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21.
Adenoid cystic carcinoma: factors influencing survival.   总被引:10,自引:0,他引:10  
We have reviewed our experience with 264 patients treated for adenoid cystic carcinoma of salivary origin. This study updates a previous report from our hospital and includes all patients treated during a 30 year period who were eligible for a minimum follow-up of 10 years. The tumor arose in minor salivary (mucous) glands in two thirds of the patients; half had received treatment elsewhere, and both sexes were equally represented. Actuarial survival curves and "cure" rates calculated by the direct method confirm that clinical staging provides a reliable prognostic guide. We are unable to demonstrate that the microscopic appearance of the tumor exerts a predictable effect on treatment results. Although some patients lived for many years after resection despite local recurrence and distant metastases, prolonged survival was unusual in patients with stage 3 lesions, particularly in those with sinus or submaxillary gland primaries. Based on the site of origin of the tumor and its clinical stage, it is now possible to select which patients with adenoid cystic carcinoma have the most ominous prognosis and perhaps plan a more appropriate operation. More importantly, these data may help focus on the subpopulation at greatest risk, which is vital to the design of any prospective study to assess the value of adjunctive irradiation and chemotherapy.  相似文献   
22.
The Task Force for Creating a Biomedical Communications System for Dermatology was commissioned by the American Academy of Dermatology to develop an experimental segment of a computerized data bank on dermatologic therapy. The Task Force has completed such a "first generation" system and has named it DermRx. Its data bank carries the following information on each entry: the name of the disease; topical, systemic, physical, and other kinds of treatment; caveats; references to the literature; and the date and reviewer(s). The DermLit and DermRx programs are two components of a projected broader concept of an eventual comprehensive Biomedical Communications System for Dermatology. Such a system is envisaged as a means of making available to dermatologists diverse data relevant to practice, teaching, research, and business aspects of the specialty. At the moment, access to the stored information on dermatologic literature and therapy is by telephone call to, or by correspondence with, the central computer facility at Northwestern University. Eventually it is projected to be accessible by dedicated microcomputers housed in the physician's office. This preliminary report on DermRx is presented to review the progress of the project to date and to elicit comment upon its structure and value.  相似文献   
23.
Vascular access through subcutaneous prosthetic arteriovenous fistulas was studied in eighteen dogs. Dacron velour and woven Dacron grafts (6 mm diameter) were constructed across the lower abdomen between the common femoral artery and the opposite common femoral vein. In heparinized animals 197 percutaneous punctures were made with a "14 guage hemodialysis cannula at weekly intervals. Over a period of one and a half years there was no instance of infection. One of the fourteen Dacron velous and all four woven Dacron fistulas thrombosed. These data suggested the feasibility of achieving repetitive blood access through Dacron velour vascular prostheses. Nineteen Dacron velour fistula bypasses between the brachial artery and median basilic vein were performed in fifteen selected patients for a total dialysis period of ninety-six months. Failed standard subcutaneous fistulas or absence of suitable vessels in the upper extremity were indications for the primary procedure. Of three looped forearm fistulas, two thrombosed at twenty-two and two months. Complications among sixteen straight bypasses in the arm included two graft infections and one cannula tract infection. There were no instances of thrombosis in this group. The advantages of single needle dialysis in these high risk patients have been emphasized. Eleven grafts are presently functioning two to nine months postoperatively. Our preliminary results suggest that a Dacron velour fistula merits consideration as an alternative for vascular access in maintenance hemodialysis.  相似文献   
24.
The Authors compare the results obtained between two groups of patients suffering from leg lipodystrophy, who were subjected to a reducing lipoplasty. In the first group, surgeons made use of a new sort of cannula, deprived of the classical grip, whereas in the second group, they employed the traditional probe. The best results, achieved with the first group, prove this new operating system is really effective, particularly on legs, for the following reasons: (1) Higher precision and better control of the instrument (2) Swan-neck cannula abolition (3) Opportunity to operate with both hands (4) Halved operating time (5) No tiredness after the operation.  相似文献   
25.
