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61.
Noguchi Y Matsui K Imura H Kiyota M Fukui T 《Journal of general internal medicine》2002,17(11):848-853
OBJECTIVE: To explore the diagnostic thinking process of medical students. SUBJECTS AND METHODS: Two hundred twenty-four medical students were presented with 3 clinical scenarios corresponding to high, low, and intermediate pre-test probability of coronary artery disease. Estimates of test characteristics of the exercise stress test, and pre-test and post-test probability for each scenario were elicited from the students (intuitive estimates) and from the literature (reference estimates). Post-test probabilities were calculated using Bayes' theorem based upon the intuitive estimates (Bayesian estimates of post-test probability) and upon the reference estimates (reference estimates of post-test probability). The differences between the reference estimates and the intuitive estimates, and between Bayesian estimates and the intuitive estimates were used for assessing knowledge of test characteristics, and ability of estimating pre-test and post-test probability of disease. RESULTS: Medical students could not rule out disease in low or intermediate pre-test probability settings, mainly because of poor pre-test estimates of disease probability. They were also easily confused by test results that differed from their anticipated results, probably because of their inaptitude in applying Bayes' theorem to real clinical situations. These diagnostic thinking patterns account for medical students or novice physicians repeating unnecessary examinations. CONCLUSIONS: Medical students' diagnostic ability may be enhanced by the following educational strategies: 1) emphasizing the importance of ruling out disease in clinical practice, 2) training in the estimation of pre-test disease probability based upon history and physical examination, and 3) incorporation of the Bayesian probabilistic thinking and its application to real clinical situations. 相似文献
62.
Atrial natriuretic polypeptide is removed by the lungs and released into the left atrium as well as the right atrium in humans 总被引:1,自引:0,他引:1
K Obata H Yasue K Okumura K Matsuyama H Ogawa M Kurose Y Saito K Nakao H Imura M Nobuyoshi 《Journal of the American College of Cardiology》1990,15(7):1537-1543
To examine the sites of release and removal of plasma atrial natriuretic polypeptide plasma levels in the femoral vein, right atrium, pulmonary artery, pulmonary capillary bed, left atrium and aortic root were measured in 11 control subjects and 22 patients with mitral stenosis. Mean plasma natriuretic polypeptide levels in the femoral vein, right atrium, pulmonary artery, pulmonary capillary bed, left atrium and aortic root were, respectively, 64 +/- 29, 124 +/- 72, 103 +/- 44, 83 +/- 30, 106 +/- 46 and 101 +/- 35 pg/ml in the control subjects and 321 +/- 170, 500 +/- 234, 458 +/- 266, 356 +/- 209, 434 +/- 222 and 432 +/- 217 pg/ml in the patients with mitral stenosis. In both the control subjects and the patients with mitral stenosis, there was a significant increase between the femoral vein and the right atrium and between the pulmonary capillary bed and the left atrium and a significant decrease between the pulmonary artery and the pulmonary capillary bed. Blood samples were also taken simultaneously from the pulmonary vein and the pulmonary capillary bed, as well as from the pulmonary artery and the left atrium, in 25 patients (11 control subjects, 5 patients with mitral stenosis and 9 patients with atrial septal defect). There was no difference in plasma atrial natriuretic polypeptide levels between the pulmonary capillary bed and the pulmonary vein in these 25 patients. It is concluded that atrial natriuretic polypeptide 1) is released into the left as well as the right atrium, and 2) is removed by the lungs. 相似文献
63.
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
64.
A Suzuki T Takahashi K Nakamura R Tsuyuoka Y Okuno T Enomoto M Fukumoto H Imura 《Blood》1992,80(8):2052-2059
We investigated the cause of thrombocytosis in 14 patients with tumors producing colony-stimulating factor (CSF). Of the 14 patients, 10 had tumors producing granulocyte-CSF (G-CSF) and 4 had tumors producing granulocyte-macrophage--CSF (GM-CSF). Thrombocytosis of greater than 400 x 10(9)/L was noted in 8 of 10 patients with G-CSF-producing tumors and all 4 patients with GM-CSF-producing tumors. Median peak platelet counts were, respectively, 511 x 10(9)/L (range, 384 to 694 x 10(9)/L) and 579 x 10(9)/L (range, 526 to 910 x 10(9)/L) in patients with tumors producing G-CSF and GM-CSF. In most patients, thrombocytosis declined towards the terminal stage. High interleukin-1 (IL-1) and IL-6 levels were found in addition to CSFs in the plasma or culture supernatants of tumor cells obtained from most patients. In patients with GM-CSF-producing tumors, these specimens had megakaryocyte-CSF (Meg-CSF) activity, which was abolished by anti-GM-CSF antibody. These specimens also had megakaryocyte potentiating (Meg-Pot) activity attributable to both GM-CSF and IL-6. In patients with G-CSF-producing tumors, only Meg-Pot activity due to IL-6 was detected. These results indicate that the thrombocytosis in GM-CSF-producing tumors was caused by both the Meg-CSF activity of GM-CSF and the Meg-Pot activity of IL-6 plus GM-CSF, while that in G-CSF-producing tumors was due to the Meg-Pot activity of IL-6. 相似文献
65.
