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71.
Background : The medical literature has described the prevalence of latex allergy in the spina bifida population and its implications for surgical intervention. We report three cases of severe and unexpected intra-operative anaphylaxis secondary to latex exposure in non-spina bifida patients. Methods : A retrospective review of case notes identified three non-spina bifida patients who suffered intra-operative anaphylaxis due to latex allergy. Personal and telephone interview and patient chart review was performed to detail a past history of multiple latex exposure, atopy, the anaphylaxis event and the postoperative outcome. Results : Three non-spina bifida patients are described. One suffered a cardiopulmonary arrest, the remaining two patients had severe vascular hypotension and airway resistance that was only relieved after administration of vasoconstrictors and bronchodilators. Postoperatively, all three tested strongly positive to latex allergen testing. Each patient had a history of multiple surgical latex exposure and specific allergies or allergic-type symptoms pre-operatively. Conclusion : We believe that the predictors of a severe allergic reaction to latex with surgical exposure in non-spina bifida patients may be similar to those predictors known in the spina bifida population. Identification of such at-risk patients will reduce the risk of significant intra-operative morbidity and possible mortality by the introduction of a latex-free operating environment.  相似文献   
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Young rats (aged 22–24 days) and adult rats (aged 40–42 days) were studied during hydropenia (HP) and during volume expansion (VE) in order to clarify the role of the proximal tubule of the immature kidney in the blunted natriuretic response seen in young mammals during VE. The position of the last accessible site for micropuncture of the proximal tubular segment was determined. The disadvantages of using lissamine green as a marker of different tubular segments were investigated. Tubular function was ascertained by micropuncture of superficial proximal nephrons. Measurements of tubular length were made from latex casts of the proximal tubule. No side-effects of lissamine green were detected, when small quantities were used (20–30 μl) and at least 20 min elapsed between the infusions of the dye and tubular samplings. The last accessible proximal tubule available for micropunction was found to be similarly located in young and adult rats. Fractional reabsorption during HP remained constant during development. An equivalent degree of VE induced an increase in tubular load in both age groups, but it was more marked among younger rats. Absolute proximal reabsorption in both young and old rats in HP paralleled that of the tubular load. Fractional reabsorption, however, decreased slightly during VE but to the same extent in both age groups. This indicates a great flexibility in the immature proximal tubule under various tubular loads although it had been thought that this part of the nephron was in the later stages of development. The results imply that the proximal tubule does not create the blunted sodium response in the immature kidney during VE.  相似文献   
74.
BACKGROUND: Natural rubber latex, mainly contained in disposable medical gloves, is an important cause of occupational allergy in health care workers. Management of latex allergy includes education, reduction of cutaneous or mucosal contact with rubber products and minimization of exposure to latex allergens in the work environment. METHODS: This paper reports a case study dealing with the latex allergy health problem of an operating theatre nurse. The examination was required because of a recent onset rhino-conjunctivitis crisis and asthma during usual working activities. The case was investigated and a solution provided according to the evidence-based medicine (EBM) paradigm using the PICO model. RESULTS: The literature search was conducted using Medline and the Cochrane Library. Twenty-one papers were considered to offer appropriate solutions. Two main types of interventions were suggested: (i) changing the work setting, (ii) limiting the work activities. The evidence obtained was discussed with the nurse, who was considered unfit to continue her work in the operating theatre where her colleagues used latex gloves. The resident proposed that she could relocate to a work environment where only non-latex gloves were used and latex medical devices were not present. CONCLUSION: The case study shows that, as for other clinicians, the occupational physician can use the EBM paradigm according to the PICO model as a tool for providing appropriate solutions for the individual worker.  相似文献   
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Introduction In spite of new surgical techniques and recently developed antibiotics, there is no satisfactory solution for the treatment of chronic posttraumatic osteomyelitis. The introduction of local antibiotic treatment with gentamicin-PMMA beads according to Klemm has provided new stimuli for the treatment of chronic osteomyelitis. With the development of collagen as an absorbable carrier substance, the disadvantages of the rigid carrier system became evident. Due to the varying surgical techniques and different forms of adjuvant therapy, it is difficult to assess therapeutic methods and compare different studies. Therefore, it seemed appropriate to study the effect of local treatment with different antibiotic carriers in the setting of an animal study.Materials and methods The proven rat model for Staphylococcus aureus-induced osteomyelitis was used to compare the results of monotherapy with cefazolin, gentamicin-PMMA beads, or gentamicin-containing collagen sponge with the combination of local and systemic antibiotic treatment.Results Single-agent therapy with parenterally administered cefazolin reduced the CFU from 3.7×106 to 2.9×104 g-1 of tibial bone. The effect on osteomyelitis was more pronounced with the local application of antibiotics. The best results were achieved with the gentamicin-containing collagen sponge which reduced the bacterial colony count to 1.4×102 CFU/g compared with 9.8×102 CFU/g achieved with gentamicin-PMMA beads. The effect was most marked using a 4-week combination therapy with local application of the gentamicin-containing collagen sponge and systemic administration of cefazolin. In 9 of 11 animals, no bacteria could be detected in the bone.Conclusion Each of the treatment modalities resulted in a significant therapeutic effect. Due to its ability to quickly release large amounts of gentamicin, the flexible gentamicin-containing collagen sponge proved to be superior to the rigid PMMA system. Although the gentamicin-containing collagen sponge provided high antibiotic concentration at the site of implantation, an additive effect was attained when combined with systemic antibiotic treatment.  相似文献   
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Summary: The inner structure of polyurethane latex particles has been studied in situ using small‐angle X‐ray scattering (SAXS). From contrast variation SAXS measurements evidence could be given that the dispersed particles are semi‐crystalline. The semi‐crystalline structure gives a strong contribution to the measured intensities in an intermediate range of scattering vectors. This contribution, which is independent of the adjusted contrast, could be separated and the long period of the lamellar structure could thus be determined quantitatively to 11 nm. In addition, it was found that the particles exhibit a core‐shell structure which arises from electron‐rich acid groups that are preferentially located at the particle surface.

Transmission electron microscopy (TEM) picture of the PUR particles.  相似文献   

80.
BACKGROUND: Although public health programs invest heavily in the male latex condom, its efficacy in preventing pregnancy and sexually transmitted disease has been based primarily on in vitro and retrospective studies. METHODS: We combine the results from two randomized, controlled contraceptive efficacy trials that used commercial latex condoms brands (Ramses Sensitol, LifeStyles, Trojan-Enz) in the control arms. Combining data from the two studies, we obtained longitudinal data covering 3526 menstrual cycles contributed by approximately 800 couples who used latex condoms exclusively for up to six menstrual cycles. Both trials also collected 3715 detailed breakage and slippage reports from the first five study condom uses. The second trial also tested 243 postcoital vaginal samples collected after the first study condom use for the presence of prostate-specific antigen (PSA) and spermatazoa. RESULTS: The combined clinical breakage rate for the first five condom uses was 0.4% for the three latex brands and the combined clinical slippage rate was 1.1%. The combined six-cycle typical-use pregnancy rate for the latex condoms was 7.0% (95% confidence interval 5.0-9.0). The combined six-cycle consistent-use pregnancy rate was 1.0% (95% confidence interval 0.0-2.1). PSA was detected in only 1.2% of postcoital vaginal samples collected after the first use of an intact study condom. There were no differences in performance or efficacy among the three latex brands tested. CONCLUSIONS: The male latex condoms rarely broke or slipped off during intercourse and provided high contraceptive efficacy, especially when used consistently. Risk of semen leakage from intact condoms was very low.  相似文献   
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