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101.
A consecutive series of 12 patients between the ages of 6 1/2 and 37 years underwent implantation of venous ventricle-pulmonary artery conduits. GORE-TEX material without prosthetic valves was used. Four patients had L-transposition of the great vessels with ventricular septal defect (VSD) and pulmonary stenosis; four had tetralogy of Fallot with pulmonary atresia; and one had double outlet right ventricle, pulmonary stenosis, and a complete form of A-V canal. Two patients had D-transposition of the great arteries, VSD, and pulmonary stenosis; and one patient had L-transposition of the great arteries and isolated pulmonary stenosis. All patients had low pulmonary resistance and pressures. The technique for implanting this noncrimped type of prosthesis is described in detail. Follow-up ranged from 2 months to 5 1/2 years. GORE-TEX offers a good choice of material for the construction of this type of conduit to prevent pseudointima formation and obstruction, which is often observed in woven Dacron grafts.  相似文献   
102.
The Effects of Magnetic Resonance Imaging on Implantable Pulse Generators   总被引:2,自引:0,他引:2  
The effects of magnetic resonance imaging were assessed on four dual chamber and two single chamber pulse generators. The tests were performed with a resistive, water-cooled magnet operating at 0.15 T. The 6.4-MHz radiofrequency (RF) field was operated at a maximum power of 1,000 watts with a period adjusted from 130 to 500 ms. Reed switch closure occurred in all six pulse generators tested when placed near the entrance of the magnetic resonance imaging scanner, and the generators reverted to asynchronous operation unless programmed to the "magnet off" mode. None of the pulse generators exhibited any alterations in programmed parameters or in the ability to be reprogrammed after RF pulsing. When the RF field was turned on, there was no change in the asynchronous paced cycle length in four pulse generators; however, during RF scanning there was rapid cardiac stimulation at the RF pulse period in one single chamber and one dual chamber pulse generator.  相似文献   
103.
104.
Background

 Under the Affordable Care Act, Medicaid expansion effective 1 January 2014 aimed to increase access to health care. We sought to determine the association of Medicaid expansion with disparities in utilization of breast reconstruction.

Methods

Non-Hispanic Black (NHB) and White (NHW) breast cancer patients undergoing mastectomy +/? reconstruction between 2010 and 2017 were selected from the National Cancer Database. Annual trends for utilization of breast reconstruction by race, income, and education were evaluated by Medicaid expansion status using difference-in-differences regression analyses. Medicaid expansion was categorized by expansion date as early (2010–2013), 2014 (1/2014), late (after 1/2014), or no expansion.

Results

Of 443,607 patients, 36.3% (n = 161,128) underwent reconstruction, 13.1% (n = 58,249) were NHB, 16.8% (n = 74,430) had median income < $40,227, and 17.1% (n = 75,718) were in the lowest education quartile. In non-expansion states, lower proportions of NHB patients underwent reconstruction than NHW patients in all years, with the smallest disparity (NHB% ? NHW%) (? 6.4%) in 2017. Decreases in disparities between NHB and NHW patients were seen with the smallest difference observed in 2014 (? 2.5%) in early-expansion states, in 2017 (? 0.7%) in 1/2014 expansion states, and in 2017 (? 4.5%) in late-expansion states. Similar findings for convergence of reconstruction utilization rates for the lowest two education levels and lowest two income quartiles were found with Medicaid expansion, with no convergence seen in non-expansion states over the study period.

Conclusions

Some improvement in breast reconstruction disparities followed Medicaid expansion. Failure to improve parity without Medicaid expansion should be a consideration with any modifications to Medicaid access.

