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61.
Despite decreasing mortality rates, morbidity is still high after pancreatic head resection. Comparative data in the United States and Europe show a relationship between hospital volume and mortality. Treatment strategies vary frequently, partially because of the lack of evidence-based data. We performed a multi-institutional analysis in Germany evaluating current numbers, indications, techniques, and complication rates of pancreatic head resection. Questionnaires were completed by seven high-volume surgical departments regarding quantitative and qualitative aspects of pancreatic head resections in the period from 1999 to 2004 (five prospective and two retrospective institutional databases). A total of 1454 pancreatic head resections (944 for malignancy) were reported. Mean annual hospital volume ranged from 14 to 52 (10 to 43 in malignancy). Mortality was between 1.1% and 4.8%, morbidity was between 24% and 46%, and pancreatic leakage was between 9% and 20%. In malignant disease, all centers perform standard lymphadenectomy and regard arterial infiltration as a contraindication for resection. However, the rate of portal vein resection varied from 0% to 28%. No consensus is seen on the type of surgery for malignancy and chronic pancreatitis. After resection for pancreatic cancer less than one fourth of the patients receive adjuvant therapy. The results of our analysis in Germany confirm that pancreatic head resection can be performed with low mortality in specialized units. Variations in indications, operative technique, and perioperative care may demonstrate the lack of evidence-based data and/or personal and institutional experience. The low number of patients receiving adjuvant therapy after resection of pancreatic cancer suggests that more efforts must be made to establish novel adjuvant therapies under randomized study conditions. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation).  相似文献   
62.
We thank Dr Villata et al. for their thought-provoking comments.Their concern about the suitableness to choose combined endpointsin clinical trials deserves some comment.  相似文献   
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Bronchiolitis obliterans syndrome (BOS) is the limiting factor to long-term survival after lung transplantation. Previous studies suggested respiratory viral tract infections are associated with the development of BOS. To identify the impact of virus detection in bronchoalveolar lavage (BAL) fluid, we analyzed BAL samples from 87 consecutive lung transplant recipients for human herpesvirus (HHV)-6, Epstein-Barr virus, Herpes simplex virus 1/2, Cytomegalovirus, respiratory syncytical virus and adenovirus by PCR. Acute rejection, BOS and death were recorded for a mean follow-up time of 3.27 +/- 0.47 years. Results of PCR analysis and other potential risk factors were entered into a Cox regression analysis of BOS predictors and death. Only acute rejection was a distinct risk factor for BOS of all stages, death and death from BOS. HHV-6 was detected in 20 patients. Univariate and multivariate analysis revealed that HHV-6 was associated with an increased risk to develop BOS > orb = stage 1 and death, separate from the risk attributable to acute rejection. Identification of HHV-6 DNA in BAL fluid is a potential risk factor for BOS. Our results warrant further studies to elucidate a possible causal link between HHV-6 and BOS.  相似文献   
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Concepts for stroke units that cover the acute phase vary. Therefore, the network of acute stroke units that is being set up in Austria in a uniform way is of general interest. This nationwide network has been established in accordance to evidence-based recommendations and prespecified criteria for available resources. The location for such a unit follows a maximum of 90-min isochrones (transport time) to the hospital. The quality of the network is currently documented and the results are reported. A nationwide stroke registry was prospectively performed on 15 stroke units that were already functional in this network. The aim was to document the quality performance of Austrian stroke units, focusing on rapid admissions, ready availability of investigations and therapies performed. Outcome measures were Barthel scale, Rankin score and percentages of complications. Between August 1998 and December 2000, 2,313 patients with ischemic stroke or with primary intracerebral hemorrhage admitted to an Austrian stroke unit within 24 h after onset of symptoms were prospectively included. Forty-three percent of the patients had a moderate or severe stroke. Fifty-seven percent of all patients were admitted to the stroke unit within 3 h after the onset of symptoms. Twenty-seven percent of these patients were brought in by ambulance accompanied by an emergency physician. Two percent of patients were admitted by helicopter. Fifty-four percent of patients had their first brain imaging within 30 min after admission, another 26% within 3 h. Intravenous thrombolysis was performed in 4.1% of patients. The overall stroke-unit mortality was about 6.8% and mortality at 3 months was 12.9%. The outcome at 3 months showed a modified Rankin Scale score of 0 or 1 in 47% of patients, denoting none or mild impairment. This network of acute stroke units is highly efficient in terms of rapid admissions, short intrahospital delays, as well as rapid use of readily available investigations. Stroke units seem to be well accepted by the general public and the medical community because our data show that all types of strokes are treated in Austrian stroke units, including severe strokes. The total number of concurrently treated acute strokes in other institutions across Austria is not known and no formal comparison with other systems of hospitalized care was undertaken, therefore further research is necessary.  相似文献   
69.
研究地西泮、苯巴比妥、普萘洛尔和西咪替丁对地西泮氧化代谢的影响及其药酶蛋白的初步分析,应用HPLC,SDS聚丙烯酰胺凝胶电泳和薄层扫描测定地西泮及其代谢物,并对大鼠肝微粒体和酶蛋白进行分离和含量测定。结果表明地西泮、普萘洛尔和西咪替丁使肝微粒体中P450含量明显降低。地西泮和普萘洛尔明显抑制地西泮C3羟化活性,大剂量普萘洛尔尚能抑制地西泮N脱甲基。苯巴比妥明显诱导P450生成,增强地西泮N脱甲基和C3羟化酶活性及分子量为51,000和59,000的电泳蛋白带,而地西泮、普萘洛尔则呈抑制作用。并发现,地西泮N脱甲基酶活性和分子量为59,000蛋白含量呈线性相关(P<0.05),而C3羟化酶活性则与51,000蛋白含量呈线性相关(P<0.01)。因此地西泮C3羟化代谢可能与51,000的P450酶蛋白有关,而N脱甲基代谢则可能与59,000的P450酶蛋白有关。  相似文献   
70.
Chlamydia trachomatis, the causative agent of trachoma, affecting hundreds of millions of people, is now recognized as a major cause of sexually transmitted disease. In many countries chlamydial infection now outstrips gonorrhoea as the major cause of genital tract infection. Chlamydial urethritis and cervicitis are frequently complicated by ascending infection involving the endometrium, the fallopian tubes and epididymis. This often results in serious reproductive sequelae, e.g., infertility in the female and ectopic pregnancy. Extra-genital manifestations of chlamydial infection may occur involving the eyes (follicular conjunctivitis), joints (arthritis), and distal intestinal tract. Infection of the newborn child during birth may result in ocular or lung disease.  相似文献   
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