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991.
BACKGROUND: Research has found that the elderly are the age group that is the least likely to engage in preventive health behaviors, even though these behaviors continue to benefit individuals throughout the life span. We investigated for the first time whether an age-specific factor, older individuals' beliefs about their own aging, predicts their likelihood of engaging in preventive health behaviors over time. METHODS: We conducted multivariate linear regression to test the predictive value of aging self-perceptions on the preventive health behaviors of 241 individuals, who participated in the Ohio Longitudinal Study of Aging and Retirement (OLSAR) aged 50-80 years old. The preventive health behaviors included eating a balanced diet, exercising, and following directions for taking prescribed medications. RESULTS: Individuals with more positive self-perceptions of aging tended to practice more preventive health behaviors over the next two decades after controlling for age, education, functional health, gender, self-rated health, and race (P = 0.032). CONCLUSIONS: Our findings suggest that addressing views about aging could help improve efforts to increase preventive health behaviors in the older population. 相似文献
992.
Lumbroso-Le Rouic L Charif Chefchaouni M Levy C Plancher C Dendale R Asselain B Solignac S Mazal A Desjardins L 《Eye (London, England)》2004,18(9):911-916
PURPOSE: To describe the results of 125I plaque brachytherapy of uveal melanomas anterior to the equator in terms of local control and the associated complications while trying to identify their risk factors (patients' demographic data, ocular, and tumour characteristics). METHODS: Retrospective analysis of a series of patients treated by 125I between 1990 and 2000 in a single institution. The main outcome measures are evaluation of local tumour control and complications associated with 125I plaque brachytherapy of these melanomas. RESULTS: During the study period, 136 patients were treated for an anterior tumour. The median follow-up was 62 months. The overall 5-year survival rate was 88.3%, the 5-year metastasis rate was 4% and the local recurrence rate was 1.5%. The mean final visual acuity was 20/40. The ocular complications most frequently observed at 5 years were cataract (50.3%), maculopathy (18.3%), intraocular inflammation (19.3%), and glaucoma (10.6%). Optic neuropathy, retinal detachment, keratitis, and intravitreous haemorrhage were also described. Risk factors for worse survival were age greater than 65 years and initial tumour thickness greater than 4 mm. Risk factors for the development of cataract were age more than 65 years old, male gender, and tumour diameter of more than 10 mm. Risk factors for intraocular inflammation were tumour thickness of more than 4 mm and invasion of the ciliary body. CONCLUSIONS: The use of 125I plaque brachytherapy to treat melanomas situated anterior to the equator allows good local and systemic control with a low rate of macular and optic disc complications. The most frequent complication was cataract formation. 相似文献
993.
994.
So PL Lee K Hebert J Walker P Lu Y Hwang J Kopelovich L Athar M Bickers D Aszterbaum M Epstein EH 《Cancer research》2004,64(13):4385-4389
Oral retinoids can reduce basal cell carcinoma (BCC) incidence in genetically susceptible patients, and one topical retinoid, tazarotene, has been reported to cure some sporadic BCCs. Therefore, we have tested whether this agent would affect BCCs in Ptch1+/- mice in a controlled chemoprevention trial. We found that topical tazarotene dramatically inhibits the formation of BCCs induced with either UV or ionizing radiation. The ability of tazarotene to inhibit BCC formation in this mouse model provides encouragement for the use of tazarotene in skin cancer chemoprevention trials in humans. 相似文献
995.
Inhibition of smoothened signaling prevents ultraviolet B-induced basal cell carcinomas through regulation of Fas expression and apoptosis 总被引:11,自引:0,他引:11
Athar M Li C Tang X Chi S Zhang X Kim AL Tyring SK Kopelovich L Hebert J Epstein EH Bickers DR Xie J 《Cancer research》2004,64(20):7545-7552
Abnormal activation of the hedgehog-signaling pathway is the pivotal abnormality driving the growth of basal cell carcinomas (BCCs), the most common type of human cancer. Antagonists of this pathway such as cyclopamine may therefore be useful for treatment of basal cell carcinomas and other hedgehog-driven tumors. We report here that chronic oral administration of cyclopamine dramatically reduces ( approximately 66%) UVB induced basal cell carcinoma formation in Ptch1(+/-) mice. Fas expression is low in human and murine basal cell carcinomas but is up-regulated in the presence of the smoothened (SMO) antagonist, cyclopamine, both in vitro in the mouse basal cell carcinoma cell line ASZ001 and in vivo after acute treatment of mice with basal cell carcinomas. This parallels an elevated rate of apoptosis. Conversely, expression of activated SMO in C3H10T1/2 cells inhibits Fas expression. Fas/Fas ligand interactions are necessary for cyclopamine-mediated apoptosis in these cells, a process involving caspase-8 activation. Our data provide strong evidence that cyclopamine and perhaps other SMO antagonists are potent in vivo inhibitors of UVB-induced basal cell carcinomas in Ptch1(+/-) mice and likely in humans because the majority of human basal cell carcinomas manifest mutations in PTCH1 and that a major mechanism of their inhibitory effect is through up-regulation of Fas, which augments apoptosis. 相似文献
996.
