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排序方式: 共有4745条查询结果,搜索用时 15 毫秒
941.
Jun Yu MD PhD Qian Tao PhD Yuen Y. Cheng PhD Kwan Y. Lee MS Simon S. M. Ng MD Kin F. Cheung MS Linwei Tian MD PhD Sun Y. Rha PhD Ulf Neumann MD PhD Christoph Röcken MD PhD Matthias P. A. Ebert MD PhD Francis K. L. Chan MD Joseph J. Y. Sung MD PhD 《Cancer》2009,115(1):49-60
BACKGROUND:
Abnormal activation of the Wnt/β‐catenin signaling pathway is common and critical in the pathogenesis of digestive cancers. In this study, the authors investigated the promoter methylation of the dickkopf homolog 3 gene Dkk‐3 in these cancers and its prognostic significance in gastric cancer.METHODS:
Dkk‐3 methylation was assessed in 173 patients with gastric cancers (including 104 patients who were followed for up to 4090 days) and in 128 patients with colorectal cancer. Cell growth was evaluated by using a colony‐formation assay. For survival analyses, the authors used Kaplan‐Meier plots, the log‐rank test, and Cox proportional regression.RESULTS:
Dkk‐3 was silenced or down‐regulated in 12 of 17 gastric cancer cell lines (70.6%) and in 3 of 9 colon cancer cell lines (33.3%). The loss of gene expression was associated with promoter methylation, which could be restored by demethylating agents. Ectopic expression of Dkk‐3 suppressed colony formation. Moreover, methylation of Dkk‐3 was detected in 117 of 173 primary gastric tumors (67.6%) and in 67 of 128 colorectal tumors (52.3%). The clinical significance and the prognostic value of Dkk‐3 methylation also were examined in 104 gastric cancers and in 84 colorectal cancers. Multivariate analysis indicated that Dkk‐3 methylation was associated significantly and independently with poor disease survival (relative risk, 2.534; 95% confidence interval, 1.54–4.17; P = .002) in gastric cancer, but not in colorectal cancer. Kaplan‐Meier survival curves revealed that patients who had Dkk‐3 methylated gastric cancers had a significantly shorter survival (median, 0.76 years) compared with patients who did not have Dkk‐3 methylation (median, 2.68 years; P < .0001; log‐rank test).CONCLUSIONS:
Epigenetic silencing of the Dkk‐3 gene by promoter methylation was a common event in gastric cancer and was associated with a poor outcome in such patients. Cancer 2009. © 2008 American Cancer Society. 相似文献942.
This study enhanced nutritional knowledge in an education program and encouraged healthy dietary habits and regular physical activity among teenagers. A total of 203 adolescents from a secondary school in Hong Kong took part in the study. Their Body Mass Index, dietary habits, and physical exercise pattern were recorded and examined before and after the health education program. The prevalence of overweight and obesity, together with the fat composition, were high among the participants before the nutrition education program. There was a marked gain in knowledge upon its completion. A follow-up action conducted 3 months later revealed positive outcomes in relation to the diet and physical activity level. The teenagers were able to take control of their health and requested the tuck shop to sell more healthy food and reduce the supply of unhealthy items. The educational initiatives in dietary habits and physical activities proved to be effective in encouraging the teenagers to eat more healthily and to adopt an active lifestyle. 相似文献
943.
BACKGROUND: This paper aims at presentation of our surgical techniques and results of the lateral thoracic (LT) flaps for head and neck reconstructions. METHOD: There were seven LT cutaneous, seven LT myocutaneous, and two LT conjoint myocutaneous flaps for reconstruction of head and neck mucosal or cutaneous defects. RESULTS: The largest flap size was 22 cm x 13 cm. All donor sites were closed primarily. The highest point of reconstruction was in the nasopharynx internally and zygoma externally. All flaps survived without major complication. CONCLUSIONS: The LT flap has the versatility of cutaneous, myocutaneous, and conjoint flaps with pectoralis major or latissimus dorsi myocutaneous flaps to reconstruct large surgical defects. It has a large, reliable surface area, a long pedicle to reach nasopharynx and zygoma, and has less bulky muscle to facilitate tubular reconstruction of circumferential pharyngeal defect, one-stage operation, esthetic hidden donor site scar in axillary region, and minimal donor site morbidity. It is an additional reliable pedicle flap in our armamentarium for reconstruction of both cutaneous and mucosal defects in the head and neck region. 相似文献
944.
945.
Yuen HK Cheuk W Cheng AC Anh C Chan N 《Ophthalmic plastic and reconstructive surgery》2007,23(1):70-72
A 72-year-old man presented with a 2-year history of epiphora. CT revealed an extensive inferomedial orbital tumor connected to the lacrimal sac and duct. Incisional biopsy revealed malignant oncocytoma of the lacrimal sac. The patient was treated with exenteration and maxillectomy followed by a course of postoperative radiotherapy. Patients with malignant oncocytoma may present with simple epiphora in absence of other signs and symptoms such as blood stained tearing or purulent rhinorrhea. 相似文献
946.
