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991.
The in vitro activities of povidone iodine, potassium peroxymonosulfate, and dimethyldidecylammonium chloride were investigated against 379 nosocomial isolates of Staphylococcus aureus and Pseudomonas aeruginosa responsible for surgical wound infections in patients operated on between July 1995 and June 2001. Overall, the isolates were inhibited by the antiseptics at concentrations below those used routinely. In spite of increasing resistance to the various antibiotics used to treat surgical wound infections, no significant variation in the susceptibility to antiseptics was demonstrated during this 6-year study. Electronic Publication  相似文献   
992.
993.
We have measured the release of adenosine and inosine from the dorsal surface of the brainstem and from within the nucleus tractus solitarii (NTS) during the defence response evoked by hypothalamic stimulation in the anaesthetised rat. At the surface of the brainstem, only release of inosine was detected on hypothalamic defence area stimulation. This inosine signal was greatly reduced by addition of the ecto-5'-nucleotidase inhibitor α,β-methylene ADP (200 μM), suggesting that the inosine arose from adenosine that was produced in the extracellular space by the prior release of ATP. By placing a microelectrode biosensor into the NTS under stereotaxic control we have recorded release of adenosine within this nucleus. By contrast to the brainstem surface, a fast increase in adenosine, accompanied only by a much smaller change in inosine levels, was seen following stimulation of the hypothalamic defence area. The release of adenosine following hypothalamic stimulation was mainly confined to a narrow region of the NTS some 500 μm in length around the level of the obex. Interestingly the release of adenosine was depletable: when the defence reaction was evoked at short time intervals, much less adenosine was released on the second stimulus. Our novel techniques have given unprecedented real-time measurement and localisation of adenosine release in vivo and demonstrate that adenosine is released at the right time and in sufficient quantities to contribute to the cardiovascular components of the defence reaction.  相似文献   
994.
The infertility distress scale (IBS) has been designed to assess the stress perceived by andrological patients resulting from infertility. This review presents findings from different studies with a total of 769 patients. The scale consists of eight items. The stability of scores is very high even for a mean follow-up of 2 years. The scale correlates highly with an already validated measure of infertility distress. Correlations with measures of depressiveness are in the low to medium range. All in all, the psychometric results indicate that the IBS is a factor-stable, reliable and valid instrument for assessing chronic infertility distress in andrological patients. After the presentation of normative data, the usefulness of the IBS as a screening instrument for identifying highly distressed patients is discussed. Findings supporting the scale's sensitivity to change are also presented. The scale is a useful tool in clinical practice as well as in research.  相似文献   
995.
OBJECTIVE: To assess the effect of the residual stresses due to cement curing on the load transfer of cemented hip implants. DESIGN: The load transfer at the stem-cement interface of an idealized hip stem surrounded by cortical bone was investigated using a three-dimensional finite element analysis. A debonded stem-cement interface was considered to simulate a highly polished stem in contact with cement; Coulomb friction at the stem-cement interface was considered. BACKGROUND: Numerical analyses on the load transfer of cemented hip implants do not include residual stresses due to cement curing at the stem-cement interface. METHODS: The magnitude of the residual stresses was determined experimentally. In the finite element model, non-linear contact elements modelled the debonded stem-cement interface. In particular, the compressive radial residual stresses that are generated at the interface, due to the cement expansion during curing, were treated similar to a press-fit problem. RESULTS: The cement stress distributions were affected by the magnitude of the residual stresses. Failing to include residual stresses underestimated the cement stresses at the interface, mainly affecting the radial and hoop stresses. The load was transferred from the stem to the cement more uniformly along the interface once residual stresses were included. CONCLUSIONS: Because there is no chemical bond at the interface between the stem and cement, the interface resistance depends on friction thus radial residual compressive stresses developed by the cement curing play a direct role. RELEVANCE: Implant loosening of cemented hip implants is one of the major causes of late failure of the arthroplasty. The load is transferred from the stem to the bone primarily across the interfaces, consequently modelling accurately the interface is essential in predicting the load transfer.  相似文献   
996.
997.
