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131.

Purpose  

The tumor suppressor gene PTEN negatively regulates Akt, a downstream mediator phosphoinositol 3-kinase. Several studies have reported the role of PTEN gene in Akt downregulation and apoptosis induction in different cancers and cell lines. However, the role of loss of PTEN expression in Akt activation and spontaneous apoptosis in oral squamous cell carcinoma clinical specimens is not well established.  相似文献   
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A 76-year-old man was admitted to our institution for elective exchange of his implanted cardioverter-defibrillator generator. Nine years earlier, he had been diagnosed with nonischemic cardiomyopathy and nonsustainable ventricular tachycardia. At that time, he had received a single-chamber implanted cardioverter-defibrillator, which was upgraded to a dual-chamber implanted cardioverter-defibrillator 3 years later. In the course of the current admission, routine device interrogation during exchange of the patient's implanted cardioverter-defibrillator generator revealed 150 episodes of ventricular tachycardia in the preceding 7 months, 137 of which had been successfully treated by antitachycardia pacing therapy without shock. These findings show the remarkable effectiveness of antitachycar-dia pacing in terminating ventricular tachycardia while preventing the delivery of shocks, minimizing patient discomfort, and avoiding implanted cardioverter-defibrillator battery depletion.  相似文献   
135.
Introduction : Mesenteric cysts (MC) are rare intra-abdominal tumors. The incidence has been estimated to be 1/100000 in the adult population and 1/20000 in children, with a male: female ratio of 1:1. The first successful laparoscopic resection of a MC was reported by Mackenzie et al. in 1993. The malignant transformation appears in 3% of cases. In our study, we presented the feasibility and results of laparoscopic resection. Case Reports : We report two cases of mesenteric cysts removed by a laparoscopic procedure.

Results : Laparoscopic approach in the two cases was successful. No conversion was observed. No complication occurred. The histopathological studies revealed no malignancy. After 18 months of follow-up the 2 patients remained free of disease.

Conclusion : In selected cases, safe and complete resection of MC could be achieved by laparoscopic approach. Complete surgical resection of MC is the treatment of choice when the cyst becomes symptomatic or when complications occur.  相似文献   
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In more than half of infertile men,the cause of their infertility is unknown.Several studies revealed the role of viral infections in male infertility.The aim of the present study was to determine the prevalence of herpes simplex virus-1 (HSV-1) and HSV-2 in semen from asymptomatic infertile male patients,and its association with altered semen parameters.A total of 70 semen samples were collected from infertile men who attended the Research and Clinical Center for Infertility in Yazd,Iran.Semen analysis and diagnostic real-time PCR using specific primers and probes for HSV-1 and HSV-2 DNA were performed.Comparison of semen parameters between virally infected and non-infected samples were performed with independent t-test and Mann-Whitney test.Semen analysis showed that infertile men fell into two groups,the male factor group and the unexplained group.HSV-1 and HSV-2 DNA was detected in 16 (22.9%) and 10 (14.3%) of 70 semen samples,respectively.All HSV-positive samples had abnormal semen parameters (the male factor group).Although HSV infection was not associated with sperm motility and morphological defects,it was correlated with lower sperm count in the seminal fluid.The findings suggest that asymptomatic seminal infection of HSV plays an important role in male infertility by adversely affecting sperm count.  相似文献   
137.
Hydroxyapatite (HAp) is the major mineral constituent of vertebrate bones and teeth. It has been well documented that HAp nanoparticles can significantly increase the biocompatibility and bioactivity of man-made biomaterials. Over the past decade, HAp nanoparticles have therefore increasingly been in demand, and extensive efforts have been devoted to develop many synthetic routes, involving both scientifically and economically new features. Several investigations have also been made to determine how critical properties of HAp can be effectively controlled by varying the processing parameters. With such a wide variety of methods for the preparation of HAp nanoparticles, choosing a specific procedure to synthesize a well-defined powder can be laborious; accordingly, in the present review, we have summarized all the available information on the preparation methodologies of HAp, and highlighted the inherent advantages and disadvantages involved in each method. This article is focused on nanosized HAp, although recent articles on microsized particles, especially those assembled from nanoparticles and/or nanocrystals, have also been reviewed for comparison. We have also provided several scientific figures and discussed a number of critical issues and challenges which require further research and development.  相似文献   
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The impact of platelet collagen receptor polymorphisms in the pathogenesis of myocardial infarction at young age remains unknown. To determine whether either of the two platelet collagen receptor polymorphisms (GP VI T13254C and GP Ia C807T) was associated with premature acute myocardial infarction. One hundred patients with premature acute myocardial infarction and 100 age-matched controls with normal coronary angiograms were studied. Genotyping was done using PCR followed by restriction fragment length polymorphism (RFLP). GP Ia C807T polymorphism was more frequent in the patient group (65%) than in the control group (53%). However, there was no association between this polymorphism and premature acute myocardial infarction (P?=?0.08). The prevalence of T13254C polymorphism did not differ between patients (38%) and controls (33%), and this polymorphism was not associated with premature acute myocardial infarction (P?=?0.46). Logistic regression analysis also indicated no association between these polymorphisms and premature acute myocardial infarction (C807T with P?=?0.51 and T13254C with P?=?0.20). There is no association between GP VI T13254C or GP Ia C807T polymorphisms and premature acute myocardial infarction.  相似文献   
140.
Aim: To assess the specific effect of alcohol dependence (AD) or heroin dependence (HD) in patients and their spouses on the risk of psychopathology in their 276 6.0- to 17.9- year-old children (mean 11.3 years). Methods: The sample included 101 offspring of patients with AD, 23 of patients with HD, and 152 of medical controls, as well as their 2 parents. Participants were assessed using semistructured diagnostic interviews and family history reports by psychologists blind to patient diagnoses. Results: Children of HD and AD patients had largely elevated rates of recurrent major depressive disorder. Children of HD patients were also at an increased risk for attention deficit hyperactivity disorder and substance use disorders (SUD). There were interactions between SUD in the 2 parents to increase the risk of SUD in offspring. Conclusions: These results emphasize the need for prompt identification and treatment of these children and highlight the need to pay clinical attention not only to the patient, but also to the co-parent in order to optimize prevention in offspring.  相似文献   
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