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991.
Retention problems have been reported with the clinical use of indirect microfilled resin veneers. This study used 24-hour shear tests to assess the bond strengths of such a resin veneer compared with other veneer types. The effect of different resin luting cements and resin veneer surface treatments were analyzed to elucidate factors by which retention could be increased. The six resin luting systems investigated showed a range of bond values. Debonding occurred primarily at the veneer/cement interface. G-Cera material produced the weakest bonds to Isosit-N resin. Surface treatment of Isosit-N veneers resulted in bond strength changes. Sandblasting reduced the force required for bond failure; Special Bond resin increased it slightly. Improving retention of prefabricated resin veneers proved difficult. Etched hybrid resin veneers delivered higher bond strengths than micro-filled resin veneers but not significantly. Etched porcelain veneers, however, provided consistently the strongest bond strengths with cohesive, as opposed to adhesive, bond failure. 相似文献
992.
Kurz SG Hansen KK McLaughlin MT Shivaswamy V Schaffer BS Gould KA McComb RD Meza JL Shull JD 《Endocrinology》2008,149(8):3850-3859
Ept1, Ept2, Ept6, and Ept9 are quantitative trait loci mapped in crosses between the ACI and Copenhagen (COP) rat strains as genetic determinants of responsiveness of the pituitary gland to estrogens. We have developed four congenic rat strains, each of which carries, on the genetic background of the ACI rat strain, alleles from the COP rat strain that span one of these quantitative trait loci. Relative to the female ACI rats, female ACI.COP-Ept1 rats exhibited reduced responsiveness to 17beta-estradiol (E2) in the pituitary gland, as evidenced by quantification of pituitary mass and circulating prolactin, and in the mammary gland, as evidenced by reduced susceptibility to E2-induced mammary cancer. The ACI.COP-Ept2 rat strain exhibited reduced responsiveness to E2 in the pituitary gland but did not differ from the ACI strain in regard to susceptibility to E2-induced mammary cancer. Interestingly, female Ept2 congenic rats exhibited increased responsiveness to E2 in the thymus, as evidenced by enhanced thymic atrophy. The ACI.COP-Ept6 rat strain exhibited increased responsiveness to E2 in the pituitary gland, which was associated with a qualitative phenotype suggestive of enhanced pituitary vascularization. The ACI.COP-Ept9 rat strain exhibited reduced responsiveness to E2 in the anterior pituitary gland, relative to the ACI rat strain. Neither Ept6 nor Ept9 impacted responsiveness to E2 in the mammary gland or thymus. These data indicate that each of these Ept genetic determinants of estrogen action is unique in regard to the tissues in which it exerts its effects and/or the direction of its effect on estrogen responsiveness. 相似文献
993.
994.
Our objective was to assess the influence of preliminary counseling that provided information about age-related fertility rates on the decision of women to undergo reversal of sterilization. There was no apparent influence; this raises the question as to whether couples seeking fertility therapy base their decision making on factual information provided by the clinician. 相似文献
995.
In vitro fertilization/embryo transfer (IVF/ART) results have shown significant improvements during the last decade. In the United States the rate of live births per cycle improved gradually to become 27% in 2001. Assisted reproductive techniques (ARTs) are increasingly being used for the treatment of tubal factor infertility. In this review the data are derived largely from our department, where we have treated sufficient numbers of patients and have maintained substantial consistency in our surgical techniques. This 3-part review demonstrates a high success rate of intrauterine pregnancy (IUP) after anastomosis for sterilization reversal. This rate, for those who are < 35 years of age at the time of reversal, is >70%, with most pregnancies occurring within 18 months after surgery. Those who are 35 years of age or more will have a 55% rate of IUP. We note, too, the satisfactory IUP rate (50%) after tubocornual anastomosis for proximal tubal disease. We document the beneficial role of laparoscopic salpingoovariolysis, fimbrioplasty and salpingostomy performed during the initial diagnostic laparoscopy. The IUP rates after salpingoovariolysis and fimbrioplasty are 60% and 50%, respectively. The rates of IUP for salpingostomy are modest in comparison, yet they are 25% for liberal use of salpingostomy during the preliminary laparoscopy. Salpingostomy also provides a beneficial effect upon embryo implantation in both in vivo and in vitro attempts at conception. This stresses the need for an appropriate preliminary investigation and for the subsequent diagnostic laparoscopy to be performed at a center able to perform these procedures. The evidence suggests that surgery should retain its place in the treatment of tubal infertility. Surgery and ART are complementary approaches that can be used singly or in combination to improve the outcome for couples with tubal infertility. 相似文献
996.
