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991.
Evans AJ Fayaz I Cusimano MD Laperriere N Bilbao JM 《Archives of pathology & laboratory medicine》2000,124(11):1707-1709
Combined pleomorphic xanthoastrocytoma-ganglioma is a rare neoplasm, occurring in patients younger than 30 years. The clinical course of these tumors is difficult to predict because of their rarity. We report a case of combined pleomorphic xanthoastrocytoma-ganglioma that, in addition to the patient's age, is unusual in several respects. The lesion was located in the cerebellar vermis of a 60-year-old man and was radiographically solid. Histologically, there was an admixture of markedly pleomorphic astrocytic cells and neoplastic ganglion cells, with permeation of the overlying leptomeninges and surrounding cerebellum. In addition, there was focal capillary endothelial proliferation. There was no necrosis, and mitotic activity was rare at 1 mitotic figure per 40 high-power fields. The patient underwent a near gross total resection and postoperative radiotherapy and remains well through 16 months of follow-up. 相似文献
992.
Chen L Chen MH Larson MG Evans J Benjamin EJ Levy D 《The American journal of cardiology》2000,85(10):1189-1193
The epidemiology of syncope has not been well described. Prior studies have examined risk factors for syncope in hospital-based or other acute or long-term care settings. To determine risk factors for syncope in a community-based sample, we performed a nested case-control study. We examined reports of syncope in Framingham Heart Study participants who underwent routine clinic visits from 1971 to 1990. For each syncope case (n = 543) 2 controls were matched for age, sex, and examination period. Mean age of subjects was 67 years (range 25 to 95); 59% were women. History of stroke or transient ischemic attack, history of myocardial infarction, high blood pressure, use of antihypertensive medication, use of other cardiac medication, smoking, alcohol intake, body mass index, systolic blood pressure, diastolic blood pressure, heart rate, atrial fibrillation, PR interval prolongation, interventricular block, and diabetes or elevated glucose level were examined as potential predictors. Using conditional logistic regression analysis, the predictors of syncope included a history of stroke or transient ischemic attack (odds ratio [OR] 2.56, 95% confidence interval [CI] 1.62 to 4.04), use of cardiac medication (OR 1.67, 95% CI 1.21 to 2. 30), and high blood pressure (OR 1.46, 95% CI 1.14 to 1.88). Lower body mass index was marginally associated with syncope (OR per 4 kg/m(2) decrement 1.10, 95% CI 0.99 to 1.22), as were increased alcohol intake (OR per 5 oz/week 1.11, 95% CI 0.99 to 1.26), and diabetes or an elevated glucose level (OR 1.29, 95% CI 0.96 to 1.75). To our knowledge, this study represents the first community-based study of risk factors for syncope. 相似文献
993.
Evans PT 《The American journal of medicine》2000,109(9):737, 742-737, 743
In those issues in which our regular Case of the Month does not appear, The Green Journal will present a Diagnostic Dilemma-an electrocardiogram or radiograph, or both, with a brief case history-as a challenge for our readers to solve. The correct answer appears on page 742. If you would like to contribute a Diagnostic Dilemma, please submit a high-quality copy of the ECG or radiograph with a brief synopsis (<250 words) of the case to editorial office of the American Journal of Medicine. 相似文献
994.
Evans T 《The American journal of medicine》2000,108(6):504, 512-504, 513
995.
Traumatic lumbar puncture at diagnosis adversely affects outcome in childhood acute lymphoblastic leukemia 总被引:7,自引:3,他引:4
Gajjar A Harrison PL Sandlund JT Rivera GK Ribeiro RC Rubnitz JE Razzouk B Relling MV Evans WE Boyett JM Pui CH 《Blood》2000,96(10):3381-3384
The effect of traumatic lumbar puncture at the time of initial diagnostic workup on treatment outcome in children with newly diagnosed acute lymphoblastic leukemia (ALL) was investigated. The findings of the first 2 lumbar punctures performed on 546 patients with newly diagnosed ALL treated on 2 consecutive front-line studies (1984-1991) at St Jude Children's Research Hospital were retrospectively reviewed. Lumbar punctures were performed at the time of diagnosis and again for the instillation of first intrathecal chemotherapy. The event-free survival (EFS) experience for patients with 1 cerebrospinal fluid (CSF) sample contaminated with blast cells was worse than that for patients with no contaminated CSF samples (P =.026); that of patients with 2 consecutive contaminated CSF samples was particularly poor (5-year EFS = 46 +/- 9%). In a Cox multiple regression analysis, the strongest prognostic indicator was 2 consecutive contaminated CSF samples, with a hazard ratio of 2.39 (95% confidence interval, 1. 36-4.20). These data indicate that contamination of CSF with circulating leukemic blast cells during diagnostic lumbar puncture can adversely affect the treatment outcome of children with ALL and is an indication to intensify intrathecal therapy. 相似文献
996.
