全文获取类型
收费全文 | 25763篇 |
免费 | 1795篇 |
国内免费 | 169篇 |
专业分类
耳鼻咽喉 | 208篇 |
儿科学 | 575篇 |
妇产科学 | 470篇 |
基础医学 | 3664篇 |
口腔科学 | 259篇 |
临床医学 | 2310篇 |
内科学 | 6041篇 |
皮肤病学 | 331篇 |
神经病学 | 2609篇 |
特种医学 | 869篇 |
外国民族医学 | 1篇 |
外科学 | 4777篇 |
综合类 | 160篇 |
一般理论 | 9篇 |
预防医学 | 1575篇 |
眼科学 | 289篇 |
药学 | 1544篇 |
中国医学 | 77篇 |
肿瘤学 | 1959篇 |
出版年
2023年 | 120篇 |
2022年 | 243篇 |
2021年 | 489篇 |
2020年 | 361篇 |
2019年 | 595篇 |
2018年 | 649篇 |
2017年 | 492篇 |
2016年 | 542篇 |
2015年 | 631篇 |
2014年 | 888篇 |
2013年 | 1213篇 |
2012年 | 1818篇 |
2011年 | 1964篇 |
2010年 | 1194篇 |
2009年 | 1127篇 |
2008年 | 1725篇 |
2007年 | 1774篇 |
2006年 | 1652篇 |
2005年 | 1728篇 |
2004年 | 1526篇 |
2003年 | 1551篇 |
2002年 | 1577篇 |
2001年 | 230篇 |
2000年 | 192篇 |
1999年 | 255篇 |
1998年 | 335篇 |
1997年 | 320篇 |
1996年 | 225篇 |
1995年 | 217篇 |
1994年 | 173篇 |
1993年 | 171篇 |
1992年 | 137篇 |
1991年 | 124篇 |
1990年 | 116篇 |
1989年 | 91篇 |
1988年 | 91篇 |
1987年 | 69篇 |
1986年 | 101篇 |
1985年 | 86篇 |
1984年 | 91篇 |
1983年 | 92篇 |
1982年 | 101篇 |
1981年 | 90篇 |
1980年 | 88篇 |
1979年 | 56篇 |
1978年 | 45篇 |
1977年 | 37篇 |
1976年 | 37篇 |
1975年 | 36篇 |
1974年 | 35篇 |
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
51.
Alain Deschamps Steven B Backman Vera Novak Gilles Plourde Pierre Fiset Daniel Chartrand 《The Journal of pharmacology and experimental therapeutics》2002,300(1):112-117
Edrophonium, an anticholinesterase, exerts a biphasic effect on cardiovascular autonomic drive in humans (lower doses enhance; higher doses reduce). Twenty-five anesthetized, mechanically respired (10 breaths. min(-1), constant tidal volume) patients were given either saline (n = 10) or edrophonium (0.01-1.0 mg. kg(-1), n = 15) following surgery. ECG, radial arterial pressure, and respiratory rate were sampled at 250 Hz to obtain time series for consecutive R-R intervals (RRIs), and systolic (SBP) and diastolic blood pressure (DBP). A Wigner distribution was used for time frequency mapping of spectral powers at high (HFP, 0.15-0.5 Hz) and low (LFP, 0.0-0.05 Hz) frequency. Edrophonium produced a dose-dependent decrease in heart rate [baseline 66.8 +/- 1.9 (S.E.M.) beats per minute; maximum decrease to 55.8 +/- 1.4 beats per minute with 1.0 mg. kg(-1), P < 0.01]. HFP of the RRI increased at low doses (0.2-0.4 mg. kg(-1); maximum increase to 111.0 +/- 58.2% baseline; P < 0.01) but decreased (-49.5 +/- 35.5% baseline; P < 0.01) at higher (1.0 mg. kg(-1)) doses. Edrophonium had no effect on SBP and DBP. HFP of SBP decreased with increasing doses (maximal decrease to -26.2 +/- 7.5% baseline, P < 0.01, 1.0 mg. kg(-1)). LFP of SBP was also decreased (-46.3 +/- 10.9% baseline, P < 0.01, 1.0 mg. kg(-1)). Edrophonium may enhance (lower dose) or reduce (higher dose) cardiovascular autonomic drive in humans, as evidenced by the significant changes it evokes in HFP of the RRI (parasympathetic drive), and in the HFP and LFP of SBP (sympathetic drive). These observations may account for the modest autonomic side effects of edrophonium when this drug is used clinically. 相似文献
52.
53.
54.
Marie-Francoise Dresse Michele David Heather Hume Herve Blanchard Pierre Russo Nicolas Van Doesberg Georges E. Rivard 《Pediatric hematology and oncology》1991,8(4):329-334
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA. 相似文献
55.
Pierre Pradat 《Genetic epidemiology》1994,11(2):131-140
During the period 1981–1986, 1605 infants presenting a major congenital heart defect (CHD) were identified in Sweden. Using the personal identification numbers of the mothers, 1507 of them could be linked to the Medical Birth Registry and two controls were selected for each infant. For this total of 4521 infants, 2686 postoccurrence sibs born during the period 1981–1989 were identified from the Medical Birth Registry. The tendency to have one or more sibs was higher among cases than among controls and was correlated to the life status of the proband. This tendency did not vary according to the type of CHD when controlling for life status. The prevalence at birth of CHD was almost four times higher among sibs of CHD infants than among sibs of normal infants. The tendency to have a sib with an extracardiac malformation did not differ between CHD probands and normal probands. The importance of only including births occurring after the proband when evaluating recurrence risks is stressed. © 1994 Wiley-Liss, Inc. 相似文献
56.
