全文获取类型
收费全文 | 1311篇 |
免费 | 64篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 19篇 |
妇产科学 | 46篇 |
基础医学 | 181篇 |
口腔科学 | 13篇 |
临床医学 | 161篇 |
内科学 | 222篇 |
皮肤病学 | 6篇 |
神经病学 | 148篇 |
特种医学 | 66篇 |
外科学 | 165篇 |
综合类 | 35篇 |
预防医学 | 125篇 |
眼科学 | 12篇 |
药学 | 85篇 |
中国医学 | 1篇 |
肿瘤学 | 90篇 |
出版年
2023年 | 14篇 |
2022年 | 11篇 |
2021年 | 15篇 |
2020年 | 19篇 |
2019年 | 26篇 |
2018年 | 25篇 |
2017年 | 13篇 |
2016年 | 21篇 |
2015年 | 22篇 |
2014年 | 36篇 |
2013年 | 54篇 |
2012年 | 77篇 |
2011年 | 81篇 |
2010年 | 51篇 |
2009年 | 34篇 |
2008年 | 64篇 |
2007年 | 80篇 |
2006年 | 70篇 |
2005年 | 61篇 |
2004年 | 61篇 |
2003年 | 50篇 |
2002年 | 41篇 |
2001年 | 43篇 |
2000年 | 42篇 |
1999年 | 47篇 |
1998年 | 12篇 |
1997年 | 15篇 |
1996年 | 10篇 |
1995年 | 9篇 |
1994年 | 9篇 |
1992年 | 14篇 |
1991年 | 19篇 |
1990年 | 26篇 |
1989年 | 18篇 |
1988年 | 17篇 |
1987年 | 16篇 |
1986年 | 15篇 |
1985年 | 10篇 |
1984年 | 9篇 |
1983年 | 17篇 |
1979年 | 7篇 |
1978年 | 6篇 |
1977年 | 9篇 |
1975年 | 8篇 |
1973年 | 6篇 |
1972年 | 8篇 |
1970年 | 6篇 |
1968年 | 8篇 |
1967年 | 5篇 |
1966年 | 6篇 |
排序方式: 共有1381条查询结果,搜索用时 0 毫秒
71.
Major non-cardiac surgery within 40 days of coronary angioplasty with stenting has high cardiac complication rates. We have performed a case-control study to determine whether the risk of vascular surgery might have increased in recent survivors of coronary artery bypass surgery (CABG). Using our vascular database from 1990 to 1999, we matched the cases who had vascular surgery within a month of CABG with controls by pre-operative comorbidities of diabetes mellitus, history of myocardial infarction (MI), history of congestive heart failure (CHF), and chronic renal insufficiency and compared the incidence of peri-operative MI, CHF, death, and other complications. Compared to case-matched controls, patients who underwent vascular surgery within a month of CABG suffered significantly greater mortality (20.6% vs. 3.9%, p < 0.005). The incidence of non-fatal cardiac complications was not significantly different between the groups. We conclude that the risk of mortality may be significantly greater in patients undergoing major vascular surgery within a month of CABG. 相似文献
72.
Paradoxical reactions during tuberculosis treatment in patients with and without HIV co-infection 总被引:8,自引:0,他引:8
下载免费PDF全文
![点击此处可从《Thorax》网站下载免费的PDF全文](/ch/ext_images/free.gif)
BACKGROUND: It has been suggested that deterioration of tuberculosis (TB) during appropriate treatment, termed a paradoxical reaction (PR), is more common and severe in HIV positive individuals on highly active antiretroviral therapy (HAART). METHOD: A study was undertaken to determine the frequency of PR and its associated features in a population of HIV+TB+ patients and a similar sized group of HIV-TB+ individuals. RESULTS: PR occurred in 28% of 50 HIV+TB+ patients and 10% of 50 HIV-TB+ patients. Disseminated TB was present in eight of 13 HIV+TB+ patients and four of five HIV-TB+ patients with PR. In 28 HIV+TB+ patients starting HAART, PR was significantly associated with commencing HAART within 6 weeks of starting antituberculosis treatment (p = 0.03) and was more common in those with disseminated TB (p = 0.09). No association was found between development of PR and baseline CD4 count or CD4 response to HAART. CONCLUSIONS: PR is common in HIV infected and uninfected individuals with TB. Early introduction of HAART and the presence of disseminated TB appear to be important in co-infected patients. 相似文献
73.
