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1.
To evaluate the cost effectiveness of home versus clinic blood pressure 11 patients with mild untreated hypertension were instructed in self-measurement of blood pressure with mercury manometers. The lower total cost of using home readings as well as problems of bias and blinding are discussed. Home blood pressure is a promising technique for clinical and epidemiologic research.  相似文献   
2.
The Isfahan Healthy Heart Programme (IHHP) is a five to six year comprehensive integrated community-based programme for cardiovascular diseases (CVD) prevention and control via reducing CVD risk factors and improvement of cardiovascular healthy behaviour in a target population. IHHP started late in 1999 and will be finished in 2005-2006. A primary survey was done to collect baseline data from interventional (Isfahan and Najaf-Abad) and reference (Arak) communities. In a two-stage sampling method, we randomly selected 5 to 10 percent of households from randomly selected clusters. Then individuals aged > or = 19 years were selected for the survey. This way, data from 12,600 individuals (6300 in interventional counties and 6300 in the reference county) was collected and stratified according to living area (urban vs. rural) and different age and sex groups. The samples underwent a 30-minute interview to complete validated questionnaires containing questions on demography, socioeconomic status, smoking behaviour, physical activity, nutritional habits and other behaviour regarding CVD. Blood pressure and body mass index (BMI) measurements were done and fasting blood samples were taken for two hours post load plasma glucose (2 hpp), serum (total, HDL and LDL) cholesterol and triglyceride levels. A twelve-lead electrocardiogram was recorded in all persons above 35 years of age. Community-wide surveillance of deaths, hospital discharges, myocardial infarction and stroke registry was carried out in the intervention and control areas. Four to five years of interventions based on different categories such as mass media, community partnerships, health system involvement and policy and legislation have started in the intervention area while Arak will be followed without intervention. Considering the results of the baseline surveys, (assessments needed, the objectives, existing resources and the possibility of national implementation) the interventions were planned. They were set based on specific target groups like school children, women, work-site, health personnel, high-risk persons, and community leaders were actively engaged as decision makers. A series of teams was arranged for planning and implementation of the intervention strategies. Monitoring will be done on small samples to assess the effect of different interventions in the intervention area. While four periodic surveys will be conducted on independent samples to assess health behaviours related to CVD risk factors in the intervention and reference areas, the original pre-intervention subjects aged more than 35 years will be followed in both areas to assess the individual effect of interventions and outcomes like sudden death, fatal and nonfatal MI and stroke. The whole baseline survey will be repeated on the original and an independent sample in both communities at the end of the study.  相似文献   
3.
In previous studies on patients with juvenile chronic myelogenous leukaemia (JCML), we found excessive proliferation of malignant monocyte-macrophage elements in the absence of exogenous growth factor, and impaired growth of normal haematopoietic progenitors. In the current study, six newly-diagnosed JCML patients were investigated to characterize the disease further. In co-cultures, JCML cell culture supernatant as well as patient plasma obtained at diagnosis produced a striking reduction in numbers of control marrow BFU-E, CFU-GM, CFU-Meg and CFU-GEMM colonies. Monoclonal anti-tumour