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排序方式: 共有2068条查询结果,搜索用时 937 毫秒
21.
Christians F Connolly D Tsuchiya K True L Loeb L 《International journal of oncology》1995,6(6):1173-1176
DNA replication errors are especially frequent in repetitive DNA sequences, including microsatellites. Thus, microsatellites are sensitive indicators of the genetic instability observed in many types of human cancers, particularly colorectal cancer. We tested prostate carcinomas for the presence of microsatellite alleles not present in normal tissue from the same individuals. Analysis of 7 microsatellites in each of 30 patients revealed instability at only one microsatellite in one tumor. This level of microsatellite instability, considerably lower than that reported previously, may reflect differences in patient pools. We discuss the implications of the genetic stability of prostate cancers relative to other cancers. 相似文献
22.
J M Moran D W Burke J M Loeb A J Roberts J H Sanders L L Michaelis 《The Annals of thoracic surgery》1981,32(5):506-509
A blood flow calibration apparatus is described for use with electromagnetic flow probes. It is an automatic gravity-flow system, which provides a constant level and therefore constant flow at any preset rate. On several occasions, the use of this device has helped to determine whether flow probes require simple adjustment, factory repair, or replacement. Using this system, a systematic error in the manufacturer's "precalibration" averaging +22% (range, 9 to 50%) has been discovered, and appropriate corrections have been made. The accuracy of these corrections has been confirmed by a rapid, in vivo method of calibration, which also is described and which can be carried out during the conduct of aortocoronary bypass operation. It is recommended that all groups measuring coronary graft flow become familiar with their electromagnetic flowmeter and probes by means such as those described, in the interest of accurate flow measurement after bypass operation. 相似文献
23.
Liebman J Kotranski L Loeb JG Eckels T Arnold J Needleman J 《Journal of health & social policy》1991,3(2):71-89
Pennsylvania is currently considering legislative options to expand coverage and improve access to medical care for state residents who lack health insurance. Relevant data are presented from a telephone survey of 10,809 Pennsylvania households. Almost nine percent (8.5%) of the state's population lacks health insurance, representing over one million people. Those most likely to be uninsured are children and young adults, non-whites and the poor. A substantial number of poor people are not covered by the state's Medicaid program. The uninsured report poorer health status, more obstacled to receiving care and greater use of hospital services for primary care. 相似文献
24.
The contemporary practice of medicine depends on the use of a wide array of technologies that did not exist 40 years ago. An exponential increase in our scientific knowledge base, and the subsequent application of this new information to clinical practice, have dramatically extended longevity, enhanced the quality of life, and improved the overall health status of the American public. Clinical medicine has become "a set of technologies for diagnosis, prevention, treatment, and rehabilitation." 相似文献
25.
We report our clinical experience with phototherapy in 3802 infants; 3629 were exposed to "standard" daylight phototherapy and 173 to "high-intensity" blue-light phototherapy. High-intensity blue-light phototherapy was twice as effective as standard daylight phototherapy in decreasing bilirubin concentrations. No failures occurred with high-intensity phototherapy compared with an overall failure rate of 1.84/1000 with daylight lamps; these cases were transferred to high-intensity phototherapy with prompt response. Rebound after cessation of phototherapy was greater in those exposed to high-intensity blue light with a significantly greater number requiring a second exposure. However, the incidence was still low. No third exposure was required in any infant. Nursing of infants under high-intensity blue light was more difficult and inconvenient as was clinical monitoring. The light also caused more stress on the nursing and medical personnel. However, the infants tolerated both types of phototherapy equally well. High-intensity blue-light phototherapy would seem to be the treatment of choice for infants with rapidly increasing or very high bilirubin levels, as well as in those not responding adequately to daylight phototherapy. 相似文献
26.
Fatalities among British Columbia fallers and buckers 1981-7 总被引:1,自引:0,他引:1
D A Salisbury R Brubaker C Hertzman G R Loeb 《Canadian journal of public health. Revue canadienne de santé publique》1991,82(1):32-37
In Canada, the forest industry has the highest rate of lost time injury (161 per thousand workers in 1986) and has the highest fatality rate (1.04 per thousand workers in 1986) of all industries. A retrospective case series of fatal accidents occurring among those employed as fallers or buckers in the British Columbia Forest Industry was studied. 87 cases were found and the files of the provincial coroner were accessed to provide data on these accidents. Due to a lack of denominator data, no risk factors could be identified by several hypotheses for future research were developed. These included: the possibility that lack of work experience and young age may play a role in these accidents, the observation that there are "peaks of incidence" just before noon, on Mondays and Thursdays and in January. There was also the surprising finding of the lack of toxicological evidence indicating impairment of any of these workers. Future directions for research are discussed. 相似文献
27.
