2021年 | 106篇 |
2020年 | 64篇 |
2019年 | 70篇 |
2018年 | 92篇 |
2017年 | 77篇 |
2016年 | 76篇 |
2015年 | 90篇 |
2014年 | 124篇 |
2013年 | 145篇 |
2012年 | 310篇 |
2011年 | 337篇 |
2010年 | 174篇 |
2009年 | 185篇 |
2008年 | 284篇 |
2007年 | 343篇 |
2006年 | 346篇 |
2005年 | 397篇 |
2004年 | 376篇 |
2003年 | 390篇 |
2002年 | 398篇 |
2001年 | 40篇 |
2000年 | 53篇 |
1999年 | 85篇 |
1998年 | 102篇 |
1997年 | 102篇 |
1996年 | 97篇 |
1995年 | 76篇 |
1994年 | 49篇 |
1993年 | 52篇 |
1992年 | 35篇 |
1991年 | 28篇 |
1990年 | 33篇 |
1989年 | 32篇 |
1988年 | 32篇 |
1987年 | 21篇 |
1986年 | 33篇 |
1985年 | 24篇 |
1984年 | 24篇 |
1983年 | 22篇 |
1982年 | 15篇 |
1981年 | 23篇 |
1980年 | 18篇 |
1979年 | 16篇 |
1978年 | 13篇 |
1977年 | 13篇 |
1976年 | 11篇 |
1975年 | 10篇 |
排序方式: 共有5572条查询结果,搜索用时 15 毫秒
111.
112.
Ohkusa T Miwa H Endo S Okayasu I Sato N 《Journal of gastroenterology and hepatology》2004,19(2):200-204
BACKGROUND AND AIM: Usually, bacteria are cryopreserved for short-term storage at low and ultra-low temperatures. There are no reports as to whether Helicobacter pylori is a fragile bacteria when stored at low and ultra-low temperatures as compared with other intestinal bacteria. A study was done on seven H. pylori strains and other intestinal bacteria to compare different temperatures for storage of organisms in saline solution. METHODS: Seven H. pylori strains, specifically American Type Culture Collection (ATCC) strains 43504 and TN2GF4, and five strains isolated from the present patients were grown on a modified Skirrow's agar for H. pylori. Escherichia coli and Bacteroides distasonis, both representing isolates from the present patients, were grown on trypticase soy blood agar for E. coli, and EG agar for B. distasonis. Culture was for 4-5 days under microaerobic, aerobic and anaerobic conditions at 37 degrees C. Cells were harvested by scraping growth from the solid medium and into sterile saline. The cells were adjusted to concentrations of 109 viable cells/mL in saline and preserved at 4 degrees C, -20 degrees C, or -80 degrees C for 3 weeks before reculture under microaerobic, aerobic and anaerobic conditions at 37 degrees C for 7 days. After incubation, morphologically distinct colonies were counted, isolated, and identified by standard bacteriologic techniques. The H. pylori were morphologically analyzed by electronic microscopy before and after preservation. Mongolian gerbils were inoculated with the cryopreserved H. pylori to evaluate the bacterial infectivity. RESULTS: Six of the seven H. pylori strains failed to culture after being preserved at 4 degrees C, -20 degrees C, or -80 degrees C. Only ATCC 43504 could be cultured after freezing at -80 degrees C. The number of H. pylori ATCC 43504 before preservation was 9.0 +/- 0.5 (log10 no. organisms/mL) and decreased to 5.7 +/- 0.6 after preservation. Morphologically, all H. pylori except ATCC 43504 strains transformed from a bacillary to a coccoid form after preservation. In addition, none of the H. pylori strains could infect Mongolian gerbils after preservation. Escherichia coli and B. distasonis were recovered. Titers before and after 4 degrees C, -20 degrees C, and -80 degrees C, respectively, were 9.1 +/- 0.2, 8.9 +/- 0.5, 8.6 +/- 0.3, and 8.7 +/- 0.3 for E. coli and 9.1 +/- 0.4, 8.7 +/- 0.6, 8.6 +/- 0.5, and 8.8 +/- 0.3 for B. distasonis. CONCLUSIONS: Helicobacter pylori is a fragile bacteria for storage at low and ultra-low temperatures in comparison with other intestinal bacteria. 相似文献
113.
