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991.
OBJECTIVE--To investigate the association between fatal myocardial infarction and use of modern low-dose oral contraceptives. DESIGN--A case-control study. SETTING--General practices throughout England and Wales. SUBJECTS--161 women aged under 40 dying from myocardial infarction during 1986-1988. Living controls (2 per case), matched for age and marital status, were chosen from general practice lists. Information was collected during structured interviews with general practitioners, and from postal questionnaires sent to surviving partners of the cases and to control women. MAIN OUTCOME MEASURES--Mortality from myocardial infarction in relation to many risk factors, notably oral contraception, as measured by relative risk. RESULTS--After allowing for the confounding effects of medical risk factors and for surgical sterilization, the overall relative risk associated with both current and past use of oral contraceptives was estimated to be 1.9 (95% CI 0.7 to 4.9, and 1.0 to 3.5 respectively). The relative risk associated with current use of preparations containing 50 micrograms of oestrogen, however, was estimated to be 4.2 (0.5 to 39.2). At least some of the relative risk associated with oral contraceptive use is likely to be attributable to the confounding effect of cigarette smoking, but it is impossible to estimate how much from the available data. CONCLUSIONS--If there was an increased risk of fatal myocardial infarction associated with oral contraceptive use in 1986-1988 it is likely to have been less than two-fold; in this study risks were slightly, but not significantly, elevated with both current and previous use. It may be that any increase in risk is associated solely with the older combined preparations containing 50 micrograms of oestrogen.  相似文献   
992.
The diagnosis and management of ectopic pregnancy is changing rapidly. More sensitive pregnancy tests and high-resolution transvaginal sonography are making the diagnosis of ectopic pregnancy easier and earlier. In the future, we may become more confident with the ultrasound diagnosis of some ectopic pregnancies such that laparoscopic confirmation will not be required. These patients may be treated with systemic methotrexate. However, at the present time laparoscopy is essential for diagnostic confirmation of most ectopic pregnancies. It is senseless for a skilled laparoscopist to perform a diagnostic laparoscopy, remove the laparoscope, and then proceed with laparotomy or some nonsurgical treatment. There is sufficient evidence in the literature to demonstrate that laparoscopic management of ectopic pregnancies is equally safe, equally effective, and less traumatic than laparotomy. It should replace laparotomy as treatment for most ectopic pregnancies. Unfortunately, there are not enough trained laparoscopists to manage the 88,000 ectopic pregnancies per year in the United States. Operative laparoscopy deserves more emphasis in postgraduate and residency training programs.  相似文献   
993.
994.
The effectiveness of a low-dose oral contraceptive (OC) in suppressing plasma levels of gonadotropins, ovarian, and adrenal androgens and stimulating sex hormone-binding globulin (SHBG) was evaluated prospectively in nonhirsute women. Thirty-three women ingested 35 micrograms of ethinyl estradiol and 1 mg of norethindrone beginning within day 1 to 5 of the menstrual cycle. Baseline levels of luteinizing hormone, follicle-stimulating hormone, total testosterone (T), androstenedione (A), dehydroepiandrosterone sulfate (DHEAS), and SHBG were obtained before ingestion of the OC and repeated after 3, 6 and, 9 months of OC use on day 1 to 5 of the OC "cycle". A significant suppression of gonadotropin levels is seen in nonhirsute women. Sex hormone binding globulin is consistently stimulated by the low-dose OC. A significant suppression of T and DHEAS is observed. No change was seen in levels of A. The demonstrated effects become evident at 3 months and are maintained at 6 and 9 months.  相似文献   
995.
BACKGROUND: Previous studies of workers' compensation claims for low back pain (LBP) have revealed that the preponderance of disability is borne by a fraction of cases. However, less is known regarding the influence of occupational factors on these extreme conditions. METHODS: Workers' compensation claims (n=107,867) for LBP reported to a large, national insurer in 1992 were examined by antecedent event and industry class. In addition to summaries of the frequency and cost distribution, each factor was examined at two points on its cost distribution: one more representative of the typical case and one more representative of the case with long disability. These alternative disability indicators were introduced to explore a different perspective of LBP disability. RESULTS: The information provided by the alternative indicators was distinct from the information provided by the traditional aggregate indicators (claim frequency and claim cost frequency). In particular, this method identified increased severity for claims in the construction and services sectors, as well as for claims arising from falls and motor vehicle crashes. CONCLUSIONS: The results suggest that the construction and service sectors confront unique challenges to prevention and management of LBP disability. LBP related to discrete antecedents such as falls and motor vehicle crashes merits consideration on the basis of exceptionally severe disability.  相似文献   
996.
997.
998.
Pertussis in hospitalized children   总被引:2,自引:0,他引:2  
Before the whole-cell pertussis vaccine was available, Bordetella pertussis infections were an important cause of morbidity and mortality in infants. To determine the extent of continuing morbidity in an era of vaccination, a retrospective review was conducted of the records of neonates and infants hospitalized with pertussis infection at Parkland Memorial Hospital and Children's Medical Center, Dallas, Tex. During the 20 years from 1967 through 1986, 182 patients were younger than 24 months. Among 176 patients whose immunization history was recorded, 89% had received fewer than two doses of pertussis vaccine. The mean hospital stay was 7.4 days (range, 1 to 69 days). A convulsion occurred in 11 patients (6%). Apnea was reported in 45 patients (25%) and observed in the hospital in 26 (14%). Nine patients (5%) received mechanical ventilatory therapy. Intensive care monitoring was required in 18 patients (10%). Three (1.6%) died, all with secondary bacterial pneumonia. This hospital-based population indicates that pertussis continues to be a cause of serious morbidity and mortality in infants.  相似文献   
999.
Respiratory abnormalities are common presentations of malaria and acute respiratory tract infection, both of which are major causes of childhood mortality and morbidity in sub-Saharan Africa. Appropriate management depends on accurate assessment of disease severity which for the majority of children must be based on clinical signs alone. Choosing which signs best serve this purpose remains a considerable problem particularly in malaria endemic areas. As part of a prospective study to define clinical signs indicative of life threatening malaria video recordings were used to examine the level of agreement between clinicians for potentially important respiratory signs in 51 children. Overall agreement was good for recession, severe recession, and nasal flaring (kappa = 0.57, 0.50, and 0.60 respectively) and substantial for deep breathing and the summary impression of respiratory distress (kappa = 0.70 and 0.69 respectively). However, within this substantial variation in interpretation was apparent between individual observers from slight to almost perfect agreement (kappa values 0.10-0.92). Video is a useful tool to demonstrate interobserver variation and it may also allow training in recognition of signs and a means of standardising clinical signs between centres.  相似文献   
1000.
We present a case of interruption of the aortic arch (IAA) in association with aortic atresia. A pulmonary artery to ascending aorta fistulous channel at the level of the sinuses of Valsalva of the pulmonary artery was present and supplied the ascending aorta and coronary arteries. The communication had a significant length, so embryologically it is not an aortopulmonary window. There have been only three reported cases in the literature of IAA with aortic atresia; in none was a pulmonary artery to ascending aorta fistulous tract present.  相似文献   
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