全文获取类型
收费全文 | 2058篇 |
免费 | 149篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 173篇 |
妇产科学 | 30篇 |
基础医学 | 178篇 |
口腔科学 | 35篇 |
临床医学 | 153篇 |
内科学 | 488篇 |
皮肤病学 | 13篇 |
神经病学 | 168篇 |
特种医学 | 80篇 |
外科学 | 432篇 |
综合类 | 43篇 |
一般理论 | 1篇 |
预防医学 | 88篇 |
眼科学 | 40篇 |
药学 | 95篇 |
中国医学 | 4篇 |
肿瘤学 | 180篇 |
出版年
2024年 | 5篇 |
2023年 | 23篇 |
2022年 | 59篇 |
2021年 | 108篇 |
2020年 | 61篇 |
2019年 | 95篇 |
2018年 | 109篇 |
2017年 | 86篇 |
2016年 | 68篇 |
2015年 | 77篇 |
2014年 | 122篇 |
2013年 | 162篇 |
2012年 | 197篇 |
2011年 | 210篇 |
2010年 | 132篇 |
2009年 | 91篇 |
2008年 | 130篇 |
2007年 | 105篇 |
2006年 | 98篇 |
2005年 | 87篇 |
2004年 | 74篇 |
2003年 | 36篇 |
2002年 | 39篇 |
2001年 | 4篇 |
2000年 | 8篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 10篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1985年 | 2篇 |
排序方式: 共有2216条查询结果,搜索用时 15 毫秒
101.
Poullis AP Zar S Sundaram KK Moodie SJ Risley P Theodossi A Mendall MA 《European journal of gastroenterology & hepatology》2002,14(4):409-412
BACKGROUND: Patients presenting to gastroenterology clinics with symptoms suggestive of lower-bowel disorders often require extensive investigation to differentiate functional from organic disease. C-reactive protein (CRP) is a sensitive marker of systemic inflammation. Levels of CRP are frequently raised in cases of inflammatory bowel disease (IBD). However, using conventional assays, not all cases of IBD have a detectable level. OBJECTIVE: To determine whether a new highly sensitive CRP enzyme-linked immunosorbent assay (ELISA) can aid the differentiation between IBD and functional bowel disorders (FBDs) in gastroenterology outpatients presenting with lower-bowel symptoms. METHODS: Serum was taken from 224 subjects attending a gastroenterology outpatient clinic. Of these, 203 were new patients and 21 were follow-up patients with quiescent colitis. The serum was analysed using a sensitive in-house ELISA. All new patients had a rigid sigmoidoscopy and rectal biopsy. Patients were investigated as deemed appropriate by the attending physician. Notes were reviewed after at least 6 months to determine the final diagnosis. RESULTS: A cut-off value of 2.3 mg/l had a sensitivity of 100% and a specificity of 67% in differentiating FBD from new cases of IBD. The geometric mean CRP was 0.383 mg/l in the constipation-predominant FBD group, 1.435 mg/l in diarrhoea-predominant FBD, 1.455 mg/l in quiescent IBD, 8.892 mg/l in newly presenting cases of ulcerative colitis, and 13.123 mg/l in newly presenting cases of Crohn's disease. CONCLUSION: A new, highly sensitive assay for CRP may help to distinguish FBD from IBD. 相似文献
102.