Pierre Beaulieu 《Journal canadien d'anesthésie》2006,53(8):769-775
PURPOSE: Cannabinoids have been shown to have analgesic properties in animal studies, but a potential role for these drugs in acute pain management has not been established. It was hypothesized that nabilone, an oral cannabinoid synthetic tetrahydrocannabinol analogue, decreases morphine consumption, pain scores, nausea and vomiting following major surgery. METHODS: A double-blind, randomized, placebo-controlled, parallel-group pilot trial compared the effects of two different doses, 1 mg (n = 11) and 2 mg (n = 9) of nabilone, ketoprofen 50 mg (n = 11) or placebo (n = 10), given at eight-hour intervals for 24 hr. Outcomes included morphine consumption, pain scores and emesis after major surgery. Secondary outcomes included patient tolerability of the study medication. RESULTS: Forty-one patients (mean age 52 +/- 2 yr) undergoing gynecologic (46%), orthopedic (44%), or other (10%) surgery were recruited. Cumulative 24-hr morphine consumption was not different between the four groups, but pain scores at rest and on movement were significantly higher in the 2 mg nabilone group compared to the other groups. There were no significant differences between groups with respect to episodes of nausea and vomiting, quality of sleep, sedation, euphoria, pruritus, or the number and severity of adverse events. No serious adverse event was recorded. CONCLUSIONS: Contrary to the main hypothesis, high dose nabilone in the presence of morphine patient controlled analgesia is associated with an increase in pain scores in patients undergoing major surgery. 相似文献
57.
Renaud de Beaurepaire Michael Lukasiewicz Patrick Beauverie Sophie Castra Odile Dagorne Renaud Espaze Bruno Falissard Patrick Giroult Michle Houery Georges Mahuzier Isabelle Matheron Philippe Niel Pierre Padovani Nicole Poisson Jean-Paul Richier Jrme Rocher Odile Ruetsh Didier Touzeau Andr Visinoni Robert Molimard 《European psychiatry》2007,22(8):540-548
BACKGROUND: Asking psychiatric in-patients about their drug consumption is unlikely to yield reliable results, particularly where alcohol and illicit drug use is involved. The main aim of this study was to compare spontaneous self-reports of drug use in hospitalized psychiatric patients to biological measures of same. A secondary aim was to determine which personal factors were associated with the use of tobacco, alcohol, and illicit drugs as indicated by these biological measures. METHODS: The consumption of substances was investigated using biological measures (urine cotinine, cannabis, opiates, cocaine, amphetamines and barbiturates; blood carbohydrate-deficient transferrin [CDT] and gamma-glutamyl transferase [GGT]) in 486 consecutively admitted psychiatric patients, one day following their hospitalization. Patients' self-reports of alcohol, tobacco and illicit drugs consumption were recorded. Socio-professional and familial data were also recorded. RESULTS: The results show a low correlation between biological measures and self-reported consumption of alcohol and illicit drugs. Fifty-two percent of the patients under-reported their consumption of illicit drugs (kappa=.47). Patients with schizophrenia and personality disorders were more likely to disclose their illicit drug consumption relative to patients suffering from mood disorders and alcohol dependence. Fifty-six percent of patients underreported alcohol use, as evaluated by CDT (kappa=.2), and 37% underreported when using the CDT+GGT measure as an indicator. Smoking appeared to be reported adequately. In the study we observed a strong negative correlation between cannabis use and age, a strong correlation between tobacco and cannabis use, and correlations between tobacco, cannabis and alcohol consumption. CONCLUSION: This study is the first to compare self-reports and biological measures of alcohol, tobacco and illicit drug uses in a large sample of inpatients suffering from various categories of psychiatric illnesses, allowing for cross-diagnosis comparisons. 相似文献
58.
Ute Bültmann Renée-Louise Franche Sheilah Hogg-Johnson Pierre Côté Hyunmi Lee Colette Severin Marjan Vidmar Nancy Carnide 《Quality of life research》2007,16(7):1167-1178
BACKGROUND: The purpose of this study was to describe the health status and work limitations in injured workers with musculoskeletal disorders at 1 month post-injury, stratified by return-to-work status, and to document their return-to-work trajectories 6 months post-injury. METHODS: A sample of 632 workers with a back or upper extremity musculoskeletal disorder, who filed a Workplace Safety and Insurance Board lost-time claim injury, participated in this prospective study. Participants were assessed at baseline (1 month post-injury) and at 6 months follow-up. RESULTS: One month post-injury, poor physical health, high levels of depressive symptoms and high work limitations are prevalent in workers, including in those with a sustained first return to work. Workers with a sustained first return to work report a better health status and fewer work limitations than those who experienced a recurrence of work absence or who never returned to work. Six months post-injury, the rate of recurrence of work absence in the trajectories of injured workers who have made at least one return to work attempt is high (38%), including the rate for workers with an initial sustained first return to work (27%). CONCLUSIONS: There are return-to-work status specific health outcomes in injured workers. A sustained first return to work is not equivalent to a complete recovery from musculoskeletal disorders. 相似文献
59.
60.