全文获取类型
收费全文 | 341篇 |
免费 | 32篇 |
国内免费 | 3篇 |
专业分类
儿科学 | 4篇 |
基础医学 | 54篇 |
临床医学 | 8篇 |
内科学 | 54篇 |
皮肤病学 | 1篇 |
特种医学 | 4篇 |
外科学 | 30篇 |
综合类 | 17篇 |
一般理论 | 1篇 |
预防医学 | 177篇 |
药学 | 15篇 |
中国医学 | 1篇 |
肿瘤学 | 10篇 |
出版年
2023年 | 4篇 |
2022年 | 27篇 |
2021年 | 24篇 |
2020年 | 15篇 |
2019年 | 29篇 |
2018年 | 20篇 |
2017年 | 26篇 |
2016年 | 25篇 |
2015年 | 19篇 |
2014年 | 31篇 |
2013年 | 25篇 |
2012年 | 15篇 |
2011年 | 16篇 |
2010年 | 10篇 |
2009年 | 10篇 |
2008年 | 11篇 |
2007年 | 11篇 |
2006年 | 10篇 |
2005年 | 7篇 |
2004年 | 9篇 |
2003年 | 6篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1984年 | 3篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有376条查询结果,搜索用时 31 毫秒
101.
Lizette O. Durand Patrick Glew Diane Gross Matthew Kasper Susan Trock Inkyu K. Kim Joseph S. Bresee Ruben Donis Timothy M. Uyeki Marc-Alain Widdowson Eduardo Azziz-Baumgartner 《Emerging infectious diseases》2015,21(2):202-208
Co-circulation of influenza A(H5N1) and seasonal influenza viruses among humans and animals could lead to co-infections, reassortment, and emergence of novel viruses with pandemic potential. We assessed the timing of subtype H5N1 outbreaks among poultry, human H5N1 cases, and human seasonal influenza in 8 countries that reported 97% of all human H5N1 cases and 90% of all poultry H5N1 outbreaks. In these countries, most outbreaks among poultry (7,001/11,331, 62%) and half of human cases (313/625, 50%) occurred during January–March. Human H5N1 cases occurred in 167 (45%) of 372 months during which outbreaks among poultry occurred, compared with 59 (10%) of 574 months that had no outbreaks among poultry. Human H5N1 cases also occurred in 59 (22%) of 267 months during seasonal influenza periods. To reduce risk for co-infection, surveillance and control of H5N1 should be enhanced during January–March, when H5N1 outbreaks typically occur and overlap with seasonal influenza virus circulation. 相似文献
102.
103.
Since 1997 the world has been facing the threat of a human influenza pandemic that may be caused by an avian virus and the poultry industry around the globe has been grappling with the highly pathogenic strain of avian influenza H5N1, or in more informal terms bird flu. The UK poultry industry has lived with and through this threat and its consequences since 2005. This study investigates knowledge claims about health, hygiene and biosecurity as tools to ward off the threat from this virus. It takes a semi-ethnographic and discourse analytic approach to analyse a small corpus of semi-structured interviews carried out in the wake of one of the most publicised outbreaks of H5N1 in Suffolk in 2007. It reveals that claims about what best to do to protect flocks against the risk of disease are divided along lines imposed on the one hand by the structure of the industry and on the other by more ‘tribal’ lines drawn by knowledge and belief systems about purity and dirt, health and hygiene. 相似文献
104.
105.
Eye and respiratory symptoms in poultry processing workers exposed to chlorine by-products 总被引:1,自引:0,他引:1
King BS Page EH Mueller CA Dollberg DD Gomez KE Warren AM 《American journal of industrial medicine》2006,49(2):119-126
BACKGROUND: CDC/NIOSH responded to a request to investigate complaints of eye and respiratory irritation among workers in a poultry processing facility's evisceration department. METHODS: Investigators administered symptom questionnaires and sampled for chlorine and chloramines. Spirometry was performed on workers before and after their work shift. RESULTS: Symptoms were significantly more prevalent in evisceration workers than in dark meat workers (a control group). Air concentrations of chloramine compounds (i.e., trichloramine and 'soluble chlorine') were significantly higher in the evisceration area than the dark meat area. Exposure levels were significantly higher for employees reporting various symptoms compared to employees not reporting those symptoms. Mean trichloramine exposure concentrations were significantly higher in workers with significant cross-shift declines in lung function; air concentrations of 'soluble chlorine' were higher as well, however, not significantly so. CONCLUSIONS: Results of this evaluation suggest a health hazard may exist from exposure to chloramines. 相似文献
106.
Gupta A Nelson JM Barrett TJ Tauxe RV Rossiter SP Friedman CR Joyce KW Smith KE Jones TF Hawkins MA Shiferaw B Beebe JL Vugia DJ Rabatsky-Ehr T Benson JA Root TP Angulo FJ;NARMS Working Group 《Emerging infectious diseases》2004,10(6):1102-1109
We summarize antimicrobial resistance surveillance data in human and chicken isolates of Campylobacter. Isolates were from a sentinel county study from 1989 through 1990 and from nine state health departments participating in National Antimicrobial Resistance Monitoring System for enteric bacteria (NARMS) from 1997 through 2001. None of the 297 C. jejuni or C. coli isolates tested from 1989 through 1990 was ciprofloxacin-resistant. From 1997 through 2001, a total of 1,553 human Campylobacter isolates were characterized: 1,471 (95%) were C. jejuni, 63 (4%) were C. coli, and 19 (1%) were other Campylobacter species. The prevalence of ciprofloxacin-resistant Campylobacter was 13% (28 of 217) in 1997 and 19% (75 of 384) in 2001; erythromycin resistance was 2% (4 of 217) in 1997 and 2% (8 of 384) in 2001. Ciprofloxacin-resistant Campylobacter was isolated from 10% of 180 chicken products purchased from grocery stores in three states in 1999. Ciprofloxacin resistance has emerged among Campylobacter since 1990 and has increased in prevalence since 1997. 相似文献
107.
