全文获取类型
收费全文 | 14877篇 |
免费 | 1016篇 |
国内免费 | 48篇 |
专业分类
耳鼻咽喉 | 188篇 |
儿科学 | 409篇 |
妇产科学 | 396篇 |
基础医学 | 2535篇 |
口腔科学 | 228篇 |
临床医学 | 1529篇 |
内科学 | 2516篇 |
皮肤病学 | 323篇 |
神经病学 | 1743篇 |
特种医学 | 606篇 |
外国民族医学 | 1篇 |
外科学 | 1574篇 |
综合类 | 104篇 |
一般理论 | 10篇 |
预防医学 | 1191篇 |
眼科学 | 282篇 |
药学 | 1052篇 |
中国医学 | 44篇 |
肿瘤学 | 1210篇 |
出版年
2023年 | 76篇 |
2022年 | 101篇 |
2021年 | 270篇 |
2020年 | 218篇 |
2019年 | 301篇 |
2018年 | 302篇 |
2017年 | 237篇 |
2016年 | 354篇 |
2015年 | 370篇 |
2014年 | 497篇 |
2013年 | 636篇 |
2012年 | 992篇 |
2011年 | 983篇 |
2010年 | 613篇 |
2009年 | 568篇 |
2008年 | 907篇 |
2007年 | 903篇 |
2006年 | 871篇 |
2005年 | 820篇 |
2004年 | 802篇 |
2003年 | 825篇 |
2002年 | 772篇 |
2001年 | 154篇 |
2000年 | 140篇 |
1999年 | 186篇 |
1998年 | 213篇 |
1997年 | 163篇 |
1996年 | 119篇 |
1995年 | 120篇 |
1994年 | 114篇 |
1993年 | 115篇 |
1992年 | 104篇 |
1991年 | 86篇 |
1990年 | 98篇 |
1989年 | 83篇 |
1988年 | 78篇 |
1987年 | 62篇 |
1985年 | 76篇 |
1984年 | 58篇 |
1983年 | 60篇 |
1982年 | 63篇 |
1981年 | 62篇 |
1980年 | 43篇 |
1979年 | 61篇 |
1978年 | 54篇 |
1977年 | 48篇 |
1976年 | 51篇 |
1974年 | 43篇 |
1972年 | 49篇 |
1955年 | 45篇 |
排序方式: 共有10000条查询结果,搜索用时 984 毫秒
941.
Komenaka IK Bauer VP Schnabel FR Joseph KA Horowitz E Ditkoff BA El-Tamer MB 《Archives of surgery (Chicago, Ill. : 1960)》2004,139(2):175-178
HYPOTHESIS: Interpectoral nodes can be the initial site of recurrent breast cancer. DESIGN: Retrospective review. SETTING: Comprehensive breast center, located in a university-based tertiary care center. PATIENTS: All patients undergoing operations for breast cancer at our breast center from 1995 to 2002 were reviewed. MAIN OUTCOME MEASURES: Patients with interpectoral node recurrence as the initial site of recurrent breast cancer were identified. RESULTS: During the 8-year period, 4097 patients underwent surgical management for breast cancer. During this time, 4 patients (0.1%) had recurrence at the interpectoral nodes. Three of the 4 patients were node-negative at the original operation. All lesions were mammographically occult. Preoperative needle biopsy was effective in the confirmation of malignancy. All 4 underwent excision without complications. CONCLUSIONS: Recurrence at the interpectoral nodes can be the initial site of surgical failure. These nodes may represent the site of primary drainage in a percentage of patients. The sentinel node identification technique, therefore, should diminish the number of patients affected by recurrence at this site. In patients with a palpable mass in the infraclavicular location, however, a high index of suspicion should be maintained. Workup should include additional breast imaging and needle biopsy prior to operation. 相似文献
942.
Langer S Nolte D Koeller M Steinau HU Khandoga A Homann HH 《Annals of plastic surgery》2004,53(2):137-140
Increasing evidence underlines the substantial pathophysiological impact of platelets on the development of ischemia/reperfusion injury (I/R) in flaps. Methods for studying dynamic platelet mechanisms in flaps in vivo are not available. The aim of this study was to develop a model enabling quantitative analysis of platelet kinetics and platelet-endothelium cell interaction within the microcirculation of muscle flaps in vivo. Balb/c mice (n = 16) were anesthetized, and an epigastric muscle flap was prepared. Autologous platelets were separated from blood donor animals (n = 16) and labeled ex vivo by means of rhodamine-6-G. After I/R (90 minutes' clamping, 10 minutes' reperfusion), the platelets were administered intra-arterially (i.a.). Microhemodynamics and kinetics of platelets were investigated by intravital fluorescence microscopy. I/R of muscle flaps induced disturbances in microcirculation. The number of rolling platelets, as well as platelets adhering to the inner vessel wall of venules, was increased in the ischemia group. Using intravital fluorescence microscopy, platelet kinetics were analyzed directly in flap microcirculation in vivo for the first time. Since platelet/endothelial cell interaction is a key event in the pathophysiology after microsurgical procedures, this model will help to understand basic molecular mechanisms of platelet behavior during I/R. 相似文献
943.
