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91.
Hochwald SN Lind DS Malaty J Copeland EM Moldawer LL MacKay SL 《The American surgeon》2003,69(1):15-23
92.
93.
Feldman KA Stiles-Enos D Julian K Matyas BT Telford SR Chu MC Petersen LR Hayes EB 《Emerging infectious diseases》2003,9(3):350-354
We conducted a serosurvey of landscapers to determine if they were at increased risk for exposure to Francisella tularensis and to determine risk factors for infection. In Martha's Vineyard, Massachusetts, landscapers (n=132) were tested for anti-F. tularensis antibody and completed a questionnaire. For comparison, serum samples from three groups of nonlandscaper Martha's Vineyard residents (n=103, 99, and 108) were tested. Twelve landscapers (9.1%) were seropositive, compared with one person total from the comparison groups (prevalence ratio 9.0; 95% confidence interval 1.2 to 68.1; p=0.02). Of landscapers who used a power blower, 15% were seropositive, compared to 2% who did not use a power blower (prevalence ratio 9.2; 95% confidence interval 1.2 to 69.0; p=0.02). Seropositive landscapers worked more hours per week mowing and weed-whacking and mowed more lawns per week than their seronegative counterparts. Health-care workers in tularemia-endemic areas should consider tularemia as a diagnosis for landscapers with a febrile illness. 相似文献
94.
Brantley-Finley C Lyle CS Du L Goodwin ME Hall T Szwedo D Kaushal GP Chambers TC 《Biochemical pharmacology》2003,66(3):459-469
Assessment of specific apoptosis and survival pathways implicated in anticancer drug action is important for understanding drug mechanisms and modes of resistance in order to improve the benefits of chemotherapy. In order to better examine the role of mitogen-activated protein kinases, including JNK and ERK, as well as the tumor suppressor p53, in the response of tumor cells to chemotherapy, we compared the effects on these pathways of three structurally and functionally distinct antitumor agents. Drug concentrations equal to 50 times the concentration required to reduce cell proliferation by 50% were used. Vinblastine, doxorubicin, or etoposide (VP-16) induced apoptotic cell death in KB-3 carcinoma cells, with similar kinetic profiles of PARP cleavage, caspase 3 activation, and mitochondrial cytochrome c release. All three drugs strongly activated JNK, but only vinblastine induced c-Jun phosphorylation and AP-1 activation. Inhibition of JNK by SP600125 protected cells from drug-induced cytotoxicity. Vinblastine caused inactivation of ERK whereas ERK was unaffected in cells exposed to doxorubicin or VP-16. Inhibition of ERK signaling by the MEK inhibitor, U0126, potentiated the cytotoxic effects of vinblastine and doxorubicin, but not that of VP-16. Vinblastine induced p53 downregulation, and chemical inhibition of p53 potentiated vinblastine-induced cell death, suggesting a protective effect of p53. In contrast, doxorubicin and VP-16 induced p53, and inhibition of p53 decreased drug-induced cell death, suggesting a pro-apoptotic role for p53. These results highlight the differential roles played by several key signal transduction pathways in the mechanisms of action of key antitumor agents, and suggest ways to specifically potentiate their effects in a context-dependent manner. In addition, the novel finding that JNK activation can occur without c-Jun phosphorylation or AP-1 activation has important implications for our understanding of JNK function. 相似文献
95.
