全文获取类型
收费全文 | 2213篇 |
免费 | 168篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 53篇 |
儿科学 | 108篇 |
妇产科学 | 19篇 |
基础医学 | 272篇 |
口腔科学 | 95篇 |
临床医学 | 168篇 |
内科学 | 429篇 |
皮肤病学 | 24篇 |
神经病学 | 109篇 |
特种医学 | 18篇 |
外科学 | 360篇 |
综合类 | 64篇 |
一般理论 | 1篇 |
预防医学 | 218篇 |
眼科学 | 141篇 |
药学 | 161篇 |
中国医学 | 8篇 |
肿瘤学 | 135篇 |
出版年
2023年 | 15篇 |
2022年 | 48篇 |
2021年 | 103篇 |
2020年 | 42篇 |
2019年 | 51篇 |
2018年 | 65篇 |
2017年 | 56篇 |
2016年 | 74篇 |
2015年 | 75篇 |
2014年 | 91篇 |
2013年 | 101篇 |
2012年 | 167篇 |
2011年 | 157篇 |
2010年 | 94篇 |
2009年 | 91篇 |
2008年 | 137篇 |
2007年 | 121篇 |
2006年 | 125篇 |
2005年 | 94篇 |
2004年 | 85篇 |
2003年 | 68篇 |
2002年 | 69篇 |
2001年 | 52篇 |
2000年 | 35篇 |
1999年 | 44篇 |
1998年 | 23篇 |
1997年 | 13篇 |
1996年 | 16篇 |
1995年 | 15篇 |
1994年 | 11篇 |
1992年 | 13篇 |
1991年 | 17篇 |
1990年 | 29篇 |
1989年 | 19篇 |
1988年 | 13篇 |
1987年 | 10篇 |
1986年 | 17篇 |
1985年 | 12篇 |
1983年 | 9篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1979年 | 13篇 |
1978年 | 8篇 |
1977年 | 4篇 |
1976年 | 8篇 |
1975年 | 5篇 |
1973年 | 7篇 |
1972年 | 6篇 |
1966年 | 4篇 |
1961年 | 8篇 |
排序方式: 共有2383条查询结果,搜索用时 15 毫秒
21.
Sabrina Anne Gonzalez Sivakumar Sivalingam 《Indian Journal of Thoracic and Cardiovascular Surgery》2021,37(3):329
Anomalous coronary arteries occur in as many as 12% of patients with tetralogy of Fallot (TOF). In patients with this condition, pulmonary hypoplasia can be prohibitive in performing a valve-sparing repair, subsequently resulting in various techniques to preserve the anomalous coronary artery. The management strategy is often complex in such a situation. We report on a case of TOF with an anomalous right coronary artery crossing the right ventricular outflow tract, with an unusual course of the right ventricular (RV) branch, which precluded placement of a valved conduit. In this case, we performed a successful repair with mobilization of the anomalous coronary artery and reconstruction of the right ventricular outflow tract with a limited transannular patch. 相似文献
22.
Metabolism and elimination of rhodamine 123 in the rat 总被引:1,自引:0,他引:1
Trevor W. Sweatman Ramakrishnan Seshadri Mervyn Israel 《Cancer chemotherapy and pharmacology》1990,27(3):205-210
Summary Little is known of the pharmacology of rhodamine 123 (RH-123), an agent reported to have carcinoma-selective experimental antitumor activity. Accordingly, using a high-performance liquid chromatographic assay system with fluorescence detection, we examined the plasma decay and the biliary and urinary elimination of parent drug and metabolites in female Sprague-Dawley rats receiving RH-123 at an intravenous dose (5 mg/kg) equivalent to the therapeutic dose used in murine tumor models. Following drug administration to unconscious animals, plasma levels of drug-associated fluorescence fell in a triphasic manner (t1/2, 15 min; t1/2, 1 h; t1/2, 4.7 h). In plasma, unchanged drug predominated but lower levels of the deacylated metabolite rhodamine 110 (RH-110) and two unknowns were also detectable throughout the study. Drug fluorescence was recovered extensively in both urine and bile. In unconscious animals with ureteral cannulae, urinary excretion (11.4% of the dose in 6 h) occurred predominantly as unchanged RH-123 (97% of the total), with low levels of RH-110 (2.4%) and two unknowns (<0.6% combined) also being present. Similarly dosed conscious animals (without surgical intervention) housed in metabolic cages showed a comparable pattern of urinary excretion, with 11.9% of the drug dose being recovered in 6 h and 21.9%, by 48 h. Biliary drug elimination accounted for 8% of the delivered dose in 6 h in unconscious animals and for 11% by 36 h in conscious animals fitted with biliary cannulae. In contrast to urinary excretion, in which unchanged drug predominated, only 50% of the fluorescence recovered in bile was attributable to RH-123. The remainder was due to a number of products that were detectable throughout the study. Of these, one present at significant levels was identified as a glucuronide conjugate of RH-123, based on the liberation of parent drug when the purified metabolite was incubated with -glucuronidase or hydrolyzed with 1 N hydrochloric acid. Further studies with a radiolabeled form of RH-123 are necessary to establish the identity of the remaining unknowns disclosed in this work.This work was supported in part by research grants CA 44890 (T.W.S.) and CA 37082 (M.I.) from the National Cancer Institute, National Institutes of Health, United States Public Health Service 相似文献
23.
