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81.
OBJECTIVE: Polycystic ovary syndrome (PCOS) is a risk factor for type 2 diabetes mellitus and screening for abnormal glucose metabolism has been recommended by an oral glucose tolerance test (OGTT). This procedure is time-consuming and inconvenient, limiting its general use. Therefore, an easy method is wanted to separate PCOS women with normal from those with potentially abnormal glucose metabolism. DESIGN: Simple parameters obtained from 101 consecutive PCOS patients were assessed by receiver operating curve analysis for their ability to predict abnormal glucose metabolism. RESULTS: Comparing discriminating parameters at defined sensitivities revealed that, assessed by homeostasis model assessment (HOMA), insulin resistance (HOMA%S) had the highest specificity. At a cut-off point of 73.1%, HOMA%S had a sensitivity of 95.5% and a specificity of 51.9%. Applying this cut-off separated 59 women who had a high probability of abnormal glucose metabolism from 42 women who were at low risk (less than 2.5%). Fasting insulin was the second-best parameter and had a similar specificity. A screening strategy which applies HOMA%S or fasting insulin could almost halve the number of OGTTs by directing them to those PCOS women most likely to be suffering from abnormal glucose metabolism. The negative predictive value of this strategy was 97%. The strategy was tested and confirmed in a second and independent cohort of 264 PCOS women. CONCLUSIONS: HOMA%S, or to a lesser extent fasting insulin, appears to allow for stratified metabolic screening of PCOS women with OGTT.  相似文献   
82.
AIM: The objective of this study is to provide an overview of the ageing of the nursing workforce and to explore retention strategies centred on the entire professional life and on all age groups. BACKGROUND: The presence of an increasing proportion of ageing workers presents a major challenge to the nursing profession. Evaluation Presentation of theories about the development of a healthy workplace leads to the identification of a framework on which managers can base their management decisions. KEY ISSUES: Examples of incentives relating to the framework are presented which were expressed by both nurses under 50 years of age and those over 50. CONCLUSIONS: Introducing incentives centred on all age groups provides an opportunity to create a healthy workplace for all generations of nurses.  相似文献   
83.
To determine the mechanism underlying pulsatile TSH secretion, 24-h serum TSH levels were measured in three groups of five healthy volunteers by sampling blood every 10 min. The influence of an 8-h infusion of dopamine (200 mg), somatostatin (500 micrograms), or nifedipine (5 mg) on the pulsatile release of TSH was tested using a cross-over design. The amount of TSH released per pulse was significantly lowered by these drugs, resulting in significantly decreased mean basal TSH serum levels. However, pulses of TSH were still detectable at all times. The TSH response to TRH (200 micrograms) tested in separate experiments was significantly lowered after 3 h of nifedipine infusion compared to the saline control value. Nifedipine treatment did not alter basal, pulsatile, or TRH-stimulated PRL secretion. The persistence of TSH pulses under dopamine and somatostatin treatment and the blunted TSH responses to nifedipine infusion support the hypothesis that pulsatile TSH secretion is under the control of hypothalamic TRH. The 24-h TSH secretion pattern achieved under stimulation with exogenous TRH in two patients with hypothalamic destruction through surgical removal of a craniopharyngioma provided further circumstantial evidence for this assumption. No TSH pulses and low basal TSH secretion were observed under basal conditions (1700-2400 h), whereas subsequent repetitive TRH challenge (25 micrograms/2 h to 50 micrograms/1 h) led to a pulsatile release of TSH with fusion of TSH pulses, resulting in a TSH secretion pattern strikingly similar to the circadian variation. These data suggest that pulsatile and circadian TSH secretions are predominantly controlled by TRH.  相似文献   
84.
Relapse after autologous bone marrow transplantation for chronic myelogenous leukemia (CML) can be due either to the persistence of leukemia cells in systemic tissues following preparative therapy, or due to the persistence of leukemia cells in the autologous marrow used to restore marrow function after intensive therapy. To help distinguish between these two possible causes of relapse, we used safety-modified retroviruses, which contain the bacterial resistance gene NEO, to mark autologous marrow cells that had been collected from patients early in the phase of hematopoietic recovery after in vivo chemotherapy. The cells were then subjected to ex vivo CD34 selection following collection and 30% of the bone marrow were exposed to a safety-modified virus. This marrow was infused after delivery of systemic therapy, which consisted of total body irradiation (1,020 cGy), cyclophosphamide (120 mg/kg), and VP-16 (750 mg/m2). RT PCR assays specific for the bacterial NEO mRNA, which was coded for by the virus, and the bcr-abl mRNA showed that in two evaluable CML patients transplanted with marked cells, sufficient numbers of leukemia cells remained in the infused marrow to contribute to systemic relapse. In addition, both normal and leukemic cells positive for the retroviral transgenome persisted in the systemic circulation of the patients for at least 280 days posttransplant showing that the infused marrow was responsible for the return of hematopoiesis following the preparative therapy. This observation shows that it is possible to use a replication-incompetent safety-modified retrovirus in order to introduce DNA sequences into the hematopoietic cells of patients undergoing autologous bone marrow transplantation. Moreover, this data suggested that additional fractionation procedures will be necessary to reduce the probability of relapse after bone marrow transplantation in at least the advanced stages of the disease in CML patients undergoing autologous bone marrow transplantation procedures.  相似文献   
85.
86.
The potential of localized heating as a adjunct to radiation therapy   总被引:1,自引:0,他引:1  
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87.
88.
As a form of opioid maintenance treatment, high-dose buprenorphine is increasingly being used in the United States. On the French market since 1996, it is the most commonly prescribed and frequently employed opioid maintenance treatment. For unknown reasons, the brand-name form is used far more often than the generic form (76–24%). The objective was to show that the patients' levels of addiction were differentiated according to the form of buprenorphine currently being used and to their previous experience of a different form. An observational study in 9 sites throughout France used self-assessment questionnaires filled out in retail pharmacies by all patients to whom their prescribed buprenorphine treatment was being delivered. The 151 canvassed pharmacies solicited 879 patients, of whom 724 completed the questionnaires. Participants were statistically similar to non-participants. The patients using the brand-name form subsequent to experience with the generic form exhibited a more elevated addiction severity index and a higher dosage than brand-name form users with no experience of a different form. Compared to generic users, their doses were higher, their was addiction more severe, and their alcohol consumption was more excessive; they were also more likely to make daily use of psychotropic substances. However, the level of misuse or illicit consumption was similar between these groups. Preferring the brand-name buprenorphine form to the generic form is associated with a higher level of severe addiction, a more frequent need for daily psychotropics, and excessive drinking; but the study was unable to show a causal link.  相似文献   
89.
90.

