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31.
INTRODUCTION: Slipped capital femoral epiphysis (SCFE) is a common hip disorder in adolescents. Treatment can be associated with serious complications, mainly avascular necrosis (AVN). The objective of this study was to evaluate treatment outcomes and complications based on physeal stability at presentation. METHODS: We reviewed retrospectively all children treated for SCFE from 1990 through 2000 at the Children's Hospital of Eastern Ontario, Ottawa. RESULTS: Of a total of 87 patients (56 male) identified, 73 had slips classed as stable and 14, unstable; 42 involved the left side, 34 the right, and 19 were bilateral. Avascular necrosis (AVN) developed in 1 patient with a stable slip (morbidity 1.4%) and in 3 with unstable slips (21.4%; p = 0.001). Manipulative anatomical reduction was done in 11 cases (78.5%), all unstable slips. All slips complicated by AVN had been classified according to the traditional system as acute-on-chronic. Complication rates differed significantly between unstable slips (36%) and stable (20%). No statistically significant association was found between AVN and slip severity, time to fixation or use of reduction. CONCLUSIONS: The treatment of stable slips exhibits a lower incidence of AVN. These results nevertheless suggest that gentle reduction of unstable slips is safe and unaccompanied by an increase in complications. 相似文献
32.
33.
Glatiramer acetate is an immunomodulating drug used in the treatment of multiple sclerosis. It consists of a copolymer of amino acid residues in the same stoichiometric proportions as in myelin basic protein. Its mechanism of action is not entirely known and is probably multifaceted, with deletion of some immune cell populations and stimulation of others in these patients. Some mechanisms involve neuroprotectant effects. There is ample evidence of its efficacy in relapsing-remitting disease, using both clinical and imaging measures of disease activity, and in this paper we review the clinical and basic studies of this drug. Finally we discuss how some of its neuroprotectant effects may be useful in neurodegeneration such as is seen in more advanced cases of multiple sclerosis and other diseases such as amyotrophic lateral sclerosis and Parkinson’s disease. 相似文献
34.
Amr E Abbas F David Fortuin Bhavesh Patel Carlos A Moreno Nelson B Schiller Steven J Lester 《Journal of the American Society of Echocardiography》2004,17(8):834-838
BACKGROUND: Systemic vascular resistance (SVR) is an integral therapeutic component of patients with heart failure and shock. We hypothesized that the ratio of the peak mitral regurgitant velocity (MRV) (m/s) to left ventricular outflow time-velocity integral (TVI(LVOT)) (cm) by Doppler would provide a noninvasive correlate of SVR. METHODS: SVR was correlated to MRV/TVI(LVOT) in 33 patients undergoing right heart catheterization. Receiver operating characteristic curves were generated to determine the best-balanced sensitivity and specificity to identify SVR > 14 Wood units (WU) and <10 WU. RESULTS: MRV/TVI(LVOT) correlated well with SVR (r = 0.842, 95% confidence interval 0.7-0.92, P <.001, Y = 0.459 + 49.397*X). By receiver operating characteristics, MRV/TVI(LVOT) > 0.27 had a 70% sensitivity and a 77% specificity to identify SVR > 14 WU. MRV/TVI(LVOT) < 0.2 had a 92% sensitivity and a 88% specificity to identify SVR < 10 WU. CONCLUSION: Doppler echocardiography provides a reliable noninvasive assessment of SVR. 相似文献
35.
The Role of Donor Bone Marrow Infusions in Withdrawal of Immunosuppression in Adult Liver Allotransplantation 总被引:3,自引:0,他引:3
Panagiotis Tryphonopoulos reas G. Tzakis Debbie Weppler Rolando Garcia-Morales Tomoaki Kato Juan R. Madariaga David M. Levi Seigo Nishida Jang Moon Gennaro Selvaggi Arie Regev Caio Nery Pablo Bejarano Amr Khaled Gary Kleiner Violet Esquenazi Joshua Miller Philip Ruiz Camillo Ricordi 《American journal of transplantation》2005,5(3):608-613
We investigated the role of donor bone marrow cell (DBMC) infusions in immunosuppression withdrawal in adult liver transplantation. Patients enrolled were at least 3 years post-transplantation, with stable graft function. Forty-five (study group: G1) received DBMC, and 59 (control group: G2) did not. Immunosuppression was reduced by one third upon enrollment, by another third the second year of the study and was completely withdrawn the third year. Patient and graft survival were similar between the two groups. Although rejection episodes were significantly less in G1 the first 2 years of the study (35% vs. 57%, p = 0.016), there was no significant difference overall (74% vs. 81%, p = 0.14). Until February 2004, 20 patients, 10 in each group, were immunosuppression free for 1-3 years. Approximately 20% of long-term survivors of liver transplantation can successfully discontinue their immunosuppression. DBMC infusions, do not increase this likelihood. 相似文献
36.
