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1.
AIM: Venous obstruction following transvenous device implantation rarely cause immediate clinical problems. When lead revision or device upgrade is indicated, venous obstruction become a significant challenge. The aim of this study was to determine the predictors of venous obstruction after transvenous device implantation, and to asess likely effects of antiplatelet/anticoagulant drugs in preventing venous thrombosis. METHODS AND RESULTS: Between March 2005 and July 2006, contrast venography was performed in 100 patients who were candidates for generator change, lead revision, or device upgrade. Vessel patency was graded as either completely obstructed, partially obstructed (>70%), or patent. The incidence of venous obstruction was 26%, with 9% of patients having total obstruction and 17% of patients exhibiting partial obstruction. No statistically significant differences between obstructed and non-obstructed patients were seen for age, sex, indication for device implantation, atrial fibrillation, cardiothoracic ratio, insulation material, operative technique, device type, and manufacturer (all Ps > 0.05). In a univariate analysis, multiple leads (P = 0.033), and presence of dilated cardiomyopathy (P = 0.036) were associated with higher risk of venous obstruction, whereas anticoagulant/antiplatelet therapy (P = 0.047) significantly reduced incidence of venous obstruction. Multivariate logistic regression analysis showed that only number of the leads (P = 0.039, OR: 2.22, and 95% CI: 1.03-4.76) and antiplatelet/anticoagulant therapy (P = 0.044, OR: 2.79, and 95% CI: 0.98-7.96) were predictors of venous obstruction. CONCLUSION: Total or partial obstruction of the access veins occurs relatively frequently after pacemaker or ICD implantation. Multiple pacing or ICD leads are associated with an increased risk of venous obstruction, whereas antiplatelet/anticoagulant therapy appears to have a preventive effect on development of access vein thrombosis.  相似文献   
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AIM: To assess lens thickness measurements with anterior segment-optical coherence tomography (AS-OCT) in comparison with A-scan ultrasonography (A-scan US). METHODS: There were 218 adult subjects (218 eyes) aged 59.2±9.2y enrolled in this prospective cross-sectional study. Forty-three eyes had open angles and 175 eyes had narrow angles. Routine ophthalmic exam was performed and nuclear opacity was graded using the Lens Opacities Classification System III (LOCS III). Lens thickness was measured by AS-OCT (Visante OCT, Carl Zeiss Meditec, Dublin, CA, USA). The highest quality image was selected for each eye and lens thickness was calculated using ImageJ software. Lens thickness was also measured by A-scan US. RESULTS: Interclass correlations showed a value of 99.7% for intra-visit measurements and 95.3% for inter-visit measurements. The mean lens thickness measured by AS-OCT was not significantly different from that of A-scan US (4.861±0.404 vs 4.866±0.351 mm, P=0.74). Lens thickness values obtained from the two instruments were highly correlated overall (Pearson correlation coefficient=0.81, P<0.001), and in all LOCS III specific subgroups except in grade 5 of nuclear opacity. Bland-Altman analysis revealed a 95% limit of agreement from -0.45 to 0.46 mm. Lens thickness difference between the two instruments became smaller as the lens thickness increased and AS-OCT yielded smaller values than A-scan US in thicker lens (β=-0.29, P<0.001) CONCLUSION: AS-OCT-derived lens thickness measurement is valid and comparable to the results obtained by A-scan US. It can be used as a reliable noncontact method for measuring lens thickness in adults with or without significant cataract.  相似文献   
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ObjectiveInterleukin (IL)-38 is a newly discovered member of the IL-1 cytokine family with a proposed anti-inflammatory profile. We studied the probable role of this cytokine in the pathogenesis of two autoimmune diseases: multiple sclerosis (MS) and systemic sclerosis (SSc).Subjects and MethodsA total of 87 MS patients and 86 SSc patients (40 new and recently untreated cases and 46 treated cases) were selected for this study. Eighty-seven and 80 age- and sex-matched healthy subjects were included as controls for MS and SSc, respectively. Clinical and paraclinical features of the patients were recorded at the time of sampling. Serum IL-38 was measured by ELISA.ResultsLevels of serum IL-38 did not significantly differ between the total MS or SSc patients compared to controls. However, levels of IL-38 were significantly higher in newly diagnosed patients of MS (206.43 ± 38.97 pg/mL, p < 0.0001) than in those previously treated (158.04 ± 39.45 pg/mL). Similarly, new/recently untreated cases of SSc patients showed increased IL-38 levels (185.19 ± 36.27 pg/mL, p = 0.001) compared to treated patients (166.82 ± 33.08 pg/mL). IL-38 levels in newly diagnosed MS patients (p = 0.007) and new/recently untreated SSc patients (p = 0.032) were significantly higher than those in healthy controls.ConclusionThe higher serum levels of IL-38 in new or recently untreated cases of MS and SSc patients than in treated patients and healthy controls suggest the possible role of this cytokine in the development of these diseases or as part of a feedback loop to attenuate the inflammatory conditions in early stages of these diseases.  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   
6.

Introduction

The intracranial bridging veins are pathways crucial for venous drainage of the brain. They are not only involved in pathological conditions but also serve as important landmarks within neurological surgery.

Methods

The medical literature on bridging veins was reviewed in regard to their historical aspects, embryology, histology, anatomy, and surgery.

Conclusion

Knowledge on the intracranial bridging veins and their dynamics has evolved over time and is of great significance to the neurosurgeon.  相似文献   
7.

Introduction

The Scottish surgeon Robert Liston was an accomplished anatomist of the nineteenth century. The study of anatomy during this day was often overshadowed by the so-called resurrectionists. Conclusions: The present historic paper reviews the life and contributions of Robert Liston and discusses his fascination with childhood hydrocephalus.  相似文献   
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The effects of alexandrite laser (AL) on skin parameters such as melanin content, skin layer depth, elasticity, and density have not been investigated through biometric methods. We aim to assess the effect of AL on the skin parameters through biometric devices to determine whether it has positive effects on treated region. In this pretest-posttest study, we recruited patients who attended Laser Clinic of Skin and Stem Cell Research Center, Tehran University of Medical Sciences, Tehran, Iran, from January through December 2014. Patients had to be free of any dermatologic conditions and lesion at the site of treatment or any contraindication to laser therapy. Baseline measurements were performed and patients received four sessions of AL therapy (spot size, 12 mm; fluence, 12 J/cm2; and pulse width, 5 Hz) with 4-week intervals. Four weeks after the last treatment session, the same parameters were assessed that included skin color, transepidermal water loss (TEWL), dermis and epidermis density and depth (through skin ultrasonography), melanin content, erythema intensity, and skin elasticity. Biometric parameters of 33 patients (27 females [81.8 %]), with mean (SD) age of 35.7 (9.5)?years were evaluated. The mean percent changes of skin parameters were as follows: skin color, 5.88 % through Visioface and by 56.8 % through Colorimeter devices (became lighter); melanin content, ?15.95 %; TEWL, ?2.96 %; elasticity, +14.88 %; dermis depth ?19.01 %; and dermis density, +1580.11 % (P?<?0.001 for changes in each parameter). AL could decrease melanin content of the skin and make the skin thinner while it could increase elasticity and density of epidermis and dermis, which might indicate increased collagen content of skin.  相似文献   
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