全文获取类型
收费全文 | 7981篇 |
免费 | 530篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 89篇 |
儿科学 | 162篇 |
妇产科学 | 147篇 |
基础医学 | 1065篇 |
口腔科学 | 173篇 |
临床医学 | 956篇 |
内科学 | 1416篇 |
皮肤病学 | 146篇 |
神经病学 | 781篇 |
特种医学 | 328篇 |
外科学 | 1194篇 |
综合类 | 142篇 |
一般理论 | 17篇 |
预防医学 | 836篇 |
眼科学 | 84篇 |
药学 | 629篇 |
中国医学 | 5篇 |
肿瘤学 | 357篇 |
出版年
2023年 | 52篇 |
2022年 | 69篇 |
2021年 | 174篇 |
2020年 | 120篇 |
2019年 | 164篇 |
2018年 | 186篇 |
2017年 | 128篇 |
2016年 | 153篇 |
2015年 | 178篇 |
2014年 | 245篇 |
2013年 | 372篇 |
2012年 | 601篇 |
2011年 | 587篇 |
2010年 | 372篇 |
2009年 | 303篇 |
2008年 | 550篇 |
2007年 | 604篇 |
2006年 | 578篇 |
2005年 | 541篇 |
2004年 | 516篇 |
2003年 | 441篇 |
2002年 | 417篇 |
2001年 | 95篇 |
2000年 | 96篇 |
1999年 | 100篇 |
1998年 | 102篇 |
1997年 | 68篇 |
1996年 | 67篇 |
1995年 | 44篇 |
1994年 | 42篇 |
1993年 | 34篇 |
1992年 | 48篇 |
1991年 | 44篇 |
1990年 | 41篇 |
1989年 | 23篇 |
1988年 | 28篇 |
1987年 | 35篇 |
1986年 | 25篇 |
1985年 | 21篇 |
1984年 | 28篇 |
1983年 | 22篇 |
1982年 | 23篇 |
1981年 | 23篇 |
1980年 | 12篇 |
1978年 | 13篇 |
1977年 | 13篇 |
1975年 | 11篇 |
1973年 | 18篇 |
1967年 | 10篇 |
1966年 | 15篇 |
排序方式: 共有8527条查询结果,搜索用时 15 毫秒
991.
Rebecca B. Price Ben Paul Walt Schneider Greg J. Siegle 《Cognitive therapy and research》2013,37(4):657-672
Brain-based behavioral interventions targeting specific neurocognitive mechanisms show initial promise in the treatment of emotional disorders, but personalization of such approaches will be facilitated if brain targets are empirically established. As a preliminary step, we conducted a proof-of-concept study to test whether particular emotion regulatory neural circuitry can be differentially targeted by specific neurocognitive tasks, and whether these tasks effectively inhibit amygdala activity. Eleven healthy individuals underwent an idiographic sadness and guilt induction. Brain response was measured via fMRI during 4 subsequent emotion regulation conditions: fixation, cognitive reappraisal (selected to target the ventrolateral prefrontal cortex), working memory practice (selected to target the dorsolateral prefrontal cortex), and visual distraction (Tetris; selected to target occipital cortex). In whole-brain comparisons to fixation, hypotheses were upheld. Reappraisal uniquely activated left venrolateral prefrontal cortex, working memory practice uniquely activated left dorsolateral prefrontal cortex, and Tetris uniquely activated bilateral occipitoparietal cortex, activations that were largely robust at the single-subject level. All tasks inhibited amygdala activity relative to fixation. Data support examining whether repeated exposure to these tasks in psychiatric patients affects neural abnormalities implicated in emotional disorders. Ideally, psychiatric treatment will be accelerated by matching specific treatments to patients with specific neural profiles. 相似文献
992.