This work was undertaken to investigate two systems for producing light-cured earmoulds, in order to evaluate the factors which influence the efficacy of such procedures. It was shown that there were variations in light intensity in the light boxes, and that the depth and age of gel in which curing takes place was important. Degree of cure of the materials was assessed by hardness measurements for hard materials and resistance to tearing for hard materials. Light-cured technology has great potential for the rapid production of earmoulds. 相似文献
997.
Sterling DA Lewis RD Serrano F Dugbatey K Evans RG Sterling LS 《Applied occupational and environmental hygiene》2000,15(2):217-227
An environmental-justice (equity) grant program was used to make accessible an existing lead-training program to minority persons and residents of low-income communities. The purpose of the program was to enhance the knowledge base within the communities concerning lead hazards and intervention strategies and expand possibilities for employment in the lead abatement industry. Barriers to attendance were anticipated and addressed, and included transportation, meals, license application fees, reminders of course date and location, and day care. The program was evaluated through measures of recruitment rates, pre- and post-testing scores, and change in perception of confidence at pre-test, post-test, and at four-month follow-up. Fee-paying registrants over the same time period were used as a comparison group. First day attendance rates for individuals recruited into the equity-grant was 59 percent, of these 94 percent completed all days. Equity and fee-paying groups had similar scores on the pre-test (p = .209), while mean scores on the final exam differed significantly (p < .001) between the groups and were 77 percent and 85 percent, respectively. After adjusting for demographic and course type attended, perceptions of self-efficacy (benefit) and outcome-effectiveness (confidence) increased significantly from pre- to post-tests for both groups and remained at post-course levels at four months follow-up. Lessons learned include: (1) Lead abatement and other related activities can be successfully taught through traditional training methods; (2) A necessary element for delivery of educational services to minority groups is forming workable ties with local community groups, but eligibility requirements must be maintained; (3) Once barriers to first-day attendance are overcome, the information necessary to perform specific work skills can be taught; (4) Positive changes in belief are not dependent on minority status, income, or education levels; (5) Training and education increased confidence in ability to perform learned skills, and belief that there will be a beneficial outcome when performed for themselves, their families, and communities; and, (6) A consensus regarding applicability of regulations must be achieved among federal, state, and local communities. 相似文献
998.
999.
M I Evans A Greb L M Kunkel A J Sacks M P Johnson C Boehm H H Kazazian E P Hoffman 《American journal of obstetrics and gynecology》1991,165(3):728-732
Deoxyribonucleic acid techniques can be used to diagnose Duchenne muscular dystrophy prenatally in male fetuses that are at risk. Deoxyribonucleic acid-based prenatal diagnosis can be impossible when there is only one prior affected male and there is no identifiable deletion or alteration. We performed fetal muscle biopsy in utero in such a case and documented the presence of dystrophin, thereby confirming normality in a male fetus at risk. This first in utero experience adds fetal muscle biopsy to the available procedures for fetal tissue diagnosis. 相似文献
1000.
Ultrasound evaluation of the fetus has become a vital part of prenatal care not only to detect abnormalities of fetal growth, but to diagnose congenital anomalies, hydatidiform mole and ectopic pregnancy, to assess fetal well-being, and finally to provide ultrasound guidance for invasive procedures. This article will discuss the role of fetal ultrasonography as we head into the 1990s, the changing concepts of indications for ultrasound scanning, the increasing sophistication of the technique, and the types of anomalies detected by this imaging method. 相似文献