GnRH agonists have been found to be clinically useful in several hormone-sensitive conditions, including cancer. However, there is controversy regarding a direct action of these agents on the pathologic tissue of a given disease process, in particular, tumors. In this study, we examined the effects of D-Trp(6) -LHRH, a potent GnRH agonist, on the expression of an increasingly important angiogenesis factor, VPF (vascular permeability factor)/VEGF (vascular endothelial growth factor). Ovarian carcinoma cell lines exposed to D-Trp(6) -LHRH in culture demonstrated a reversible inhibition of VPF mRNA expression and a parallel decrease in the endothelium-specific mitogenic activity of the conditioned media from these treated cultures. This study reports a novel activity of a GnRH agonist and provides a starting point to investigate the in vivo anti-angiogenic properties of GnRH peptide analogs. 相似文献
24.
25.
26.
Vascular endothelial growth factor (VEGF)/ vascular permeability factor (VPF) is emerging as an important growth factor in a variety of tumor types. As a potent endothelial cell mitogen and vascular permeabilizing agent, VEGF/VPF has the unique functional capacity to mediate the component events of solid tumor neovascularization and ascites tumor growth. In the present series of investigations, our experimental hypothesis was that VEGF/VPF is a critical mediator of ovarian carcinoma-associated ascites formation and solid tumor growth. Athymic nude mice xenotransplanted with human ovarian carcinoma cell lines received either a preimmune rabbit serum or VEGF/VPF antiserum. Compared with the control group receiving the preimmune serum, the antiserum-treated animals displayed a 10- and 12-fold reduction in ascites accumulation and solid tumor growth, respectively. The administration of a neutralizing antiserum to VEGF/VPF conferred a modest survival advantage to animals harboring intraperitoneal tumors. These data demonstrate the significance of VEGF/VPF in the pathogenesis of ovarian carcinoma and suggest that interventions targeting this growth factor and/or its receptor may be of therapeutic value in the management of ovarian cancer. 相似文献
27.
Depleted uranium is now widely used in the armor of military vehicles as well as in kinetic-energy penetrators designed to defeat enemy armor. As a result, the potential that personnel will be wounded by depleted uranium fragments has increased. Because toxicities associated with depleted uranium fragments may ultimately require different treatment protocols than those used for traditional metal fragment injuries, a method to rapidly detect the presence of depleted uranium in surgically excised shrapnel fragments is required. By treating the shrapnel fragment with an extracting agent, such as nitric acid, for 5 minutes in an ultrasonic cleaner, sufficient metal is solubilized to allow for colorimetric detection using a pyridylazo dye. Although several metals are capable of being detected under these conditions, the reaction can be made specific for depleted uranium through the use of masking agents such as sodium citrate and ethylenediaminetetraacetic acid. This procedure allows for the rapid (< 15 minutes) extraction and detection of depleted uranium in metal shrapnel fragments. 相似文献
28.
Reconstruction of the high-risk chest wall with endoscopically assisted latissimus dorsi harvest and expander placement 总被引:2,自引:0,他引:2
Certain patients requesting breast reconstruction may be described as having a high-risk chest wall with regard to implant loss and well-documented high complication rates. Such patients have a combination of one or more of the following: previous chest wall radiotherapy, heavy smoking, and thin, tethered chest wall flaps. If autologous transfer is not appropriate for such patients then reconstruction may be difficult. In this specific patient group the assistance of endoscopy has been used to raise the latissimus dorsi muscle to cover an expander placed within an endoscopically created chest wall pocket. The first 12 consecutive cases using this technique are discussed, showing an expander loss rate of 8% for the primary implant placement. 相似文献
29.
Michael Friedman MD Darius Bliznikas MD Ramakrishnan Vidyasagar MBBS MS Roee Landsberg MD 《Operative Techniques in Otolaryngology》2004,15(1):23
Endoscopic frontal sinus surgery is still considered difficult, risky to perform, and likely to result in a high failure rate. We have previously reported on our technique of endoscopic frontal sinus surgery, stressing the importance of identification and preservation of natural outflow tract. Our study of frontal sinus anatomy shows that the mean frontal ostium anterior—posterior and transverse dimensions are 7.22 ± 2.78 mm and 8.92 ± 2.95 mm, respectively; therefore, dissection of obstructive structures in frontal recess leads to a wide opening of frontal sinus outflow. A key surgical landmark in our technique is the superior attachment of the uncinate process. This article provides an update of the surgical anatomy of the frontal recess region and our surgical technique, as well as a discussion of our approach to frontal sinus revision surgery. 相似文献
30.