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991.
OBJECTIVE AND DESIGN: Bacterial products as well as the host airway inflammatory responses contribute to the pathogenesis of Pseudomonas infections. We sought to determine if Pseudomonas elastase (PE) induces mitogen-activated protein (MAP) kinase activity in association with interleukin-8 (IL-8) production by alveolar epithelial cells. METHODS: We utilized Western blot analysis to detect phosphorylation of signaling intermediates and ELISA was used to measure IL-8 production. RESULTS: We found that PE induces phosphorylation of the extracellular signal-regulated (ERK1/2) proteins of the MAPK pathway in A549 epithelial cells. Similar results were obtained using primary cultures of rabbit alveolar type II epithelial cells. PE also enhanced IL-8 production, which was abolished in the presence of the ERK activation inhibitor U0126. CONCLUSIONS: We conclude that PE activates the ERK1/2 arm of the MAPK pathway and that activation of this pathway results in enhanced IL-8 production. The results demonstrate that PE may augment pulmonary inflammation via cellular signaling that regulates expression of IL-8.  相似文献   
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Maya families from Guatemala migrated to the United States in record numbers from the late 1970s to the early 1990s. Births to Maya immigrant women have created a sizable number of Maya American children. The height and sitting height of 5 to 12 years children (n = 431) were measured in 1999 and 2000. Leg length was estimated and the sitting height ratio was calculated. These data were compared with a sample of Maya children living in Guatemala measured in 1998 (n = 1,347). Maya American children are currently 11.54 cm taller and 6.83 cm longer‐legged, on average, than Maya children living in Guatemala. Consequently, the Maya Americans have a significantly lower average sitting height ratio (i.e., relatively longer legs in proportion to length of the head and trunk) than do the Maya in Guatemala. These results add support to the hypothesis that both the height and body proportions of human populations are sensitive indicators of the quality of the environment for growth. Am. J. Hum. Biol. 14:753–761, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
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This double-masked, placebo-controlled study was undertaken to determine the efficacy and safety of oral clodronate in the prevention of bone loss in early postmenopausal women with vertebral osteopenia. Altogether 610 women with a mean age of 53 years were recruited for the study. They were 1–5 years postmenopausal and their lumbar spine bone mineral density (BMD) was at least 1 standard deviation below the mean of premenopausal women (T-score ≤−1). The subjects were randomized into five study groups to receive either placebo, clodronate 65 mg, 400 mg or 800 mg daily, or intermittent clodronate in 3 month cycles with 400 mg daily for 15 days followed with no treatment for 75 days for 3 years. One hundred and eighty-seven of 509 women who completed the primary study continued in the extension study of 2 years in which previous placebo users were switched to clodronate 800 mg daily, while previous users of 400 mg or 800 mg of clodronate used either placebo or 800 mg of clodronate daily. In the primary study clodronate was administered in the evening, and in the extension 1 h before breakfast on an empty stomach. In the primary study mean changes in lumbar spine BMD were −3.4% in the placebo group and +0.4% in 800 mg clodronate group [difference between groups at 3 years 3.8% (95% CI 2.7% to 4.9%, p<0.0001)], and in the trochanter area BMD −1.1% in the placebo group, and + 0.4% in the 800 mg clodronate group [difference between groups at 3 years 1.5% (95% CI 0.05% to 2.9%)]. During the extension study mean changes in lumbar spine BMD were +1.5% in the clodronate group and −0.2 % in the placebo group [difference between groups 1.7% (CI 0.4% to 3.0%, p = 0.010)] and in trochanter BMD were +2.5% in the clodronate group and no change in the placebo group [difference between groups 2.1% (CI 0.3% to 3.9%, p = 0.007)]. No statistically significant differences between the placebo and 800 mg clodronate groups were found in the femoral neck BMD. In the primary study the urinary excretion of type I collagen aminoterminal telopeptide (NTX) decreased by 44% (p<0.0001 compared with placebo) and that of deoxypyridinoline by 18% (p<0.0001) in the clodronate 800 mg group. In the extension study urinary NTX decreased by 51% (p<0.0001) in those who were switched to 800 mg of clodronate and increased by 67% (p<0.0001) in those who stopped using that dose. There was no difference in the frequency of gastrointestinal complaints between clodronate- and placebo-treated patients in the primary study, but they were more common among women who received clodronate in the extension phase. Clodronate in daily doses of 400–800 mg caused a slight elevation of aminotransferase levels, usually within the reference range. In bone biopsies no defect in mineralization was found. In conclusion, clodronate in a daily dose of 800 mg prevents early postmenopausal bone loss at the sites of the skeleton in which cancellous bone predominates. It effectively reduces bone resorption and bone turnover rate. Antifracture efficacy of clodronate remains to be established by prospective, placebo-controlled trials. Received: 4 March 2002 / Accepted: 9 July 2002  相似文献   
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Cancer Chemotherapy and Pharmacology - Addition of solid doxorubicin or solutions to pre-formed liposomes proved to be the optimal method for incorporating the drug into liposomes whilst...  相似文献   
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Summary In cases where a reconstruction of defects in the larynx, oral cavity, the pharynx or in the ear region has been performed using skin flaps, a temporary fistula is formed at the point of entry.This fistula can be closed later after the flap has taken and the flap pedicle dissected.We would like to demonstrate with some examples that with the use of deepithelisation it is possible to achieve a primary wound closure. This way no temporary fistula results and additional surgery is avoided in many cases.Furthermore flap deepithelisation offers a way to bring good vascularised tissue under the skin and cover subcutaneous defects, for example those after radiotherapy.

Die Veröffentlichung des Manuskripts soll in Laryngol Rhinol Otol (Stuttg) erfolgen  相似文献   
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A total of 106 pairs of identical twins, of whom 56 were concordant and 50 discordant for insulin-dependent diabetes, were typed for HLA-DR. In both the concordant and discordant groups there was a high prevalence of the antigens DR3 and DR4, a low prevalence of DR5 and DR7, and a virtual absence of DR2. The heterozygous phenotype DR3,DR4 was more prevalent in concordant than discordant pairs. This was therefore the first demonstration of a genetic difference between concordant and discordant identical twin pairs. These findings suggest that possession of both DR3 and DR4 antigens confers a greater genetic predisposition to insulin-dependent diabetes than does the possession of either antigen alone.  相似文献   
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