Abstract: We report the first case of fatal anthrax meningoencephalitis in Hong Kong over the past 60 years. A 13 year-old boy presented with right lower quadrant pain, diarrhoea and progressive headache. Lumbar puncture yielded gram positive bacilli initially thought to be Bacillus cereus, a contaminant. He was treated with ampicillin and cefotaxime, but died 3 days after hospitalization. The organism isolated from blood and cerebrospinal fluid was later identified as Bacillus anthracis. 相似文献
28.
To report our clinical experience on the use of oral erythromycin for the treatment of severe gastrointestinal dysmotility in preterm infants.
A case series study of seven preterm infants (six were very low birthweight) with severe intestinal dysmotility in a tertiary neonatal centre.
All responded favourably without adverse effects and tolerated full enteral feeding within 1–2 weeks of the commencement of the drug.
As prolonged total parenteral nutrition carries significant risk of complications, this therapy could be considered in selected preterm infants who fail to establish enteral feeding after an extended period, and in whom an anatomically obstructive lesion of the gastrointestinal tract has been excluded. Meanwhile, we would caution against the widespread implementation of this therapeutic approach until formal evaluation by randomized controlled trials have established the exact role of erythromycin, or its analogues, in the treatment of intestinal dysmotility in preterm infants. 相似文献
Methodology:
A case series study of seven preterm infants (six were very low birthweight) with severe intestinal dysmotility in a tertiary neonatal centre.
Results:
All responded favourably without adverse effects and tolerated full enteral feeding within 1–2 weeks of the commencement of the drug.
Conclusions:
As prolonged total parenteral nutrition carries significant risk of complications, this therapy could be considered in selected preterm infants who fail to establish enteral feeding after an extended period, and in whom an anatomically obstructive lesion of the gastrointestinal tract has been excluded. Meanwhile, we would caution against the widespread implementation of this therapeutic approach until formal evaluation by randomized controlled trials have established the exact role of erythromycin, or its analogues, in the treatment of intestinal dysmotility in preterm infants. 相似文献
29.
30.
OBJECTIVE: Because the survival rate has increased for extremely low birth weight neonates, many have raised the concern that the rate of developmental disability among survivors will also increase. To address this concern, we analyzed changes over time in survival and major neurosensory impairment in a sample of extremely low birth weight infants born between July 1, 1979, and June 30, 1994. METHODS: The study sample included 513 infants with birth weights of 501 to 800 g who were cared for in either of the two neonatal intensive care units that serve a 17-county region in northwest North Carolina and who were born to mothers residing in that region. At 1 year of age (corrected for gestation), survivors were examined by a pediatrician and were tested using the Bayley Scales of Infant Development. Major neurosensory impairment was defined as cerebral palsy, a Bayley Mental Developmental Index <68, or blindness. A total of 209/216 (97%) of survivors were examined at 1 year of age. Epoch of birth was defined as follows: epoch 1, July 1, 1979 to June 30, 1984; epoch 2, July 1, 1984 to June 30, 1989; and epoch 3, July 1, 1989 to June 30, 1994. RESULTS: Survival rates for epochs 1, 2, and 3 were, respectively, 24/120 (20%), 63/175 (36%), and 129/218 (59%). In contrast, the proportions with a major neurosensory impairment did not increase over time; rates for successive epochs were 6/24 (25%), 17/61 (28%), and 26/124 (21%). Rates of cerebral palsy were 3/24 (13%), 12/61 (20%), and 9/124 (7%); rates of delayed mental development were 4/24 (17%), 12/61 (20%), and 17/124 (14%); and rates of blindness were 2/24 (8%), 0/62, and 5/124 (4%), respectively. CONCLUSIONS: This analysis suggests that the increasing survival of extremely low birth weight neonates since the late 1970s has not resulted in an increased rate of major developmental problems identifiable at 1 year of age. 相似文献