Caroline C. Henson Susan E. Davidson Yeng Ang Chris Babbs John Crampton Mark Kelly Simon Lal Jimmy K. Limdi Greg Whatley Ric Swindell Wendy Makin John McLaughlin 《Supportive care in cancer》2013,21(8):2255-2265
Purpose
Fifty percent of patients develop chronic gastrointestinal (GI) symptoms following pelvic radiotherapy that adversely affect quality of life. Fewer than 20 % are referred to a gastroenterologist. We aimed to determine if structured gastroenterological evaluation is of benefit to this patient group.Methods
Sixty patients with GI symptoms at ≥6 months after radical pelvic radiotherapy were identified prospectively from oncology clinics in this service evaluation. Those requiring urgent investigation were excluded. Patients were assessed at baseline using patient-reported questionnaires: inflammatory bowel disease questionnaire (IBDQ), Vaizey incontinence questionnaire, and the Common Terminology Criteria for Adverse Events (CTCAE) pelvis questionnaire. Participants were referred for gastroenterological evaluation using an algorithmic approach. Further assessments were made at 3 and 6 months.Results
Twenty men and 36 women with primary gynecological (31), urological (17), or lower GI (8) tumors were included (mean age, 58.5 years). Median time from radiotherapy to baseline assessment was 3.0 years. Multiple GI symptoms were reported (median, 8; range, 4–16) including frequency, urgency, loose stool, fecal incontinence, flatulence, bloating/distension, and rectal bleeding. Common diagnoses included radiation proctopathy, bile acid malabsorption, diverticulosis, and colonic polyps. Statistically significant improvements in all questionnaire scores between baseline and 6 months were found: IBDQ (p?=?0.014), Vaizey (p?<?0.0005), and CTCAE rectum-bowel subset (p?=?0.001).Conclusions
Gastroenterological evaluation identifies significant, potentially treatable diagnoses in patients who develop chronic GI symptoms following pelvic radiotherapy. Some findings are incidental and unrelated to previous cancer treatment. Radiation-induced GI symptoms have historically been considered “untreatable.” We report the first data to show that structured gastroenterological assessment has the potential to improve outcome by identifying diagnoses and facilitating focused treatment. 相似文献993.
Catherine Windrim Greg Athaide Tracy Gerster John C.P. Kingdom 《Journal d'obstetrique et gynecologie du Canada》2011,33(5):475-479
BackgroundSmall hematomas on the placental surface, termed subamniotic hemorrhage, are a common finding either at the routine 18- to 20-week anatomy ultrasound or at subsequent assessments of fetal growth and well-being. Hemorrhage beneath or at the edge of the placenta, or behind an isolated area of the fetal membranes, is of greater concern.The CasesWe describe the ultrasound findings and clinical outcomes in two women with a diagnosis of massive intrauterine hematoma arising from the fetal membranes. Both required blood transfusion because of the extent of concealed and revealed bleeding. In each case the initial placental appearances and uterine artery Doppler studies were normal. Both hematomas resolved with growth of the fetus and amniotic sac. Each neonate survived the perinatal period favourably. One was born vaginally at 32 weeks’ gestation following premature preterm rupture of the membranes, and the second was born by emergency Caesarean section at 37 weeks because of a recurrence of antepartum hemorrhage.ConclusionsLarge intrauterine hematomas may be acutely detrimental to maternal health in the second trimester. Ultrasound assessment of the placenta is useful to define the perinatal prognosis and may demonstrate gradual resolution. Despite a dramatic initial presentation, this finding may be compatible with a favourable outcome. 相似文献
994.
Peter McCroskery Carol A Wallace Daniel J Lovell Scott Stryker Nataliya Chernyukhin Consuelo Blosch Debra J Zack 《Pediatric rheumatology online journal》2010,8(1):18
Background
Concerns have been raised about a potential link between the use of TNF inhibitors and development of malignancy in the pediatric population. We examined the worldwide experience of etanercept use in pediatric patients and the occurrence of malignancies as reported from clinical trials, registry studies, post-marketing surveillance, and published scientific literature. 相似文献995.
996.