necrosis factor alpha neutralizing antibodies (anti-TNF-alpha Ab) abolished these inhibitory properties. In sharp contrast, JCML supernatants exerted a marked growth-promoting effect on autologous JCML cells cultured in clonogenic assays. Anti-TNF-alpha Ab and anti-granulocyte-macrophage colony-stimulating factor neutralizing antibodies (anti-GM-CSF Ab) both reversed the stimulating effect. Recombinant GM-CSF and recombinant TNF alpha produced a profound increase in JCML colonies when tested individually and anti-GM-CSF Ab reversed the TNF-alpha effect. Expression studies of TNF-alpha and TNF-alpha receptor genes of cultured JCML cells demonstrated mRNAs for both. Further, TNF-alpha activity was assayed in a wide variety of cell culture supernatants and in normal and patients' plasma, and only the JCML specimens showed increased TNF-alpha values. Recombinant interleukin-1 alpha (IL-1 alpha) also stimulated JCML colony growth, but polyclonal anti-IL-1 neutralizing antibodies did not suppress JCML colony numbers nor did it reverse the effects of TNF-alpha or GM-CSF. The evidence indicated that the JCML monokine which inhibits normal haematopoiesis is TNF-alpha and that the endogenously-produced TNF-alpha and GM-CSF from JCML cells play an important role in the pathogenesis of the disease by acting as autocrine growth factors. IL-1 alpha also stimulates JCML cell proliferation as an accessory factor and augments the effect of GM-CSF, TNF-alpha or both.  相似文献   
4.
Malignant adenomyoepithelioma (MAME) of the breast is a rare lesion characterized by dual population of epithelial and myoepithelial cells which one or both components show malignant features. We report a case of MAME of the breast in a 46‐year‐old woman diagnosed by fine‐needle aspiration with extensive review of the literature. Classification, clinical presentation, cyto‐pathologic, and immunohistochemical features are described. This lesion showed both malignant components of epithelial and myoepithelial cells in cytology and histology. The malignancy was convincingly supported by high mitotic figures, pleomorphism, and invasion in tissue sections. This review of MAMEs showed that cyto‐histologic diagnosis is difficult and should be supported by immunohistochemical study.  相似文献   
5.
PURPOSE: To determine the contribution of pneumolysin and autolysin, two putative pneumococcal virulence proteins, to the pathogenesis of Streptococcus pneumoniae endophthalmitis. METHODS: Endophthalmitis was established in Lewis rats by intravitreal injection of pneumococcal strains at an inoculum of 10 organisms. The virulence of three closely related type 2 S. pneumoniae strains were compared: a pneumolysin-deficient derivative (PLN-A), an autolysin-deficient derivative (AL-6), and their isogenic wild-type parent (D 39). Clinical and histologic inflammation scores were compared 24 hours and 48 hours after inoculation. RESULTS: Eyes infected with PLN-A and AL-6 strains showed less anterior segment inflammation clinically at 24 hours than did eyes infected with the wild-type strain. Histologic examination at 24 hours showed significantly less corneal infiltration and vitritis and more relative preservation of retinal tissue in eyes infected with PLN-A and AL-6 strains than in eyes infected with the wild-type strain. At 48 hours, no observable differences between PLN-A and wild-type strains were present clinically or histologically. Histologically, however, the AL-6 strain caused less retinal damage than did the wild-type strain. CONCLUSIONS: Intraocular infection with pneumolysin-deficient S. pneumoniae results in less severe tissue damage in the first 24 hours of disease compared with infection with pneumolysin-producing S. pneumoniae. Autolysin-deficient S. pneumoniae shows a similar degree of attenuated virulence. Pneumolysin and autolysin may contribute to the early pathogenesis of pneumococcal endophthalmitis.  相似文献   
6.

