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41.
42.
Yo Kobayashi Ryutaro Hamano Hiroki Watanabe Jaesung Hong Kazutaka Toyoda Makoto Hashizume Masakatsu G. Fujie 《Medical engineering & physics》2013,35(5):684-689
Central venous catheterization involves venous puncture and catheter insertion for transfusions. Quantitative conditions that facilitate insertion of the needle, such as the angle and velocity of insertion, have not been clarified. We previously developed a robotic system for guiding the needle along a specified puncture path with high precision and are currently implementing a hardware design for a robotic system to assist in blood vessel puncture. In this study, we proposed the insertion angle and velocity for stopping the needle in a blood vessel, assuming that a robotic system such as ours is used during the procedure. We inserted a needle into a segment of porcine jugular vein and obtained the puncture reaction force. Evaluation indices were the magnitude of the sudden decrease in reaction force at the point at which the needle advances and the length of time that the needle is present within the vein. Results indicated that the conditions under which it was easiest to stop the needle inside the vein were an insertion angle range of 10–20 and an insertion velocity of 3 mm/s. 相似文献
43.
Oikawa Y Kirigaya H Aizawa T Nagashima K Yajima J Ishimura K Hara H Sahara M Iinuma H Fu LT 《The American journal of cardiology》2002,89(5):505-510
The main mechanism of restenosis after directional coronary atherectomy (DCA) remains obscure. We investigated mechanisms of restenosis after DCA in different coronary artery remodeling patterns. DCA was performed in 51 de novo lesions. The lesions were evaluated by intravascular ultrasound (IVUS) before, immediately after, and 6 months after the procedure. According to the IVUS findings before DCA, we classified the lesions into the following 3 groups: (1) positive (n = 10), (2) intermediate (n = 25), and (3) negative (n = 16) remodeling. We measured lumen area, vessel area, and plaque area using IVUS before DCA, immediately after DCA, and at follow-up. Lumen area increase after DCA was mainly due to plaque area reduction in the positive and intermediate remodeling groups (90 plus minus 15% and 80 plus minus 25% increase in lumen area, respectively), whereas that in the negative remodeling group was due to both plaque area reduction (57 plus minus 22% increase in lumen area) and vessel area enlargement (43 plus minus 33% increase in lumen area). The plaque area increase correlated strongly with late lumen area loss in the positive and intermediate remodeling groups (r = 0.884, p <0.001; r = 0.626, p <0.001, respectively), but the decrease in vessel area was not correlated with lumen area loss. In contrast, both an increase in plaque area and a decrease in vessel area were correlated with late lumen area loss (r = 0.632, p = 0.009; r = 0.515, p = 0.041) in the negative remodeling group. Coronary artery restenosis after atherectomy was primarily due to an increase in plaque in the positive and/or intermediate remodeling groups. However, in the negative remodeling group, late lumen loss might have been caused by both an increase in plaque and vessel shrinkage. 相似文献
44.
Takeshi Imura Yuki Nagasawa Tetsuji Inagawa Naoki Imada Hiroaki Izumi Katsuya Emoto Itaru Tani Hiroyuki Yamasaki Yuichiro Ota Shuichi Oki Tadanori Maeda Osamu Araki 《Journal of Physical Therapy Science》2015,27(5):1383-1386
[Purpose] The efficacy of diffusion tensor imaging in the prediction of motor outcomes
and activities of daily living function remains unclear. We evaluated the most appropriate
diffusion tensor parameters and methodology to determine whether the region of interest-
or tractography-based method was more useful for predicting motor outcomes and activities
of daily living function in stroke patients. [Subjects and Methods] Diffusion tensor
imaging data within 10 days after stroke onset were collected and analyzed for 25
patients. The corticospinal tract was analyzed. Fractional anisotropy, number of fibers,
and apparent diffusion coefficient were used as diffusion tensor parameters. Motor
outcomes and activities of daily living function were evaluated on the same day as
diffusion tensor imaging and at 1 month post-onset. [Results] The fractional anisotropy
value of the affected corticospinal tract significantly correlated with the motor outcome
and activities of daily living function within 10 days post-onset and at 1 month
post-onset. Tthere were no significant correlations between other diffusion tensor
parameters and motor outcomes or activities of daily living function. [Conclusion] The
fractional anisotropy value of the affected corticospinal tract obtained using the
tractography-based method was useful for predicting motor outcomes and activities of daily
living function in stroke patients.Key words: Stroke, Diffusion tensor tractography, Activities of daily living function 相似文献
45.
