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1.
OBJECTIVE: Transmission of bacterial and viral pathogens is known to occur by hand contact with fomites. Exercise equipment in public facilities may serve as such fomites. It is not known whether equipment disinfection might reduce microorganism colonization. We performed studies to address these issues. DESIGN: Observational study of bacterial and viral culture results from hand-contact surfaces of exercise equipment, pre-exercise and postexercise; prospective study of viral culture results before and after intervention with disinfection solution. SETTING: Two fitness centers in a military community. INTERVENTION: One week trial of twice-a-day equipment disinfection. MAIN OUTCOME MEASURES: Type and number of bacteria and type of viruses present on equipment before and after exercise; prevalence of viral culture positivity on equipment before and after intervention. RESULTS: Bacterial cultures of body contact surfaces on equipment revealed benign bacterial species (coagulase-negative staphylococci, diphtheroids, and so forth) but no pathogenic bacteria whether obtained pre-exercise or postexercise, or whether from aerobic versus weight training equipment. Viral cultures revealed the presence of viruses (generally rhinoviruses) on 63 of 100 (63%) hand-contact surfaces of equipment. Weight equipment was significantly more often contaminated than aerobic equipment (73% vs. 51%; P = 0.026). Disinfection of equipment did not lower the prevalence of virus isolation (48% positive before cleaning; 86% positive after cleaning). CONCLUSIONS: There is little risk of exposure to pathogenic bacteria on exercise equipment. Such equipment may commonly serve as fomites for the transmission of viruses. These data do not suggest that disinfection of exercise equipment will offer significant protective effects against virus exposure.  相似文献   
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DNA and FISH (fluorescence in situ hybridization) analysis were carried out in 12 patients with stigmata of Turner syndrome to determine whether the Supernumerary M arker C hromosome (SMC) found cytogenetically in each of these patients was derived from the Y chromosome. The presence of a Y chromosome in these patients may predispose them to develop gonadoblastoma. PCR-Southern blot analysis, followed by FISH, was used to detect the presence of Y chromosome material. The S ex determining R egion Y (SRY), T estis S pecific P rotein Y -encoded (TSPY) and Y -chromosome R NA R ecognition M otif (YRRM) genes, which map at Yp11.31, Yp11.1–11.2 and Yp11.2/Yq11.21–11.23, respectively, were selected as markers, because they span the whole Y chromosome, and more importantly, they are considered to be involved in the development of gonadoblastoma. It was shown that in 12 patients, all of whom had an SMC, the SMC of 11 was derived from the Y chromosome. Furthermore, the presence of the SRY, TSPY and YRRM gene sequences was determined and FISH analysis confirmed the Y origin of the SMCs. The methodology described in this report is a rapid, reliable and sensitive approach which may be easily applied to determine the Y origin of an SMC carried in Turner syndrome. The identification of an SMC is important for the clinical management and prognostic counseling of these patients with Turner syndrome.  相似文献   
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Aneurysmal bone cyst (ABC) is a benign locally aggressive tumor that occurs in childhood and early adulthood. Most relevant differential diagnoses are the telangiectatic osteosarcoma and the giant cell tumor. In the present case series chemotherapy following the EURAMOS or the Euro‐Ewing 99 protocol was externally applied in three patients with the misdiagnosis of ABC as malignant bone tumor. In all three cases, a significant reduction of the volume of the ABC was achieved. This is the first report about the use of neoadjuvant chemotherapy in ABC. Chemotherapy reduces the size of an ABC and leads to progressive sclerosis.  相似文献   
7.
