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101.
PURPOSE: Patients with head and neck squamous cell carcinoma (HNSCC) often clinically present with metastases to regional lymph nodes. Fine-needle aspiration of neck masses is routinely used to establish the presence of metastatic carcinoma and in turn to initiate a subsequent workup to determine the site of tumor origin. Human papillomavirus (HPV) 16 is an important etiologic agent for HNSCCs that arise from the oropharynx but less so for tumors from non-oropharyngeal sites. HPV16 detection thus provides a strategy for localizing an important subset of HNSCCs, but this approach has not been applied to fine-needle aspiration specimens. EXPERIMENTAL DESIGN: We did in situ hybridization for HPV16 on 77 consecutive aspirated neck masses diagnosed as metastatic squamous cell carcinoma. P16 immunohistochemistry was also done because p16 overexpression may serve as a surrogate marker of HPV-associated HNSCC. RESULTS: HPV16 was detected in 13 of the 77 (17%) aspirates. By site of origin, HPV16 was detected in 10 of 19 metastases from the oropharynx but in none of 46 metastases from other sites (53% versus 0%; P < 0.0001). HPV16 was not detected in 2 branchial cleft cysts misdiagnosed as metastatic squamous cell carcinoma, but it was detected in 3 of 10 metastases from occult primary tumors. P16 expression was associated with the presence of HPV16: 12 of 13 HPV16-positive metastases exhibited p16 expression, whereas only 4 of 62 HPV16-negative metastases were p16 positive (92% versus 6%; P < 0.0001). P16 expression also correlated with site of tumor origin: 13 of 19 oropharyngeal metastases were p16 positive, whereas only 1 of 46 non-oropharyngeal metastases was p16 positive (68% versus 2%; P < 0.0001). CONCLUSIONS: HPV16 status can be determined in tumor cells aspirated from the necks of patients with metastatic HNSCC. Its presence is a reliable indicator of origin from the oropharynx.  相似文献   
102.
A total of 20 children (median age 11 years) were treated for primary thyroid carcinoma from 1976 to 1990. Papillary adenocarcinoma was diagnosed in 19 and follicular in one case. Nineteen of 20 patients were considered amenable to surgery, which consisted of total thyroidectomy in 14 and partial thyroidectomy in 5. Only one patient with extensive perithyroid soft tissue infiltration was treated with external beam radiotherapy. Monolateral or bilateral cervical nodal dissection was performed in eight and six children, respectively; in nine cases without clinical evidence of metastatic nodes. Pathological examination showed that tumor extent was greater than that clinically assessed: Multiple tumor foci within the thyroid were assessed in 8/19, unilateral positive nodes in 8, and bilateral in 6, and soft tissue infiltration in 7. Subsequently 10 patients received thyroid-stimulating hormone (TSH) suppressive hormonotherapy. Relapses occurred in 7/20 at 2–48 months (median 18) from primary treatment: Four in cervical nodes, two in cervical nodes and lungs, and one in lungs. These seven patients were salvaged with node dissection and radioiodine therapy for lung metastases. All the 20 children are alive and disease-free after a median follow-up of longer than 10 years. The incidence of relapse was greater in the group of patients not given TSH-suppressive hormonotherapy. Total thyroidectomy produced permanent hypoparathyroidism in 5/14 (36%). Thyroid carcinoma in children of this series frequently presented with multiple tumor foci within the thyroid and cervical node metastases. Prognosis was favourable even after relapse and was not related to the extent of surgical treatment. Limited surgery and suppressive hormonotherapy may be adequate therapy for thyroid carcinoma in children. © 1995 Wiley-Liss, Inc.  相似文献   
103.
Every physician at one time or another wishes that he could quickly recall, group and stratify elements of his past practice and apply that experience toward solving a current problem. In Oncology attempts to use hospital registries for this purpose are often disappointing, as few are computerized and most lack the detail, accuracy, and flexibility to be truly responsive. The development of our current Gynecologic Oncology Tumor registry began in 1982. The final product results from the cooperation of a computer specialist, a registrar, physicians, and nurses. In addition, three independent programs have been incorporated to expand the statistical and reporting functions of the registry. The result is a tumor registry that is the foundation of a clinical research system.  相似文献   
104.
Cytokines are secreted proteins that act as local immunological mediators. Increased seminal cytokine concentrations are associated with fertility problems. The purpose of the present study was to investigate the presence of IL-2alpha, and IL-2beta receptors on fresh and isolated sperm by flow cytometry and transmission electron microscopy. Twenty sperm samples from oligospermic men were incubated with CD25, a mouse monoclonal antibody specific for IL-2alpha-chain receptor, and CD122, a mouse monoclonal antibody specific for IL-2beta-chain receptor. The strong initial fluorescence intensity and, subsequently, a labeling index yielded by CD25 and CD122 decreased in sperm centrifuged on a Percoll gradient (p < .05). The expression of CD25 and CD122 correlated negatively with fresh sperm concentration, but in sperm centrifuged on a Percoll gradient there was no correlation. Labeling with CD25 and CD122 antibody was evident on the head and the middle piece in fresh sperm, while in sperm centrifuged on a Percoll gradient a weak labeling was observed only on the principal piece. The authors have identified and localized cytokine receptors on human sperm for the first time. Cytokine receptors may be involved in the regulation of pathophysiological events in sperm cell functions and male infertility. The exact pathway involved in modulation of these receptors requires further investigation. These results contribute to the understanding of cytokine-sperm relationships.  相似文献   
105.
