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991.
Implementation models, such as the national Put Prevention Into Practice program, have produced small to moderate changes in the delivery of preventive services in primary care. More recently, researchers concluded that guides and tools, such as the PPIP toolkit, are helpful, but are not sufficient to facilitate substantive change in clinical preventive practice. Successful implementation of clinical preventive services, according to the Texas Department of Health-PPIP (TDH-PPIP) initiative, involves creating or altering systems to produce change in service delivery for a specific setting. This article describes the ways in which the guidelines and instruments that were developed and refined through the collaborative efforts among public and private health systems were used to implement systems change and improve clinical preventive services at one community primary health care clinic in Texas. The process and empirical results of using the TDH-PPIP Implementation Model in the field are also presented, as well as a discussion of one-year evaluation data.  相似文献   
992.
OBJECTIVE: To determine the cause of acute illness on August 30, 2000, among patients at an outpatient dialysis center (center A). DESIGN: We performed a cohort study of all patients receiving dialysis on August 30, 2000; reviewed dialysis procedures; and analyzed dialysis water samples using microbiologic and chemical assays. SETTING: Dialysis center (center A). PATIENTS: A case-patient was defined as a patient who developed chills within 5 hours after starting hemodialysis at center A on August 30, 2000. RESULTS: Sixteen (36%) of 44 patients at center A met the case definition. All case-patients were hospitalized; 2 died. Besides chills, 15 (94%) of the case-patients experienced nausea; 12 (75%), vomiting; and 4 (25%), fever. Illness was more frequent on the second than the first dialysis shift (16 of 20 vs 0 of 24, P < .001); no other risk factors were identified. The center's water treatment system had received inadequate maintenance and disinfection and a sulfurous odor was noted during sampling of the water from the reverse osmosis (RO) unit. The water had elevated bacterial counts. Volatile sulfur-containing compounds (ie, methanethiol, carbon disulfide, dimethyldisulfide, and sulfur dioxide) were detected by gas chromatography and mass spectrometry in 8 of 12 water samples from the RO unit and in 0 of 28 samples from other areas (P < .001). Results of tests for heavy metals and chloramines were within normal limits. CONCLUSIONS: Parenteral exposure to volatile sulfur-containing compounds, produced under anaerobic conditions in the RO unit, could have caused the outbreak. This investigation demonstrates the importance of appropriate disinfection and maintenance of water treatment systems in hemodialysis centers.  相似文献   
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OBJECTIVE: In our study we evaluated the frequency of three SNPs (-52 G/A, -44 C/G; -20 G/A) in the 5' UTR of DEFB-1 gene, in a cohort of 130 HIV-1 infected mothers and their children, collected by the Italian group SIGO in Obstetrics and Gynecology. METHODS: The three SNPs (-52 G/A, -44 C/G; -20 G/A) in the 5' UTR of DEFB-1 gene were genotyped by direct sequencing of PCR products. RESULTS: The C allele at position -44 was shown to be significantly different in both HIV-1 positive mothers and their children when compared to the healthy controls. The odds ratio for -44 C allele in children born to HIV-1 infected mothers is 7.09 (confidence interval 3.38-15.3) while the odds ratio for this allele in HIV-1 infected mothers is 6.42 (confidence interval 3.14-13.4). CONCLUSIONS: Our results evidence a high frequency of the -44 CC allele in HIV-1 infected mothers and their children with augmented potential risk of maternal fetal transmission. This potential vertical transmission risk has been successfully prevented by antiretroviral drug treatment and cesarian section of the HIV-1 positive mothers.  相似文献   
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PURPOSE: Absolute lymphocyte count recovery at day 15 (ALC-15) post-autologous stem cell transplantation (ASCT) is a powerful prognostic indicator for survival for multiple hematologic malignancies and metastatic breast cancer. The relationship of ALC-15 with clinical outcomes in primary systemic amyloidosis is unknown. EXPERIMENTAL DESIGN: We evaluated 145 consecutive patients with primary systemic amyloidosis who underwent ASCT at the Mayo Clinic from 1996 to 2003. The ALC-15 threshold was set at 500 cells/microL based on our previous observations. RESULTS: The median patient follow-up was 22 months (range, 3-87 months). Higher hematologic complete response was observed in patients with an ALC-15 > or = 500 cells/microL compared with patients with an ALC-15 < 500 cells/microL (41% versus 21%, P < 0.0008, respectively). The median overall survival and progression-free survival times were significantly better for the 59 patients that achieved an ALC-15 > or = 500 cells/microL compared with 86 patients with ALC-15 < 500 cells/microL (not reached versus 53 months, P < 0.0003 and not reached versus 27 months, P < 0.0001, respectively). Multivariate analysis showed ALC-15 to be an independent prognostic factor for overall survival and progression-free survival. CONCLUSIONS: ALC-15 > or = 500 cells/microL is associated with significantly improved clinical outcomes following ASCT in patients with primary systemic amyloidosis.  相似文献   
998.