The biochemical basis of life-history tradeoffs is a poorly studied aspect of life-history evolution. We used radiotracer and endocrine approaches to investigate the extent to which morphs of a wing-polymorphic insect differ in the biosynthesis of lipid classes important for dispersal capability vs. reproduction (ovarian growth). The flight-capable genotype of Gryllus firmus biosynthesized a greater amount of total lipid and triglyceride (main flight fuel), which was preferentially allocated to somatic tissue during early adulthood. By contrast, the flightless genotype biosynthesized a significantly greater amount of phospholipid (important in egg development), which was preferentially allocated to ovaries. Topical application of a juvenile-hormone mimic to the flight-capable morph caused it to express all aspects of lipid metabolism seen in the flightless morph. Differences in biosynthesis between morphs (i) occur coincident with 100-400% greater ovarian growth in the flightless morph, (ii) result from alterations of both de novo biosynthesis of fatty acid and downstream partitioning of fatty acids into triglyceride vs. phospholipid, and (iii) possibly result from genetically polymorphic hormonal regulators with negative pleiotropic effects on lipid biosynthesis and ovarian growth. The present study provides direct documentation of genetically based alterations of in vivo flux through pathways of intermediary metabolism leading to the differential production of end products central to the specialization of phenotypes for alternate life histories.  相似文献   
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Rodriguez JL  Peterson DJ  Muehlstedt SG  Zera RT  West MA  Bubrick MP 《Surgery》2001,130(4):539-44; discussion 544-5
BACKGROUND: Managed care and governmental policies have restructured hospital reimbursement. We examined reimbursement trends in trauma care to assess the impact of this market driven change on an urban academic health center. METHODS: Patients injured between January 1997 and December 1999 were analyzed for Injury Severity Score (ISS), length of hospital stay, hospital cost, payer, and reimbursement. RESULTS: Between 1997 and 1999, the volume of patients with an ISS less than 9 increased and length of stay decreased. In addition, overall cost, payment, and profit margin increased. Commercially insured patients accounted for this margin increase, because the margins of managed care and government insured patients experienced double-digit decreases. Patients with ISS of 9 or greater also experienced a volume increase and a reduction in length of stay; however, costs within this group increased greater than payments, thereby reducing profit margin. Whereas commercially insured patients maintained their margin, managed care and government insured patients did not (double- and triple-digit decreases). CONCLUSIONS: Managed care and current governmental policies have a negative impact on urban academic health center reimbursement. Commercial insurers subsidize not only the uninsured but also the government insured and managed care patients as well. National awareness of this issue and policy action are paramount to urban academic health centers and may also benefit commercial insurers.  相似文献   
9.
Darodipine is a new light stable dihydropyridine calcium antagonist. In isolated large conductance vessels from experimental animals, darodipine blocks the potential-dependent but not the receptor-operated calcium channel. We studied the effects of darodipine in isolated human epicardial coronary arteries and in isolated right ventricular trabecula obtained from the explanted hearts of patients undergoing cardiac transplantation. In the coronary artery, the PD'2 for calcium was 9.7 and for carbachol was 9.5. In the cardiac muscle, the PD'2 for calcium was 6.5. Using 45Ca2+, darodipine blocked uptake in presence of potassium and histamine. We conclude that darodipine is (1) a potent calcium antagonist in the isolated human coronary artery, but not in ventricular myocardium, thus showing very pronounced target tissue selectivity, and (2) in contrast to findings obtained in rabbit aorta, it inhibits contraction and 45Ca2+ uptake mediated by both the potential-dependent and receptor-operated channels in the human epicardial coronary artery.  相似文献   
10.
Comparison of bursting pressure of sutured,stapled and BAR anastomoses   总被引:5,自引:0,他引:5  
The study was undertaken to compare anastomotic bursting pressure (ABP) of colorectal canine anastomoses using three different anastomotic techniques. Biofragmentable anastomotic ring (BAR), stapled, and sutured colon anastomoses were sequentially placed in each of 48 dogs following division of the colon at three equally spaced sites. Four groups of 12 dogs were sacritficed either on day 0, 3, 7, or 28 and ABP and bursting wall tension were determined. The data revealed that BAR anastomoses have the greatest strength on the day of surgery, sutured anastomoses are the strongest on the third day and all are comparable by the 7th day. Bursting pressures for all groups by day 28 approach normal colonic bursting pressure, with any differences likely to be a reflection of variation in anastomotic fibrosis and other factors.
Résumé Cette étude a été réalisée pour comparer la pression de rupture anastomotique de l'anastomose colo-rectale chez le chien utilisant trois différentes techniques d'anastomose. Anneau anastomotique biofragmentable (AAB), pince à suture automatique et suture manuelle ont été placées de façon séquentielle chez chacun des 48 chiens après section du colon en trois endroits placés à égale distance. 4 groupes de 12 chiens ont été sacrifiés au jour 0, 3, 7, 28, la pression de rupture anastomotique et la tension pariétale de rupture ont été étudiées. Les résultats révèlent que les anneaux anastomotiques biofragmentables ont une plus grande force le jour de l'intervention, les anastomoses manuelles sont plus solides au troisième jour et toutes sont comparables au septième jour. La pression de rupture pour tous les groupes au 28ème jour approche la pression colique normale de rupture avec quelques différences qui reflêtent probablement des variations de la fibrose anastomotique ou d'autres facteurs.


Supported in part by a grant ftom the Davis and Geck Medical Division, Division of American Cyanamid Company, Wayne, New Jersey

Presented at the 90th Annual Meeting of the American Society of Colon and Rectal Surgeons, Boston, Massachusetts, May 12–17, 1991  相似文献   
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