Chronowski GM Wilder RB Levy LB Atkinson EN Ha CS Hagemeister FB Barista I Rodriguez MA Sarris AH Hess MA Cabanillas F Cox JD 《American journal of clinical oncology》2004,27(1):73-80
The purpose of this preliminary study was to determine the incidence of second malignancies after combined-modality therapy for adults with Hodgkin disease and relate it to the details of initial treatment. We retrospectively studied 286 patients ranging in age from 16 to 88 years with stage I or II Hodgkin disease who were treated between 1980 and 1995 with chemotherapy followed 3 to 4 weeks later by radiotherapy. Patients received a median of three cycles of induction chemotherapy. Mitoxantrone, vincristine, vinblastine, and prednisone was used in 161 cases, mechlorethamine, vincristine, procarbazine, and prednisone (MOPP) in 67 cases, Adriamycin, bleomycin, vinblastine, and dacarbazine in 19 cases, lomustine, vinblastine, procarbazine, and prednisone/doxorubicin, bleomycin, dacarbazine, and lomustine in 18 cases, and other chemotherapeutic regimens in the remaining 21 cases. The median radiotherapy dose was 40 Gy given in 20 daily 2-Gy fractions. Median follow-up of surviving patients was 7.4 years. There were 2,230 person-years of observation. Significantly increased relative risks (RR) were observed for acute myeloid leukemia (RR, 69.3; 95% CI, 14.3-202.6) and melanoma (RR, 7.3; 95% CI, 1.5-21.3). The 5-, 10-, and 15-year actuarial risks of acute myeloid leukemia were 0.8%, 1.3%, and 1.3%, respectively. Patients treated with MOPP had the highest 15-year actuarial risk of leukemia (1.6%). The 5-, 10-, and 15-year actuarial risks of solid tumors were 1.9%, 9.3%, and 16.8%, respectively. Consolidative radiotherapy to both sides of the diaphragm resulted in a trend toward an increased risk of solid tumors relative to radiotherapy to only one side of the diaphragm (p = 0.08). In an effort to reduce the risk of second malignancies, we have stopped using the alkylating agents nitrogen mustard and procarbazine and elective paraaortic and splenic radiotherapy after chemotherapy. 相似文献
997.
Slater JD Rossi CJ Yonemoto LT Bush DA Jabola BR Levy RP Grove RI Preston W Slater JM 《International journal of radiation oncology, biology, physics》2004,59(2):348-352
PURPOSE: We analyzed results of conformal proton radiation therapy for localized prostate cancer, with emphasis on biochemical freedom from relapse. METHODS AND MATERIALS: Analyses were performed for 1255 patients treated between October 1991 and December 1997. Outcomes were measured on primarily in terms of biochemical relapse and toxicity. RESULTS: The overall biochemical disease-free survival rate was 73%, and was 90% in patients with initial PSA 相似文献
998.
Clinical implications of quantification of mesorectal tumor invasion by endoscopic ultrasound: All T3 rectal cancers are not equal 总被引:1,自引:0,他引:1
Harewood GC Kumar KS Clain JE Levy MJ Nelson H 《Journal of gastroenterology and hepatology》2004,19(7):750-755
BACKGROUND: Depth of invasion beyond the muscularis propria (MP) by T3 rectal cancer can vary. The purpose of the present paper was to determine if depth of invasion beyond MP, as assessed by preoperative endoscopic ultrasound (EUS), can predict tumor recurrence in patients with T3 rectal tumors. METHODS: Patients with T3NxM0 rectal cancer, as determined by EUS, who underwent surgical resection (without preoperative neoadjuvant therapy) were reviewed by two blinded endosonographers. Tumors were classified as minimally invasive T3 (invasion = 2 mm beyond MP by EUS) and advanced T3 disease (invasion > 2 mm). RESULTS: Forty-two patients with T3 rectal tumors underwent surgical resection without receiving preoperative neoadjuvant therapy, of whom 14 had minimally invasive T3 and 28 had advanced T3 disease, as determined by preoperative EUS. Median follow up was 19 months. Tumor recurrence rates in minimally invasive and advanced T3 tumors were 14.3% and 39.3%, respectively, P = 0.02 (log-rank test). Adjusting for nodal status and postoperative adjuvant therapy administration, Cox proportional hazards model demonstrated advanced T3 disease (by EUS) to predict tumor recurrence, hazard ratio, 2.28 (95% confidence interval: 1.17-5.81), P = 0.01. CONCLUSIONS: All T3 rectal tumors are not equal, with minimally invasive disease carrying a more favorable prognosis. By discriminating minimally invasive from advanced T3 disease, preoperative EUS provides important prognostic information. Further subclassification of T3 tumors, based on preoperative EUS staging, should be considered to enhance selection of patients for neoadjuvant therapy. 相似文献
999.
1000.
Dremencov E Nahshoni E Levy D Mintz M Overstreet DH Weizman A Yadid G 《Neuroreport》2004,15(12):1983-1986
The Flinders sensitive line of rats is a widely accepted and validated model of depression. These rats demonstrate abnormalities in limbic dopamine neurotransmission, suggesting disturbed neuronal activity in the ventral tegmental area. Interspike interval time-series were recorded from the ventral tegmental area of control Sprague-Dawley and Flinder sensitive line rats. These data were analyzed using standard measures (mean firing rate, bursting activity and spectral analysis) as well as the pointwise correlation dimension, a nonlinear measurement characterizing the complexity degree of dynamic systems. Pointwise correlation dimension, but not standard analysis revealed a significant difference between the animal lines. Our results suggest that nonlinear analyses can detect dysregulation of the mesolimbic dopaminergic system and shed light on the pathophysiology of depression. 相似文献