OBJECTIVE: This study aimed to investigate the rate of occupational sensitization to horse hair in grooms and whether occupational exposure to horse hair increases respiratory and allergic symptoms and affects lung function in grooms or not. METHODS: This is a cross-sectional study. Two hundred grooms were randomly selected among 1000 grooms working in Veliefendi Hippodrome of Istanbul. One hundred and twenty-five subjects agreed to enter the study. Ninety-two workers who worked in the different parts of this hippodrome enrolled as the control group. A detailed questionnaire including respiratory and allergic symptoms was filled in, physical examination, skin prick tests and pulmonary function tests were performed. RESULTS: Sensitization to horse hair was 12.8% in grooms and 4.3% in controls. The difference was statistically significant (P = 0.0035). Asthma was found in 14.4% of the grooms and 5.4% of the controls, allergic rhinitis in 42.4% of the grooms and 18.4% of the controls, allergic conjunctivitis in 35.2% of the grooms and 15.2% of the controls, and allergic skin diseases in 32.8% of the grooms and 13% of the controls. The differences were statistically significant (P = 0.043, P = 0.0002, P = 0.001 and P = 0.0008, respectively). The means of FEV1, FEV1/FVC and FVC parameters were significantly lower in the groom group (P = 0.006, P = 0.001 and P = 0.003, respectively). In the multivariate analysis, being in the groom group and working years were found to be predictive factors for impairments of lung function (P < 0.001 and P = 0.002, respectively). CONCLUSION: Occupational exposure to horse increases the sensitization to horse hair, induces asthma and allergic symptoms and also impairs lung functions.  相似文献   
998.
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   
999.
OBJECTIVE AND DESIGN: Neutrophils may contribute to recruiting other cells to sites of inflammation by generating chemotactic signals themselves, or by stimulating other cell types to release chemoattractants such as interleukin-8 (IL-8). Recently, we demonstrated that neutrophil-derived alpha-defensins are able to increase IL-8 expression in airway epithelial cells. In addition, it has previously been reported that neutrophil elastase-induced IL-8 synthesis was insensitive to inhibition by the glucocorticoid dexamethasone. The aim of the present study was to investigate the effect of defensins on the expression of various cytokines in cultured airway epithelial cells and to examine the effect of dexamethasone on defensin-induced cytokine synthesis in these cells. METHODS: Cultures of A549 cells and primary bronchial epithelial cells (PBEC) were stimulated with defensins either alone or in the presence of dexamethasone. Supernatants were analyzed for IL-8, ENA-78, IL-6, MCP-1 and GM-CSF by ELISA. In addition, IL-8 and ENA-78 mRNA was detected by Northern blot analysis. RESULTS: Defensins increased IL-8 expression, ENA-78, MCP-1 and GM-CSF release from A549 cells, whereas in PBEC only IL-8 and IL-6 were increased. Pre-treatment with dexamethasone significantly reduced defensin-induced IL-6, IL-8 and ENA-78 synthesis in airway epithelial cells. In addition, dexamethasone also reduced the neutrophil chemotactic activity in supernatants of these cells. CONCLUSIONS: The results from the present study indicate that defensins differentially induce cytokine secretion by A549 cells and PBEC. Glucocorticoids may interfere with the defensin-induced inflammatory process by reducing defensin-induced cytokine secretion in lung epithelial cells.  相似文献   
1000.
PURPOSE: This study retrospectively evaluated the soft tissue healing after using parasagittal soft tissue incisions for surgical segmental maxillary expansion. PATIENTS AND METHODS: The records of 311 patients (224 females, 87 males), with an average age of 28.5 years (range, 12 to 62 years) who had transverse maxillary hypoplasia, were retrospectively evaluated. All patients underwent segmental maxillary osteotomies, surgical maxillary expansion greater than 5 mm, and placement of midpalatal porous block hydroxyapatite (PBHA). Parasagittal palatal soft tissue incisions were used to facilitate expansion, minimize soft tissue damage, and maintain soft tissue coverage over the PBHA implants. At postoperative follow-up visits, any signs or symptoms of complications associated with the use of the parasagittal incisions were recorded. RESULTS: Average patient follow-up was 3.4 years (range, 1.0 to 7.2 years). In 293 patients (94%), the palates healed uneventfully without complications. Eighteen patients (6%) had complications; 9 (2.9%) had infections associated with the midpalatal implants, 8 (2.6%) had oronasal communications, and 1 (0.3%) had problems associated with a palatal wire. Six patients with midpalatal implant problems required removal of the implant, 4 patients required closure of their oronasal communications, and 1 patient required removal of a palatal wire. Therefore, 11 patients (3.5%) required minor secondary surgical procedures. No teeth or alveolar bone were lost in any of the cases. CONCLUSIONS: The use of parasagittal palatal incisions appears to be a safe technique for soft tissue management during large surgical maxillary expansions associated with segmental maxillary osteotomies and midpalatal placement of PBHA implants.  相似文献   
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