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971.
Morbidity and mortality from cardiovascular disease have a devastating impact on patients with chronic kidney disease (CKD) and end-stage renal disease. Renal function decline in itself is thought to be a strong risk factor for cardiovascular disease (CVD). In this study, we investigated the hypothesis that the elevated CV mortality in kidney transplant patients is due to the preexisting CVD burden and that restoring renal function by a kidney transplant might over time lower the risk for CVD. We analyzed 60,141 first-kidney-transplant patients registered in the USRDS from 1995 to 2000 for the primary endpoint of cardiac death by transplant vintage and compared these rates to all 66813 adult kidney wait listed patients by wait listing vintage, covering the same time period. The CVD rates peaked during the first 3 months following transplantation and decreased subsequently by transplant vintage when censoring for transplant loss. This trend could be shown in living and deceased donor transplants and even in patients with end-stage renal disease secondary to diabetes. In contrast, the CVD rates on the transplant waiting list increased sharply and progressively by wait listing vintage. Despite the many mechanisms that may be in play, the enduring theme underlying rapid progression of atherosclerosis and cardiovascular disease in renal failure is the loss of renal function. The data presented in this paper thus suggest that the development or progression of these lesions could be ameliorated by restoring renal function with a transplant.  相似文献   
972.
Generalized diminished root formation is a rare condition leading to early loss of teeth. This report describes an unusual case of generalized short roots associated with microdontia, taurodontism of posterior teeth, and multiple dens invaginatus along with short stature in a 20-year-old man, who had lost several teeth because of spontaneous exfoliation.  相似文献   
973.
974.
Epidermoid cysts of the testis are rare benign lesions that clinically resemble intratesticular neoplasms. Preoperative testicular ultrasound and an operative frozen section biopsy may help to establish the diagnosis without resorting to orchiectomy. In such selected cases local excision alone should be considered adequate without violating accepted surgical principles.  相似文献   
975.
Claims that women who have elective abortions will experience psychological distress have fueled much of the recent debate on abortion. It has been argued that the emotional sequelae of abortion may not occur until months or years after the event. Despite unclear evidence on such a phenomenon, adverse mental health outcomes of abortion have been used as a rationale for policy-making. We systematically searched for articles focused on the potential association between abortion and long-term mental health outcomes published between January 1, 1989 and August 1, 2008 and reviewed 21 studies that met the inclusion criteria. We rated the study quality based on methodological factors necessary to appropriately explore the research question. Studies were rated as Excellent (no studies), Very Good (4 studies), Fair (8 studies), Poor (8 studies), or Very Poor (1 study). A clear trend emerges from this systematic review: the highest quality studies had findings that were mostly neutral, suggesting few, if any, differences between women who had abortions and their respective comparison groups in terms of mental health sequelae. Conversely, studies with the most flawed methodology found negative mental health sequelae of abortion.  相似文献   
976.
PURPOSE: Thromboelastography (TEG) evaluates the visco-elastic properties of whole blood to assess clot formation and hemostasis. When blood cannot be analyzed immediately, it is stored in citrated tubes to be analyzed after recalcification. In this study, we evaluated the results of TEG analysis performed on citrated blood and compared these results to values obtained from activated (kaolin and tissue factor) and non activated, fresh blood samples, obtained at various time intervals (one, two, and three hours). METHODS: Four blood samples were collected from each of ten healthy volunteers. The following TEG analyses were performed on each sample: reaction time (r), k time (k), alpha angle (alpha), and maximum amplitude (MA). Studies were done using fresh, non citrated blood, obtained within five minutes of collection, and using citrated blood, one, two, and three hours after collection. Samples were analyzed, with and without activation, using kaolin and tissue factor. RESULTS: Tissue factor activated and non activated, citrated samples had shorter r and k times (P=0.03, P=0.008, P<0.0001, and P<0.0001, respectively) and higher alpha angle and MA values (P<0.0001, P<0.0001, P=0.79, and P=0.03, respectively) compared to fresh, non citrated samples. These findings were consistent with a hypercoagulable state. Conversely, citrated samples, activated with kaolin, yielded results similar to those obtained from fresh, non citrated samples. The TEG measurements were similar among citrated samples stored from one to three hours. CONCLUSIONS: Our results demonstrate that TEG measures, performed on citrated blood samples, yield results that are consistent with a hyperocoagulable state. Using kaolin to activate citrated samples, on the other hand, yields results similar to those obtained from non citrated, fresh blood samples.  相似文献   
977.
