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1.
We report the case of a patient with a 13-year history of pemphigus vulgaris (PV) treated with immunosuppressive agents, prednisone and mycophenolate mofetil who had developed lesions of Kaposi's sarcoma (KS) on a sole plaque of PV that had been previously treated with intralesional injections of steroids. The lesions were surgically removed and polymerase chain reaction (PCR) demonstrated human herpesvirus-8 (HHV-8) DNA. There were neither recurrences nor later dissemination of KS following gradual decrease of the immunosuppressive therapy. We suggest that the treatment with intralesional steroids may have influenced the local reactivation of a latent infection of the virus, determining the appearance of this localized KS.  相似文献   
2.
Reconstruction of musculoskeletal defects about the knee for tumor   总被引:6,自引:1,他引:5  
One of the most challenging problems of limb salvage is a large tumor involving the knee joint. Since 1970, 79 patients, ranging in age from 14 to 74 years (mean, 27 years), have had reconstruction of the knee after en bloc resection of a primary bone tumor. Sixty-one patients had lesions involving the distal femur, with a mean resection length of 13.5 cm, and 18 patients had lesions involving the proximal tibia, with a mean resection length of 10.5 cm. Thirty-nine patients had malignant lesions, of which osteosarcomas predominated, and 40 patients had benign tumors, of which giant cell tumors were the most prevalent. Reconstruction was done with a custom total knee arthroplasty in 41 patients, a resection arthrodesis in 27, and an allograft in 11. The functional results were graded according to the rating system devised by the Musculoskeletal Tumor Society. of the patients with resection arthroplasty, 70% had a good or excellent rating, although ten required revision. Of the patients with resection arthrodesis, 74% had a good or excellent rating, as did 55% of the patients with osteochondral allografts. When a limb salvage procedure is done, careful consideration must be given to the type of procedure chosen to reconstruct the knee. This decision is based on a number of factors related to the tumor and the patient. Although these various procedures promise functional restoration, the reconstructive procedure should be individualized and designed to meet the needs of the patient.  相似文献   
3.
By convention, establishing a physiologic role for a gut peptide requires demonstration of biologic activity that can be reproduced by exogenous administration of the peptide in amounts that yield plasma concentrations that are not higher than those found after a meal. We have tested the hypothesis that the combined action of two inhibitory peptides may lower the effective doses of each. We further hypothesize that combined peptide responses may be responsible for the action of peptide hormones that have been difficult to demonstrate as physiologically relevant mediators, when examined as independently acting substances. In conscious dogs prepared with chronic pancreatic cannulas, stimulated pancreatic exocrine secretions were depressed in a dose-related manner by intravenous infusions of calcitonin (CT) and calcitonin gene-related peptide (CGRP). Doses of 2.0 nmol/kg/hr of both CT and CGRP yielded maximal inhibition of stimulated secretions of both bicarbonate (greater than 85% inhibition) and protein (greater than 55% inhibition). The lowest effective dose for either CT or CGRP, given alone, was 0.75 nmol/kg/hr, but when infused simultaneously, each at the subthreshold dose of 0.50 nmol/kg/hr, significant inhibition of protein and bicarbonate secretion was achieved. Combined infusions of the submaximal dose of 0.75 nmol/kg/hr resulted in an enhanced inhibitory response. To prove that this effect is not simply combined activation of a common receptor, we tested peptide YY (0.1 to 0.5 nmol/kg/hr) combined with CGRP and obtained similar results. Because a meal simultaneously releases a large number of active peptides, we speculate that such potentiated responses do occur physiologically. Cooperative interaction with other agents may be the primary mode of action for certain gut peptides.  相似文献   
4.
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
5.
6.
A retrospective review of 23 patients with osteoblastoma was undertaken in an attempt to answer questions concerning the aggressiveness and potential malignancy of this tumour. Demographic information confirmed that recorded in the literature. There was no suggestion of malignant potential, but, significantly, one tumour persisted, with local recurrence after 11 operations over a period of 27 years. A second tumour, a spinal lesion, occurred (still in a benign form) after a symptom-free period of 17 years. Recognition of aggressive features clinically, radiologically and histologically suggests the need for more aggressive surgical treatment, and late recurrence indicates the need for a more guarded prognosis and longer follow-up.  相似文献   
7.
8.
Iliac-vessel injury from total hip arthroplasty is associated with hemorrhagic complications and an increased death rate. The authors identified seven patients who had severe medial displacement of the acetabular prosthesis and associated vascular injury to the iliac vessels after total hip replacement. One patient had two hip replacements. Preoperative findings included a pelvic mass (three hips), pelvic pain (eight), radiologic evidence of cement in the pelvis (three) and the acetabular prosthesis in the pelvis (eight), computed tomographic evidence of cement in the pelvis and proximity of the prosthesis to the iliac vessels (four), and arteriography showing displacement or compression of the iliac vessels (seven). Operative management in all cases involved medial exposure, mobilization and repair of the iliac vessels before revision of the hip prosthesis. Postoperative complications were deep vein thrombosis (three), in spite of prophylaxis, and occlusion of a vein interposition graft (one) requiring placement of a femoral crossover graft. There were no deaths, amputations or hemorrhagic complications. The authors advocate preoperative identification of patients who have iliac-vessel involvement by their total hip prosthesis and initial medial extraperitoneal exposure and repair of these vessels before removal of the displaced acetabular prosthesis.  相似文献   
9.
SUMMARY A young patient presenting with splenomegaly and hypersplenism was inadvertently found to have selective IgA deficiency. There were no symptoms of immunodeficiency and the patient responded well to splenectomy, with return of blood counts to normal without adverse effects. No other cause for the hypersplenism was found. We postulate selective IgA deficiency as a cause of splenomegaly and hypersplenism.  相似文献   
10.
Background: A growing body of research suggests that older exercisers prefer to exercise alone rather than in group-based settings. One limitation of these studies, however, has been that researchers have failed to take into account the age-related characteristics of groups when asking adults about their preferences for exercise settings.Purpose: The overall purpose of this study was to examine the exercise preferences of 947 adults for involvement in standard exercise classes populated by participants from various categories across the age spectrum.Results: The results revealed that when faced with the prospect of exercising with considerably older or younger exercisers, participants found such an exercise context to be largely unappealing. However, in accordance with the basic tenets of self-categorization theory, the results revealed that older and younger adults alike express a positive preference for exercising in standard exercise classes comprised of similarly aged participants.Conclusions: The findings of this study challenge a growing call for exercise interventions for older adults to be primarily directed at the individual-level, and suggest that group-related intervention strategies may indeed be attractive to older exercisers.  相似文献   
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