Reinaldo Figueroa MD Edilberto Martinez MD Raisa P. Fayngersh MD Hong Jiang MD Hatim A. Omar MD Nergesh Tejani MD Michael S. Wolin PhD 《American journal of obstetrics and gynecology》1995,173(6):1800-1806
OBJECTIVE: Our objective was to determine whether the observed relaxation to lactate and other agents in placental vessels of normal pregnancies is altered in severe preeclampsia.STUDY DESIGN: Isolated placental arteries and veins from women with severe preeclampsia and uncomplicated term pregnancies were precontracted with prostaglandin F2α under 5% oxygen and 5% carbon dioxide with the balance nitrogen (Po2 35 to 38 torr) and then exposed to lactate (1 to 10 mmol/L, pH 7.4, n = 8 to 15), arachidonic acid (0.01 to 10 μmol/L, n = 6 to 13), nitroglycerin (1 nmol to 1 μmol/L, n = 4 to 12), or forskolin (0.01 to 10 μmol/L, n = 6 to 9). The response to lactate was also examined in placental vessels from appropriate-for-gestational-age preterm deliveries (n = 8) for comparison with a similar group with severe preeclampsia (n = 8). The t test and analysis of variance statistics were used.RESULTS: Relaxation to lactate was markedly inhibited in both placental arteries and veins of women with severe preeclampsia compared with vessels from uncomplicated term or preterm pregnancies. Responses to the other relaxing agents were not altered in the severely preeclampsia vessels.CONCLUSIONS: In severe preeclampsia absence of lactate-induced dilatation of placental vessels may contribute to the fetal complications associated with impaired blood flow and vasospasm. 相似文献
37.
The heat shock/oxidative stress connection 总被引:2,自引:0,他引:2
M. A. Pappolla M. Sos R. A. Omar K. Sambamurti 《Journal of molecular neuroscience : MN》1996,28(1-3):21-34
Involvement of free-radical oxidations in the aging process has been a topic of interest since Harman's original contribution.
Because of the close association between aging and Alzheimer disease (AD) and the qualitative similarity in the neuropathology
of both conditions, it has been proposed by many investigators that oxidative stress may be important in AD. If such modality
of injury was indeed involved, one should expect to find markers of oxidation and heat shock (since free radicals are key
mediators of heat-shock induction) in brains of patients with AD. In fact, several studies documented abnormal expression
of antioxidant enzymes and heat-shock proteins (HSP) along with other markers of oxidation in AD brains. We showed that abnormally
expressed antioxidant enzymes are topographically associated with senile plaques and neurofibrillary tangles, and that the
activity of these enzymes is (contrary to what one would expect) markedly reduced. These findings have recently been confirmed
by other investigators. Despite a large amount of evidence that suggests an association between oxidative stress and the pathogenesis
of AD, it is not yet known whether oxidative stress is a cause or consequence of the disorder. Future research efforts regarding
the oxidative stress hypothesis of AD should include attempts, at generating AD pathology by oxidative means in laboratory
animals, determining the role and integrity of the heat-shock response in AD, as well as that of various antioxidant systems,
growth factors, and hormones with antioxidant and neuroprotective properties. 相似文献
38.
A case is reported of a young patient with metastases from the breast presenting as rapidly growing gingival epulides. The initial gingival lesion appeared shortly after a bone scan had given no evidence of dissemination of the diagnosed breast cancer. Two further lesions appeared at different sites within 3 weeks. 相似文献
39.
França O 《The Hastings Center report》1988,18(4):S21-S22
The ethics of care for the terminally ill in Uruguay spring from deeply rooted attitudes which invest the physician with sole power to determine the course of treatment, even to prescribe painkilling drugs and to hasten death actively or passively, without collaboration from the patient's family. The paternal function attributed to the physician has not been questioned by any systematic reflection on biomedical ethics. However, conscientious physicians are interested in these issues and are well informed about the concerns of their foreign colleagues. 相似文献
40.
Donald L. Phillips James L. Pirkle Virlyn W. Burse John T. Bernert Jr. L. Omar Henderson Larry L. Needham 《Archives of environmental contamination and toxicology》1989,18(4):495-500
Twenty healthy adult humans had serum samples drawn on four occasions within a 24-hr period: after a 12 hr overnight fast, 4–5 hr after a high fat breakfast, at midafternoon, and the next morning after another 12 hr fast. Nonfasting samples had 22% to 29% higher mean concentrations (p < 0.05) than did fasting samples for polychlorinated biphenyls (PCBs, 4.81 vs 3.74 ng/g serum wt), hexachlorobenzene (HCB, 0.163 vs 0.134 ng/g serum wt), andp,p-dichlorodiphenyldichloroethylene (p,p-DDE, 6.74 vs 5.37 ng/g serum wt) measured by electron capture gas liquid chromatography. Total serum lipids were estimated from measurements of total cholesterol, free cholesterol, triglycerides, and phospholipids and were 20% higher in nonfasting samples than in fasting samples (7.05 g/L vs 5.86 g/L). When PCBs, HCB, andp,p-DDE concentrations were corrected by total serum lipids, results from fasting and nonfasting samples were not statistically different. Because of the differences in these chlorinated hydrocarbon concentrations observed with different sample collection regimens, meaningful comparison of analytical results requires standardizing collection procedures or correcting by total serum lipid levels. 相似文献