Tadanori Aizawa MD Ken Ogasawara MD Fumitaka Nakamura MD Akira Hirosaka MD Tohru Sakuma MD Kazuyuki Nagashima MD Kazuzo Kato MD 《The American journal of cardiology》1989,63(21):J75-J79
In patients in whom dynamic coronary obstruction plays a predominant role in the pathogenesis of angina pectoris, dilatation of large coronary arteries and relief of coronary spasm account for the main mechanism of action of antianginal drugs. In this study, the acute vasodilating effects of nicorandil, a newly developed antianginal drug, were assessed in 10 patients who had spontaneous and ergonovine-evoked coronary spasms. The prompt, complete relief of both spontaneous and evoked coronary spasms was obtained in all of 10 patients with nicorandil. The coronary spasmolytic effect of nicorandil in the present series is thus considered to be beneficial to the treatment of coronary spasm. 相似文献
46.
47.
Case series of 17 patients with cholangiocarcinoma among young adult workers of a printing company in Japan 下载免费PDF全文
Shoji Kubo Yasuni Nakanuma Shigekazu Takemura Chikaharu Sakata Yorihisa Urata Akinori Nozawa Takayoshi Nishioka Masahiko Kinoshita Genya Hamano Hiroaki Terajima Gorou Tachiyama Yuji Matsumura Terumasa Yamada Hiromu Tanaka Shoji Nakamori Akira Arimoto Norifumi Kawada Masahiro Fujikawa Hiromitsu Fujishima Yasuhiko Sugawara Shogo Tanaka Hideyoshi Toyokawa Yuko Kuwae Masahiko Ohsawa Shinichiro Uehara Kyoko Kogawa Sato Tomoshige Hayashi Ginji Endo 《Journal of hepato-biliary-pancreatic sciences》2014,21(7):479-488
48.
49.
Masanori Kawakami Shigeki Morita Mitsuhiro Sunohara Yosuke Amano Rie Ishikawa Kousuke Watanabe Emi Hamano Nobuya Ohishi Jun Nakajima Yutaka Yatomi Takahide Nagase Masashi Fukayama Daiya Takai 《International journal of clinical and experimental pathology》2013,6(4):598-612
Here, we show that overexpression of fer tyrosine kinase (FER), a non-receptor tyrosine kinase, predicts poor postoperative outcome and might be involved in cancer-cell survival in non-small cell lung cancer (NSCLC). Systematic screening using in silico analyses and quantitative RT-PCR revealed that FER was overexpressed in about 10% of NSCLC patients. Evaluation of FER expression using immunohistochemistry (IHC) on tissue microarrays was consistent with the mRNA level detected using quantitative RT-PCR. In analyses of 135 NSCLC patients who had undergone potential curative resection, we found that FER overexpression detected using IHC had no association with clinicopathological features such as age, sex, smoking history, histological type, disease stage, T factor, N factor, adjuvant chemotherapy history, or EGFR mutation, but was correlated with poor postoperative survival periods. A multivariate Cox regression analysis showed that this prognostic impact was independent of other clinicopathological features. In functional analyses of FER in vitro, FER exhibited a transforming activity, suggesting that it possesses oncogenic functions. We also found that human lung cancer NCI-H661 cells, which exhibited FER-outlier expression, were led to apoptosis by the knockdown of FER using RNA interference. FER overexpression might serve as a prognostic biomarker and be involved in cancer-cell survival in NSCLC. 相似文献