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131.
Present 3-D stereology techniques use fixed grid sampling where the sampling grid of test points is randomly placed in 3-D. In order to increase randomness of sampling, in this paper we propose random grid sampling scheme where grid sections are placed randomly over 2-D cross-sections. A random grid sampler has superior efficiency and accuracy compared with fixed grid sampling. Using MR head scans we demonstrate the use of random grid sampling in volumetry of structures in 3-D biomedical images. 相似文献
132.
A rapid, sensitive and robust immunoassay based on a commercial surface plasmon resonance (SPR) instrument (Biacore X) was developed for the detection of ricin in environmental samples. A total of 10 monoclonal antibodies were evaluated for their ability to recognise both a commercial ricin and horticultural ricin variants extracted from six different cultivars of Ricinus communis. Two suitable antibodies (7G12 and TFTA) were identified because of their strong affinity to all six ricin variants. The antibody 7G12 was used as the capture ligand in the SPR system. The assay was linear over a wide range of ricin concentrations (up to at least 750ng/ml) with a limit of detection of 0.5ng/ml. The assay was highly reproducible (coefficient of variation was less than 5%), and was able to detect all six ricin variants and environmental samples. 相似文献
133.
An Audit of medical thoracoscopy and talc poudrage for pneumothorax prevention in advanced COPD 总被引:3,自引:0,他引:3
OBJECTIVES: To prospectively study all patients with COPD and spontaneous pneumothorax (SP) who underwent thoracoscopic talc poudrage (TP) under local anesthesia to determine its efficacy and safety in recurrence prevention. METHODS: Data on clinical measurements, complications, duration of chest tube drainage, length of hospital stay, and outcome were collected. RESULTS: Forty-one patients (38 men and 3 women) with a mean (+/- SD) age of 70.7 +/- 7.2 years were treated. All patients had COPD, with a mean FEV(1) of 41 +/- 14% predicted. The majority of SPs measured 20 to 50% in size, and 34% were recurrent. Three grams of talc were insufflated into the pleural cavity without complications. Thirteen patients (32%) complained of pain, 5 (12%) developed fever, 27 (66%) had subcutaneous emphysema, and 7 (17%) had prolonged air leaks. Postoperative chest tube drainage and hospital stay were 4 and 5 days, respectively. Success was 95% after a median follow-up of 35 months. Four patients with FEV(1) of < 40% predicted died within 30 days of the procedure, yielding a mortality rate of 10%. FEV(1) (in liters), FEV(1) (in % predicted), and ischemic heart disease were risk factors that influenced early mortality. CONCLUSION: Thoracoscopic TP is effective for pneumothorax prevention and can be performed with acceptable mortality in patients with advanced COPD. 相似文献
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Eugene Teck‐Leong Ng Meng‐Kwoon Sim Weng‐Keong Loke 《Journal of applied toxicology : JAT》2011,31(6):568-578
The present study investigated the protective actions of des‐aspartate‐angiotensin I (DAA‐I) in mice that were intranasally administered 2‐chloroethyl ethyl sulfide (CEES), a half sulfur mustard. The protection was dose‐dependent, and an oral dose of 75 mg kg?1 per day administered 18 h post exposure and for the following 13 days, offered maximum protection that increased survival by a third. DAA‐I attenuated the early processes of inflammation seen in the CEES‐inoculated mice. DAA‐I attenuated (i) elevated pulmonary ROS, and gp91‐phox protein of NADPH oxidase, a non phagocytic enzyme that generates superoxide and subsequent ROS; (ii) intercellular adhesion molecule‐1 (ICAM‐1) that is involved in the extravasation of circulating leucocytes; and (iii) myeloperoxidase activity, which is a surrogate enzymatic measurement of neutrophil infiltration. These actions led to improved histological lung structures, and survival of type‐1 pneumocytes. The action of DAA‐I on animal survival was blocked by losartan, a selective angiotensin AT1 receptor blocker, indicting that the AT1 receptor mediates the protection. The presence of elevated PGE2 and PGI2 in lung supernatants of DAA‐I treated CEES‐inoculated mice indicates that the two prostaglandins are involved in signaling the protective actions of DAA‐I. This finding complements earlier studies showing that DAA‐I acts on an indomethacin‐sensitive angiotensin AT1 receptor. The findings of the present study are the first demonstration of an angiotensin peptide as an effective antidote for CEES intoxication. DAA‐I is also an effective therapeutic intervention against CEES that was instituted at 18 h post exposure, and challenges conventional assumptions of limited efficacy with delayed action against alkylating agents. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
136.
