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981.
982.
Normal human peripheral blood lymphocytes (PBL) are incapable of eliciting a significant murine cytotoxic T cell (CTL) response either in vivo or in vitro. However, using a primary in vivo and secondary in vitro stimulation with lectin-activated PBL, Thy-l-positive cytotoxic cells were produced. The antigens that these T-cells identified were independent of the serum source employed in the culture medium used for lectin activation. The cells always preferentially lysed cells from the immunizing individual but were also able to lyse target cells from unrelated individuals, regardless of HLA identity or disparity with the immunizing individual, suggesting the presence of both a private (possibly class II antigens) and public specificity. Using the lymphoblasts of different family members as immunogen and targets there was slight preference of the CTL for HLA-identical targets with no apparent difference between the lysis exhibited against semiidentical and nonidentical subjects. Monoclonal antibodies directed against HLA DR or beta 2-microglobulin failed to inhibit the cytotoxicity observed in these experiments. It is suggested that under these circumstances of xenogeneic education, non-MHC-restricted T cells may become cytotoxic, and this model may serve as a useful probe to investigate some of the less-well-defined aspects of the T cell repertoire. 相似文献
983.
Recently, enucleation of choroidal melanomas tends to be replaced by less radical treatments such as photocoagulation. Use of Ruthenium 106 plaques has proved to be efficient in Germany. Because the Beta rays of Ruthenium 106 have only limited tissue penetration they are used only for tumors of less than 6-7 mm thickness and less than 18 mm2 surface. This report describes 62 cases of choroidal melanomas treated with Ruthenium 106. With a follow-up period of 12 to 48 months, 32 cases had total regression, including 2 cases with metastases. 15 patients required a second procedue and 15 had additional photocoagulation. In 23 of 51 patients the visual acuity remained unchanged. In 26 patients the visual acuity decreased and 2 patients had an improvement. 13 patients with melanomas inside or close to the macular area decreased their visual acuity. 相似文献
984.
Determination of S-phenylmercapturic acid in the urine--an improvement in the biological monitoring of benzene exposure 总被引:3,自引:0,他引:3
Stommel P.; Muller G.; Stucker W.; Verkoyen C.; Schobel S.; Norpoth K. 《Carcinogenesis》1989,10(2):279-282
In an inhalation study rats were exposed to different dosesof benzene, ranging from 1 to 500 p.p.m. The urine was sampledduring the inhalation period of 8 h and for 24 h after exposure.S-Phenylmercapturic acid (S-PMA) in the urine was determinedby amino acid analysis. Phenol was measured by gas chromatography/massspectrometry. In both cases the correlation between benzeneuptake and the excretion of the urinary metabolites was significantat the level of P = 0.01. The same significant correlation (P= 0.01) was demonstrable after i.p. administration of benzeneat doses between 0.7 and 140.0 µI/kg body weight. In thecase of two collectives of workers who were exposed to air concentrationsof up to 0.15 p.p.m. for 8 h and of up to 1.13 p.p.m. for 12h respectively, the amount of S-PMA in the first urine samplesafter the shift was significantly higher than in samples collectedat the beginning of the shift (P = 0.01). In the first collectivethe mean values and the standard deviations of the S-PMA concentrationsin the samples at the beginning of the shift were 12.0 ±16.7 compared with 48.5 ± 64.5 µg/g creatinineat shift end. In the second collective they were 25.1 ±25.1 compared with 70.9 ± 109.2 µg/g creatinine.The level of significance of the difference between the concentrationvalues of S-PMA at the beginning and end of the shift was P= 0.01. The phenol concentration did not differ significantly.These results suggest that S-PMA can be regarded as a usefulindicator for monitoring individuals and collectives exposedto benzene at levels even <1 p.p.m. 相似文献
985.
986.
B. Laugner A. Muller J.B. Thibaut J.M. Farcot 《Annales fran?aises d'anesthèsie et de rèanimation》1985,4(6)
The use of intraspinal narcotics has been widely accepted as pain relief treatment for intractable cancer pain. Intraspinal low doses of morphine induce a potent selective long lasting analgesia. To avoid repetitive lumbar puncture, a drug delivery device was surgically implanted in 41 patients. The surgical procedure is described. The mean amout of morphine needed was 1.48±0.25 mg per day at time of surgery, rising to 6.86±1.47 mg per day after a mean survival time of 65 days. Tolerance became a major problem in 18 patients, which nearly all were selected at a late disease stage and previously received narcotics for pain relief. However, no clear-cut prognostic factor had a predictive value for the appearance of tolerance. In some cases, it could be successfully treated by intraspinal injection of local anaesthetics or clonidine. CSF leakage was noted in 11 patients; this was a challenge for us, as no other authors reported such a high rate for this complication. Aseptic meningitis was noted three times. In all cases but one, the symptoms resolved with appropriate treatment. 相似文献
987.
Serum vitamin E levels and red cell haemolysis were measured in 17 children with biliary obstruction after oral and intramuscular loading tests, and during long-term oral administration of differing doses of a fat-soluble and water-miscible preparation of alpha-tocopheryl acetate. The results suggested a severe defect in the intestinal absorption of both preparations. In three of the children who were studied during periods of improving biliary obstruction, absorption was shown to have improved. Bile plays a major role in the absorption of vitamin E from the intestinal tract and the exact mechanism of its action requires further elucidation. 相似文献
988.
989.
990.
D Bougle F Bureau P Foucault J F Duhamel G Muller M Drosdowsky 《The American journal of clinical nutrition》1988,48(3):652-654
To assess the molybdenum supply and requirements of preterm infants, Mo concentration was determined in milk from mothers of 6 term and 11 preterm newborns; no difference was found between fore- and hindmilk and no diurnal variations were found during 24-h collections. Respective values (means +/- SD) of term and preterm milks were 10.2 +/- 3.7 and 4.0 +/- 3.7 micrograms/L (106.2 +/- 38.5 and 41.7 +/- 38.5 nmol/L) at 3-5 d of lactation, 4.8 +/- 3.9 and 3.7 +/- 3.8 micrograms/L (50.0 +/- 4.6 and 38.5 +/- 39.6 nmol/L) at 7-10 d, 1.5 +/- 1.4 and 1.4 +/- 0.9 micrograms/L (15.6 +/- 14.6 and 14.6 +/- 9.6 nmol/L) at 14 d, 2.6 +/- 2.2 and 1.9 +/- 1.4 micrograms/L (27.1 +/- 22.9 and 19.8 +/- 14.6 nmol/L) at 1 mo, and 0.2 and 1.2 +/- 0.5 micrograms/L (2.1 and 12.5 +/- 5.2 nmol/L) at 2 mo. A statistical difference was found between term and preterm milk at 3-5 d of lactation. During lactation significant changes were found between the periods 3-5 d and 7-10 d, 14 d, 1 mo (p less than 0.01) and 2 mo (p less than 0.05) of lactation and between 7-10 d and 14 d (p less than 0.05). According to the requirements of the preterm infant, a supplementation of 2-3 micrograms.kg-1.d-1 by enteral route is suggested. 相似文献