Relation of left ventricular hypertrophy to inflammation and albuminuria in adults with type 2 diabetes: the strong heart study 总被引:5,自引:0,他引:5
Palmieri V Tracy RP Roman MJ Liu JE Best LG Bella JN Robbins DC Howard BV Devereux RB;Strong Heart Study 《Diabetes care》2003,26(10):2764-2769
OBJECTIVE: To evaluate in adults with type 2 diabetes the extent to which the relation of left ventricular hypertrophy (LVH) to markers of systemic inflammation (fibrinogen and high-sensitivity C-reactive protein [hsCRP]) are affected by microangiopathy. RESEARCH DESIGN AND METHODS: We selected adults with type 2 diabetes using American Diabetes Association criteria from a population-based cohort, excluding those with medical history or electrocardiographic evidence of coronary heart disease or dialysis-dependent renal failure. LVH was assessed by echocardiogram. RESULTS: Of the 1299 eligible participants, 384 (29.6%) had LVH, which was associated with higher BMI, hsCRP, fibrinogen, and albuminuria in univariate analyses. After controlling for significant confounders, fibrinogen and albuminuria were higher in the presence of LVH (both P < 0.01), whereas hsCRP was not (P = 0.2), mostly because of the confounding effect of BMI. Adjustment for albuminuria abolished the relation of LVH to higher fibrinogen (P = 0.2). However, fibrinogen was significantly higher in participants with LVH among those without pathologic levels of albuminuria (<30 mg/g creatinuria), but not independent of BMI. Although hsCRP and fibrinogen were moderately correlated, fibrinogen, but not CRP, showed a significant relation with albuminuria. CONCLUSIONS: In adults with type 2 diabetes, echocardiographic LVH is associated with susceptibility to atherothrombosis and increased albuminuria, which is a marker of microangiopathy and endothelial dysfunction that appears in turn to be a relevant pathogenetic link between LVH and inflammation. However, in the absence of significant microalbuminuria, elevated BMI is a relevant pathogenetic factor in the relation of LVH to increased levels of markers of inflammation, potentially preceding development of significant albuminuria. In the presence of microangiopathy, we found that the atherothrombotic risk profile associated with LVH was independent of BMI and possibly reflected the association of LVH with a higher degree of endothelial dysfunction. 相似文献
96.
Linear scleroderma is an unusual disorder characterized by linear streaks of fibrotic skin involvement, which can lead to severe limb deformities and contractures. The authors present a case of severe wrist contracture in a child with linear scleroderma treated by release of the contracture with coverage of the exposed carpus with an abductor digiti minimi flap and skin graft. Reports of successful treatment of extremity deformities are rare. At 1 year this correction appears to have been successful. 相似文献
97.
N Deborah Friedman Ann L Bull Philip L Russo Lyle Gurrin Michael Richards 《Infection control and hospital epidemiology》2007,28(1):55-59
BACKGROUND: The Victorian Hospital Acquired Infection Surveillance System (VICNISS) hospital-acquired infection surveillance system was established in 2002 in Victoria, Australia, and collates surgical site infection (SSI) surveillance data from public hospitals in Australia. OBJECTIVE: To evaluate the association between the US National Nosocomial Infections Surveillance (NNIS) system's risk index and SSI rates for 7 surgical procedures. METHODS: SSI surveillance was performed with NNIS definitions and methods for surgical procedures performed between November 2002 and September 2004. Correlations were assessed using the Goodman-Kruskal gamma statistic. RESULTS: Data were submitted for the following numbers of procedures: appendectomy, 545; coronary artery bypass graft (CABG), 4,632; cholecystectomy, 1,001; colon surgery, 623; cesarean section, 4,857; hip arthroplasty, 3,825; and knee arthroplasty, 2,416. NNIS risk index and increasing SSI rate were moderately well correlated for appendectomy ( gamma =0.55), colon surgery ( gamma =0.48), and cesarean section ( gamma =0.42). A fairly positive correlation was found for cholecystectomy ( gamma =0.17), hip arthroplasty ( gamma =0.2), and knee arthroplasty ( gamma =0.16). However, for CABG surgery, a poor association was found ( gamma =0.02). CONCLUSIONS: The NNIS risk index was positively correlated with an increasing SSI rate for all 7 procedures; the strongest correlation was found for appendectomy, cesarean section, and colon surgery, and the poorest correlation was found for CABG surgery. We believe that risk stratification with the NNIS risk index is appropriate for comparison of data for most procedures and superior to use of no risk adjustment. However, for some procedures, particularly CABG, further studies of alternative risk indexes are needed to better stratify patients. 相似文献
98.