Dr. Masao Arai MD Maki Niioka BS Katsuya Maruyama MD Norihito Wada MD Noboru Fujimoto PhD Tetsu Nomiyama MD Shoutarou Tanaka MD Isao Okazaki MD 《Digestive diseases and sciences》1996,41(5):995-1000
We treated 18 patients with chronic hepatitis C by recombinant interferon-α (6 MIU for 24 weeks). In seven patients, serum aminotransferase levels declined to normal (responders). To evaluate the effect of interferon on matrix metalloproteinases (MMPs) and their inhibitors, namely tissue inhibitors of metalloproteinases (TIMPs), the serum levels of these enzymes were determined by enzyme immunoassay (EIA) using a specific monoclonal antibody. In responders, there was a tendency, but not a significant one, towards either an increase in serum MMP 1 levels or a decrease in serum TIMP 1 levels. In contrast, in nonresponders, both a significant decrease in MMP 1 and MMP 3 and a significant increase in TIMP 1 were observed. The number of cases of either increase in serum MMP levels or decrease in serum TIMP levels was significantly larger in responders than in nonresponders. Furthermore, the ratio of MMP 1 to TIMP 1 significantly increased in responders, suggesting that the balance between matrix formation and degradation in hepatic fibrosis tended to move toward degradation. These data indicate that interferon may exert a beneficial effect on hepatic fibrosis in parallel with improvement of aminotransferase activity. 相似文献
114.
Kozo Kayano Mitsuru Yasunaga Masafumi Kubota Kazuyuki Takenaka Kenji Mori Aogu Yamashita Yoshitsugu Kubo Isao Sakaida Kiwamu Okita Kazutoshi Sanuki 《Liver international》1992,12(3):132-136
ABSTRACT— This study evaluated whether liver regeneration could take place after massive or submassive necrosis of liver cells in 25 patients with several kinds of hepatic failure by immunohistochemical staining for proliferating cell nuclear antigen (PCNA). PCNA positivity was significantly higher (P<0.01) in the patients who survived than in the patients who died. Furthermore, PCNA-positive hepatocytes were recognized diffusely in the lobule of the liver in survivors. There was positive correlation between PCNA positivity and plasma concentration of AFP (α-fetoprotein), (r = 0.77, P<0.01). These results show that liver regeneration could take place after massive necrosis of liver cells in survivors from acute hepatic failure and that immunohistochemical staining for PCNA is useful for prognostic evaluation. 相似文献
115.
Fatema K Hirono O Takeishi Y Nitobe J Kaneko K Ito M Masakane I Kubota I 《Heart and vessels》2002,16(6):227-231
Congestive heart failure is the most common cause of mortality in patients with end-stage renal disease (ESRD). Ultrasonic
tissue characterization with integrated backscatter offers a promising method for the noninvasive assessment of regional myocardial
contractile performance and fibrosis. The aim of this study was to investigate the effect of hemodialysis (HD) on myocardial
tissue characterization and left ventricular function in ESRD patients. We examined 26 patients with ESRD undergoing routine
HD (age 63 ± 12 years, duration of HD 9.2 ± 3.2 years) and 30 patients with essential hypertension (HT; 60 ± 10 years). Routine
echocardiographic parameters and the cyclic variation of ultrasonic integrated backscatter of the ventricular septum (CV-IBS)
were measured. Left ventricular mass index was significantly larger in patients with ESRD than in those with HT (217 ± 56
vs 146 ± 45 g/m2, P < 0.05). The indices for left ventricular diastolic function (E/A, the ratio of left ventricular peak early to late diastolic
filling velocity; DT, the deceleration time of the early diastolic filling) and CV-IBS had deteriorated significantly in patients
with ESRD before HD compared with those with HT (E/A, 0.6 ± 0.2 vs 0.9 ± 0.3, P < 0.05; DT, 228 ± 23 vs 184 ± 19 ms, P < 0.05; CV-IBS, 9.0 ± 1.3 vs 12.4 ± 0.9 dB, P < 0.05), possibly reflecting interstitial fibrosis. In patients with ESRD, HD reduced calculated left ventricular mass index
by 19% (before HD, 217 ± 56 vs immediately after HD, 176 ± 45 g/m2, P < 0.05) and CV-IBS by 19% (9.0 ± 1.3 vs 7.3 ± 1.1 dB, P < 0.05), that possibly reflected improvement of interstitial edema. HD also significantly improved indices for left ventricular
diastolic function (E/A, 0.6 ± 0.2 vs 0.9 ± 0.2, P < 0.05; DT, 228 ± 23 vs 188 ± 21 ms, P < 0.05). HD improves myocardial interstitial edema and left ventricular diastolic function in patients with ESRD. Noninvasive
assessment of ultrasonic tissue characterization is useful in defining the pathophysiological changes of ventricular myocardium
in patients with ESRD.
