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121.
R E Dahl N D Ryan B Birmaher M al-Shabbout D E Williamson M Neidig B Nelson J Puig-Antich 《Psychiatry research》1991,38(2):201-214
Two nights of electroencephalographic (EEG) sleep recording were performed in a group of prepubertal subjects with major depressive disorder (MDD) (n = 36, mean age = 10.4, SD = 1.5) and age-matched normal control children (n = 18, mean age = 10.1, SD = 1.6). All subjects were medically healthy and free of medications at the time of the study. There were no significant group differences for any major sleep variable after the initial adaptation night in this study. One subgroup of MDD subjects (n = 8) showed reduced REM latency on both recording nights, decreased stage 4 sleep, and increased REM time; this subgroup had significantly higher severity scores for depression but did not otherwise appear to be clinically distinct from the rest of the MDD subjects. Overall, the results indicate that the EEG sleep changes associated with depression in adults occurred less frequently in prepubertal MDD subjects. 相似文献
122.
P Nicotera M Rundgren D J Porubek I Cotgreave P Moldéus S Orrenius S D Nelson 《Chemical research in toxicology》1989,2(1):46-50
The cytotoxicity of acetaminophen (paracetamol) has been shown to be associated with a disruption of intracellular Ca2+ homeostasis caused by the interaction of its metabolite N-acetyl-p-benzoquinone imine (NAPQI) with hepatocyte thiols [Moore, M., et al. (1985) J. Biol. Chem. 260, 13035-13040]. Inasmuch as NAPQI can both covalently bind to thiols and oxidize thiols, we investigated the effects of two dimethylated analogues of NAPQI, one of which (2,6-dimethyl-NAPQI) primarily binds to thiols and the other of which (3,5-dimethyl-NAPQI) primarily oxidizes thiols. Of the three compounds, 2,6-dimethyl-NAPQI decreased protein thiols to the greatest extent and also inhibited hepatocyte plasma membrane Ca(2+)-ATPase to the greatest extent. The 3,5-dimethylated analogue decreased protein thiols to the least extent and inhibited the plasma membrane Ca(2+)-ATPase to a lesser extent. The cytotoxicity of all three compounds was preceded by a sustained elevation in cytosolic Ca2+ as compared to the transient rise caused by the alpha-agonist phenylephrine. Again, the 2,6-dimethyl analogue was the most potent of the three compounds. The thiol reagent dithiothreitol (DTT), which reversed the inhibition of the Ca(2+)-ATPase and the rise in cytosolic Ca2+, also protected against cytotoxicity. Agents that are known to inhibit either Ca(2+)-dependent proteases or phospholipases significantly delayed the onset of cytotoxicity caused by NAPQI and its analogues. Our results suggest that both arylation and oxidation of protein thiols may result in the elevation of cytosolic Ca2+ and in cytotoxicity and that arylation of critical thiol groups appears to be the more lethal reaction. 相似文献
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125.
Differences in preconceptional and prenatal behaviors in women with intended and unintended pregnancies. 总被引:6,自引:0,他引:6 下载免费PDF全文
W L Hellerstedt P L Pirie H A Lando S J Curry C M McBride L C Grothaus J C Nelson 《American journal of public health》1998,88(4):663-666
OBJECTIVES: This study examined whether pregnancy intention was associated with cigarette smoking, alcohol drinking, use of vitamins, and consumption of caffeinated drinks prior to pregnancy and in early pregnancy. METHODS: Data from a telephone survey of 7174 pregnant women were analyzed. RESULTS: In comparison with women whose pregnancies were intended, women with unintended pregnancies were more likely to report cigarette smoking and less likely to report daily vitamin use. Women with unintended pregnancies were also less likely to decrease consumption of caffeinated beverages or increase daily vitamin use. CONCLUSIONS: Pregnancy intention was associated with health behaviors, prior to pregnancy and in early pregnancy, that may influence pregnancy course and birth outcomes. 相似文献
126.
The objective of this study was to determine retrospectively the prevalence of osteoporosis in a referral population and to compare the effectiveness of measuring multiple skeletal sites for identifying osteoporosis. Although osteoporosis is considered to be a major public health problem in the United States, and there are reliable methods for diagnosis based on bone densitometry, fewer than 25% of cases are currently identified. There is no consensus about which skeletal site(s) should be measured for optimal results. In this study, bone mineral density (BMD) was measured by dual energy X-ray absorptiometry (DXA) at the radius (proximal site), lumbar spine, femoral neck, and total proximal femur regions in 537 consecutive white females age 50 and older referred by community physicians for bone densitometry. The prevalence of osteopenia and osteoporosis (based on the World Health Organization definitions) was determined, as well as the incidence of misclassification of patients based on different skeletal sites. Overall, 53.3% had osteoporosis, an additional 37.7% had osteopenia, and only 8.7% had normal BMD at all measurement sites. The prevalence was similar at all measurement sites and the incidence of misclassification was low. Given the magnitude of undetected osteoporosis and the efficacy of bone densitometry at any skeletal site, these data have important implications for the optimal deployment of bone density measurement facilities. 相似文献
127.