Specificity of mammography and US in the evaluation of a palpable abnormality: retrospective review 总被引:8,自引:0,他引:8
Moy L Slanetz PJ Moore R Satija S Yeh ED McCarthy KA Hall D Staffa M Rafferty EA Halpern E Kopans DB 《Radiology》2002,225(1):176-181
PURPOSE: To determine the number of patients who received a diagnosis of breast cancer after having an area of clinical concern at presentation and combined negative mammographic and ultrasonographic (US) findings. MATERIALS AND METHODS: During a 4-year period, 829 patients with a palpable abnormality at presentation and combined negative mammographic and US findings were identified. The number of women who went on to receive a diagnosis of breast cancer was determined retrospectively. The authors searched the breast imaging database and the pathology database, sent a contact letter to the referring physicians, and linked their data to the State Cancer Registry. They also analyzed the breast parenchymal density among all patients who had more than 2 years of follow-up. RESULTS: Of the 829 women, 374 had follow-up information. Two-hundred thirty-three patients had negative imaging findings with more than 2 years of follow-up. The other 141 women were presumed to be cancer free, as they were not identified by the State Cancer Registry. Six (2.6%) of the 233 women had a diagnosis of breast cancer in the area of the palpable abnormality. The six cancers were diagnosed among the 156 women who had radiographically dense breast tissue (Breast Imaging Reporting and Data System category 3 or 4). Among the 77 women with predominantly fatty tissues, no cancers were diagnosed. CONCLUSION: A negative mammographic and US finding of a palpable abnormality does not exclude breast cancer, but the likelihood of breast cancer is low, approximately 2.6%-2.7%. It may be higher if the breast tissues are dense and lower if they are predominantly fatty. 相似文献
103.
Volume Contents
Volume Contents 相似文献104.
Ovarian cancer is the leading cause of death in women with gynecological malignancies and overall survival for patients with advanced epithelial ovarian cancer (EOC) remains poor. The majority of patients recur after initial treatment. A strategy for improving outcome is to minimise recurrence via targeted therapy in patients after front-line therapy, or more appropriately as consolidation therapy. EOC represents an attractive target because of the biology of the disease and that the bulk of disease occurs in the peritoneal cavity. To initiate targeted therapy, a candidate target must be identified. Innovative approaches via targeted therapy to control metastatic residual EOC are currently under investigation. The targets are molecules and pathways, on which cancer cells depend to proliferate, invade, metastasise and prevent apoptosis. Potential targeted therapies include: proapoptototic therapy, suicide gene therapy, signal transduction, antiangiogenesis, immunotherapy and cytokine therapy. The utilisation of these targets in the clinic demands carefully conducted, well-coordinated but discovery-oriented translational research in the form of clinical trials that can quickly assess alternative strategies or combination of strategies that could result in clinical benefit. Therefore, targeted therapy for epithelial ovarian cancer, especially after complete response to standard regimens, represents a paradigm whose time has come to be nurtured. 相似文献
105.
Extra articular arthroscopic release in post-traumatic stiff knees: a prospective study of endoscopic quadriceps and patellar release 总被引:2,自引:0,他引:2
Knee stiffness due to mismanaged trauma is still common in underdeveloped countries. Many patients with distal femoral fractures, patellar injuries or other local trauma present with intra-articular and extra-articular adhesions between the quadriceps and anterior femur. Nineteen knees with post trauma stiffness due to combined intra- and extra- articular aetiology were taken up for arthroscopic aided release after failing an aggressive physiotherapy protocol. Ultrasound was used to identify the extra-articular adhesions. The intra-articular part of the release was done by a standard protocol involving the release of all infrapatellar, suprapatellar and gutter adhesions, and then the extra-articular proximal adhesions were released by using special long periosteal elevators and arthroscopic scissors. We were able to release the adhesions as high as 9 inches above the patella, and in one case bony ankylosis between the patella and the femur was arthroscopically osteotomised (after 11 years of stiffness). Delay before surgery averaged 2.7 years (6 months-11.3 years). Mean active flexion at one year follow-up improved from 27.3 degrees to 119.3 degrees (average increase: 92 degrees). Mean preoperative extension lag reduced from 6 degrees to 1 degrees postoperatively. No CPM machine was available, and patients had to undergo daily manual and assisted therapy, with appropriate analgesia. Overall patient satisfaction was excellent; one patient developed a supracondylar fracture (infected old fracture with bone loss and severe contracture) and was retrospectively a wrong case selection. Arthroscopic aided quadriceps adhesion release is a good option in cases of neglected trauma; results are excellent even without sophisticated CPM machines, and the periosteal elevators needed are cheap and indigenous. 相似文献
106.
Pulmonary interstitial emphysema PIE is a recognized sequel of high pressure mechanical ventilation. Nevertheless, with the improvement in perinatal medical care, PIE started to be seen in spontaneously breathing infants. We present a 29-week-old girl who developed PIE on the first day of life, while she was on nasal continuous positive airway pressure, and was successfully managed with high frequency oscillatory ventilation. There is a paucity of these cases in the literature. We report on the occurrence of this entity, early reorganization, and the possible associated or causation factors. 相似文献
107.