Received: December 17, 2001 / Accepted: April 19, 2002
Correspondence to O. Hirono 相似文献
116.
Isozumi R Ito Y Ito I Osawa M Hirai T Takakura S Iinuma Y Ichiyama S Tateda K Yamaguchi K Mishima M 《Scandinavian journal of infectious diseases》2005,37(10):709-711
We report 2 cases of Legionella pneumonia in individuals who were exposed to aerosols during maintenance of a cooling tower at a waste processing plant. This report documents the first known occupation-related outbreak of Legionella pneumonia in Japan. 相似文献
117.
Mari Terada Satoshi Kutsuna Tomiteru Togano Sho Saito Noriko Kinoshita Yumiko Shimanishi Tetsuya Suzuki Yusuke Miyazato Makoto Inada Takahito Nakamoto Hidetoshi Nomoto Satoshi Ide Mitsuhiro Sato Kenji Maeda Akihiro Matsunaga Masahiro Satake Keiji Matsubayashi Hirokazu Tsuno Makiko Kojima Madoka Kuramistu Kenta Tezuka Emi Ikebe Kazu Okuma Isao Hamaguchi Katsuyuki Shiratori Motohiko Sato Yuiko Kawakami Kumi Inaba Saori Igarashi Reina Yamauchi Mina Matsumura Keiko Ishimaru Bijuan Zhang Chika Kuge Maiko Ishihara Miho Gouda Keiko Tanaka Yukihito Ishizaka Norio Ohmagari 《Transfusion》2021,61(7):1998-2007
118.
Yuji Miyazaki Yukiho Takenaka Yasutaka Noda Nobuyuki Kawai Takanori Yoshikawa Takahito Wakamiya Isao Hara Tetsuo Sonomura 《Brachytherapy》2021,20(4):866-872
PurposeThe purpose of the study was to elucidate the usefulness of a dose evaluation method for reducing late genitourinary (GU) toxicity in high-dose-rate brachytherapy (HDR-BT) of prostate cancer.Methods and MaterialsGU toxicity was scored in accordance with the Common Terminology Criteria for Adverse Events version 4.0. The prostatic urethra was divided into three segments (base = B, midgland = M, apex = A), which were subclassified into seven subgroups (B, M, A, BM, BA, MA, BMA) using a D10% color map of the urethra. Significance testing was conducted on urethral D0.1% and D10% among the seven subgroups. Grade < 2 GU toxicity was also implemented.ResultsData of 174 patients with localized prostate cancer treated with HDR-BT combined with external beam radiotherapy between November 2011 and July 2014 were analyzed retrospectively. Median age was 74 (53–84) years, and median followup period was 44 (6–69) months. The number of Grade < 2 and Grade ≥ 2 toxicity was significantly different in the M subgroup than in the other subgroups (p < 0.05), suggesting increased radioresistance in the midgland urethra.ConclusionsA high-dose-area evaluation method using a urethral D10% color map may be helpful in reducing late GU toxicity in HDR-BT for prostate cancer. 相似文献
119.
Isao Ohsawa Daisuke Honda Yusuke Suzuki Tomoo Fukuda Keisuke Kohga Eishin Morita Shinichi Moriwaki Osamu Ishikawa Yoshihiro Sasaki Masaki Tago Greg Chittick Melanie Cornpropst Sharon C. Murray Sylvia M. Dobo Eniko Nagy Sharon Van Dyke Lacy Reese Jessica M. Best Heather Iocca Phil Collis William P. Sheridan Michihiro Hide 《Allergy》2021,76(6):1789-1799
120.