Gregory E Demas Randy J Nelson Bruce K Krueger Paul J Yarowsky 《Behavioural brain research》1998,90(2):199-201
To evaluate the cognitive phenotype of the segmental trisomy 16 (Ts65Dn) mouse, a model of Down Syndrome (DS, trisomy 21), we assessed spatial working and reference memory using a 12-arm radial maze (RAM). Ts65Dn mice made a greater number of reference memory errors across trials compared to control mice. Both genotypes showed improvement across trials, although improvement was slower in Ts65Dn mice. Ts65Dn mice also made a greater number of working memory errors on the RAM, and in contrast to control mice, did not improve across trials, always performing at near-chance levels. These results provide evidence for both spatial working and reference memory deficits in Ts65Dn mice, characteristics of cognitive dysfunction. 相似文献
128.
Reproduction stops among the majority of prairie voles (Microtus ochrogaster) during the winter. Short day lengths suppress male reproductive function dramatically in the laboratory, but photoperiod exerts only subtle effects on female reproductive function. Thus, the regulation of seasonal breeding in this species remains partially unspecified. In contrast to commonly studied rodents, female prairie voles do not undergo spontaneous estrous cycles; rather, they are induced into estrus by exposure to chemosignals expressed in conspecific male urine. In the present study, the hypothesis was tested that seasonal breeding among female prairie voles in the field reflects photoperiod-mediated changes in the responsiveness of the chemosensory system to male urine. Responsiveness was assessed by localizing the product of the c-fos immediate early gene with an immunocytochemical procedure. Female prairie voles were maintained in either long (LD 16:8) or short (LD 8:16) photoperiods from birth until adulthood, and exposed to either male urine or skim milk. Immunocytochemistry forfos protein revealed an increased number of immunoreactive cells within the accessory olfactory system of female prairie voles, including the accessory olfactory bulbs, granule cell layer, as well as the medial and cortical divisions of the amygdala 1 h after exposure to a single drop of urine as compared to individuals exposed to skim milk. The number of immunoreactivefos cells induced in females by conspecific male urine was also affected by photoperiod; short day females displayed fewer immunoreactivefos neurons in the accessory olfactory system as compared to long-day animal. Taken together, these results indicate that similar mechanisms underlie the responses of different rodent species to the chemosignals of conspecifics and that the pattern offos expression observed in the present study has functional significance for the regulation of reproduction in prairie voles. 相似文献
129.
Management of sacral and perineal defects following abdominoperineal resection and radiation with transpelvic muscle flaps 总被引:6,自引:2,他引:4
Scott J. Loessin M.D. Dr. N. Bradly Meland M.D. Richard M. Devine M.D. Bruce G. Wolff M.D. Heidi Nelson M.D. Horst Zincke M.D. 《Diseases of the colon and rectum》1995,38(9):940-945
PURPOSES: In this study we present our experience with treating persistent sacral and perineal defects secondary to radiation and abdominoperineal resection with or without sacrectomy. METHODS: Fifteen consecutive patients were treated with an inferiorly based transpelvic rectus abdominis muscle or musculocutaneous flap. RESULTS: Fourteen of the 15 patients achieved healing, and 7 patients had no complications. The remaining eight patients required one or more operative debridements and/or prolonged wound care to accomplish a healed wound. Our technique for the dissection and insetting of the transpelvic muscle flap is presented. CONCLUSION: The difficult postirradiated perineal and sacral wounds can be healed with persistent surgical attention to adequate debridement, control of infections, and a well-vascularized muscle flap. The most satisfying aspects for patients are the discontinuance of foul-smelling discharge, discontinuation of multiple, daily dressing changes, and reduction in the degree of chronic pain.Read at the meeting of the Midwestern Association of Plastic Surgeons, Bismarck, North Dakota, June 15 to 18, 1992. 相似文献
130.
One hundred patients with cirrhosis underwent abdominal computed tomography (CT) using a delayed contrast technique to determine liver and spleen volume. These scans were reviewed to screen this "at risk" population for hepatocellular carcinoma (HCC). Fifteen of the 100 screened patients had focal abnormalities suspicious for HCC. On biopsy, only 1 patient was shown to have HCC. The other 14 patients had either fatty infiltration or focal regeneration. In the same time interval, a total of 10 patients had histologically proven HCC. All presented with symptoms and died within 4 months of diagnosis. The results show that focal hepatic lesions can be detected by CT but in this population the lesions may not be due to HCC. The incidence of HCC was approximately 1%, probably reflecting a truly low incidence in this population. 相似文献