Red meat consumption and risk of cancers of the proximal colon, distal colon and rectum: the Swedish Mammography Cohort 总被引:10,自引:0,他引:10
Larsson SC Rafter J Holmberg L Bergkvist L Wolk A 《International journal of cancer. Journal international du cancer》2005,113(5):829-834
Although there is considerable evidence that high consumption of red meat may increase the risk of colorectal cancer, data by subsite within the colon are sparse. The objective of our study was to prospectively examine whether the association of red meat consumption with cancer risk varies by subsite within the large bowel. We analyzed data from the Swedish Mammography Cohort of 61,433 women aged 40-75 years and free from diagnosed cancer at baseline in 1987-1990. Diet was assessed at baseline using a self-administered food-frequency questionnaire. Over a mean follow-up of 13.9 years, we identified 234 proximal colon cancers, 155 distal colon cancers and 230 rectal cancers. We observed a significant positive association between red meat consumption and risk of distal colon cancer (p for trend = 0.001) but not of cancers of the proximal colon (p for trend = 0.95) or rectum (p for trend = 0.32). The multivariate rate ratio for women who consumed 94 or more g/day of red meat compared to those who consumed less than 50 g/day was 2.22 (95% confidence interval [CI] 1.34-3.68) for distal colon, 1.03 (95% CI 0.67-1.60) for proximal colon and 1.28 (95% CI 0.83-1.98) for rectum. Although there was no association between consumption of fish and risk of cancer at any subsite, poultry consumption was weakly inversely related to risk of total colorectal cancer (p for trend = 0.04). These findings suggest that high consumption of red meat may substantially increase the risk of distal colon cancer. Future investigations on red meat and colorectal cancer risk should consider cancer subsites separately. 相似文献
108.
固相萃取高效液相色谱法同时测定禽畜组织中雌雄性激素残留的研究 总被引:10,自引:1,他引:10
目的:固相萃取高效液相色谱法同时测定禽畜组织中已烯雌酚(DES)、丙酸睾酮(TES)的残留量。方法:固相萃取小柱为AlltechExtract-cleancolumnsC18, 200mg/4 .0ml,洗脱液为甲醇;色谱柱为SUPELCODiscoveryC18 5μm250×4 .6mm,流动相为:甲醇∶水=85∶15(v/v),流速为1 0ml/min,二极管阵列检测器,检测波长为245nm。结果:该方法的线性范围为: 0 5 ~10 0μg/ml;标准曲线线性良好,其回归方程及相关系数r分别为已烯雌酚:Y=61 .31042X+2. 38615,r=0 99999;丙酸睾酮:Y=60. 42778X-0 20465,r=0 .99994。最低检出限分别为:已烯雌酚9. 5μg/kg;丙酸睾酮8 .4μg/kg;回收率在92% ~103% 之间,相对标准偏差小于1 .3%。结论:该方法操作简便、快捷,是禽畜类食品激素残留的快速而准确的检测方法。 相似文献
109.
ABSTRACTInfectious laryngotracheitis (ILT) is a highly contagious respiratory disease of chickens, pheasants, and peafowl. It is caused by the alpha herpesvirus, infectious laryngotracheitis virus (ILTV). Glycoprotein D (gD) of ILTV is immunogenic and helps in its binding to the susceptible host cell receptor. In the present study, a recombinant gD protein was expressed in a prokaryotic system to develop a single serum dilution ELISA. In addition, two immunogenic peptides, corresponding to regions 77–89 and 317–328, were identified in gD protein. The peptides were synthesized using solid-phase peptide synthesis, purified using reversed-phase HPLC, and characterized using mass spectrometry. The peptides displayed a good titre and were found to be promising antigens to coat the ELISA plate to detect the ILTV antibodies in the serum sample. The developed ELISA showed 96.9% sensitivity, 87.5% specificity, and 95.3% accuracy as compared to OIE referenced standard indirect ILTV ELISA (whole viral coated). The assay may not differentiate vaccinated from infected birds when the flocks are administered with live attenuated vaccines. However, the assay could be useful to detect the disease condition in birds vaccinated with recombinant vaccine expressing glycoproteins other than gD. The developed ILTV single serum dilution ELISA could be an alternative to the existing diagnostics for the detection of ILTV antibodies. 相似文献
110.
Yifei Jin Huan Cui Lina Jiang Cheng Zhang Jingjing Li Hongliang Cheng Zehui Chen Jing Zheng Yidun Zhang Yingying Fu Jiaming Li Li Li Zhendong Guo Bing Lu Zhongyi Wang 《Journal of medical virology》2023,95(1):e28242
H9N2 avian influenza virus (AIV) has become prevalent in the live poultry market (LPM) worldwide, and environmental transmission mode is an important way for AIVs to infect human beings in the LPM. To find evidence of human infection with the influenza A(H9N2) virus via environmental contamination, we evaluated one human isolate and three environmental isolates inside LPMs in Xiamen, China. The phylogeny, transmissibility, and pathogenicity of the four isolates were sorted out systematically. As for the H9N2 virus, which evolved alongside the “Avian-Environment-Human” spreading chain in LPMs from the summer of 2019 to the summer of 2020, its overall efficiency of contact and aerosol transmissibility improved, which might contribute to the increasing probability of human infection. This study indicated that environmental exposure might act as an important source of human infection in LPMs. 相似文献