全文获取类型
收费全文 | 15485篇 |
免费 | 1206篇 |
国内免费 | 54篇 |
专业分类
耳鼻咽喉 | 209篇 |
儿科学 | 330篇 |
妇产科学 | 216篇 |
基础医学 | 1912篇 |
口腔科学 | 433篇 |
临床医学 | 1536篇 |
内科学 | 3599篇 |
皮肤病学 | 187篇 |
神经病学 | 1219篇 |
特种医学 | 644篇 |
外科学 | 2303篇 |
综合类 | 317篇 |
一般理论 | 16篇 |
预防医学 | 1161篇 |
眼科学 | 592篇 |
药学 | 1051篇 |
中国医学 | 38篇 |
肿瘤学 | 982篇 |
出版年
2022年 | 82篇 |
2021年 | 192篇 |
2020年 | 97篇 |
2019年 | 191篇 |
2018年 | 214篇 |
2017年 | 172篇 |
2016年 | 207篇 |
2015年 | 250篇 |
2014年 | 401篇 |
2013年 | 667篇 |
2012年 | 829篇 |
2011年 | 905篇 |
2010年 | 494篇 |
2009年 | 477篇 |
2008年 | 882篇 |
2007年 | 1016篇 |
2006年 | 1032篇 |
2005年 | 991篇 |
2004年 | 1057篇 |
2003年 | 976篇 |
2002年 | 975篇 |
2001年 | 138篇 |
2000年 | 97篇 |
1999年 | 171篇 |
1998年 | 231篇 |
1997年 | 208篇 |
1996年 | 183篇 |
1995年 | 192篇 |
1994年 | 145篇 |
1993年 | 150篇 |
1992年 | 88篇 |
1991年 | 94篇 |
1990年 | 100篇 |
1989年 | 97篇 |
1988年 | 100篇 |
1987年 | 81篇 |
1986年 | 87篇 |
1985年 | 110篇 |
1984年 | 170篇 |
1983年 | 148篇 |
1982年 | 218篇 |
1981年 | 219篇 |
1980年 | 170篇 |
1979年 | 94篇 |
1978年 | 119篇 |
1977年 | 145篇 |
1976年 | 140篇 |
1975年 | 126篇 |
1974年 | 98篇 |
1973年 | 90篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Lopata AL Jeebhay MF Reese G Fernandes J Swoboda I Robins TG Lehrer SB 《International archives of allergy and immunology》2005,138(1):21-28
BACKGROUND: Aerosolization of fish proteins during seafood processing has been identified as a potential route for allergic sensitization and occupational asthma among workers involved in high-risk activities. The aim of this study was to develop immunological assays for the quantification of aerosolized fish antigens in a fish-processing factory. METHODS: Polyclonal antibodies to the main fish species processed in the factory (anchovy and pilchard) were generated in rabbits and compared by ELISA inhibition assay and immunoblotting. These antisera were utilized to develop ELISA assays for the detection of fish antigens. The ELISA inhibition assays were evaluated by analyzing environmental air samples collected from three areas in a fish-processing factory: pilchard canning, fish meal production and lobster processing. RESULTS: By immunoblotting, the rabbit polyclonal antibodies demonstrated IgG antibody binding patterns comparable with IgE antibodies of fish-sensitized patients, particularly in regard to the major fish allergens parvalbumins. The sensitivity of the fish-specific ELISA assays developed was 0.5 microg/ml. The ELISA inhibition assays were able to differentiate between the two different fish species of interest but did not recognize a crustacean species. Notable differences in exposure levels to canned pilchard and anchovy antigens were demonstrated in the three different working areas of the factory, with assays having a detection limit as low as 105 ng/m(3). CONCLUSION: These ELISA-based assays are sensitive and specific to quantify differential exposure levels to fish antigens produced during fish processing, making it possible to investigate exposure-disease response relationships among workers in this industry. 相似文献
62.
Rohit Bhargava William L Gerald Allan R Li Qiulu Pan Priti Lal Marc Ladanyi Beiyun Chen 《Modern pathology》2005,18(8):1027-1033
The human epidermal growth factor receptor (HER) family of receptor tyrosine kinase has been extensively studied in breast cancer; however, systematic studies of EGFR gene amplification and protein overexpression in breast carcinoma are lacking. We studied EGFR gene amplification by chromogenic in situ hybridization (CISH) and protein expression by immunohistochemistry in 175 breast carcinomas, using tissue microarrays. Tumors with >5 EGFR gene copies per nucleus were interpreted as positive for gene amplification. Protein overexpression was scored according to standardized criteria originally developed for HER-2. EGFR mRNA levels, as measured by Affymetrix U133 Gene Chip microarray hybridization, were available in 63 of these tumors. HER-2 gene amplification by fluorescence in situ hybridization (FISH) and protein overexpression by immunohistochemistry were also studied. EGFR gene amplification (copy number range: 7-18; median: 12) was detected in 11/175 (6%) tumors, and protein overexpression was found in 13/175 (7%) tumors. Of the 11 tumors, 10 (91%) with gene amplification also showed EGFR protein overexpression (2+ or 3+ by immunohistochemistry). The EGFR mRNA level, based on Affymetrix U133 chip hybridization data, was increased relative to other breast cancer samples in three of the five tumors showing gene amplification. Exons 19 and 21 of EGFR, the sites of hotspot mutations in lung adenocarcinomas, were screened in the 11 EGFR-amplified tumors but no mutations were found. Three of these 11 tumors also showed HER-2 overexpression and gene amplification. Approximately 6% of breast carcinomas show EGFR amplification with EGFR protein overexpression and may be candidates for trials of EGFR-targeted antibodies or small inhibitory molecules. 相似文献
63.
