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991.
J. Řeháček B. Kaaserer J. Úrvölgyi M. Lukáčová E. Kováčová E. Kocianová 《European journal of epidemiology》1994,10(6):719-723
Two strains ofCoxiella burnetii and two strains of an unidentified rickettsial organism were isolated for the first time fromIxodes ricinus ticks collected in the Alpine region of Tirol, Austria. TheC. burnetii strains belong to the group of agents causing acute forms of Q fever. The other two strains of isolated rickettsial agent share some antigenic epitopes withC. burnetii andR. prowazekii but they differ from them by their high sensitivity to freezing and refreezing and by poor multiplication in yolk sacs of chick embryos. There is at present no evidence that these organisms cause human illness and no ecological information is available. We suggest they may be some new species of rickettsiae or rickettsia-like organisms. 相似文献
992.
993.
脊柱侧弯患者呼吸功能减退的病因学至今尚无定论。力学因素很可能是呼吸功能减退的原因之一。通过比较脊柱则弯患者与下沉人深呼吸时胸段脊柱及胸廓三维运动来探讨力学因素对呼吸功能减退的影响。脊柱侧弯患者胸廓及脊柱骨架的僵直有可是影响呼吸动力学的原因之一。 相似文献
994.
Stimulation of neural afferents in the parietal pericardium of anaesthetized, open-chest dogs by local application of capsaicin (0.1-100 micrograms) consistently induced dose-related pressor effects and tachycardia, whereas the application (0.1-1 microgram) of neuropeptides substance P (SP), neurokinin A (NKA), neurokinin B (NKB) or calcitonin gene-related peptide (CGRP) had no cardiovascular effect. Capsaicin-induced reflex responses were not affected by vagotomy, but were abolished by bilateral sectioning of the upper thoracic (T1-T4) white rami communicantes and stellectomy. Capsaicin-induced reflex tachycardia could also be abolished by a beta-adrenoceptor blockade with propranolol (0.5 mg/kg, IV), while ganglionic blockade with pentolinium (0.5 mg/kg, IV) eliminated both the tachycardia and pressor effects. Intravenous treatment with the cyclo-oxygenase inhibitors, indomethacin (5 mg/kg) or aspirin (100 mg/kg) had no effect on reflex pressor and heart rate responses to pericardial capsaicin. Also local treatment of the pericardium with either indomethacin (1 microgram/ml) or dual cyclooxygenase/lipoxygenase inhibitor, BW755C (10 micrograms/ml) failed to affect the responses to capsaicin. We conclude that (i) capsaicin-sensitive afferents which are present in the dog pericardium have a spinal origin and can initiate sympathetically-mediated reflex cardiovascular changes; (ii) the reflexogenic action of capsaicin on pericardial afferents does not depend on local production of eicosanoids; (iii) neuropeptides appear to be without reflexogenic effects on neural afferents in the dog parietal pericardium. 相似文献
995.
Effect of transient hypoxia on sensitivity to doxorubicin in human and murine cell lines 总被引:2,自引:0,他引:2
C K Luk L Veinot-Drebot E Tjan I F Tannock 《Journal of the National Cancer Institute》1990,82(8):684-692
Overreplication of DNA associated with gene amplification and drug resistance has been reported to occur after transient hypoxia of rodent cells. Because oxygen levels fluctuate in solid tumors, clinical drug resistance might be stimulated by this mechanism. We have therefore studied the effect of transient hypoxia on sensitivity to doxorubicin in human and murine cell lines. Exposure to hypoxia led to a decreased rate of cell proliferation, and most of the observed changes in sensitivity to doxorubicin were consistent with cell cycle-dependent cytotoxicity of this drug. After transient hypoxia, about 10% of the murine cells (EMT6/Ro and KHT-LP1) contained greater than four times the haploid DNA content (greater than 4C DNA), but only 0%-5% of the human cells (MGH-U1, A549, and Hey) had greater than 4C DNA content. Murine cells that had been exposed to hypoxia and reoxygenation, and which had greater than 4C DNA content, were separated by flow cytometry. For KHT-LP1 cells, but not for EMT6/Ro cells, this subpopulation was found to be more resistant to doxorubicin than the subpopulation with less than 4C DNA content and the aerobic control. When resistant KHT-LP1 clones were expanded in the presence of doxorubicin, six of six clones showed amplification of the P-glycoprotein gene family. The ability and efficiency of hypoxia to induce DNA overreplication, gene amplification, and drug resistance appears to be cell-line dependent. 相似文献
996.