Shiozawa K Tanaka Y Yoshihara R Imura S Murata M Yamane T Miura Y Hashiramoto A Shiozawa S 《Modern rheumatology / the Japan Rheumatism Association》2005,15(6):405-409
Methotrexate (MTX) is the first-choice drug for rheumatoid arthritis (RA); however, the pharmacodynamics of MTX in Japanese
patients with RA treated legitimately according to the government recommended dosage, 6 mg per week, are unknown. Methotrexate
and its metabolite, 7-hydroxy MTX (7-OH MTX), were measured in sera of 16 outpatients with active RA in the first week of
MTX treatment and 4–12 weeks after the introduction at 0, 1, 2, 4, and 8 h after administration of the first and the third
2-mg capsule, followed by sampling at 48, 96, and 168 h. The mean maximal serum drug concentration (mean Cmax) of MTX attained at 1–2 h after ingestion of the first capsule was 0.215 and 0.252 μM, respectively, in the first and the
follow-up week. The mean Cmax after ingestion of the third capsule was 0.223 μM and 0.357 μM. The mean Cmax of 7-OH MTX was 0.0334 and 0.0289 μM for the first capsule, and 0.0495 and 0.0672 μM for the third capsule. The results indicate
that MTX does not accumulate or deposit in the body of Japanese patients with RA when treated with 6 mg per week, and pharmacodynamics
of MTX are comparable to those in overseas patients treated with 7.5 mg per week. 相似文献
66.
67.
Distinctive population of Gfap‐expressing neural progenitors arising around the dentate notch migrate and form the granule cell layer in the developing hippocampus
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Tatsunori Seki Toru Sato Keiko Toda Noriko Osumi Tetsuya Imura Seiji Shioda 《The Journal of comparative neurology》2014,522(2):261-283
In the adult hippocampus, granule cells continue to be generated from astrocyte‐like progenitors expressing glial fibrillary acidic protein (GFAP) that differ from embryonic neocortical progenitors. However, during the embryonic period, dentate granule neurons and neocortical pyramidal neurons are derived from the ventricular zone (VZ) of the pallium. Our question is when do GFAP+ progenitors of granule neurons appear in the developing hippocampus during the embryonic period, and how do they form the granule cell layer. The present analysis using Gfap‐GFP transgenic mice shows that the GFP+ distinct cell population first appears in the VZ of the medial pallium at the dorsal edge of the fimbria on embryonic day 13.5. During the perinatal period, they form a migratory stream from the VZ to the developing dentate gyrus, and establish the germinal zones in the migratory stream, and the marginal and hilar regions in the developing dentate gyrus. GFP+ cells in these regions were positive for Sox2 and Ki67, but negative for BLBP. GFP+ cells with Neurogenin2 expression were largely distributed in the VZ, whereas GFP+ cells with Tbr2 and NeuroD expressions were seen in the migratory stream and developing dentate gyrus. Prox1‐expressing GFP+ cells were restricted to the developing dentate gyrus. These results suggest that distinctive Gfap‐expressing progenitors arising around the dentate notch form germinal regions in the migratory stream and the developing dentate gyrus where they differentiate into granule neurons, indicating that distinct astrocyte‐like neural progenitors continue to generate granule neurons, from the beginning of dentate development and throughout life. J. Comp. Neurol. 522:261–283, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
68.