  相似文献   
105.
BACKGROUND: AbobotulinumtoxinA (AboBoNT-A; Dysport®; Ipsen, Boulogne-Billancourt, France/Azzalure®; Galderma, Lausanne, Switzerland) is a botulinum neurotoxin type A approved for aesthetic use in the treatment of glabellar lines in adult patients under 65 years in Europe, the United States, and other countries. OBJECTIVE: We sought to analyze current literature on patient satisfaction with aboBoNT-A for upper facial aesthetic indications. METHODS: A systematic review of literature databases (PubMed/MEDLINE, Embase, the Cochrane Library, and Google Scholar) was performed to identify English-language publications reporting on patients with aesthetic indications (including glabellar lines and wrinkles) receiving aboBoNT-A, that assessed patient and/or physician satisfaction with treatment, with no restrictions on comparator studies. Structured data extraction was used to enable inter-study analysis. A post-hoc analysis was also performed to assess patient satisfaction by sex and age, using results from the noninterventional APPEAL study of patients’ satisfaction with aboBoNT-A for treating glabellar lines. RESULTS: Overall, 22 original research papers were identified. Patient satisfaction rates for aboBoNT-A treatment were significantly higher versus placebo from two weeks to between three and five months postinjection. At two to three weeks postinjection, patient satisfaction rates were 52% and 99% across studies. In studies with later time points, patient satisfaction rates were 85 to 87 percent at 5 months and between 25 and 100 percent at 6 months post-injection. Physician satisfaction was also high (97%–100%, across three treatments). No notable differences in patient satisfaction by sex or age were observed in the APPEAL study. CONCLUSION: High rates of patient satisfaction have been achieved with aboBoNT-A treatment for upper facial aesthetic indications. Despite the current recommended interval of ≥12 weeks, satisfaction with the aesthetic results of aboBoNT-A therapy is still evident up to 6 months post-injection in some patients.  相似文献   
106.
107.
Thymic masses on MR imaging   总被引:4,自引:0,他引:4  
MR imaging is an excellent technique for identifying and defining the extent of thymic tumors. T1-weighted spin-echo MR images (e.g., 600/15 [TR/TE]) best demonstrate tumor extent, and T2-weighted images (e.g., 2500/90 [TR/TE]) help differentiate "cystic" from solid thymic masses. Cyst formation and/or hemorrhage appear as areas of high signal intensity (greater than that of fat) on T2-weighted images. Focal areas of low signal intensity (less than that of muscle) correspond pathologically to fibrous capsules and septa, air, or calcification. In this report, the MR appearance of the normal thymus is reviewed briefly, and the gamut of abnormal thymic masses on MR is illustrated.  相似文献   
108.
The neurotoxic potential of N,N-diethyl-m-toluamide (DEET) wasevaluated following acute oral administration or following multigenerationplus chronic dietary administration to the rat. For the acutestudy, rats were administered undiluted DEET at dose levelsof 50, 200, or 500 mg/kg by gavage. A dose level of 500 mg/kgwas considered to be the highest practical dose that could beevaluated in this study based upon observations of overt toxicityat 500 mg/kg and mortality at 1000 mg/ kg in a dose range-findingstudy. The two measures of neurotoxicity evaluated in the acutestudy were functional observational battery (FOB) and motoractivity measurements. An apparent treatment-related effectin thermal response time (increased) was noted for both sexes1 hr after dosing at the 500 mg/kg dose level. A questionableeffect on rearing activity (decreased) also was noted at thesame dose level. For the multigeneration plus chronic dietaryadministration study, rats were administered DEET at dietaryconcentrations of 0, 500, 2000, or 5000 ppm continuously overtwo generations and then chronically for 9 months. A dietaryconcentration of 5000 ppm meets the criteria for a maximum tolerateddose (MTD) based on traditional chronic toxicology assessments.Evaluations included FOB, motor activity, discriminative acquisitionand reversal in an Mmaze, acoustic startle habituation, passiveavoidance acquisition and retention, and microscopic examinationof central and peripheral nervous tissue. The only effect thatwas considered to be possibly treatment-related was a slightincrease in exploratory locomotor activity at the 5000 ppm doselevel. Based on the results of these studies, the nervous systemdoes not appear to be a selective target when DEET is administeredto rats either as a single oral dose at high dose levels orchronically at the MTD.  相似文献   