997.
Between 1975 and 1988 authors encountered 44 pregnancies in 26 women who had had chronic renal disease and unimpaired renal function before the conception. Complications during pregnancy and the outcome of pregnancy were studied. There were 5 spontaneous abortions between the 11th and 20th weeks of gestation, 1 therapeutic abortion, 3 still births at weeks 28, 32 and 33, 6 neonatal deaths at age of 26 to 35 weeks, 11 preterm newborns, 35 live births, 9 infants with intrauterine growth retardation including 4 preterm newborns and 1 fetal malformation and 2 cases with premature rupture of the fetal membranes. The pregnancies were complicated with anaemia in 23 cases, with urinary tract infection in 19, with hypertension in 16, with proteinuria in 12 and with edema in 11 cases. Increase in the serum creatinine value during pregnancy was found in 6 cases. These data indicate that the pregnancy in patients with chronic renal disease who had normal renal function before the planned conception, is accompanied with increased risk for both the mother and child. 相似文献
998.
Desmoid tumors--treatment and prognosis. 总被引:6,自引:0,他引:6
W M Wara T L Phillips D R Hill E Bovill K H Luk A S Lichter S A Leibel 《Radiology》1977,124(1):225-226
Desmoid tumors are locally invasive benign tumors arising from musculoaponeurotic structures which are classified as fibromatoses and which have generally high post-surgical recurrence rates. Sixteen patients with desmoid tumors were treated with irradiation and evaluated for 2 to 6 years post-treatment. Of the 16, 13 cases have been controlled without recurrence. Virtually complete resolution of the tumor mass has been accomplished without the disfigurement and dysfunction characteristic of the radical surgical approach to treatment. 相似文献
999.
Hürthle cell tumor behavior: dilemma and resolution 总被引:1,自引:0,他引:1
Thirty-four patients with the diagnosis of Hürthle cell tumor occurring from 1971 to 1984 were reviewed to help delineate an acceptable treatment policy. Twenty-nine of these occurred in the last 5 years of study so that extensive follow-up was not possible. Patients varied from age 17 years to 82 and consisted of five males and 29 females, most of whom had an asymptomatic solitary cold nodule. There was a 26% incidence of malignancy. One patient died of cancer caused by anaplastic change of underlying disease; this woman had refused surgery after an incisional biopsy specimen showed benign Hürthle cell tumor. Surgery consisting of lobectomy in 16 patients and near-total thyroidectomy in 18 was uncomplicated. No nodal surgery was necessary. Eighteen percent of patients had multicentric disease of which one half were malignant. Twelve percent of patients developed contralateral Hürthle cell tumor after lobectomy. Associated thyroid lesions occurred in 30% of patients, hyperparathyroidism in 10%. There are polar views in the literature on the management of these patients. While our own tumor experience has been reassuring, we feel that in view of the paucity of cases, those who view this tumor in a serious light deserve attention. Accordingly we advocate near-total thyroidectomy as a primary operation for those who are fit, lesser procedures for the disabled, and the difficult situation, and node sampling to detect early metastasis and improved survival in this group. It is apparent that further reporting of long-term follow-up experience is necessary for complete resolution of dilemmas in the treatment of this problem. 相似文献
1000.
The comparative results of treatment in idiopathic thoracolumbar and lumbar scoliosis using the Harrington, Dwyer, and Zielke instrumentations 总被引:5,自引:0,他引:5
Forty-five patients with idiopathic thoracolumbar or lumbar scoliosis were treated with the Harrington, Dwyer, or Zielke instrumentation and fusion. The Harrington group achieved a 55% correction of the primary curves, while the Dwyer and the Zielke groups achieved 88 and 91%, respectively. Overcorrection of the curves occurred in a total of nine cases in the latter two groups. The Dwyer and Zielke instrumentations enabled better correction of the curves with a shorter fusion. At subsequent follow-up, the 'adding on' phenomenon as a result of the shorter fusion in the Dwyer group was unchanged, while that in the Zielke group became gradually resolved. The Zielke instrumentation appears to be the apparatus of choice for treatment of thoracolumbar and lumbar scoliosis. 相似文献