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81.
An international panel reviewed the methodology for clinical trials of spinal cord injury (SCI), and provided recommendations for the valid conduct of future trials. This is the second of four papers. It examines clinical trial end points that have been used previously, reviews alternative outcome tools and identifies unmet needs for demonstrating the efficacy of an experimental intervention after SCI. The panel focused on outcome measures that are relevant to clinical trials of experimental cell-based and pharmaceutical drug treatments. Outcome measures are of three main classes: (1) those that provide an anatomical or neurological assessment for the connectivity of the spinal cord, (2) those that categorize a subject's functional ability to engage in activities of daily living, and (3) those that measure an individual's quality of life (QoL). The American Spinal Injury Association impairment scale forms the standard basis for measuring neurologic outcomes. Various electrophysiological measures and imaging tools are in development, which may provide more precise information on functional changes following treatment and/or the therapeutic action of experimental agents. When compared to appropriate controls, an improved functional outcome, in response to an experimental treatment, is the necessary goal of a clinical trial program. Several new functional outcome tools are being developed for measuring an individual's ability to engage in activities of daily living. Such clinical end points will need to be incorporated into Phase 2 and Phase 3 trials. QoL measures often do not correlate tightly with the above outcome tools, but may need to form part of Phase 3 trial measures.  相似文献   
82.
MRI of pancreatic neuroendocrine tumours.   总被引:6,自引:0,他引:6  
Neuroendocrine tumours of the pancreas are rare and are frequently difficult to demonstrate. Several imaging modalities have been used to demonstrate these tumours, but recent reports have suggested that MRI may have an important role in their localization. We review the spectrum of MRI appearances of pancreatic neuroendocrine tumours.  相似文献   
83.
Study Type – Therapy (case series)
Level of Evidence 4

OBJECTIVE

To evaluate our experience with urethral recurrences in patients treated by radical cystectomy(RC) and orthotopic neobladder urinary diversion for carcinoma of the bladder.

PATIENTS AND METHODS

We retrospectively reviewed the records of patients treated with RC and orthotopic urinary diversion between January 1980 and July 2004.

RESULTS

In all, 260 patients underwent RC with a Studer or Hautmann orthotopic urinary diversion; the median (range) follow‐up was 5.1 (0–15.6) years. Six patients (2.3%) developed local recurrence of urothelial cancer (UC) within the urethra after this treatment. The median (range) time to presentation with recurrence after RC was 2.4 (0.7–3.6) years for pT1‐4 UC. Recurrences were treated with various methods, including transurethral resection, urethrectomy with conversion of neobladder to continent catheterizable diversion, and chemotherapy. At the last follow‐up, four of these six patients were alive without disease, one was alive with disease, and one had died from disease.