Introduction

Oral peripheral and central giant cell granulomas are lesions with little-known etiology and pathogenesis.

Objective

The aim of this study was to compare matrix metalloproteinases-2 and osteopontin protein expression in the multinucleated giant cells and mononuclear cells of the peripheral and central giant cell granuloma lesions.

Methods

In this retrospective study, the presence of matrix metalloproteinases-2 and osteopontin in 37 cases of central giant cell granuloma and 37 cases of peripheral giant cell granuloma paraffin blocks were assessed by streptavidin-biotin immunohistochemistry. Independent sample t-test, Chi-square, Mann–Whitney tests and Spearman's rank correlation coefficient were used.

Results

The osteopontin was expressed in both multinucleated giant cells and mononuclear cells in all cases of peripheral and central giant cells granulomas. However, the matrix metalloproteinases-2 expression was positive in 86.5% of giant cells and it was positive in all of mononuclear cells in peripheral giant cells granuloma. In central giant cells granulomas, 91.8% of giant cells and all mononuclear cells were positive for matrix metalloproteinases-2 marker. Percentage and Intensity of staining were significantly higher in central than peripheral giant cells lesions, for both markers (p ? 0.05).

Conclusion

This study showed that the expression of osteopontin in giant cells supports the theory of osteolcastic nature of these cells. Also, the presence of osteopontin and matrix metalloproteinases-2 in mononuclear cells may indicate the monocyte-macrophage origin of these cells, as the differentiation of the precursors of the mononuclear stromal monocyte/macrophage to osteoclasts is possibly affected by the expression of osteolytic factors. Also, may be differences in biological behaviors of these lesions are associated with the level of osteopontin and matrix metalloproteinases-2 expression.  相似文献   
7.
Saleh-Gohari N  Helleday T 《Oncogene》2004,23(56):9136-9141
The BRCA2 tumour suppressor protein is involved in maintaining genetic stability through its role in homologous recombination (HR), where it mediates RAD51-dependent strand invasion. Here, we show that BRCA2-defective cells are not completely impaired in HR by strand invasion although the spontaneous HR rate is 10-fold lower than that in wild-type cells. Furthermore, a DNA double-strand break (DSB) triggers HR repair by strand invasion also in BRCA2-defective cells, but less efficiently. Thus, either the strand invasion pathway(s) in which BRCA2 operates is still operative in the absence of a functional BRCA2, albeit at a reduced frequency, or there is a separate pathway for strand invasion still functional in BRCA2-deficient cells. Consistent with the latter hypothesis, we show that HR events occurring in BRCA2-defective cells differ from HR events in wild-type cells. These data suggest that BRCA2-defective hamster cells are impaired in short tract gene conversion but maintain proficiency in sister chromatid exchange.  相似文献   
8.
Between 1971 and 1974, 646 evaluable patients under 20 years of age with previously untreated acute lymphocytic leukemia were treated according to Cancer and Leukemia Group B (formerly Acute Leukemia Group B) Protocol 7111. On a random basis, they received a 10-day course of 1,000 units/kg/day of L-asparaginase before, during, or after a 3-week course of vincristine and corticosteroid. A control group received vincristine and corticosteroid for 4 weeks but no asparaginase. The overall complete remission rate was 85%, which was not altered significantly by any of the induction variables. Patients who received asparaginase for 10 days subsequent to vincristine and corticosteroid had a significantly longer complete remission duration with an estimated median of 45 months, compared to 20 months for the group receiving no asparaginase and 27 months for the other 2 asparaginase regimens. The beneficial effect of asparaginase was noted, irrespective of which 1 of the 2 intensification and maintenance programs the patients received. The 5-year projection indicates a complete remission rate of 50% for those patients receiving subsequent asparaginase as compared to 41% of those induced on other regimens in this study and thus is superior to the use of only vincristine and corticosteroid.  相似文献   
9.
To evaluate the impact of Computerized Provider Order Entry (CPOE) on workplace stress and overall job performance, as perceived by medical students, housestaff, attending physicians and nurses, after CPOE implementation at Penn State—Milton S. Hershey Medical Center, an academic tertiary care facility, in 2005. Using an online survey, the authors studied attitudes towards CPOE among 862 health care professionals. The main outcome measures were job performance and perceived stress levels. Statistical analyses were conducted using the Statistical Analytical Software (SAS Inc, Carey, NC). A total of 413 respondents completed the entire survey (47.9 % response rate). Respondents in the younger age group were more familiar with the system, used it more frequently, and were more satisfied with it. Interns and residents were the most satisfied groups with the system, while attending physicians expressed the least satisfaction. Attending physicians and fellows found the system least user friendly compared with other groups, and also tended to express more stress and frustration with the system. Participants with previous CPOE experience were more familiar with the system, would use the system more frequently and were more likely to perceive the system as user friendly. User satisfaction with CPOE increases by familiarity and frequent use of the system. Improvement in system characteristics and avoidance of confusing terminology and inconsistent display of data is expected to enhance user satisfaction. Training in the use of CPOE should start early, ideally integrated into medical and nursing school curricula and form a continuous, long-term and user-specific process. This is expected to increase familiarity with the system, reducing stress and leading to improved user satisfaction and to subsequent enhanced safety and efficiency.  相似文献   
10.
A patient with acute T-lymphoblastic leukemia was found to maintain a normal hemoglobin concentration both at presentation and preterminally several months later, despite a replaced bone marrow and over 80% circulating lymphoblasts on both occasions. Cell surface marker analysis demonstrated the T-lymphoblasts both at presentation and preterminally to belong to the T-helper subpopulation. In vitro culture studies demonstrated that the patient's T-lymphoblasts, as well as conditioned medium derived from these lymphoblasts, significantly stimulated normal bone marrow erythroid colony growth (CFU-E). These findings suggest that in this patient the preservation of erythropoiesis resulted from a helper effect exerted by his T-lymphoblasts.  相似文献   
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