Breen KJ 《The Medical journal of Australia》2004,180(8):409-410
There is evidence that drug-marketing techniques affect doctors' prescribing practices. This has ethical implications for doctors, as it affects the trust required in the doctor-patient relationship. Doctors need to recognise they are affected by drug marketing, and take steps to maintain their independence from the pharmaceutical industry. 相似文献
74.
BACKGROUND: Cervical cancer screening is not fully utilized among all groups of women in the United States, especially women without access to health care and older women. METHODS: Papanicolaou (Pap) test use among U.S. women age 18 and older is examined using data from the 2000 National Health Interview Survey (NHIS). RESULTS: Among women who had not had a hysterectomy (n = 13,745), 83% reported having had a Pap test within the past 3 years. Logistic regression analyses showed that women with no contact with a primary care provider in the past year were very unlikely to have reported a recent Pap test. Other characteristics associated with lower rates of Pap test use included lacking a usual source of care, low family income, low educational attainment, and being unmarried. Having no health insurance coverage was associated with lower Pap test use among women under 65. Despite higher insurance coverage, being age 65 and older was associated with low use. Rates of recent Pap test were higher among African-American women. CONCLUSIONS: Policies to generalize insurance coverage and a usual source of health care would likely increase use of Pap testing. Also needed are health system changes such as automated reminders to assist health care providers implement appropriate screening. Renewed efforts by physicians and targeted public health messages are needed to improve screening among older women without a prior Pap test. 相似文献
75.
Prostate-specific antigen test use reported in the 2000 National Health Interview Survey 总被引:7,自引:0,他引:7
BACKGROUND: In 2000, the National Health Interview Survey (NHIS) collected information about prostate-specific antigen (PSA) test use in a representative sample of U.S. men. METHODS: This study examined PSA test use in subgroups defined by personal and social characteristics. RESULTS: Among men aged 50 and older with no history of prostate cancer, 56.8% reported ever having had a PSA test, 34.1% reported having had a screening PSA test during the previous year, and 30.0% reported having had three or more tests during the previous 5 years. Screening was greater among men aged 60-79 years, those with greater access to care, and those practicing other preventive behaviors. Among men in their 40s, use tended to be higher among African-American men. CONCLUSIONS: The prevalence and patterns of PSA screening suggest that PSA is used like other cancer screening tests among about a third of U.S. men. Because of the lack of scientific consensus on whether prostate cancer screening is beneficial, more information is needed on how knowledgeable both patients and practitioners are about the potential benefits and harms of screening and how prostate cancer screening decisions are made. 相似文献
76.
Etzioni DA Ponce NA Babey SH Spencer BA Brown ER Ko CY Chawla N Breen N Klabunde CN 《Cancer》2004,101(11):2523-2532
BACKGROUND: Recent research has supported the use of colorectal cancer (CRC) tests to reduce disease incidence, morbidity, and mortality. A new health survey has provided an opportunity to examine the use of these tests in California's ethnically diverse population. The authors used the 2001 California Health Interview Survey (CHIS 2001) to evaluate 1) rates of CRC test use, 2) predictors of the receipt of tests, and 3) reasons for nonuse of CRC tests. METHODS: The CHIS 2001 is a random-digit dial telephone survey that was conducted in California. Responses were analyzed from 22,343 adults age >/= 50 years. CRC test use was defined as receipt of a fecal occult blood test in the past year and/or receipt of an endoscopic examination in the past 5 years. RESULTS: Nearly 54% of California adults reported receipt of a recent CRC test. Insurance coverage and having a usual source of care were the most important predictors of CRC testing. Latinos age < 65 years were less likely to be tested than whites (relative risk [RR], 0.84; 95% confidence interval [95% CI], 0.77-0.92). Men were more likely to be tested than women, an effect that was greater among individuals age 50-64 years (RR, 1.28; 95% CI, 1.23-1.32) than among individuals age >/= 65 years (RR, 1.19; 95% CI, 1.15-1.23). Women were more likely than men to say that their physician did not inform them the test was needed and that CRC tests were painful or embarrassing. CONCLUSIONS: Results of the current study indicate a need for physicians to recommend CRC testing to their patients. Assuring that all individuals have both health insurance and a usual source of care would help address gaps in the receipt of CRC tests. 相似文献
77.
