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91.
Merchant JA Naleway AL Svendsen ER Kelly KM Burmeister LF Stromquist AM Taylor CD Thorne PS Reynolds SJ Sanderson WT Chrischilles EA 《Environmental health perspectives》2005,113(3):350-356
Epidemiologic studies of farm children are of international interest because farm children are less often atopic, have less allergic disease, and often have less asthma than do nonfarm children--findings consistent with the hygiene hypothesis. We studied a cohort of rural Iowa children to determine the association between farm and other environmental risk factors with four asthma outcomes: doctor-diagnosed asthma, doctor-diagnosed asthma/medication for wheeze, current wheeze, and cough with exercise. Doctor-diagnosed asthma prevalence was 12%, but at least one of these four health outcomes was found in more than a third of the cohort. Multivariable models of the four health outcomes found independent associations between male sex (three asthma outcomes), age (three asthma outcomes), a personal history of allergies (four asthma outcomes), family history of allergic disease (two asthma outcomes), premature birth (one asthma outcome), early respiratory infection (three asthma outcomes), high-risk birth (two asthma outcomes), and farm exposure to raising swine and adding antibiotics to feed (two asthma outcomes). The high prevalence of rural childhood asthma and asthma symptoms underscores the need for asthma screening programs and improved asthma diagnosis and treatment. The high prevalence of asthma health outcomes among farm children living on farms that raise swine (44.1%, p = 0.01) and raise swine and add antibiotics to feed (55.8%, p = 0.013), despite lower rates of atopy and personal histories of allergy, suggests the need for awareness and prevention measures and more population-based studies to further assess environmental and genetic determinants of asthma among farm children. 相似文献
92.
Zogakis TG Wetherille RE Christensen RD Ose KJ Friedman JD Colbert M Svendsen CA Sanan OK Tuttle TM 《Annals of surgical oncology》2005,12(2):167-172
Background Preoperative parenchymal or peritumoral (PT) injection of 99mTc-labeled sulfur colloid (TcSC) is the standard method for sentinel lymph node (SLN) identification in patients with breast cancer. Limitations of this method include variable identification rates, slow transit times, and painful injections. We hypothesize that TcSC will travel to the SLN within minutes after injection into the subareolar (SA) lymphatics, thus making an intraoperative injection technique feasible.Methods One hundred twenty-two women with invasive breast cancer were enrolled onto this prospective study. Immediately after the induction of general anesthesia, patients were injected with 1 to 2 mCi of filtered TcSC in the SA location. Then, 5 mL of 1% isosulfan blue dye was injected into the PT location. The SLN or SLNs were identified as radioactive, blue, or both and removed for pathologic evaluation.Results The mean patient age was 56 years. The mean tumor size was 1.5 cm. In 86.1% of patients, a transcutaneous axillary hot spot was identified by handheld gamma probe. The mean time from TcSC injection to axillary incision was 17.6 minutes. At least one SLN was identified in 99.2% of patients. The mean number of SLNs identified per patient was 1.83. The mean count of radioactive SLNs was 2715 cps. In 97.2% of patients, blue SLNs were also radioactive.Conclusions TcSC injected into the SA lymphatics rapidly drains to the SLN. The radioactive SLN is easily and quickly identified after an intraoperative SA TcSC injection. The simplicity of this method eliminates the inherent problems associated with standard PT injection. 相似文献
93.
We report on the evolution in concept and techniques that allowed us to improve the treatment of spigelian hernia, operable in day surgery in 90% of cases and through a preperitoneal and recently a preperitoneal and subfascial prosthetic repair (PHS). Background data. We propose an innovative use of the PHS mesh for spigelian hernia repair. With this new implementation, we confront the standard surgical technique and its postoperative period. Methods. From January 1992 to March 2004, we performed 2,500 hernia surgical operations, including 32 spigelian hernia repairs (1.3% of total case series). The first surgical approach used for 20 of these 32 patients (62.5% of total spigelian hernias), all electively operated on, was a classical preperitoneal repair (Wantz), performed when possible by size of defect and weight (Body Mass Index) of the patient, under local anesthesia and on a day-surgery basis. Our new modified technique takes place through the insertion of a PHS large-type mesh, whose bottom underlay portion lies flat in the preperitoneal space with the connector obliterating the hernial orifice and with the overlay portion lying on the internal oblique muscle, covered by the aponeurosis of the external oblique muscle. Results. Our modification to the classical technique consisted only in the application of a product, such as the PHS, in a hernia defect, which presented with an orifice of the size of the connector and, therefore, was easily repairable with the use of the PHS device. This approach is easier than the preperitoneal approach, its always suitable for local anaesthesia, and it gives a more comfortable postoperative period. The surgical approach may be performed completely in day surgery. Conclusions. We believe that spigelian hernia surgical repair should always be performed by means of a preperitoneal prosthesis under local anaesthesia when the patients clinical and physical conditions allow for it, always in day surgery, and using the PHS mesh when the hernia defect size fits with the connector diameter. This last possibility seems to be easier and more comfortable for the patient in the postoperative period. 相似文献
94.
