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101.
Using 600 clinical specimens, we compared the concordance of four methods for carcinoembryonic antigen: the Roche RIA (I); the Roche EIA (II); Hybritech EIA (III); and Abbott EIA (IV). EDTA-treated plasma was used for Methods I and II and serum for Methods III and IV. However, no significant difference was found between results for serum and plasma in Method II. The normal reference interval (in micrograms/L) was I (222 specimens), 1.94 +/- 1.54; II (57 specimens), 0.8 +/- 0.5; III (100 specimens), 2.94 +/- 2.47; and IV (614 specimens), less than 5.0. The precision of all four methods was acceptable. Concordance among all of the methods exceeded 90%.  相似文献   
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This paper reflects on a research project funded by a consortium of leading sheltered housing (SH) providers and their regulatory body, the Housing Corporation. The project aimed to ascertain which aspects of SH older people perceived to be central to their satisfaction and the methods they judged most appropriate to measuring this. We outline key policy developments of importance to SH (specifically the development of performance measurement regimes), and changes in the nature of SH, which are driving providers to re‐evaluate how they measure user satisfaction. We discuss the aims of the project, our methodology and findings, and conclude by raising critical questions about the process of measuring satisfaction within an increasingly managerialised housing system. We argue that this favours standardised methods of information gathering (such as questionnaires) rather than engage with clients in order to develop methods and systems capable of eliciting qualitative issues of concern to them. Our conclusions are, we believe, applicable to health and social care provision, where similar tensions exist around performance measurement and user satisfaction.  相似文献   
105.
Background. Vitiligo is an acquired skin disorder that is characterized by well-defined, often symmetric white patches. Although current therapeutic modalities are directed toward increasing melanocyte melanin production, few treatment modalities address the immunologic nature of the disease.
Objective. To determine whether excimer laser, a known therapeutic modality, in combination with tacrolimus, a topical immunomodulator, accelerate response time and/or improve the degree of response in patients with this disorder.
Methods. Eight subjects diagnosed with vitiligo were recruited to participate in this institutional review board–approved double-blind, placebo-controlled study. Twenty-four symmetric vitiliginous patches (elbows, knees) from eight subjects received excimer laser treatment three times per week for 24 treatments or 10 weeks. Additionally, topical tacrolimus 0.1% ointment (Protopic) and placebo (Aquaphor) were applied to randomized patches (left or right) twice daily throughout the length of the trial. Vitiliginous patches were monitored with photographs at baseline, every 2 weeks, and 6 months after treatment. Biopsies were performed on subjects with significant results.
Results. Twenty vitiliginous patches from six subjects qualified for evaluation. Fifty percent of patches treated with combination excimer laser and tacrolimus achieved a successful response (75% repigmentation) compared with 20% for the placebo group. Subjects who responded successfully repigmented faster (19%) with combination therapy compared with excimer laser alone. Additionally, three subjects experienced transient hyperpigmentation in lesions treated with combination therapy.
Conclusion. Combining topical immunomodulators with known phototherapeutic modalities may represent a key advancement in the treatment of disease.  相似文献   
106.
The receptor tyrosine kinase (RTK) Ret is activated by the formation of a complex consisting of ligands such as glial cell line-derived neurotrophic factor (GDNF) and glycerophosphatidylinositol-anchored coreceptors termed GFRalphas. During activation, Ret translocates into lipid rafts, which is critical for functional responses to GDNF. We found that Ret was rapidly ubiquitinated and degraded in sympathetic neurons when activated with GDNF, but, unlike other RTKs that are trafficked to lysosomes for degradation, Ret was degraded predominantly by the proteasome. After GDNF stimulation, the majority of ubiquitinated Ret was located outside of lipid rafts and Ret was lost predominantly from nonraft membrane domains. Consistent with the predominance of Ret degradation outside of rafts, disruption of lipid rafts in neurons did not alter either the GDNF-dependent ubiquitination or degradation of Ret. GDNF-mediated survival of sympathetic neurons was inhibited by lipid raft depletion, and this inhibitory effect of raft disruption on GDNF-mediated survival was reversed if Ret degradation was blocked via proteasome inhibition. Therefore, lipid rafts sequester Ret away from the degradation machinery located in nonraft membrane domains, such as Cbl family E3 ligases, thereby sustaining Ret signaling.  相似文献   
107.