Background and purpose

Undifferentiated follicular and anaplastic thyroid tumours often respond poorly to radiotherapy and show increased metastatic potential. We evaluated radiation-induced effects on metastasis in thyroid carcinoma cells and tumours, mechanistically focusing on phosphatidylinositide 3-kinase (PI3K) and associated pathways.

Material and methods

Migration was analysed in follicular (FTC133) and anaplastic (8505c) cells following radiotherapy (0–6 Gray) with concomitant pharmacological (GDC-0941) or genetic inhibition of PI3K. Hypoxia-inducible factor-1 (HIF-1)-activity was measured using luciferase reporter assays and was inhibited using a dominant-negative variant. Activation and subcellular localisation of target proteins were assessed via Western blot and immunofluorescence. In vivo studies used FTC133 xenografts with metastatic lung dissemination assessed ex vivo.

Results

Radiation induced migration in a HIF-dependent manner in FTC133 cells but decreased migration in 8505c’s. Post-radiation HIF-activity correlated with migratory phenotype. PI3K-targeting inhibited migration under basal and irradiated conditions through inhibition of HIF-1α, Rho-GTPase expression/activity and localisation whilst having little effect on src/FAK. In vivo, radiation induced PI3K, HIF, Rho-GTPases and src but only PI3K, HIF and Rho-GTPases were inhibited by GDC-0941. Co-treatment with GDC-0941 and radiation significantly reduced metastatic dissemination versus radiotherapy alone.

Conclusions

Radiation modifies metastatic characteristics of thyroid carcinoma cells, which can be successfully inhibited by targeting PI3K using GDC-0941 in vitro and in vivo.  相似文献   
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