OBJECTIVES: Intestinal alkaline sphingomyelinase, by exerting a major role in dietary sphingomyelin digestion, is responsible for the generation of messengers able to trigger the rapid turnover and apoptosis in intestinal epithelial cells. Markedly reduced mucosal alkaline sphingomyelinase activity has been associated with human colorectal neoplasms. The aim of this study was to analyze the alkaline sphingomyelinase activity in feces from healthy subjects and colorectal adenocarcinoma patients and to correlate it with the enzyme activity in intestinal tissues. MATERIALS AND METHODS: The enzyme activity was measured both in the intestinal samples from 12 healthy controls and 51 patients with colorectal adenocarcinoma (tumoral and paratumoral tissue) and in the fecal samples of 34 healthy subjects and 29 patients with adenocarcinoma. The relation between sphingomyelinase activity and Dukes' stage, cell differentiation degree, age, and gender was also analyzed. RESULTS: Alkaline sphingomyelinase was significantly decreased (P < 0.001; mean reduction >90%) in tumoral intestinal mucosa of patients compared with controls independently of Dukes' stage and tumor differentiation grade. Interestingly, the enzyme activity in histologically normal paratumoral tissues was statistically lower than control samples (P < 0.001). As occurs in neoplastic tissues, a relevant mean reduction (P < 0.0001; almost 90%) of alkaline sphingomyelinase was revealed in stool samples from tumor patients when compared with controls. CONCLUSION: These findings may have implications for cancer biology and perhaps also for the design of clinical test, thus suggesting that the fecal sphingomyelinase activity could really reflect the human intestinal mucosa enzyme level and could represent a new marker for human colorectal adenocarcinoma, mainly taking into account its early appearance in intestinal neoplasms.  相似文献   
999.
PURPOSE: Point mutations within the ABL kinase domain of the BCR-ABL gene have been associated with clinical resistance to imatinib mesylate in chronic myeloid leukemia (CML) patients. To shed further light on the frequency, distribution, and prognostic significance of ABL mutations, we retrospectively analyzed a homogeneous cohort of late chronic phase CML patients who showed primary cytogenetic resistance to imatinib. PATIENTS AND METHODS: Using denaturing high-performance liquid chromatography (D-HPLC) and sequencing, we screened for ABL mutations in a total of 178 bone marrow and/or peripheral blood samples from 40 late chronic phase CML patients homogeneously treated with imatinib 400 mg/d, who did not reach a major cytogenetic response at 12 months. RESULTS: Mutations were found in 19 of 40 patients (48%). Mutations were already detectable by D-HPLC at a median of 3 months from the onset of therapy. The presence of a missense mutation was significantly associated with a greater likelihood of subsequent progression to accelerated phase/blast crisis (P = .0002) and shorter survival (P = .001). Patients carrying mutations falling within the P-loop seemed to have a particularly poor outcome in terms of time to progression (P = .032) and survival (P = .045). CONCLUSION: Our results show that, irrespective of the hematologic response, monitoring for emerging mutations in the first months of therapy may play a role in detecting patients with worse prognosis, for whom a revision of the therapeutic strategy should be considered.  相似文献   
1000.
Referrals to genetics services are becoming increasingly common for patients who are diagnosed with early-onset colorectal cancer (CRC) or patients who have a family history of CRC. Microsatellite instability (MSI) testing and immunohistochemical analysis (IHC) of the patient’s tumor tissue, which assess indirectly the cellular status of DNA mismatch repair, have proven important tools for geneticists and genetic counselors to determine whether or not these individuals may be at risk for an inherited cancer syndrome, Lynch syndrome (a subset of hereditary nonpolyposis colorectal cancer). The application of tumor MSI/ IHC also extends to the group of providers involved in the diagnosis and management of CRC, demonstrating the growing clinical applicability of MSI/IHC testing. This review discusses the clinical utility of MSI/IHC analysis, including its benefits and limitations, and addresses some of the current debates surrounding testing.  相似文献   
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