Chown SL Huiskes AH Gremmen NJ Lee JE Terauds A Crosbie K Frenot Y Hughes KA Imura S Kiefer K Lebouvier M Raymond B Tsujimoto M Ware C Van de Vijver B Bergstrom DM 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(13):4938-4943
Invasive alien species are among the primary causes of biodiversity change globally, with the risks thereof broadly understood for most regions of the world. They are similarly thought to be among the most significant conservation threats to Antarctica, especially as climate change proceeds in the region. However, no comprehensive, continent-wide evaluation of the risks to Antarctica posed by such species has been undertaken. Here we do so by sampling, identifying, and mapping the vascular plant propagules carried by all categories of visitors to Antarctica during the International Polar Year''s first season (2007–2008) and assessing propagule establishment likelihood based on their identity and origins and on spatial variation in Antarctica''s climate. For an evaluation of the situation in 2100, we use modeled climates based on the Intergovernmental Panel on Climate Change''s Special Report on Emissions Scenarios Scenario A1B [Nakićenović N, Swart R, eds (2000) Special Report on Emissions Scenarios: A Special Report of Working Group III of the Intergovernmental Panel on Climate Change (Cambridge University Press, Cambridge, UK)]. Visitors carrying seeds average 9.5 seeds per person, although as vectors, scientists carry greater propagule loads than tourists. Annual tourist numbers (∼33,054) are higher than those of scientists (∼7,085), thus tempering these differences in propagule load. Alien species establishment is currently most likely for the Western Antarctic Peninsula. Recent founder populations of several alien species in this area corroborate these findings. With climate change, risks will grow in the Antarctic Peninsula, Ross Sea, and East Antarctic coastal regions. Our evidence-based assessment demonstrates which parts of Antarctica are at growing risk from alien species that may become invasive and provides the means to mitigate this threat now and into the future as the continent''s climate changes. 相似文献
69.
Iwao Sato Kosuke Imura Yoko Miwa Shunji Yoshida Masataka Sunohara 《Journal of cranio-maxillo-facial surgery》2012,40(8):e249-e252
BackgroundSubstance P (SP) and calcitonin gene-related peptide (CGRP) are released by the nociceptive sensory nerve and are involved in blood flow, pain and inflammation in the nasal mucosa. The purpose of this study was to assess the distribution of the SP and CGRP nerve fibres related to blood supply within human Schneiderian membrane of the maxillary sinus (MS).Material and methodsIn this study, the MS from Japanese cadavers was examined by whole-mount immunohistochemistry. Human male cadavers (ranging in age from 80 to 90 years) were used in this study.ResultsSP- and CGRP-positive fibres were found around large vessels of the medialis superior alveolar branches and also within the floor region of the MS. The floor region of the MS was composed of complex branches of these fibres.ConclusionOur results give useful information for surgical sinus floor elevation in this region of the MS. These anatomical features may assist in the execution of a successful surgical procedure. 相似文献
70.
Kajiume T Sera Y Kawahara Y Matsumoto M Fukazawa T Imura T Yuge L Kobayashi M 《Experimental hematology》2012,40(9):751-760.e1
The Polycomb-group complex is a chromatin regulatory factor that is classified into two different complexes: Polycomb repressive complex 1 and 2. Components of Polycomb repressive complex 1 are involved in the self-renewal of hematopoietic stem cells. Bmi1, one of these components, maintains the immaturity of neural and cancer stem cells as well as that of hematopoietic stem cells. We constructed recombinant protein transduction domain (PTD)-Polycomb proteins and transduced them into murine bone marrow (BM) cells. We designed and fused the PTD-protein transduction domain to three proteins (i.e., green fluorescent protein, Bmi1, and Mel18). Murine BM cells were incubated for 48 h and each PTD-Polycomb protein was added. Then, we analyzed the function of hematopoiesis using the colony assay and transplantation. BM cells exposed to PTD-Bmi1 showed an increased number of colonies. In contrast, BM cells exposed to PTD-Mel18 or to both proteins showed a decreased number of colonies. Hematopoietic cells derived from PTD-Bmi1-transduced BM cells were significantly increased in the peripheral blood at 6 weeks after transplantation. Moreover, 80% of mice transplanted with PTD-Bmi1-transduced BM cells died at 8 to 24 weeks after transplantation. However, only a few early deaths were observed in the mice transplanted with BM cells exposed to both PTD-Bmi1 and PTD-Mel18. We expect that hematopoietic stem cells could proliferate after transduction with PTD-Bmi1, but this may generate undesirable effects, e.g., tumorigenesis. Thus, Bmi1 and Mel18 have opposing functions and are present in distinct complexes. 相似文献