Neurinomas, also referred to as neurilemmomas and schwannomas, are rare benign tumours of the peripheral nerves. A small percentage of these lesions arise from the brachial plexus. The Authors report two cases of schwannoma arising from the brachial plexus. Such lesions, usually asymptomatic, may cause sensitivity alterations or, less frequently, motor deficits in the involved arm. Tumour enucleation, avoiding damage to any of the nervous fascicles, is the treatment of choice.  相似文献   
106.
107.
This study aimed to ascertain whether extracorporeal photochemotherapy (ECP) is an effective treatment for paediatric patients with refractory graft-versus-host disease (GVHD). From January 1992 to December 2000, 77 children (median age 8.6 years) with either acute (n = 33) or chronic (n = 44) GVHD, resistant to conventional immunosuppressive therapy, were treated with ECP in four Italian paediatric hospitals. After ECP, acute GVHD involving skin, liver and gut responded completely in 76%, 60% and 75% of patients respectively. The 5-year overall survival was 69% for responding patients vs 12% for non-responders (P = 0.001). Among the 44 children with chronic GVHD, 15 (44%) showed a complete response and 10 (29%) a significant improvement after ECP. The 5-year overall survival was 96% for responders vs 58% for non-responders (P = 0.04). Our results suggest that ECP is an effective treatment that may be useful in paediatric patients with either acute or chronic GVHD who have failed to respond to standard immunosuppressive therapy.  相似文献   
108.
Diabetic nephropathy is one of the most frequent causes of end-stage renal disease (ESRD), and, in recent years, the number of diabetic patients entering renal replacement therapy has dramatically increased. The magnitude of the problem has led to numerous efforts to identify preventive and therapeutic strategies. In normoalbuminuric patients, optimal glycemic control (HbA(1c) lower than 7.5%) plays a fundamental role in the primary prevention of ESRD [weighted mean relative risk reduction (RRR) approximately 37% for metabolic control versus trivial renoprotection for intensive anti-hypertensive therapy or ACE-inhibitors (ACE-I)]. In the microalbuminuric stage, strict glycemic control probably reduces the incidence of overt nephropathy (weighted mean RRR approximately 50%), while blood pressure levels below 130/80 mmHg are recommended according to the average blood pressure levels obtained in various studies. In normotensive patients, ACE-I markedly reduce the development of overt nephropathy almost regardless of blood pressure levels; in hypertensive patients, ACE-I are less clearly active (weighted mean RRR approximately 23% versus other drugs), whereas angiotensin-receptor blockers (ARB) appear strikingly renoprotective. Once overt proteinuria appears, it is uncertain whether glycemic control affects the progression of nephropathy. In type 1 diabetes, various anti-hypertensive treatments, mainly ACE-I, are effective in slowing down the progression of nephropathy; in type 2 diabetes, two recent studies demonstrate that ARB are superior to conventional therapy or calcium channel blockers (CCB). In clinical practice, pharmacological tools are not always used to the best benefit of the patients. Therefore, clinicians and patients need to be educated regarding the renoprotection of drugs inhibiting the renin-angiotensin system (RAS) and the overwhelming importance of achieving target blood pressure.  相似文献   
109.
The objective of this cross-sectional study was to evaluate mercury exposure and health status among Munduruku Indians from the community of Sai Cinza, State of Pará, Brazil. The population studied included 330 indians, who submitted to a questionnaire, clinical exams, and collection of hair, blood, urine, and feces. Mercury was measured in hair and fish. Although no person was found to have overt mercury intoxication, the mean levels of mercury in hair were elevated (14.45 micrograms/g for children from 7 to 12 years old, 15.70 micrograms/g for women between 14 and 44 years old, and 14.1 micrograms/g for the remaining population). Mercury levels in fish were below levels recommended by the World Health Organization, but rates of fish consumption were high. These results place this indigenous populations as a group under risk of mercury toxicity from the gold production.  相似文献   
110.
BACKGROUND: Optimal behavioral interventions for sustainable weight loss are uncertain. We therefore conducted a study among overweight/obese women comparing conventional dietary counseling of individuals (counseling-based intervention) to a novel, group-based skill-building intervention. METHODS: Eighty subjects were randomly assigned to either the counseling-based or to the skill-building intervention. Outcomes included weight loss, dietitian hours per group and per unit weight loss, and dollars spent per group and per unit weight lost. RESULTS: Weight loss at 6 months (follow-up rate 61.3%) in the counseling-based group was 8.8 lb (P = 0.0001), and in the skill-building group was 3.8 lb (P = 0.01). A total of 160 dietitian hours were required for the counseling-based group, and 131 for the skilled-building group. The counseling-based group cost an average of $21 per pound lost, while the skill-building cost an average of $48 per pound lost (P = 0.16). CONCLUSIONS: At 6 months, individualized office-based counseling produced more weight loss than a skill-building approach and cost less than half as much per pound of weight loss. Longer-term follow-up is required to determine if, as hypothesized, the skill-building intervention produces more sustainable weight loss.  相似文献   
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