CONCLUSIONS

In our experience, local recurrences involving the urethra are infrequent. Complete surgical excision can provide a good outcome. Neoadjuvant chemotherapy should be considered for recurrences with adverse clinicopathological features.  相似文献   
84.
PURPOSE: Patients with locally advanced bladder cancer or who are not medically fit for surgery are a therapeutic dilemma. Radiotherapy with or without single agent cisplatin has been the major therapeutic modality. A phase II Southwest Oncology Group trial investigated the efficacy and feasibility of 5-fluorouracil, cisplatin and radiation in this patient subset. MATERIALS AND METHODS: Eligible patients had muscle invasive bladder cancer (clinical stages T2-T4) with nodal involvement at or below the level of bifurcation of the iliac vessels, were medically or surgically inoperable, or refused cystectomy. Patients underwent pretreatment cystoscopy and detailed tumor mapping, and were treated with 75 mg. /m.2 cisplatin on day 1 and 1 gm./m.2 daily, 5-fluorouracil on days 1 to 4 and definitive radiotherapy. Chemotherapy was repeated every 28 days, twice during and twice after radiation. RESULTS: From October 1993 to April 1998, 60 patients were enrolled in study. Of the 56 eligible patients 34% had unresectable tumors, 21% were not medically fit for surgery and 45% refused cystectomy. Overall, 68% of the patients had clinical T3 tumors or greater and 22% had nodal metastasis. Treatment was completed as planned in 32 of 56 (57%) patients. The most frequent grade 3 or 4 toxicities were neutropenia, stomatitis or mucositis, diarrhea, neuropathy and nausea. There were 53 patients who were evaluable for response, although response was not determined for 18. The overall response rate was 51% (95% confidence interval [CI] 37 to 65) based on intent to treat with a complete response rate of 49% (95% CI 35 to 63). Estimated median survival of the 56 patients was 27 months (95% CI 21 to 40 months) with an overall 5-year survival of 32%. The 5-year survival of the 25 patients who refused surgery was 45%. CONCLUSIONS: Concurrent 5-fluorouracil, cisplatin and radiation therapy is feasible. Despite a promising complete response rate, the overall 5-year survival suggests the need for more effective systemic therapy. The 5-year survival of patients who refused cystectomy suggests that this combined modality may provide another alternative to cystectomy for these patients.  相似文献   
85.
BACKGROUND: It is well documented that malnourished and/or obese surgical patients have increased morbidity and mortality post-operatively. Only a few studies investigating the effect of nutritional status on mortality are available pertaining to the transplant population. Since limited data are available on the nutritional status and its effects on mortality in the lung transplant population, we sought to ascertain whether there is an association between mortality and preoperative nutritional status. METHODS: We examined mortality during the first 3 months after transplantation. Patients were grouped by body mass index (BMI) categories as < 17 kg/m(2), 17 to < 20 kg/m(2), 20 to 25 kg/m(2) (reference group), > 25 to 27 kg/m(2), and > 27 kg/m(2). Additional risk factors retrieved from the pre-transplant records included age, gender, diagnosis, energy requirements, protein requirements, protein and caloric intake, and weight history. Logistic regression for univariate and multivariate analysis for mortality used recipient age, gender, disease category, pre-transplant cytomegalovirus (CMV) serology, transplant type (single or bilateral), and donor age, gender, and CMV serology. RESULTS: The likelihood estimates or odds ratios (ORs) of the risk of death within 90 days of lung transplantation for the BMI categories compared to the reference group were 3.7 for BMI < 17 kg/m(2) (p = 0.085), 1.6 for BMI < 17 to 20 kg/m(2) (p = 0.455), 3.5 for BMI > 25 to 27 kg/m(2) (p = 0.069), and 5.0 for BMI > 27 kg/m(2) (p = 0.003). CONCLUSIONS: In patients with a pre-transplant BMI < 17 kg/m(2) or > 25 kg/m(2) the risk of dying within 90 days post-transplant was increased. In patients with a pre-transplant BMI of > 27 kg/m(2) the risk was significantly higher in than the reference group.  相似文献   
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89.
Hospital-based medical residencies are slowly changing to include experience in ambulatory practices. This development is traced by the case example of the medical residency at the Massachusetts General Hospital which has always contained a component of ambulatory training. The history reveals that the institution's economy and work have determined the content and sequence of residency training, perhaps more than educational ideas on the proper training of the doctor. The early ambulatory experience (1900–1940) was prompted by the need to take care of a large number of outpatients, supported by the view of training for future private practice in the office. The residency became hospital-based (1940–1972) with the expansion of hospital beds, hospital insurance and of specialized jobs in academic medical centers. Residents were now required to care for more hospital patients, to manage the technology of acute care and to aid the growth of subspecialization. Although public interests today demand more ambulatory care, the future of expanded ambulatory training remains problematic, although a modern necessity if medicine is to redirect its attention to prevention and care outside the hospital. Expanded training outside the hospital depends on better financing of ambulatory services, the modernization of outpatient departments as group practices providing primary care, the development of teaching units and research in ambulatory practices, along with support for the idea of the generalist, which itself has had limited support by treatment and learning institutions.  相似文献   
90.
A pair of monozygotic twins discordant for systemic lupus erythematosus(SLE) were studied and no differences noted in their immune respose to tetanus toxoid, keyhole lympet hemocyanin, DNCB, delayed sensitivity, or antibody titers to viruses. Both were noted to have biologically false positive serology at an early age, but only one twon developed SLE. The clinically unaffected twin underwent castration at an early age, suggesting that ovarian hormones may play an important role in the development of SLE.  相似文献   
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