PURPOSE: To review the result of nonpenetrating deep sclerectomy (NPDS) combined with phacoemulsification in the treatment of chronic angle-closure glaucoma (CACG) with coexisting cataract. METHODS: This is a retrospective review of 29 eyes of 26 patients who had undergone combined NPDS and phacoemulsification for cataract and CACG between January 2001 and June 2003. The visual acuity, intraocular pressure (IOP), and complications were analyzed. RESULTS: The mean follow-up period was 33.8 months (range 23.3 to 54.0 months). Postoperative visual acuity improved in 21 eyes (72%) and remained the same in 6 eyes (21%). The IOP was reduced significantly from 20.3+/-3.9 mmHg (mean +/- SD) preoperatively to 15.9+/-3.1 mmHg postoperatively at last follow-up visit (p<0.001). The number of antiglaucoma medications was also reduced significantly from 2.9+/-0.8 (mean +/- SD) preoperatively to 1.0+/-1.2 at last follow-up (p<0.001). Fifteen eyes (52%) achieved complete success with IOP < or = 21 mmHg without antiglaucoma medications and 25 eyes (86%) achieved qualified success with IOP < or = 21 mmHg with or without medications at the last follow-up visit. Of the 25 eyes achieving qualified success, 24 (96%) had a reduction in the number of medications. There were 4 failures, defined as uncontrolled IOP requiring further filtering operation or oral drug treatment. Intraoperative complications included one accidental anterior chamber puncture and one iris plug intraoperatively. Postoperative complications included one choroidal effusion, three wound leaks requiring repair, and two punctate epithelial erosions. There was no shallowing of the anterior chamber, hyphema, hypotony, or infection encountered. CONCLUSIONS: Combined NPDS and phacoemulsification could be a safe and effective surgical option for the management of CACG with cataract. 相似文献
947.
948.
Rabeprazole-based 3-day and 7-day triple therapy vs. omeprazole-based 7-day triple therapy for the treatment of Helicobacter pylori infection 总被引:7,自引:0,他引:7
B. C. Y. Wong W. M. Wong Y. K. Yee W. K. Hung A. W. C. Yip M. L. Szeto K. F. Li P. Lau F. M. Y. Fung T. S. M. Tong K. C. Lai W. H. C. Hu M. F. Yuen C. K. Hui & S. K. Lam 《Alimentary pharmacology & therapeutics》2001,15(12):1959-1965
BACKGROUND: Rabeprazole is a new proton pump inhibitor with more potent acid suppressive and anti-Helicobacter effects. AIM: To compare two different regimens of rabeprazole-based triple therapy vs. 7-day omeprazole-based triple therapy for the eradication of Helicobacter pylori infection. METHOD: Patients with proven H. pylori infection were randomized to receive: (i) 7-day rabeprazole, 10 mg, amoxicillin, 1000 mg, and clarithromycin, 500 mg, all twice daily; (ii) 3-day rabeprazole, 20 mg, amoxicillin, 1000 mg, and clarithromycin, 500 mg, all twice daily; or (iii) 7-day omeprazole, 20 mg, amoxicillin, 1000 mg, and clarithromycin, 500 mg, all twice daily. Endoscopy (CLO test, histology) was performed before randomization and 6 weeks after drug treatment. RESULTS: One hundred and seventy-three patients were randomized. H. pylori eradication rates (intention-to-treat, n=173/per protocol, n=167) were 88%/91% for 7-day rabeprazole-based therapy, 72%/72% for 3-day rabeprazole-based therapy and 82%/89% for 7-day omeprazole-based therapy, respectively. The per protocol eradication rate was significantly better in the 7-day rabeprazole-based therapy and 7-day omeprazole-based therapy groups when compared to the 3-day rabeprazole-based therapy group (P=0.01 and P=0.04, respectively). Compliance was excellent and all three regimens were well tolerated. CONCLUSIONS: The efficacy of seven-day rabeprazole-based triple therapy is similar to 7-day omeprazole-based triple therapy for the eradication of H. pylori infection. 相似文献
949.
舌诊客化研究的一种图像处理方法 总被引:30,自引:0,他引:30
本文应用计算机图像识别研究中医舌诊的客观化,把舌像划分成36*36的舌像特征块(TTB)以分析局部纹理特征,提出了对每个小块分析彩色与纹理特征的两种算法,用CIEL*u*v*彩色空间模式的分层K-means聚类方法确定色彩类,用Gabor滤波器彩色对比特征与线性判断函数分析舌像纹理特征。文中的试验表明,这些方法在判断舌像时有较强的分辨力。 相似文献
950.