Symptoms of obstructive lung disease in domestic cleaners have been related to the use of bleach and other irritant cleaning products. The short-term effects of cleaning exposures on respiratory symptoms and peak expiratory flow (PEF) were investigated in domestic cleaners with respiratory disorders. In a panel study, 43 female domestic cleaners with a recent history of asthma and/or chronic bronchitis completed a 2-week diary, collecting information on respiratory symptoms, PEF and cleaning exposures. Mixed regression models were used to assess daily changes in symptoms and PEF associated with specific cleaning exposures. The probability of having work-related asthma was individually assessed by a computerised diagnostic system and an occupational asthma expert. Lower respiratory tract symptoms were more common on working days and were predominantly associated with exposure to diluted bleach, degreasing sprays/atomisers and air fresheners. Associations with upper respiratory tract symptoms and PEF were less apparent. Eleven (30%) subjects scored positively for work-related asthma. It is concluded that exposure to certain irritant cleaning products aggravates lower respiratory tract symptoms in female domestic cleaners with asthma or chronic bronchitis.  相似文献   
108.
The Effect of Cuts in Medicare Reimbursement on Hospital Mortality   总被引:1,自引:0,他引:1  
Objective. To determine if patients treated at hospitals under different levels of financial strain from the Balanced Budget Act (BBA) of 1997 had differential changes in 30-day mortality, and whether vulnerable patient populations such as the uninsured were disproportionately affected.
Data Source. Hospital discharge data from all general acute care hospitals in Pennsylvania from 1997 to 2001.
Study Design. A multivariate regression analysis was performed retrospectively on 30-day mortality rates, using hospital discharge data, hospital financial data, and death certificate information from Pennsylvania.
Data Collection. We used 370,017 hospital episodes with one of four conditions identified by the Agency for Healthcare Research and Quality as inpatient quality indicators were extracted.
Principal Findings. The average magnitude of Medicare payment reduction on overall net revenues was estimated at 1.8 percent for hospitals with low BBA impact and 3.6 percent for hospitals with a high impact in 1998, worsening to 2 and 4.8 percent, respectively, by 2001. Operating margins decreased significantly over the time period for all hospitals ( p <.05). While unadjusted mortality rates demonstrated a disproportionate rise in mortality for patients from high impact hospitals from 1997 to 2000, adjusted analyses show no consistent, significant difference in the rate of change in mortality between high-impact and low-impact hospitals ( p =.04–.94). Similarly, uninsured patients did not experience greater increases in mortality in high-impact hospitals relative to low-impact hospitals.
Conclusions. An analysis of hospitalizations in the Commonwealth of Pennsylvania did not find an adverse impact of increased financial strain from the BBA on patient mortality either among all patients or among the uninsured.  相似文献   
109.
The combination of insulin-like growth factor-I and platelet-derived growth factor-BB has previously been shown to stimulate healing of soft tissue wounds and the formation of bone and ligament around teeth. The purpose of the present study was to evaluate the effects of platelet-derived growth factor-BB and insulin-like growth factor-I individually and in combination on the healing of osseous wounds. Four standardized cortical wounds were created in each tibia of 11 adult Yucatan miniature pigs. The wounds in one tibia per animal were treated with either purified recombinant human insulin-like growth factor-I, platelet-derived growth factor-BB, or both in a methylcellulose gel. The wounds in each contralateral tibia received placebo gel alone. Coded serial sections of each wound were evaluated by computer-aided histomorphometry 21 days after surgery. The area and perimeter of the newly formed mineralized callus, the thickness of the total callus, and the percentage of mineralized tissue within the callus were significantly increased compared with the values of matched controls only in wounds treated with a combination of insulin-like growth factor-I and platelet-derived growth factor-BB. No significant differences in the measured parameters of callus formation were found in wounds treated with either insulin-like growth factor-I or platelet-derived growth factor-BB alone. Cartilage was present only in sites treated with insulin-like growth factor-I alone. These results suggest that the combination of platelet-derived growth factor-BB and insulin-like growth factor-I stimulates bone formation in wounds in long bones of adult animals and that these growth factors act via different pathways during the repair process.  相似文献   
110.
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