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61.
Mikhail Kalinichev Keith W Easterling Stephen G Holtzman 《Neuropsychopharmacology》2003,28(2):317-328
Daily postpartum separations from the litter produce enduring changes in anxiety and sensitivity to the antinociceptive effects of morphine in Long-Evans dams. We tested whether postpartum experience alters sensitivity to the effects of morphine on locomotor activity. Dams were tested 4-6 weeks after their pups were weaned, and had one of the following backgrounds: daily separation from the litter on postpartum days 2-14 for either 3 h (prolonged separation-LS) or 15 min (brief separation-BS), or no separation (nonhandled control-NH). After 2 consecutive days (B1-2) of baseline activity measurements, subjects were tested daily after s.c. injections of either morphine (10 mg/kg) or saline for 7 days and again on day 10. Beginning 5 days later, saline and 1.0-10 mg/kg of morphine were tested in all dams. On B1, LS and BS dams habituated slower than NH controls, yielding higher horizontal counts. LS dams failed to habituate across baseline days and were more active than other dams on B2. Sensitization, a progressive increase in horizontal activity, was more rapid and robust in LS and BS dams compared to NH animals. LS was the only group that developed tolerance to morphine-induced decreases in vertical activity. In LS dams with the history of morphine treatment, injection of saline resulted in higher horizontal activity and center time compared to saline-treated counterparts, indicative of conditioning. Among animals with a history of saline treatment, LS dams were more sensitive to morphine challenges than BS and NH dams. As a result of the robust and long-lasting increases in the ability of morphine to induce behavioral sensitization in litter-separated dams, periodic postpartum separation may represent a new animal model of increased vulnerability to substance abuse. 相似文献
62.
The random dot stereogram E (RDE) has been shown to be a simple and effective test for the detection of binocular abnormalities and defective visual acuity in children. We determined the validity of the RDE as a screening test for reduced visual acuity, amblyopia and strabismus in two separate populations of children.
A nonselective group of 100 school children (aged 5 to 15 years) who presented consecutively to the ophthalmology department at Auckland Public Hospital were tested with the RDE. All cases of amblyopia and strabismus were detected by the RDE. Similar screening with the RDE test of 168 preschool children (aged three to four years) in the community resulted in an unacceptably high over-referral rate. The test was unreliable in the preschool age group because of difficulty in distinguishing between test failure and non-cooperation with the test. The low positive predictive value of the test in the younger age group suggests the test to be unsuitable for preschool vision screening. 相似文献
A nonselective group of 100 school children (aged 5 to 15 years) who presented consecutively to the ophthalmology department at Auckland Public Hospital were tested with the RDE. All cases of amblyopia and strabismus were detected by the RDE. Similar screening with the RDE test of 168 preschool children (aged three to four years) in the community resulted in an unacceptably high over-referral rate. The test was unreliable in the preschool age group because of difficulty in distinguishing between test failure and non-cooperation with the test. The low positive predictive value of the test in the younger age group suggests the test to be unsuitable for preschool vision screening. 相似文献
63.
64.
Screening for psychiatric illness in general practice: the general practitioner versus the screening questionnaire 总被引:9,自引:6,他引:3 下载免费PDF全文
This study compares the characteristics of general practitioners and a pen and paper test in the detection of psychiatric disorder in primary care settings. A psychiatrist interviewed a stratified sample of 283 patients drawn from 590 consecutive new illnesses seen in 15 general practices. Research diagnoses could be made in between one-quarter and one-third of the consecutive new illnesses. Two different research diagnostic systems agreed quite well with one another about who should be regarded as a psychiatric 'case' - although agreement between them for individual diagnoses was less impressive. Research diagnoses of psychiatric illnesses could be made in approximately 30% of new episodes of illnesses seen. If the DSM-3 system was used as a criterion of 'caseness', the specificity of the general health questionnaire was 75.4%, and the sensitivity was 87.1%. The general practitioners had fewer false positives than the questionnaire, but they were much more likely to miss psychiatric cases. Use of the general health questionnaire could increase their sensitivity from about 50% to 95%. 相似文献
65.