Beran RG  Beran ME 《Epilepsia》2000,41(7):875-879
PURPOSE: Trials of antiepileptic medications are usually based in tertiary referral centers with teaching hospital resources. Epilepsy Research & Services (ERS) is part of a private outpatient neurological clinic that is involved in research as part of multicenter clinical trials, adhering to Good Clinical Research Practice. ERS is subject to external monitoring and auditing, but does so outside of the teaching hospital environment. METHODS: The clinic is operated by a neurologist supported by a research assistant, administrative and nursing staff and has no formal university attachment. Patients are recruited for trials from routine referrals for clinical care. The center has formal ties with the ethics committee of the local teaching hospital, but none of the team is formally attached to that hospital. RESULTS: The center conducted trials of zonisamide, oxcarbazepine, gabapentin, remacemide, tiagabine, vigabatrin, felbamate, and lamotrigine both as add-on trials in refractory seizure disorders and as monotherapy trials in de novo epilepsy. More than 200 patients have been recruited for trials at ERS (with some patients being involved in more than one trial). External review endorsed ERS as a superior environment for such research and as a model for other centers. CONCLUSIONS: Private practice is a viable alternative for the conduct of clincial trials and should be considered when establishing such protocols. Simplicity of administration and clinical practice, which more closely mirrors standard patient care, may enhance recruitment and management.  相似文献   
26.
董津生 《职业与健康》2004,20(12):164-165
目的探讨术前新辅助化疗对乳腺癌的疗效及提高患者术后生存率的作用.方法采用CMF和CAF两种化疗方案对50例Ⅲ期乳腺癌术前患者(A组)进行化疗,评价其疗效;与术后化疗(B组)进行总疗效对照比较.结果术前新辅助化疗组经化疗肿瘤全消和部分消退合计总有效率为58.0%;术后随访5 a生存率、无瘤存活率明显高于对照B组,两组无瘤存活率比较χ2=9.07,P<0.01.结论术前全身治疗(化疗)作为乳腺癌第一步治疗可能是首先使已存在的临床小转移灶得以控制,进而获得更多治疗成功的机会.  相似文献   
27.
从病因病机(经络论证、脏腑论证)、治疗(汤剂、固定组方、针灸)论述中医治疗重症肌无力。认为,应规范临床科研优选最佳科研方案,建立统一的疗效评定标准。  相似文献   
28.
蒋高霞  徐桂华  孟娣娟  姜荣荣  李洁 《河南中医》2012,32(12):1610-1612
目的:探索肢体缺血预处理对肝脏缺血再灌注损伤的影响.方法:32只新西兰兔用四氯化碳颈背部皮下注射法建立肝硬变模型.将成功建模的28只肝硬变兔分为假手术组(S组)、缺血再灌注组(IR组)、肝脏缺血预处理组(IPC组)、肢体缺血预处理组(LIPC组)各7只.实验前12h禁食,自由饮水.检测模型试验前后肝脏生化酶(ALT、AST)指标及肝脏组织中ATP含量水平.结果:LIPC组ALT、AST指标与S组、IR组比较差异均有显著统计学意义(P<0.01),与IPC组比较无统计学意义(P>0.05);LIPC组ATP指标水平与S组、IR组比较差异均有显著统计学意义(P<0.01),与IPC组比较无统计学意义(P>0.05).结论:肢体缺血预处理对肝脏缺血再灌注损伤具有保护作用.  相似文献   
29.
目的:观察芎芍胶囊对心肌梗死大鼠缺血心肌血管新生的影响.方法:采用开胸结扎冠状动脉左前降支的方法建立心肌梗死模型,清洁级(或SPF级)SD大鼠(雌雄各半)分为模型组、高剂量组、中剂量组、低剂量组,每组8只,分别用生理盐水、芎芍胶囊高、中、低剂量进行灌胃给药,连续给药6周后采集血,分离样本,并按规定保存,用免疫组化评分法...  相似文献   
30.
Coronavirus disease 2019 (COVID-19) is associated with poor cardiovascular outcomes in patients with heart failure (HF) of all categories of ejection fraction (EF), but mainly in patients with HF with reduced EF. Moreover, cardiac transplant patients exhibit worse cardiovascular prognosis, high mortality, and more admissions to the intensive care unit. In general, COVID-19 seems to de-teriorate the clinical status of HF and favors the development of acute respiratory distress syndrome and multiorgan failure, especially in the presence of cardiovascular comorbidities such as diabetes mellitus, kidney dysfunction, and older age. COVID-19 may induce new-onset HF with complex mechanisms that involve myocardial injury. Indeed, myocardial injury comprises a large category of detrimental effects for the myocardium, such as myocardial infarction type 1 or type 2, Takotsubo cardiomyopathy, microvascular dysfunction and myocarditis, which are not easily distinguished by HF. The pathophysiologic mechanisms mainly involve direct myocardial damage by severe acute respiratory syndrome coronavirus 2, cytokine storm, hypercoagulation, inflammation, and endothelial dysfunction. The proper management of patients with COVID-19 involves careful patient evaluation and ongoing monitoring for complications such as HF.  相似文献   
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