首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   114篇
  免费   8篇
  国内免费   2篇
基础医学   12篇
临床医学   10篇
内科学   39篇
神经病学   1篇
特种医学   1篇
外科学   34篇
预防医学   3篇
药学   8篇
肿瘤学   16篇
  2021年   2篇
  2020年   1篇
  2019年   2篇
  2018年   2篇
  2016年   1篇
  2015年   1篇
  2014年   3篇
  2013年   1篇
  2012年   4篇
  2011年   8篇
  2010年   6篇
  2009年   3篇
  2008年   9篇
  2007年   4篇
  2006年   7篇
  2005年   8篇
  2004年   6篇
  2002年   4篇
  2001年   4篇
  2000年   4篇
  1999年   5篇
  1998年   4篇
  1996年   1篇
  1994年   2篇
  1992年   1篇
  1991年   1篇
  1990年   2篇
  1989年   2篇
  1988年   1篇
  1987年   3篇
  1986年   1篇
  1985年   2篇
  1984年   2篇
  1980年   1篇
  1979年   1篇
  1977年   2篇
  1976年   4篇
  1974年   1篇
  1973年   3篇
  1971年   1篇
  1967年   2篇
  1966年   2篇
排序方式: 共有124条查询结果,搜索用时 15 毫秒
1.
Patients with ulcerative colitis (UC) and Crohn's disease have an increased risk for developing cancer of the colon. Mutations in the K-ras gene are relatively frequent in specimens from patients with sporadic colon cancer, but less frequent in cases of cancer complicating ulcerative colitis. In order to study the problem further we used the polymerase chain reaction (PCR) technique followed by a restriction fragment length polymorphism (RFLP) assay, to detect mutations at codon 12 of K-ras in biopsy specimens from patients with UC or Crohn's disease. Six among 27 patients (22.2%) with UC and 2 of the 19 patients (10.5%) with Crohn's disease examined, carried a mutation at codon 12 of K-ras. Our results indicate that mutations in K-ras may be a genetic marker that would reveal the predisposition to colon cancer among this group of patients.  相似文献   
2.
Patients with inflammatory bowel disease (IBD)frequently suffer from thromboembolic events.Anti-cardiolipin (aCL) antibodies have been shown to beassociated with thrombosis. Recently, the antibodies against the anti-cardiolipin cofactor2-glycoprotein I(a2GPI) have been found with higherspecificity for thrombosis. The presence of theseantibodies was assessed in 128 patients with IBD [83 with ulcerative colitis (UC) and 45 withCrohn's disease (CD)] and 100 healthy controls (blooddonors). Patients with UC and CD had a significantlyhigher prevalence of aCL (18.1% and 15.6%, respectively) than healthy controls (HC) (3%). Eleven IBDpatients (8.6%) but no HC had a2GPI.None of the IBD patients with a history of thrombosishad aCL and only one of them (a UC patient with deepvein thrombosis of the right leg) had a high titer of IgGa2GPI. In conclusion, these data showthat both aCL and a2GPI aresignificantly associated with IBD but further studiesare needed to determine the significance of our findings.  相似文献   
3.
Acute complicated diverticulitis, particularly with colon perforation, is a rare but serious condition in transplant recipients with high morbidity and mortality. Neither acute diverticulitis nor colon perforation has been reported in young heart-lung grafted patients. A case of subclinical peritonitis due to perforated acute sigmoid diverticulitis 14 years after heart-lung transplantation is reported. A 26-year-old woman, who received heart-lung transplantation 14 years ago, presented with vague abdominal pain. Physical examination was normal. Blood tests revealed leukocytosis. Abdominal X-ray showed air-fluid levels while CT demonstrated peritonitis due to perforated sigmoid diverticulitis. Sigmoidectomy and end-colostomy (Hartmann's procedure) were performed. Histopathology confirmed perforated acute sigmoid diverticulitis. The patient was discharged on the 8th postoperative day after an uneventful postoperative course. This is the first report of acute diverticulitis resulting in colon perforation in a young heart-lung transplanted patient. Clinical presentation, even in peritonitis, may be atypical due to the masking effects of immunosuppression. A high index of suspicion, urgent aggressive diagnostic investigation of even vague abdominal symptoms, adjustment of immunosuppression, broad-spectrum antibiotics, and immediate surgical treatment are critical. Moreover, strategies to reduce the risk of this complication should be implemented. Pretransplantation colon screening, prophylactic pretransplantation sigmoid resection in patients with diverticulosis, and elective surgical intervention in patients with nonoperatively treated acute diverticulitis after transplantation deserve consideration and further studies.  相似文献   
4.
Tailgut cysts are developmental hamartomas found in the presacral space. They are usually detected incidentally during physical examinations or imaging studies. However, they may cause symptoms due to compression of nearby organs. Due to their potential malignant transformation, surgical resection is warranted, while routine biopsy is considered controversial because of the concern about infection of the tailgut cyst and needle-track implantation of malignant cells. The co-existence of a carcinoid in a tailgut cyst is extremely rare. Only 16 cases have been reported previously, the vast majority of which were found in females. We herein present the case of a carcinoid in a tailgut cyst found in a male patient, discuss the potential pathogenesis of tailgut carcinoids, and underline the fact that their previous consideration of the condition as a female-restricted entity should be rejected.  相似文献   
5.
