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BACKGROUND: Bisphosphonates can prevent bone mineral density loss after renal transplantation, but their effect on trabecular mineralization and bone morphology, two key factors of bone stability, remains unknown. METHODS: In a 6-month, randomized, placebo-controlled study, 20 kidney transplant recipients received either 4 mg zoledronic acid or placebo twice within 3 months after engraftment. At transplantation and after 6 months, mean trabecular calcium concentration and trabecular morphometry were measured in bone biopsies. Bone mineral density (BMD) of the femoral neck and the lumbar spine were evaluated by dual-energy x-ray absorptiometry, and serum biochemical markers of bone metabolism were determined monthly. RESULTS: Trabecular calcium content increased significantly in the zoledronic acid group, but remained unchanged in the placebo group. BMD at femoral neck showed no change in the zoledronic acid group, but decreased in the placebo group. BMD of the lumbar spine was increased in the zoledronic acid group without change in the placebo group. High-turnover bone disease resolved similarly in both groups, as evidenced by a significant decrease of eroded bone surface, osteoclast and osteoblast surface. Serologic markers of bone formation and resorption were significantly lower in zoledronic acid-treated patients throughout the study. Kidney transplant function was stable after zoledronic acid therapy. CONCLUSIONS: Our results show that administration of zoledronic acid improves the calcium content of cancellous bone after kidney transplantation. The beneficial effect of bisphosphonate therapy is further evidenced by an increase of lumbar spine BMD, and stabilization of femur BMD.  相似文献   
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OBJECTIVES

To evaluate the potential of 11C‐choline‐positron emission tomography (PET)/computed tomography (CT) for planning surgery in patients with prostate cancer and prostate‐specific antigen (PSA) relapse after treatment with curative intent.

PATIENTS AND METHODS

We retrospectively reviewed the charts of 10 patients with PSA recurrence after either external beam radiation (two) or radical retropubic prostatectomy (eight) for prostate cancer, and who had a laparoscopic lymphadenectomy for suspicious lymph nodes detected on 11C‐choline‐PET/CT. The histological results and PET/CT findings were compared.

RESULTS

In all, 22 suspicious lymph nodes were found on PET/CT, and 14 on conventional CT or magnetic resonance imaging. Comparing the conventional imaging showed concordance in 13 lymph nodes. Three of the 10 patients had no metastatic lymph node disease on definitive histology. The mean (sd ) PSA level for these patients was 1.0 (0.4) ng/mL, whereas that in patients with lymph node metastases was 15.1 (9.2) ng/mL (statistically significant difference, P < 0.05). The positive predictive value was seven of 10. All of the patients initially regressed, with PSA increases after lymphadenectomy. Two of the patients are being managed by watchful waiting, two had radiotherapy of the prostate fossa and two had chemotherapy with docetaxel. Four patients were treated by hormone‐deprivation therapy. After a mean (sd ) follow up of 11 (7) months, one patient died, one has PSA progression, but none of those with negative histology has clinical signs of local recurrence.

CONCLUSIONS

11C‐choline‐PET is a valuable tool for detecting recurrent prostate cancer, but the limited positive predictive value should lead to a critical interpretation of the results.  相似文献   
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Two questionnaire surveys about satisfaction with hospital services were carried out among HIV-infected people in Flanders. In a first survey (CIRCA '93 study) between 1993 and 1995, before highly active antiretroviral treatment (HAART) was available, questionnaires were distributed by HIV treatment centres, general practitioners and HIV support organizations: 315 people with HIV infection completed the questionnaire. The level of patient satisfaction was generally higher with services at university hospitals than at general hospitals. Most patients preferred to be hospitalized in a ward specialized in HIV care. Contact with other HIV-infected patients was generally experienced as supportive. The second survey included 34 patients with HIV-infection and 83 patients with lung disease. They were admitted to the same ward at the Antwerp University Hospital, between July 1996 and July 1997. Patients with HIV infections were expecting more services than patients with lung disease. Both studies showed that HIV-infected patients wanted to be actively involved in diagnostic and treatment decisions. The multidisciplinary approach, offered by the Antwerp University Hospital, was widely appreciated by patients and could be used as an example for organizing patient care for other diseases.  相似文献   
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International guidelines for the treatment of human immunodeficiency virus (HIV) infection change rapidly. They are mainly based on results from large-scale randomized clinical trials, but also on hypotheses. The objective of the study was to look at the use of antiretrovirals (ARVs) in different HIV treatment centres in Europe. Between August 1996 and September 1997 self-administered anonymous questionnaires were distributed to persons with HIV infection at inpatient and outpatient departments in 11 European countries; 1,366 people completed the questionnaire. Important differences in use of ARVs were noted between different centres. Zidovudine was the drug that was used predominantly in all countries and by 77% of all patients; the use of didanosine, zalcitabine and stavudine differed widely. Use of ARVs was found to be lower for people who reported intravenous drug use (compared to homosexual transmission), people with a low education level, and those with a monthly income lower than 992 Euro. The use of a protease inhibitor containing ARV treatment regimen was significantly lower in the centres in the south of Europe. Between 1996 and 1997, many persons with HIV infection in Europe received a suboptimal ARV treatment regimen. Use of ARVs should be improved for intravenous drug users, persons with lower educational level and lower income.  相似文献   
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