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81.
PURPOSE: To assess the clinical and economic effects of disease management in patients with chronic diseases. METHODS: Electronic databases were searched for English-language articles from 1987 to 2001. Articles were included if they used a systematic approach to care and evaluated patients with chronic disease, reported objective measurements of the processes or outcomes of care, and employed acceptable experimental or quasi-experimental study designs as defined by the Cochrane Effective Practice and Organization of Care Group. RESULTS: Two reviewers evaluated 16,917 titles and identified 102 studies that met the inclusion criteria. Identified studies represented 11 chronic conditions: depression, diabetes, rheumatoid arthritis, chronic pain, coronary artery disease, asthma, heart failure, back pain, chronic obstructive pulmonary disease, hypertension, and hyperlipidemia. Disease management programs for patients with depression had the highest percentage of comparisons (48% [41/86]) showing substantial improvements in patient care, whereas programs for patients with chronic obstructive pulmonary disease (9% [2/22]) or chronic pain (8% [1/12]) appeared to be the least effective. Of the outcomes more frequently studied, disease management appeared to improve patient satisfaction (71% [12/17]), patient adherence (47% [17/36]), and disease control (45% [33/74]) most commonly and cost-related outcomes least frequently (11% to 16%). CONCLUSION: Disease management programs were associated with marked improvements in many different processes and outcomes of care. Few studies demonstrated a notable reduction in costs. Further research is needed to understand how disease management can most effectively improve the quality and cost of care for patients with chronic diseases.  相似文献   
82.
BACKGROUND: A photochemical treatment (PCT) process utilizing amotosalen hydrochloride and long wavelength UVA light has been developed to inactivate pathogens in PLTs. This study investigated the effects of amotosalen/UVA treatment on free and latent murine CMV (MCMV) in PLT preparations using a murine model of transfusion-transmitted CMV (TT-CMV). STUDY DESIGN AND METHODS: In a model of latent MCMV infection, "donor" mice received 1 x 10(6) plaque-forming units (PFUs) MCMV and were rested 14 days. Subsequently harvested, pooled, and washed WBCs were PCR positive for MCMV. Murine WBC doses of 1 x 10(4), 1 x 10(5), and 1 x 10(6) were added to human apheresis PLTs in 35 percent autologous plasma and 65 percent PLT AS (PAS). The WBC-PLT products were treated with 150 micro mol/L amotosalen and 0.6 J per cm2 UVA and transfused via tail vein injection into recipient mice. Recipients were killed on Day 14. Blood and spleens were collected and assayed for MCMV by PCR. In a parallel model of active infection with free virus, human PLT in 35 percent autologous plasma and 65 percent PAS were dosed with 1 x 10(5) and 1 x 10(6) PFUs of MCMV. All other procedures were as described above. RESULTS: In the absence of amotosalen/UVA-pretreatment, transfusion of PLT latently or actively infected with MCMV produced TT-CMV in a dose-dependent fashion. In contrast, all transfusion recipients of identical PLT preparations pretreated with amotosalen/UVA were uniformly PCR negative for MCMV (abrogation of TT-CMV; p < 0.05). CONCLUSIONS: PCT of PLT preparations with the specified doses of amotosalen hydrochloride and UVA light prevents transfusion transmission of free and latent MCMV in a murine model. These results suggest that PCT of human PLTs with amotosalen/UVA should also effectively abrogate TT-CMV in the clinical setting.  相似文献   
83.
Activated forms of the protooncogenec-raf have been found to transform established lines of rodent fibroblasts after transfection with DNA from several human and rat tumors. Using Southern blot analysis of DNAs from rat × mouse somatic cell hybrids, we have mappedc-raf to rat chromosome 4. An exogenous sequence that was found juxtaposed toc-raf within transforming DNA originally derived from a rat hepatocellular carcinoma was localized to chromosome 13.  相似文献   
84.