Peripheral and central injections of recombinant human interleukin-1β (IL-1β) have been shown to decrease social exploration and to induce body weight loss in rats. To characterize the receptor mechanisms of these effects, we used as a tool a specific antagonist of the receptors of IL-1, IL-1ra. Intraperitoneal (i.p.) administration of IL-1ra (8 mg/kg) blocked the effect of i.p. injection of IL-1β (4 μg/rat) on social behaviour but not on body weight. Central administration of IL-1ra (60 μg/rat, i.c.v.) abrogated the effects of centrally administered IL-1β (30 ngn/rat, i.c.v.) on both social behaviour and body weight. Central injection of IL-1ra (4 μg/rat, i.c.v.) also attenuated the effects of i.p. administered IL-1β (4 μg/rat) on social behaviour but not on body weight. These results suggest that the effects of IL-1β on social behavior are mediated centrally and that its effect on the loss of body weight involves different receptor mechanisms. 相似文献
66.
Summary. The present study was carried out to investigate the predictive value of the percentage of sperm motility after 24-h incubation and sperm survival ratio from semen and inseminated sperm suspension using grading of motility by WHO criteria with respect to the fertilization of oocytes in vitro. A total of 789 oocytes from 85 cases were inseminated and the mean fertilization rate obtained was 72.5%. There was no significant correlation between all of the sperm motility results with fertilization rate in vitro. All sperm motility results were not significantly different between the non-fertilizing group and the fertilizing group and also between the group of fertilization rate ≤ 25th percentile (fertilization rate ≤62.5%) and the group of fertilization rate >62.5%. However, the initial percentage of rapid progressive sperm motility and progressive motility in semen and inseminated sperm suspension at 24 h gave significant differences between the group of fertilization ≤ 50th percentile (fertilization rate ≤80%) and the group of fertilization rate >80%. Overall accuracy using these parameters for prediction of fertilization rate >80% was only about 60%. In conclusion, the percentage of sperm motility at 24 h and sperm survival ratio in both semen and inseminated sperm suspension have no practical value in predicting fertilization rate in vitro. Moreover, detailed motility grading cannot improve the predictivity of these sperm motility parameters. 相似文献
67.
68.
Keith D. Allen William J. Warzak Nancy G. Greger Toni D. Bernotas Carol A. Huseman 《Children's Health Care》1993,22(1):61-72
Fifty-six children with isolated growth hormone deficiency (IGHD) and their families completed self-report instruments about behavioral, social, and emotional adjustment of the children. Results show that children with IGHD may experience significant behavioral and social adjustment problems. Social and emotional adjustment was best predicted by the relative height discrepancy between an individual and their normal-sized peers. Adjustment varied depending on the type of adjustment under consideration, the relative height discrepancy of the individual, the age and gender of the child, and the amount of time in treatment. Discussion addresses the need for an interdisciplinary approach to effective patient management of children with IGHD. 相似文献
69.
70.
Hardwick M Cavalli LR Barlow KD Haddad BR Papadopoulos V 《Cancer Genetics and Cytogenetics》2002,139(1):48-51
Recent studies using human breast cancer cell lines, animal models, and human tissue biopsies have suggested a close correlation between the expression of the peripheral-type benzodiazepine receptor (PBR) and the progression of breast cancer. This study investigates the genetic status of the PBR gene in two human breast cancer cell lines: MDA-MB-231 cells, which are an aggressive breast cancer cell line that contains high levels of PBR, and MCF-7 cells, which are a nonaggressive cell line that contains low levels of PBR. Both DNA (Southern) blot and fluorescence in situ hybridization analyses indicate that the PBR gene is amplified in MDA-MB-231 relative to MCF-7 cells. These data suggest that PBR gene amplification may be an important indicator of breast cancer progression. 相似文献