Markopoulou K Dickson DW McComb RD Wszolek ZK Katechalidou L Avery L Stansbury MS Chase BA 《Acta neuropathologica》2008,116(1):25-35
Individuals with familial Parkinson’s disease (PD) due to a monogenic defect can show considerable clinical and neuropathological
variability. To identify factors underlying this variability, histopathological analysis was performed in two clinically different
A53T α-synuclein heterozygotes from Family H, a multigenerational α-synuclein A53T kindred. To determine whether additional
genetic factors could contribute to phenotypic variability, Family H and another multigenerational A53T kindred were analyzed
for parkin polymorphisms. We identified a previously described variant in parkin exon 4 associated with increased PD risk (S167N). The two A53T heterozygotes had markedly different neuropathology and different
parkin genotypes: A N167 homozygote had early onset rapidly progressive disease, early dementia, myoclonus and sleep disorder, while
a S167 homozygote had late onset, slowly progressive disease and late dementia. Both had brainstem, cortical, and intraneuritic
Lewy bodies (LB). The N167 individual had widespread cortical neurofibrillary degeneration, while the S167 individual had
only medial temporal lobe neurofibrillary degeneration. The N167 individual had severe neuronal loss in CA2 associated with
Lewy neurites (LN), while the S167 individual had severe neuronal loss in CA1 associated with TDP-43 immunoreactive neuronal
inclusions. These findings implicate TDP-43 in the pathology of familial PD and suggest that parkin may act as a modifier of the A53T α-synuclein phenotype of familial PD. Furthermore, they suggest a mechanism by which a
rare genetic variant that is associated with a minor increase of PD risk in the heterozygous state may, in the homozygous
state, exacerbate a disease phenotype associated with a highly penetrant dominant allele. 相似文献
997.
998.
GW Roberts VV Master RE Staugas JV Raftos DW Parsons KP Coulthard & AJ Martin 《Journal of paediatrics and child health》1999,35(2):170-174
OBJECTIVE: To investigate the efficacy and tolerance of 12-hourly dosing with 2 mg 4 mL-1 of inhaled budesonide versus placebo in patients admitted to hospital with moderate/severe croup. METHOD: Eighty-two children hospitalised with croup received either 2 mg 4 mL-1 of budesonide or placebo 12 hourly (maximum four doses) via Ventstream nebuliser in a randomised, double-blind manner. Croup scores were performed at 0, 2, 6, 12, 24, 36 and 48 h from initial nebulisation whilst the patient remained hospitalised. Follow-up assessments were made 1 and 3 days after discharge. RESULTS: Improvement was observed in the budesonide group over the 12-h dosing interval when compared to placebo (P = 0.04). Time to attain a significant clinical improvement was superior in the budesonide group (P = 0.01). Three days after discharge seven of 32 placebo-treated patients and one of 34 budesonide-treated patients had sought further medical follow-up (P = 0.02). CONCLUSION: Twelve-hourly dosing with inhaled budesonide significantly improved symptoms of croup as well as decreased relapse rates when compared with placebo. 相似文献
999.
S.A. Koepsell A.G. Freifeld A.R. Sambol R.D. McComb S.A. Kazmi 《Transplant infectious disease》2010,12(5):459-464
S.A. Koepsell, A.G. Freifeld, A.R. Sambol, R.D. McComb, S.A. Kazmi. Seronegative naturally acquired West Nile virus encephalitis in a renal and pancreas transplant recipientTranspl Infect Dis 2010: 12: 459–464. All rights reserved Abstract: West Nile virus (WNV), a single‐stranded RNA flavivirus, has spread across the United States since arriving in 1999. While asymptomatic or self‐limited in a majority of patients, WNV can cause a severe neuroinvasive disease, which occurs more often in transplant recipients with chronic immunosuppression. Diagnosis of acute WNV infection usually relies on serologic identification of immunoglobulin M (IgM) specific for the virus. We report a fatal case of naturally acquired WNV encephalitis in a renal and pancreas transplant recipient who was seronegative for WNV‐specific IgM but had detectable WNV RNA by nucleic acid amplification testing (NAAT) several weeks after the onset of symptoms. This case demonstrates the importance of using both serologic assays and NAAT for WNV in transplant recipients with the clinical suspicion of encephalitis. 相似文献