Human immunodeficiency virus type 1 infects human helper T lymphocytes by an interaction between gp120, the viral coat protein, and the T-cell receptor CD4. Two microtiter-based immunoassays, an enzyme-linked immunosorbent assay (ELISA) and a particle concentration fluorescence assay, were developed to measure gp120-CD4 binding and were then used to screen a variety of compounds for the inhibition of this interaction. Additional protocols, called "consumption assays," were defined to distinguish inhibitors which functioned by sequestering either gp120 or CD4 to prevent the final effective bimolecular interaction. Monoclonal antibodies of defined specificity and compounds known from other published studies to inhibit gp120-CD4 binding were tested in an attempt to validate the assays used in the study. Once the capacity of these assays to detect known gp120-CD4 inhibitors was confirmed, they were used to screen synthetic agents and fermentation broths for novel compounds that might be used as human immunodeficiency virus receptor antagonists. A 2,4-diaminoquinazoline, CP-101,816-1, was found to inhibit this interaction (50% inhibitory concentration in ELISA, 32.5 micrograms/ml) and to interact more strongly with CD4 than with gp120 in the consumption assays. The identification of a novel inhibitor, a 2,4-diaminoquinazoline, confirmed that such assays are useful for the detection of human immunodeficiency virus type 1 receptor antagonists.  相似文献   
6.
Objective: To develop a clinical and prognostic scoring system predictive of survival after resection of intrahepatic cholangiocarcinomas (ICC). Patients: Two hundred and one consecutive ICC patients (83 from Essen, Germany, 54 from New York, USA and 64 from Chiba, Japan). The scoring systems were developed utilizing the data set from Essen University and then applied to the data sets from Mount Sinai Medical Center and Chiba University for validation. Eighteen potential prognostic factors were evaluated. Statistical analysis included multivariable regression analyses with the Cox proportional hazard model, power analysis, internal validation with structural equation modelling bootstrapping and external validation. The prognostic scoring model was based mainly in pathological and demographical variables, whereas the clinical scoring model was based mainly in radiological and demographical variables. Results: Gender (P=0.0086), UICC stage (P=0.0140) and R‐class (P=0.0016) were predictive of survival for the prognostic scoring model, while gender (P=0.0023), CA 19‐9 levels (P=0.0153) and macrovascular invasion (P=0.0067) were predictive of survival for the clinical scoring model. Prognostic points were assigned as follows: female:male=1:2 points, UICC (I–II):UICC (III–IV)=1:2 points and R0:R1=1:2 points. Clinical points were allocated as follows: female:male=1:2 points, CA 19‐9 (<100 U/ml):CA 19‐9 (≥100 U/ml)=1:2 points and no macrovascular invasion:macrovascular invasion=1:2 points. Prognostic groups with 3–4, 5 and 6 points (P=0.000001) and clinical groups with 3–4 and 5–6 points (P=0.0103) achieved statistically significant difference. Conclusions: We propose a clinical and prognostic scoring system predictive of long‐term survival after surgical resections for ICC.  相似文献   
7.
8.
Bleeding originating from the presacral venous plexus during pelvic operations is difficult to control, constituting a potentially life-threatening complication. Although suture ligatures, packing, and placement of tacks are established hemostatic techniques, they are often proved to be ineffective. We report a simple novel technique using spray diathermy for managing this severe complication. We have applied our method in four patients, two undergoing low anterior resection, and the others undergoing abdominoperineal resection for rectal cancer, that manifested severe presacral bleeding during rectal mobilization. Electrocautery at spray setting was applied slightly above the target bleeders at the presacral fascia, delivering a high-frequency electrical current in combination with drainage suction. In all cases, the method resulted in successful hemostasis. Applying spray electrocautery is a simple and effective method for controlling presacral bleeding. The advantages of using such a method instead of conventional hemostatic techniques include the option of varying the degree of haemostatic effect by altering the frequency and the volume of electric current.  相似文献   
9.
Hepatocellular carcinoma (HCC) generally develops as a consequence of underlying liver disease, most commonly viral hepatitis. The development of HCC follows an orderly progression from cirrhosis to dysplastic nodules to early cancer development, which can be reliably cured if discovered before the development of vascular invasion (typically occurring at a tumor diameter of approximately 2 cm). The identifiable population at risk makes screening a realistic possibility, and liver imaging is recommended every 6 months for patients with cirrhosis. For patients with preserved liver function and no portal hypertension who develop HCC that is confined to one region of the liver, resection is the preferred treatment. If resection is not possible because of poor liver function, and the HCC is within the Milan criteria (1 nodule > or =5 cm, 2-3 nodules > or =3 cm), liver transplantation is the treatment of choice. To prevent tumor progression while waiting, nonsurgical treatments including percutaneous ethanol injection, radiofrequency ablation, and transarterial chemoembolization are employed, but drop-out from the waiting list remains a problem. Living donor transplantation is an alternative that can eliminate drop-out and enable liver transplantation for patients with HCC whose disease does not fall within the Milan criteria. There is a need for more effective adjuvant therapies after resection and liver transplantation; newer antiangiogenic agents offer hope for improved outcomes in the future.  相似文献   
10.
The subject of anastomotic leakage after low anterior resection (LAR) for rectal cancer remains controversial. Risk factors have been discussed in several studies but the findings are often inconclusive. This review evaluates these studies and separates the known risk factors into those that are well documented, those that are obsolete, and those that require further research. We searched the Medline and PubMed databases using the keywords: “leakage,” “low anterior resection,” “rectal cancer,” “risk factors,” and their combinations. There were no language or publication year restrictions. References in published papers were also reviewed. Each risk factor was evaluated and discussed separately. The evidence suggests that low anastomoses are more prone to leakage. Other well-documented risk factors are male sex, smoking, and preoperative malnutrition. Routine mobilization of the splenic flexure and the use of a J-pouch seem to reduce the leakage rate. The effect of preoperative chemo-radiotherapy is under scrutiny. The indications for a protective stoma remain debatable. Omentoplasty, bowel preparation, the use of a drain, and tumor stage do not seem to affect the leakage rate. The type of operation (open or laparoscopic) and anastomosis (hand-sewn or stapled) is not crucial.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号