Wellington Yugo Yamaoka Luís Carlos Gregório 《Revista brasileira de otorrinolaringologia (English ed.)》2012,78(5):44-50
Synechia is the most frequent complication after sinus surgery and has been reported in up to 36% of cases. Several types of materials have been used to reduce the incidence of synechia, including Mitomycin C (MMC).ObjectiveThis prospective study aimed to assess the effectiveness of topical MMC in the prevention of synechia after sinus surgery in humans.MethodsAt the end of surgery, MMC solution (1.0 mg/ml) was topically applied randomly to one of the middle meatuses (MMC group) of 14 patients while saline solution was applied to the contralateral meatus (control group). The author remained blind to the medicated side. Synechiae were classified as partial or total.ResultsThree patients had middle meatus synechia in the MMC group (21.43%) versus nine (64.29%) in the control group (p = 0.054). In the MMC group, all three middle meatus synechia were partial, while in the control group there were four partial (28.57%) and five total (35.71%) cases of synechia (p = 0.025).ConclusionsMitomycin C was not effective in preventing middle meatus synechia, but reduced the probability of total synechia formation. 相似文献
997.
998.
Objective: To assess whether site of prenatal care influences the content of prenatal care for low-income women. Design: Bivariate and logistic analyses of prenatal care content for low-income women provided at five different types of care sites (private offices, HMOs, publicly funded clinics, hospital clinics, and other sites of care), controlling for sociodemographic, behavioral, and maternal health characteristics. Participants: A sample of 3405 low-income women selected from a nationally representative sample of 9953 women surveyed by the National Maternal and Infant Health Survey, who had singleton live births in 1988, had some prenatal care (PNC), Medicaid participation, or a family income less than $12,000/year. Outcome Measures: Maternal report of seven initial PNC procedures (individually and combined), six areas of PNC advice (individually and combined), and participation in the Women Infant Children (WIC) nutrition program. Results: The content of PNC provided for low-income women does not meet the recommendations of the U.S. Public Health Service, and varies by site of delivery. Low-income women in publicly funded clinics (health departments and community health centers) report receiving more total initial PNC procedures and total PNC advice and have greater participation in the WIC program than similar women receiving PNC in private offices. Conclusions: Publicly funded sites of care appear to provide more comprehensive prenatal care services than private office settings. Health care systems reforms which assume equality of care across all sites, or which limit services to restricted sites, may foster unequal access to comprehensive PNC. 相似文献
999.
John Dickinson Jiu Hu Neil Chester Mike Loosemore Greg Whyte 《Journal of Sports Science and Medicine》2014,13(2):271-279
Whilst there appears to be no ergogenic effect from inhaled salbutamol no study has investigated the impact of the acute inhalation of 1600 µg, the World Anti-Doping Agency (WADA) daily upper limit, on endurance running performance. To investigate the ergogenic effect of an acute inhalation of short acting β2-agonists at doses up to 1600 µg on 5 km time trial performance and resultant urine concentration. Seven male non-asthmatic runners (mean ± SD; age 22.4 ± 4.3 years; height 1.80 ± 0.07 m; body mass 76.6 ± 8.6 kg) provided written informed consent. Participants completed six 5 km time-trials on separate days (three at 18 °C and three at 30 °C). Fifteen minutes prior to the initiation of each 5 km time-trial participants inhaled: placebo (PLA), 800 µg salbutamol (SAL800) or 1600 µg salbutamol (SAL1600). During each 5 km time-trial HR, VO2, VCO2, VE, RPE and blood lactate were measured. Urine samples (90 ml) were collected between 30-180 minutes post 5 km time-trial and analysed for salbutamol concentration. There was no significant difference in total 5 km time between treatments (PLA 1714.7 ± 186.2 s; SAL800 1683.3 ± 179.7 s; SAL1600 1683.6 ± 190.7 s). Post 5 km time-trial salbutamol urine concentration between SAL800 (122.96 ± 69.22 ug·ml-1) and SAL1600 (574.06 ± 448.17 ug·ml-1) were not significantly different. There was no improvement in 5 km time-trial performance following the inhalation of up to 1600 µg of salbutamol in non-asthmatic athletes. This would suggest that the current WADA guidelines, which allow athletes to inhale up to 1600 µg per day, is sufficient to avoid pharmaceutical induced performance enhancement.
Key points
- Inhaling up to 1600 µg of Salbutamol does not result in improved 5 km time trial performance.
- The position of Salbutamol on the World Anti-Doping Agency list of prohibited appears justified.
- Athletes who use up to 1600 µg Salbutamol in one day need to review their therapy as it would suggest their respiratory condition is not under control.
1000.