A bstract Background: In patients with absent pulmonary valve syndrome, the relief of the pulmonary regurgitation at the time of primary repair improves both the early and late results. Though homograft and heterograft valves and conduits have been used for this purpose, both are not easily available and are known for late failure. Monocusp and bicuspid semilunar valves made out of pericardium have their own problems. Hence, a technique of reconstructing an autologous competent 3-cusp valve from the native tissues was developed. Methods : Two posterolateral semilunar cusps were fashioned from the anterior wall of the main pulmonary artery. The anterior cusp was made from autologous pericardium stitched to the autologous pericardial patch used to widen the right ventricular outflow tract. Results : This method of reconstruction was used in two patients aged 9 and 22 years, respectively. Visual assessment and passive testing after reconstruction revealed well functioning neopulmonary valves in both patients. The second patient, who had an unevenful hospital course, showed only mild pulmonary regurgitation at 5 years postreconstruction. Conclusions : As 2 of the 3 cusps are fashioned from the pulmonary arterial wall as a pedicled graft, we believe that they will retain their viability and grow with the pulmonary artery. Simultaneous reduction in the size of the pulmonary arteries will relieve bronchial compression when present. The anterior pericardial cusp, even if it eventually shrivels up, is unlikely to produce serious hemodynamic derangements.  相似文献   
978.
A 14-year-old boy presented with spontaneous, painless proptosis of the right eye. Computed tomography and digital subtraction angiography revealed an indirect carotid cavernous fistula. Because there were no sight-threatening complications, we adopted a conservative approach. The condition resolved 1 month after initial presentation, with angiographically confirmed spontaneous obliteration of the fistula.  相似文献   
979.
OBJECTIVE: Decreased conjugation is probably more important than hemolysis for causing jaundice in G6PD-deficient neonates. The role of enzyme inducers, like phenobarbital, in G6PD deficiency is unclear. This randomized controlled trial was performed to evaluate Phenobarbital's role in reducing the need for phototherapy among G6PD-deficient neonates. STUDY DESIGN: This stratified, randomized, triple-blinded, placebo-controlled trial was conducted in a level III NICU. Consecutive babies with gestation >/=34 weeks and birth weight >/=1800 g were screened from cord blood. G6PD-deficient neonates, who were otherwise healthy, were enrolled. Rh isoimmunization, maternal Phenobarbital use and lack of parental consent were exclusion criteria. Subjects were randomly allocated to receive 5 mg/kg day of oral phenobarbital/ placebo for first 3 days. They were monitored daily for total serum bilirubin (TSB) until declining TSB was documented twice. The primary outcome was requirement for phototherapy and secondary outcomes were duration of phototherapy, need for exchange transfusion, peak TSB and adverse effects. Sample size of 56 could detect a decline in phototherapy requirement from 40 to 5% with 80% power and 5% error. RESULTS: Of 2370 babies screened, 63 were G6PD-deficient. Of them, 56 eligible babies were allocated to phenobarbital (n=27) or placebo (n=29). The mean age of administration of the first dose was 18.55+/-7.3 h. In total, 44% in phenobarbital group and 41% in placebo group required phototherapy (p=1.0). There was no significant difference in exchange transfusion rates (18.5 vs 10%, p=0.46). No baby had adverse reactions. CONCLUSION: Prophylactic oral phenobarbital does not decrease the need for phototherapy or exchange transfusions in G6PD-deficient neonates.  相似文献   
980.
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