Mohammad Moad Deepali Pal Anastasia C. Hepburn Stuart C. Williamson Laura Wilson Majlinda Lako Lyle Armstrong Simon W. Hayward Omar E. Franco Justin M. Cates Sarah E. Fordham Stefan Przyborski Jane Carr-Wilkinson Craig N. Robson Rakesh Heer 《European urology》2013
Background
Primary culture and animal and cell-line models of prostate and bladder development have limitations in describing human biology, and novel strategies that describe the full spectrum of differentiation from foetal through to ageing tissue are required. Recent advances in biology demonstrate that direct reprogramming of somatic cells into pluripotent embryonic stem cell (ESC)-like cells is possible. These cells, termed induced pluripotent stem cells (iPSCs), could theoretically generate adult prostate and bladder tissue, providing an alternative strategy to study differentiation.Objective
To generate human iPSCs derived from normal, ageing, human prostate (Pro-iPSC), and urinary tract (UT-iPSC) tissue and to assess their capacity for lineage-directed differentiation.Design, setting, and participants
Prostate and urinary tract stroma were transduced with POU class 5 homeobox 1 (POU5F1; formerly OCT4), SRY (sex determining region Y)-box 2 (SOX2), Kruppel-like factor 4 (gut) (KLF4), and v-myc myelocytomatosis viral oncogene homolog (avian) (MYC, formerly C-MYC) genes to generate iPSCs.Outcome measurements and statistical analysis
The potential for differentiation into prostate and bladder lineages was compared with classical skin-derived iPSCs. The student t test was used.Results and limitations
Successful reprogramming of prostate tissue into Pro-iPSCs and bladder and ureter into UT-iPSCs was demonstrated by characteristic ESC morphology, marker expression, and functional pluripotency in generating all three germ-layer lineages. In contrast to conventional skin-derived iPSCs, Pro-iPSCs showed a vastly increased ability to generate prostate epithelial-specific differentiation, as characterised by androgen receptor and prostate-specific antigen induction. Similarly, UT-iPSCs were shown to be more efficient than skin-derived iPSCs in undergoing bladder differentiation as demonstrated by expression of urothelial-specific markers: uroplakins, claudins, and cytokeratin; and stromal smooth muscle markers: α-smooth-muscle actin, calponin, and desmin. These disparities are likely to represent epigenetic differences between individual iPSC lines and highlight the importance of organ-specific iPSCs for tissue-specific studies.Conclusions
IPSCs provide an exciting new model to characterise mechanisms regulating prostate and bladder differentiation and to develop novel approaches to disease modelling. Regeneration of bladder cells also provides an exceptional opportunity for translational tissue engineering. 相似文献99.
Jingfei Ma Sanjay K Singh Ashok J Kumar Norman E Leeds Lyle D Broemeling 《Magnetic resonance in medicine》2002,48(6):1021-1027
In order to satisfy the Carr-Purcell-Meiboom-Gill (CPMG) condition, echo shift as dictated in fast-spin-echo (FSE)-based Dixon imaging was previously achieved by applying a time shift to the readout gradient and the data acquisition window. Accordingly, interecho spacing is increased, which entails increased image blurring and, in multislice imaging, a significant reduction in the slice coverage for a given imaging time. In this work, a new method is developed by which the echo shift is induced by "sandwiching" in time the readout gradient with a pair of small gradients of equal area and of opposite polarity. While data with non-zero phase shifts between water and fat signals are collected as fractional echoes, no increase in echo spacing is necessary with the modified acquisition strategy, and increased time efficiency is therefore achieved. In order to generate separate water-only and fat-only images in data processing, a set of low-resolution images are first reconstructed from the central symmetric portion (either 128 x 128 or 64 x 64) of the acquired multipoint Dixon data. High-resolution images using all the acquired data, including some partial Fourier-reconstructed images, are then phase demodulated using the phase errors determined from the low-resolution images. The feasibility of the technique is demonstrated using a water and fat phantom as well as in clinical patient imaging. 相似文献
100.
Age at onset and persistence of eczema are related to subsequent risk of asthma and hay fever from birth to 18 years of age 下载免费PDF全文