Enhancement of the immune response to residual intrahepatic tumor tissue by laser-induced thermotherapy (LITT) compared to hepatic resection 总被引:4,自引:0,他引:4
Isbert C Ritz JP Roggan A Schuppan D Rühl M Buhr HJ Germer CT 《Lasers in surgery and medicine》2004,35(4):284-292
BACKGROUND AND OBJECTIVES: In contrast to hepatic resection, thermally destroyed autologous tumor cells remain in situ after laser-induced thermotherapy (LITT). The aim of the study was to evaluate the effect of LITT and hepatic resection on the immune response to residual intrahepatic tumor tissue and the growth of untreated liver metastases. STUDY DESIGN/MATERIALS AND METHODS: Two independent adenocarcinomas (CC531) were implanted into 60 WAG rats, one in the right (control tumor) and one in the left liver lobe (treated tumor). The left lobe tumor was treated either by LITT or partial hepatectomy. The control tumor was submitted to further investigation 24 hours, 96 hours, 7 days, and 10 days after treatment. RESULTS: Ten days after treatment, control tumor volumes were 296+/-46 mm_ after LITT and 1,181+/-192 mm_, 1,387+/-200 mm_ after hepatic resection and no treatment, respectively (P<0.001). Peritoneal tumor spread was detected in 4/20 cases after LITT and in 17/20 cases after hepatic resection. Expression of CD8, B7-2 (CD86), and to lesser extent MHCII, LFA1 (CD11a), and ICAM1 (CD54), was significantly enhanced at the invasion front of control tumors after LITT compared to hepatic resection. CONCLUSIONS: Our results suggest that LITT increases the immune response against untreated intrahepatic tumor tissue, which can lead to reduced tumor growth. 相似文献
944.
Viehweg P Rotter K Laniado M Lampe D Buchmann J Kölbl H Heywang-Köbrunner S 《European radiology》2004,14(3):402-408
A study was undertaken to assess the diagnostic accuracy of contrast-enhanced MR mammography (MRM) of the contralateral breast in patients treated by breast-conserving therapy previously. A total of 119 patients underwent 145 standardized dynamic MR studies (1 T, T1-weighted 3D FLASH, 0.2 mmol Gd-DTPA/kg body weight). We retrospectively evaluated the results of conventional methods and MRM. A total of 11 contralateral carcinomas were present (detection rate 9%). The interval between treatment of the first primary and identification of contralateral malignancy was 9–80 months (mean 33 months). The MRM allowed detection of four otherwise occult malignancies. One of 11 cancer was missed on MRM due to benign appearance of enhancement. Compared with conventional methods MRM improved sensitivity (91 vs 64%) and specificity (90 vs 84%), respectively. This study suggests that additional MRM of the contralateral breast increases the diagnostic accuracy not only by enhancing the detection of second cancers but also by reducing false-positive results. 相似文献
945.
Seasonality in human semen quality of smokers and non-smokers: effect of temperature 总被引:2,自引:0,他引:2
Aim: To analyse the possible effect of seasonal variation on semen parameters. Methods: The participants consisted of 1688 men attending the andrology laboratory between 1991 and 1997 for reduced fertility in the couple. Semen analysis was performed according to the WHO manual. The 84 individual months of the study period were each assigned to one of the three groups according to the average monthly outside temperature; Group A (temperature <4.4℃), Group B (4.4℃-13.3℃) and Group C (>13.3℃). Results: When comparing the different sperm parameters, the morphology was significantly better in Group C. However, when the smokers were analysed separately, this difference disappeared and significant seasonal variations were found in sperm density, total sperm count, motility and total motile sperm; they were deteriorated in the warmer season. In non-smokers, no such negative effect of increased temperature was observed. Conclusion: Sperm quality is influenced by seasonal factors. Increased environmental tempe 相似文献
946.
Lohrer H Arentz S 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2004,25(5):349-356
A case history of a 13-year-old female national top-level gymnast, suffering from calcaneocuboid joint instability, is presented. The procedure was done as an anatomic repair by capsular reefing, which was augmented using a local periosteal flap. Initially, the athlete twisted her ankle. Clinical investigation revealed no sign of a lateral ankle ligament injury, but following this initial examination, recurrent giving-way of the foot occurred. She additionally felt significant but diffuse pain on the lateral side of the foot during loading in training and competition. For 2 months she was unable to run and conservative treatment failed. Diagnosis of a calcaneocuboid instability was established 4 months after the initial lesion by clinical and x-ray stress examination of the calcaneocuboid joint. Open surgery was successfully performed. Early functional posttreatment was done and the patient returned to full high-level gymnastics ability 16 weeks after surgery. Two years later, a similar injury occurred to the opposite calcaneocuboid joint and the same operative procedure again led to full sports ability. 相似文献
947.