Single O-linked N-acetylglucosamine (O-GlcNAc) sugar residues can compete with phosphate groups to occupy specific sites on certain nuclear and cytosolic proteins. Here we show that inhibiting cellular kinase activities resulted in changes in protein O-glycosylation levels in heat-stable cytoskeletal protein fractions derived from primary neuronal cells. As increased phosphorylation of the microtubule-associated protein tau is one of the pathological hallmarks of Alzheimer's disease and glycosylation may play an influential role in this process. We observed a significant decrease in the protein O-GlcNAc glycosylation of a tau-enriched cytoskeletal fraction generated from AD post-mortem brain samples as compared with control, suggesting an inverse relationship between the two post-translational modifications. Finally, cells transfected with the cDNA coding for O-GlcNAc transferase (OGT) displayed altered tau phosphorylation patterns as compared with control cells, suggesting that changes in tau glycosylation may influence its phosphorylation state. The specificity of the changes in the phosphorylation of individual amino acid residues provides evidence for a targeted O-glycosylation of tau. 相似文献
78.
Since 1996, the Illicit Drug Reporting System (IDRS), Australia's strategic early warning system for illicit drug trends, has monitored annual trends in the markets for the four main illicit drug classes, cannabis, methamphetamine, cocaine and heroin. In 2000, a 2-year trial was implemented to examine the feasibility of using similar methodology to monitor trends in the markets for 'party drugs'. A triangulation of three data sources was sought: (1) quantitative interviews with a 'sentinel' population of drug users; (2) qualitative interviews with key informants (KIs), or those who have contact with drug users through their work; (3) extant indicator data sources such as the purity of illicit drugs seized by law enforcement agencies. The results suggested that the feasibility of collecting detailed, reliable and valid data about party drug markets is a direct function of the size of those markets. The trial demonstrated that the system would allow the successful monitoring of markets for party drugs that are relatively widely used, such as ecstasy, but would be less sensitive in monitoring markets for party drugs that are used by small proportions of the total population, such as gamma-hydroxy-butyrate (GHB) and ketamine. Methodological issues encountered during the conduct of this trial are discussed, including defining the appropriate sentinel population of drug users, identifying relevant key informants, and the relative absence of extant indicator data sources that could inform our understanding of party drug markets. 相似文献
79.
The aim of this study was to examine changes in drug use patterns among groups of injecting drug users (IDU) who remained in the drug market during a period of reduced heroin availability in NSW, Australia. Cross-sectional data collected from regular IDU interviewed as part of the NSW Illicit Drug Reporting System (IDRS) between 1996 - 2003 were analysed. Drug use patterns, reported drug availability and price were assessed. There was a marked decrease in the frequency of heroin use during the period of reduced availability in 2001, with some increase in 2002 and 2003. Heroin availability and frequency of use have not returned to levels reported prior to 2001; however; even at the peak of the reduction in supply, users continued to access heroin. There was a significant shift among IDU from heroin to cocaine during 2001, which subsequently reversed. The availability of cocaine has fluctuated in recent years, but the price has remained stable. The price of heroin appeared to be more responsive to market fluctuations, and co-varied with heroin availability. IDU used cocaine when heroin was less available; however, patterns of cocaine use were not maintained. The frequency of heroin use remained lower, which may be indicative of a less consistent supply, increased price or increased numbers of IDU entering treatment. The reduced supply of heroin in 2001 highlighted the adaptable nature of IDU patterns of use, indicative of the need for a commensurate treatment response. It also highlighted the importance of the ongoing monitoring of drug trends in Australia. [Roxburgh A, Degenhardt L, Breen C. Changes in patterns of drug use among injecting drug users following changes in the availability of heroin in New South Wales, Australia. Drug Alcohol Rev 2004;23:287-294] 相似文献
80.
Breen J 《ANS. Advances in nursing science》2002,24(4):48-59
Chronic pain is a worldwide problem with significant physical, psychological, and social impacts. Despite its prevalence and cost, the phenomenon is not well understood. An inductive method of concept analysis was used to study the concept of chronic, non-cancerous pain in adults. A random sample of nursing, psychology, and neurophysiology literature published over a 30-year period (1969 through 1999) was used to generate a consensual definition of chronic pain. The transition in the attributes, antecedents, consequences, related concepts, and surrogate terms of chronic pain is described, and the implications of the findings for practice and research are discussed. 相似文献