Independent component analysis (ICA) is a novel technique that can separate statistically independent elements from complex signals. It has demonstrated its utility in separating artifacts and analyzing interictal discharges in EEG. ICA has been used recently in ictal recordings, showing the possibility of isolating the ictal activity. The goal of our study was to analyze focal seizures with ICA, decomposing the elements of the seizures to understand their genesis and propagation, and to differentiate between various types of focal seizures. We studied 26 focal seizures of temporal, frontal, or parietal origin. Only seizures with suspected focal onset were included in the study. The EEG recordings were acquired by using standard video-EEG equipment, with scalp electrodes. All the off-line analysis was carried out on a PC by means of specific software developed in the Matlab environment. ICA components were calculated with the use of the JADE (Joint Approximate Diagonalization of Eigen-matrices) algorithm. The decomposition of the seizures varied according to the EEG seizure pattern. In the seizures with focal rhythmic theta slow or sharp waves, the rhythmic activity was separated into one to five components, having an initial component with a clear concordance with the focus, whereas the others had an onset a few milliseconds later and corresponded to neighboring areas. In the 6 frontal seizures with regional rhythmic low voltage fast activity, 4 to 10 components were found, practically with a simultaneous timing, having a frontal distribution. In the three frontal seizures with a diffuse attenuation of the EEG signal, it was not possible to differentiate components of cerebral origin from the components of muscle artifact. ICA is an interesting tool to study the nature of focal seizures. The results depend on the EEG pattern. In the seizures with a clear EEG focal pattern, ICA may be useful to separate components of the ictal onset from the propagated activity.  相似文献   
85.
57 cervico-prostatic incisions have been performed, for prostatic hypertrophy in 56 cases and for dysuria without prostatic hypertrophy in one case. 36 patients underwent a mono-incision and 21 had a bi-incision. The operative technique is simple and the results are satisfactory. After 3 months, the dysuria was improved in 93.5% of cases and the pollakiuria was improved in 92.8% of cases. In 20 patients in whom the quality of ejaculation was defined prior to the operation, this persisted after the operation in 17 cases (85%); it was normal in 8 cases and diminished in 9 cases.  相似文献   
86.
The BDII rat is genetically predisposed to hormone-dependent endometrial adenocarcinoma and was used to model human cancer. Tumors arising spontaneously in strain crosses involving BDII rats were analyzed by means of comparative genome hybridization. The most common aberration was amplification of the proximal region of rat chromosome 4, centered around bands q12-q22. The copy numbers of 15 cancer-related genes from the region were examined in tissue cultures of 11 endometrial carcinomas (10 endometrial adenocarcinomas and 1 endometrial squamous cell carcinoma) and one peritoneal mesothelioma. Amplification in rat chromosome 4 was detected in six tumors (50%), five of which carried two separate amplified regions, situated at 4q12-q13 and 4q21-q22, interrupted by a nonamplified segment at 4q13-q21.1. The genes Cdk6 (cyclin-dependent kinase 6) and Met (hepatocyte growth factor receptor) were located in the core of each amplified region and were amplified most recurrently and at the highest levels among the genes tested. Using fluorescence in situ hybridization on tumor metaphases, it was observed that the amplified Cdk6 and Met sequences were situated on typical homogeneously staining regions (HSRs). In three tumors, both genes were amplified in the same HSRs, whereas in two tumors, the amplified sequences of each gene were situated in separate HSRs. In addition, Cdk6 and Met amplification was consistently associated with a corresponding increase in gene expression, suggesting that the two genes might represent the targets for the amplifications. In the sixth tumor, which carried amplified sequences of Met but not of Cdk6, coexpression of Met and the normally silent hepatocyte growth factor gene (Hgf; the ligand of Met) was observed. This finding suggests that an autocrine signaling circuit might be operating in this particular tumor. Taken together, our findings suggest that up-regulation of Cdk6 and/or Met may contribute to the development of endometrial cancers in the BDII rat.  相似文献   
87.
Tumor induction in rats by 7,12-dimethylbenz[a]anthracene (DMBA) will generate malignancies that display reproducible chromosomal abnormalities involving rat chromosome (RNO) 2. Thus, it has been reported that rat DMBA erythroleukemias display RNO2 abnormalities, which in this case were closely correlated to mutations in the Nras oncogene located in RNO2q34. Our cytogenetic analysis in a series of 17 DMBA-induced rat sarcomas showed that 11 (65%) tumors had a significant increase in RNO2 copy number. Furthermore, the incidence of point mutations in codons 12, 13 and 61 of Hras, Kras, and Nras was examined in the same set of sarcomas, and mutations were detected in three (18%) tumors, in codon 61 of Kras (CAA-->CAT) (1 of 17) and Nras (CAA-->CTA) (2 of 17). We conclude that the high frequency of RNO2 gain was in accordance with previous studies of DMBA-induced rat neoplasms, supporting the idea of a significant role of RNO2 in DMBA carcinogenesis. However, there was no clear-cut relationship between activated Nras and gain of RNO2 material, implying that mutational activation of Nras is not the causative factor underlying the gain of RNO2 copy number in rat DMBA sarcomas, in contrast to what has been suggested for DMBA-induced erythroleukemias.  相似文献   
88.