Lawrence VA Hazuda HP Cornell JE Pederson T Bradshaw PT Mulrow CD Page CP 《Journal of the American College of Surgeons》2004,199(5):762-772
BACKGROUND: Elders undergo approximately 40% of more than 1 million major abdominal operations annually. Yet evidence about recovery to preoperative levels of functional independence is limited. This study details course and predictors of functional recovery after elective major abdominal operations in the elderly. STUDY DESIGN: This was a prospective cohort of 372 consecutive patients, 60 years old or more, enrolled from surgeons in private practice and two university-affiliated hospitals, assessed preoperatively and postoperatively at 1, 3, and 6 weeks, 3 and 6 months, using self-report and performance-based measures (Activities of Daily Living [ADL], Instrumental Activities of Daily Living [IADL], Medical Outcomes Study Short Form-36 Physical Component and Mental Component Scales [PCS, MCS], Geriatric Depression Scale [GDS], Folstein Mini-Mental State Exam [MMSE], timed walk, functional reach, hand grip strength). RESULTS: Mean age was 69 +/- 6 years with 56% men, 47% nonHispanic Caucasian, and 42% Mexican American; hospital distribution was 49% private, 51% university-affiliated. Maximum functional declines (95% CI) occurred 1 week postoperatively: ADL, 2.8 points (2.4 to 3.2); IADL, 7.6 points (7 to 8.3); SF-36 PCS, 6.5 points (5.4 to 7.6); Mini-Mental State Exam, 0.5 points (0.2 to 0.7); timed walk, 6.8 seconds (5.2 to 8.4); functional reach, 1.7 inches (1.2 to 2.2); grip strength, 2 kilograms (1.3 to 2.7) (p < 0.001 for all). SF-36 mental component scale and Geriatric Depression Scale scores did not worsen. Mean recovery times were: Mini-Mental State Exam, 3 weeks; timed walk, 6 weeks; ADL, SF-36 PCS, and functional reach, 3 months; and IADL, 6 months. Mean grip strength did not return to preoperative status by 6 months. The incidence of persistent disability at 6 months, compared with preoperative status, was: ADL, 9%; IADL, 19%; PCS, 16%; mental component scale, 17%; timed walk, 39%; functional reach, 58%; and grip strength, 52%. Potentially modifiable independent predictors of ADL and IADL recovery were preoperative physical conditioning and depression plus serious postoperative complications. CONCLUSIONS: The clinical course of functional recovery varied across different measures. Protracted disability at 6 months after operation was substantial. Several potentially modifiable factors consistently predicted recovery. 相似文献
948.
The Tension Mounts: Mechanics Meets Morphogenesis and Malignancy 总被引:1,自引:0,他引:1
The tissue microenvironment regulates mammary gland development and tissue homeostasis through soluble, insoluble and cellular cues that operate within the three dimensional architecture of the gland. Disruption of these critical cues and loss of tissue architecture characterize breast tumors. The developing and lactating mammary gland are also subject to a plethora of tensional forces that shape the morphology of the gland and orchestrate its functionally differentiated state. Moreover, malignant transformation of the breast is associated with dramatic changes in gland tension that include elevated compression forces, high tensional resistance stresses and increased extracellular matrix stiffness. Chronically increased mammary gland tension may influence tumor growth, perturb tissue morphogenesis, facilitate tumor invasion, and alter tumor survival and treatment responsiveness. Because mammary tissue differentiation is compromised by high mechanical force and transformed cells exhibit altered mechanoresponsiveness, malignant transformation of the breast may be functionally linked to perturbed tensional-homeostasis. Accordingly, it will be important to define the role of tensional force in mammary gland development and tumorigenesis. Additionally, it will be critical to identify the key molecular elements regulating tensional-homeostasis of the mammary gland and thereafter to characterize their associated mechanotransduction pathways. 相似文献
949.
Hassmanová V 《Acta medica (Hradec Králové). Supplementum Universitas Carolina, Facultas Medica Hradec Králové》2004,47(2):107-120
The paper summarizes the principal information on the properties and effects of asbestos and a survey of diseases which can be recognized in the Czech Republic as occupational diseases according to the List of Occupational Diseases (Government Order 290/1995 Coll.). The paper lists possible diagnostic means and criteria for evaluation and presents a survey of developmental trends of the disease in exposed workers of the plant under study. In the period of years 1951-2003, 87 cases of occupational diseases were reported. The first asbestosis occurred in 1955, the first lung cancer in a patient with a previously reported asbestosis in 1962, the first pleural mesothelioma in 1976, the first asbestosis of the lung with concurrent lung cancer in 1981, and the first pleural hyalinosis in 1999. A very serious fact is that 56, i.e. 64.4% of diseases, particularly lung cancer and mesothelioma, were diagnosed after the termination of working in risk and many years of latency. A long-term folow-up of workers, even of those with a short exposure, is therefore necessary. 相似文献
950.