64.
Immunological Studies on the Envelope Component of Venezuelan Equine Encephalomyelitis Virus 总被引:5,自引:1,他引:5 下载免费PDF全文
Treatment of purified Venezuelan equine encephalomyelitis virus with the nonionic detergent Triton X-100 permitted spearation of the envelope from the core component. The isolated envelope was a noninfectious immunogen which reacted in hemagglutination, hemagglutination inhibition, complement fixation, and neutralization serological reactions. 相似文献
65.
Susan M Abdel-Rahman Nasreen Talib Ada Solidar Amy Jo Nopper Gerald J Wyckoff 《Medical mycology》2008,46(3):217-223
Trichophyton tonsurans infections occur in various host populations, on various body sites and with varying degrees of inflammation. This investigation was undertaken to determine whether fungal factors could explain the degree of severity in clinical symptomatology among infected children. Otherwise healthy children (n=54) presenting with tinea capitis were enrolled in this study. A thorough history was performed, the extent and severity of infection graded and a fungal specimen collected from each child. Strain type was determined by genotyping for 11 sequence variations in the rDNA and ALP1 loci. Secreted protease activity was quantitated after 5 days of growth in aqueous medium. Forty participants were evaluable. Infection duration ranged from 1 day to 3 years and clinical severity score (CSS) from 4-19. Seventeen unique fungal genotypes were present. Keratinase, collagenase and elastase activity varied 32.7-fold, 64.9-fold and 303.3-fold, respectively. A significant association was observed between genotype and disease severity with the rDNA sequence variations accounting for over 50% of the variation observed in CSS (r2=0.539; P<0.001). Phylogenetic analyses appear to suggest that the ancestral strain types of T. tonsurans cause more severe disease. These observations are consistent with reports that recently diverge anthropophilies are associated with diminished inflammatory involvement. 相似文献
66.
Gerald Batist Raymond W. Klecker Jr. Hiremagalur N. Jayaram Jean F. Jenkins John Grygiel Daniel C. Ihde Joyce L. Eddy Robert L. Fine Ian G. Kerr Jerry M. Collins 《Investigational new drugs》1985,3(4):349-355
Summary Tiazofurin (2--D-ribofuranosylthiazole-4-carboxamide, TCAR) is a synthetic C-nucleoside that demonstrated significant in vivo activity against a variety of animal tumors as well as in vitro activity against human tumor-derived cell lines. Thirteen patients were treated with TCAR administered as a 5-day continuous infusion in this Phase I trial. Seventeen complete cycles were administered in three dose levels ranging from 550 to 1450 mg/M2. Dose-limiting toxicities were myelosuppression and neurotoxicity including severe lethargy. Other toxicities including superficial skin peeling, myalgias, and tearing were seen at all doses. One patient had chest pain on day 4 resulting in stopping the drug, however, there was no evidence of cardiac or pericardial disease. Uric acid levels rose within one day in the absence of allopurinol treatment. There were no treatment related deaths. HPLC measurement of drug levels demonstrated steady-state plasma levels during the infusion, and a half-life following the infusion of 7.7 ± 0.6 hours. Minor abnormalities in renal function were associated with dramatic changes in pharmacokinetics and toxicity. No clinical responses were observed in this trial.Abbreviations TCAR
Tiazofurin
- HPLC
High performance liquid chromatography
- IMPD
Inosine monophosphate dehydrogenase
- WBC
white blood cell
- CPK
creatine phosphokinase
- Css
steady-state concentration 相似文献
67.
68.
Summary The repair of all hypospadias in one stage represents state of the art in virtually all instances. Implicit in the repair of hypospadias is the correction of chordee, the construction of the neourethra such that the meatus is located on the tip of the glans, and the creation of a penis which is cosmetically appropriate. Described in this paper are most of the currently employed methods utilized for the repair of hypospadias in a single stage. The techniques described herein, in skilled hands, yield good results in 85–90% of cases. Repairs of hypospadias which have been designed and which are recommended for the occasional operator have no place in today's surgical therapy. 相似文献
69.
70.
Magdalena Hoffmann Christine Maria Schwarz Stefan Fürst Christina Starchl Elisabeth Lobmeyr Gerald Sendlhofer Marie-Madlen Jeitziner 《Nutrients》2021,13(1)
Critically ill patients in the intensive care unit (ICU) have a high risk of developing malnutrition, and this is associated with poorer clinical outcomes. In clinical practice, nutrition, including enteral nutrition (EN), is often not prioritized. Resulting from this, risks and safety issues for patients and healthcare professionals can emerge. The aim of this literature review, inspired by the Rapid Review Guidebook by Dobbins, 2017, was to identify risks and safety issues for patient safety in the management of EN in critically ill patients in the ICU. Three databases were used to identify studies between 2009 and 2020. We assessed 3495 studies for eligibility and included 62 in our narrative synthesis. Several risks and problems were identified: No use of clinical assessment or screening nutrition assessment, inadequate tube management, missing energy target, missing a nutritionist, bad hygiene and handling, wrong time management and speed, nutritional interruptions, wrong body position, gastrointestinal complication and infections, missing or not using guidelines, understaffing, and lack of education. Raising awareness of these risks is a central aspect in patient safety in ICU. Clinical experts can use a checklist with 12 identified top risks and the recommendations drawn up to carry out their own risk analysis in clinical practice. 相似文献