Uracil can arise in DNA by misincorporation of dUTP into nascent DNA and/or by cytosine deamination in established DNA. Based on recent findings, both pathways appear to be promoted in the methyl-deficient model of hepatocarcinogenesis. A chronic increase in the ratio dUTP:dTTP with folate/methyl deficiency can result in a futile cycle of excision and reiterative uracil misincorporation leading to premutagenic apyrimidinic (AP) sites, DNA strand breaks, DNA fragmentation and apoptotic cell death. The progressive accumulation of unmethylated cytosines with chronic methyl deficiency will increase the potential for cytosine deamination to uracil and further stress uracil mismatch repair mechanisms. Uracil is removed by a highly specific uracil-DNA glycosylase (UDG) leaving an AP site that is subsequently repaired by sequential action of AP endonuclease, 5'-phosphodiesterase, a DNA polymerase and DNA ligase. Since the DNA polymerases cannot distinguish between dUTP and dTTP, an increase in dUTP:dTTP ratio will promote uracil misincorporation during both DNA replication and repair synthesis. The misincorporation of uracil for thymine (5-methyluracil) may constitute a genetically significant form of DNA hypomethylation distinct from cytosine hypomethylation. In the present study a significant increase in the level of uracil in liver DNA as early as 3 weeks after initiation of folate/methyl deficiency was accompanied by parallel increases in DNA strand breaks, AP sites and increased levels of AP endonuclease mRNA. In addition, uracil was also detected within the p53 gene sequence using UDG PCR techniques. Increased levels of uracil in DNA implies that the capacity for uracil base excision repair is exceeded with chronic folate/methyl deficiency. It is possible that enzyme-induced extrahelical bases, AP sites and DNA strand breaks interact to negatively affect the stability of the DNA helix and stress the structural limits of permissible uracil base excision repair activity. Thus substitution of uracil for thymine induces repair- related premutagenic lesions and a novel form of DNA hypomethylation that may relate to tumor promotion in the methyl-deficient model of hepatocarcinogenesis.   相似文献   
89.
Tamoxifen is a widely used anti-estrogenic drug for chemotherapy and, more recently, for the chemoprevention of breast cancer. Despite the indisputable benefits of tamoxifen in preventing the occurrence and re-occurrence of breast cancer, the use of tamoxifen has been shown to induce non-alcoholic steatohepatitis, which is a life-threatening fatty liver disease with a risk of progression to cirrhosis and hepatocellular carcinoma. In recent years, the high-throughput microarray technology for large-scale analysis of gene expression has become a powerful tool for increasing the understanding of the molecular mechanisms of carcinogenesis and for identifying new biomarkers with diagnostic and predictive values. In the present study, we used the high-throughput microarray technology to determine the gene expression profiles in the liver during early stages of tamoxifen-induced rat hepatocarcinogenesis. Female Fisher 344 rats were fed a 420 ppm tamoxifen containing diet for 12 or 24 weeks, and gene expression profiles were determined in liver of control and tamoxifen-exposed rats. The results indicate that early stages of tamoxifen-induced liver carcinogenesis are characterized by alterations in several major cellular pathways, specifically those involved in the tamoxifen metabolism, lipid metabolism, cell cycle signaling, and apoptosis/cell proliferation control. One of the most prominent changes during early stages of tamoxifen-induced hepatocarcinogenesis is dysregulation of signaling pathways in cell cycle progression from the G(1) to S phase, evidenced by the progressive and sustained increase in expression of the Pdgfc, Calb3, Ets1, and Ccnd1 genes accompanied by the elevated level of the PI3K, p-PI3K, Akt1/2, Akt3, and cyclin B, D1, and D3 proteins. The early appearance of these alterations suggests their importance in the mechanism of neoplastic cell transformation induced by tamoxifen.  相似文献   
90.
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