Ouwenga MK Sharma SK Holley P Turk TM Perry KT 《Journal of endourology / Endourological Society》2005,19(7):894-897
PURPOSE: We compared the load-release points of the Stone Cone and the new Cook Urological NTrap devices using an in vitro model of the ureter. MATERIALS AND METHODS: A strictured-ureter model was created using urethane tubing with a wire tie around it. A plastic bead was lodged above this narrowing. The Stone Cone, then the NTrap, was deployed in turn above this bead. The force required for each device to undeploy was measured over five trials. RESULTS: Each device released the bead in every trial. The Stone Cone released at a mean of 0.190 lb, while the NTrap yielded at 0.861 lb. CONCLUSIONS: Both of the devices released the plastic bead reliably and at low loads, although the NTrap did require statistically significantly more force than the Stone Cone. However, the loads for both devices were <1 lb, so the devices are unlikely to result in ureteral trauma. Whether a slight increase in load-release force or differences in design result in better stone-clearing ability of one device should be assessed in clinical trials. 相似文献
108.
BACKGROUND AND PURPOSE: Urinary-tract fistulas present unique clinical challenges that often necessitate open surgical excision with interposition of healthy tissue. Advances in retrograde instrumentation have enabled endourologists to employ more minimally invasive approaches to urologic disease, including fistulas. We reviewed our experience with endoscopic injection of fibrin glue for the treatment of urinary-tract pathology. PATIENTS AND METHODS: We performed a retrospective review of the eight patients at our institution who have undergone retrograde endoscopic injection of fibrin glue for the treatment of urinary-tract pathology. The data collected included age, presentation, treatment technique, method/duration of follow-up, complications, and success, which was defined as subjective and objective resolution of the treated pathology. RESULTS: One of these patients was treated for a caliceal diverticulum refractory to percutaneous ablation. The other seven patients were treated for fistulas, including one colovesical fistula, two vesicovaginal fistulas, one ileal conduit-cutaneous fistula, one ureterocutaneous fistula, one urethrocutaneous fistula, and one ureterorectal fistula. All lesions except the urethrocutaneous fistula and the ureterorectal fistula were treated with a single injection of fibrin glue. At a mean follow-up of 11.75 months, this technique was successful in six cases (75%). Two (33%) of the successfully treated patients required two injections. There were no complications. Failures were apparent at initial follow-up. CONCLUSION: Retrograde endoscopic injection of fibrin glue offers a novel approach to ablation of caliceal diverticula. Additionally, although open surgical excision of urinary-tract fistulae remains the gold standard treatment, endoscopic injection of fibrin glue offers a safe, minimally invasive approach that may avoid the morbidity of open surgery in such challenging patients. 相似文献
109.
Pai RR Shaktawat SS Khadilkar UN Lobo FD Rao VS Philipose R 《Indian journal of pathology & microbiology》2005,48(3):370-372
Majority of the Sclerosing stromal tumours of the ovary documented in the literature are single case reports. We report a series of 4 cases. Among the 4 cases encountered the mean age at presentation was 22.2 years. The clinical presentation varied from asymptomatic mass per abdomen (2 cases), menorrhagia (1 case) and amenorrhoea (1 case). The tumour was unilateral in all the cases with an average size of 10 cms. Grossly the appearances varied from a solid, partly cystic, edematous tumour (2 cases) to solid,firm tumour with yellow flecks (1 case) to unilocular cystic tumour (1 case). Microscopically, the tumour was characterized by cellular pseudolobules composed of a disorderly admixture of collagen-producing fibroblasts and lipid rich lutein cells with shrunken nuclei. In one case the lutein cells had a robust appearance with abundant cytoplasm and vesicular nuclei. The pseudolobules were very vascular and separated by hypocellular dense to oedematous fibrous tissue. Frozen section demonstrated fat in luteinized cells in 3 cases. 相似文献
110.