109.
As little information is available on the adverse effects ofpolychlorinated biphenyls (PCBs) on the reproductive systemof the male rat, the current study was conducted to evaluatethe effects of subchronic administration of the PCB mixtureAroclor 1254 on testicular gamete production and endocrine function.The thyroid hormone thyroxine (T4), which is critical for reproductionand development, was also measured because of the well-documentedeffects of PCBs on this hormone. Weanling (31-day-old) maleFischer rats were administered 0, 0.1, 1, 10, or 25 mg/kg/dayAroclor 1254 by gavage for 5, 10, or 15 weeks and necropsied.The hormones testosterone (T) and thyroxine were measured inthe serum, and body weight and weights of the liver, kidney,testes, seminal vesicle plus coagulating gland, cauda epididymides,and pituitary were taken. At 10 and 15 weeks, testicular interstitialfluid (IF) was collected and T concentration in the IF was measured.Sperm motility was measured from a caudal sperm sample and spermnumbers in the testis and cauda epididymis were determined.In addition, tissues were examined microscopically for histopathologicalalterations. In the high-dose group, body, seminal vesicle,cauda epididymal, and pituitary weights were depressed at 10and 15 weeks and cauda epididymal sperm numbers were reducedafter 15 weeks of dosing. In contrast, testes weights, testicularsperm numbers, sperm motility, and serum and testicular testosteronelevels were unaffected, even in the highest dose group (25 mg/kg/day).Aroclor 1254 administration produced histological alterationsin the liver and kidney at doses of 1.0 mg/kg/day and above.These results indicate that the testis of the rat is not a specifictarget organ for Aroclor 1254. In contrast, serum T4 levelswere reduced by Aroclor 1254 administration at a dose 250-foldbelow the dose that failed to alter testicular function. SerumT4 levels were depressed 25% in the 1 mg/kg dose group after5 weeks of exposure and 30% in the 0.1 mg/kg group following15 weeks of exposure. T4 levels were undetectable in the twohighest (10 and 25) dose groups at all intervals. The fact thatthe decreases in T4 were generally concurrent with increasesin liver weight suggested that Aroclor 1254 altered T4 levelsby increasing the turnover rate in the serum by enhancing themetabolism of T4 by the liver. The reduction in serum T4 reportedhere occurred at a dose 25-fold lower than the dose generallyrecognized as affecting thyroid hormone levels.  相似文献   
110.
This study was undertaken to investigate a number of immuneparameters which may be compromised with exposure to morphinesulfate. Mice were implanted subcutaneously with 8-, 25-, or75-mg morphine sulfate pellets. Placebo pellets of identicalmakeup to the 75-mg morphine pellet (without morphine of course)were used as a control. Twenty-four hours after implantationof a 75-mg morphine pellet, blood levels reached a peak of 1610ng/ml. Corticosterone increased in parallel with morphine andreached a peak level of 966 ng/ml 24 hr after implantation.The dose response of morphine to increase corticosterone, however,was fiat. The weight of the lymphoid organs, spleen and thymus,and the liver were significantly reduced in the morphine-treatedgroups. Morphine treatment was associated with an increase inserum albumin, SGPT, BUN, and alkaline phosphatase indicativeof hepatic damage. In contrast to increased serum proteins,the C3 component of complement was reduced in a dose-dependentmanner. Leukocyte number in the peripheral blood was significantlyreduced, while erythro-cyte number and hematocrit were bothincreased. The number of B cells and T cells was decreased inmorphine-treated animals. However, the percentage of T cellsrelative to B cells was increased. The primary IgM antibodyresponse to the T-depen-dent antigen, sheep red blood cells,was decreased. Natural killer cell activity was reduced in responseto morphine, as was the phagocytic capacity of Kupffer cells.Host-resistance models of Listeria monocytogenes or Streptococcuspneumoniae showed an increased resistance following administrationof morphine. This increased host resistance, however, was notdue to an increase in antimicrobial action of sera obtainedfrom mice treated with morphine. The majority of morphine'seffects on the immune system exhibited a flat dose response,suggesting that these effects may be mediated secondarily throughcorticosterone.  相似文献   
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