FS Ong H Vakil Y Xue JZ Kuo KH Shah RB Lee KE Bernstein DL Rimoin T Getzug K Das JL Deignan JI Rotter WW Grody 《Clinical genetics》2013,84(1):55-59
Familial Mediterranean fever (FMF), inherited in an autosomal recessive manner, is a systemic auto‐inflammatory disorder characterized by recurrent attacks of fever with peritonitis, pleuritis, synovitis and erysipeloid rash. The marenostrin‐encoding fever (MEFV) gene, located on chromosome 16p13.3, is the only gene in which mutations are currently known to cause FMF. To correlate specific genotypes with adverse phenotypes of affected populations residing in the Western United States, a retrospective case series review was conducted of all MEFV gene mutation testing completed at UCLA Clinical Molecular Diagnostic Laboratory between February 2002 and February 2012, followed by clinical chart review of all subjects who either have a single or double mutation. All 12 common mutations in the MEFV gene were analyzed and the M694V variant was found to be associated with an adverse FMF clinical outcome in the Armenian‐American population, manifested by earlier onset of disease, increased severity of disease, and renal amyloidosis. 相似文献
137.
HZ Chong SK Yeap A Rahmat AM Akim NB Alitheen F Othman CL Gwendoline-Ee 《BMC complementary and alternative medicine》2012,12(1):134
ABSTRACT: BACKGROUND: Our previous study had shown that P. amaryllifolius was able to selectively inhibit cell proliferation of hormone independent breast cancer cell line MDA-MB-231. To understand the mode of killing and mechanism of action for P. amaryllifolius, the ethanol extract was evaluated for their alteration of cell cycle progression, PS externalization, DNA fragmentation and expression of anti/pro-apoptotic related protein. RESULTS: Cell cycle progression analysis, Annexin V and Tunel assays suggested that IC50 of P. amaryllifolius ethanol extract induced G0/G1 cell cycle arrest, PS externalization and DNA fragmentation. On the other hand, ELISA for cytochrome c, caspase-3/7, 8 and 9 indicated that apoptosis was contributed by mitochondrial cytochrome c release via induction of caspase 3/7, 9, and p53 was associated with the suppression of XIAP in P. amaryllifolius treated MDA-MB-231 cells. CONCLUSION: Our findings suggest that P. amaryllifolius ethanol extract induced apoptosis on hormone independent breast cancer cell line MDA-MB-231. 相似文献
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139.
BackgroundWikipedia is one of the most accessed sources of health information online. The current English-language Wikipedia contains more than 28,000 articles pertaining to health.ObjectiveThe aim was to characterize individuals’ motivations for contributing to health content on the English-language Wikipedia.MethodsA set of health-related articles were randomly selected and recent contributors invited to complete an online questionnaire and follow-up interview (by Skype, by email, or face-to-face). Interviews were transcribed and analyzed using thematic analysis and a realist grounded theory approach.ResultsA total of 32 Wikipedians (31 men) completed the questionnaire and 17 were interviewed. Those completing the questionnaire had a mean age of 39 (range 12-59) years; 16 had a postgraduate qualification, 10 had or were currently studying for an undergraduate qualification, 3 had no more than secondary education, and 3 were still in secondary education. In all, 15 were currently working in a health-related field (primarily clinicians). The median period for which they have been an active editing Wikipedia was 3-5 years. Of this group, 12 were in the United States, 6 were in the United Kingdom, 4 were in Canada, and the remainder from another 8 countries. Two-thirds spoke more than 1 language and 90% (29/32) were also active contributors in domains other than health. Wikipedians in this study were identified as health professionals, professionals with specific health interests, students, and individuals with health problems. Based on the interviews, their motivations for editing health-related content were summarized in 5 strongly interrelated categories: education (learning about subjects by editing articles), help (wanting to improve and maintain Wikipedia), responsibility (responsibility, often a professional responsibility, to provide good quality health information to readers), fulfillment (editing Wikipedia as a fun, relaxing, engaging, and rewarding activity), and positive attitude to Wikipedia (belief in the value of Wikipedia). An additional factor, hostility (from other contributors), was identified that negatively affected Wikipedians’ motivations.ConclusionsContributions to Wikipedia’s health-related content in this study were made by both health specialists and laypeople of varying editorial skills. Their motivations for contributing stem from an inherent drive based on values, standards, and beliefs. It became apparent that the community who most actively monitor and edit health-related articles is very small. Although some contributors correspond to a model of “knowledge philanthropists,” others were focused on maintaining articles (improving spelling and grammar, organization, and handling vandalism). There is a need for more people to be involved in Wikipedia’s health-related content. 相似文献
140.