Schmidt B Rasmussen LH Svendsen GW Ingerslev F Hansen HC 《Environmental toxicology and chemistry / SETAC》2005,24(11):2751-2756
Ptaquiloside (PTA) is a natural toxin produced by bracken (Pteridium aquilinum [L.] Kuhn). Assessment of PTA toxicity is needed because PTA deposited from bracken to soil may leach to surface and groundwater. Inhibition of soil respiration and genotoxic activity of PTA was determined by a soil microbial carbon transformation test and an umu test, respectively. In the carbon transformation test, sandy loam soil was incubated at five different initial concentrations of PTA for a period of 28 d, after which glucose was added and respiration measured for 12 consecutive hours. The tests were performed at 20 degrees C and soil moisture content of approximately 15%. For soil material sampled in the autumn, initial PTA concentrations ranging from 0.008 to 40.6 microg PTA/g dry soil were tested. From fitting of data by a sigmoidal function, a 10% effect dose (ED10) was estimated to 13 microg PTA/ g dry soil, with an upper 95% confidence limit of 43 microg PTA/g dry soil and a 95% lower confidence limit of -infinity microg PTA/g dry soil. For soil material sampled in late winter, initial PTA concentrations ranging from 1.56 to 212 microg PTA/g dry soil were tested, resulting in an ED10 value of 55 microg PTA/g dry soil, with an upper 95% confidence limit of 70 microg PTA/g dry soil and a 95% lower confidence limit of 40 microg PTA/g dry soil. The genotoxic activity of PTA was determined using the umu test without and with metabolic activation (addition of S9 rat liver homogenate). In tests with addition of S9, the induction ratio exceeded the critical ratio of 1.5 at a PTA concentration of 46 +/- 16 microg/ml and, in tests without S9, the critical ratio was exceeded at a PTA concentration of 279 +/- 22 microg/ml. The genotoxicity of PTA is comparable to that of quercetin, another bracken constituent. The toxicity of PTA toward microorganisms prolongs the persistence of PTA in terrestrial environments, increasing the risk of PTA leaching to drainage and groundwater. 相似文献
95.
96.
The quantity of the remaining unreacted methacrylate groups in polymerized composite materials has been determined. Six proprietary composites were investigated by infrared multiple internal reflection spectroscopy. Infrared reflectance measurements were made before polymerization and repeated after the composites were subjected to polymerization at 37 degrees C for 24 hours. The quantities of remaining unreacted methacrylate groups were determined and the data expressed as percentages of the total amount of methacrylate groups in the unpolymerized materials. The specimens were specially prepared to ensure that the surface properties simulated the bulk properties of the polymerized composites. The quantities of remaining methacrylate groups in the six composites determined by this surface measuring technique ranged from 25 to 48%. The results demonstrate that commercially available composite materials exhibit different degrees of conversion 24 hours after the start of polymerization. These differences can be correlated to the different monomer compositions of the composite restorative resins. 相似文献
97.
98.
Influence of injectable anaesthetic combinations on blood gas tensions and acid-base status in laboratory rats 总被引:1,自引:0,他引:1
Outbred Mol:SPRD rats were maintained in surgical anaesthesia for two hours by using five different drug combinations: 1) pentobarbitone, 2) ketamine + diazepam, 3) ketamine + pentobarbitone, 4) atropine + diazepam + fentanyl + fluanisone, 5) atropine + etorphine + acepromazine. Respiratory rate, arterial O2 and CO2 tensions, arterial pH, base excess, mean arterial blood pressure and heart rate were recorded at set intervals from 30 to 120 min. from the initiation of anaesthesia. Atropine + diazepam + fentanyl + fluanisone caused no disturbance of acid-base balance, whereas the other drug combinations induced moderate to severe acidosis. Arterial blood pressure was reduced by all methods. Pentobarbitone and regimens including ketamine reduced heart rate, whereas combinations with etorphine and fentanyl caused a rise in heart rate. 相似文献
99.
Background: Shunt failure is by far the most frequent problem in children with shunts, and most of them will experience this condition at some point in their lives. In order to identify causes of shunt failure, and to compare multi-component and one-piece shunt systems, we analyzed retrospectively all pediatric shunt procedures in our Department during an 11-year period. The study does not deal with shunt infections. Methods: We reviewed the records of all pediatric shunting procedures between January 1986 and December 1996. Results: The study included 161 children operated for hydrocephalus with a total of 431 procedures. The procedures included 124 (29%) primary insertions, 10 (2%) reinsertions and 297 (69%) revisions; 206 (69%) of the revisions were due to shunt failures, of which 74 (36%) were caused by the failure of the surgical technique (misplaced ventricular catheters, disconnected shunts, or misplaced peritoneal catheters). Conclusions: Improvement of the surgical technique may reduce the incidence of shunt failures and revisions. The results obtained in a small department like ours do not seem to differ substantially from those obtained in more specialized departments with a larger patient group. Practical measures that may reduce the risk of shunt failures are suggested. 相似文献
100.
Svendsen DP Cutler DL Ronis RJ Herman LC Morrison A Smith MK Munetz M 《Community mental health journal》2005,41(6):775-784
The Ohio Department of Mental Health and five of Ohio's University-based Departments of Psychiatry have developed strong working partnerships that have improved the quality of psychiatric residency education and Ohio's mental health services. Strategies integral to Ohio's Public Psychiatry Model include identifying a strong champion, integrating expert consultation, and developing consensus expectations using a small amount of catalytic funding. Successful outcomes include the establishment of public psychiatry leadership roles in Ohio's community and academic settings; positive community-focused residency training experiences; revised curricula; and spin-off opportunities, such as "Coordinating Centers of Excellence" to accelerate adoption of evidence-based practices in community settings. 相似文献