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71.

Purpose

The present study aimed to evaluate whether combining the magnetic-activated cell sorting (MACS) with density-gradient (DG) or swim-up (SU) sperm separation techniques can improve sperm selection to obtain higher quality spermatozoa.

Methods

Two commonly used sperm selection techniques, SU and DG, were compared to MACS combined with either SU or DG. Spermatozoa obtained from normozoospermic (n?=?10) and oligozoospermic (n?=?10) cases were grouped as SU, DG, SU+MACS, and DG+MACS followed by the analysis of sperm morphology, motility, DNA integrity, and the levels of Izumo-1 and PLCZ proteins.

Results

Although spermatozoa obtained by SU or DG when combined with MACS have improved aspects when compared to SU or DG alone, results did not reach a statistically significant level. Moreover, separation with MACS caused a significant loss in the numbers of total and rapid progressive spermatozoa.

Conclusions

Considering the cost/benefit ratio, MACS application together with traditional techniques may only be preferred in certain cases having higher concentrations of spermatozoa, but it does not seem to be an ideal and practical sperm selection technique for routine use.
  相似文献   
72.
Background: Diagnosing cobalamin deficiency is critical, given the high prevalence of cobalamin deficiency particularly in developing countries. Measuring serum cobalamin levels is of limited diagnostic sensitivity, in other words its specificity and sensitivity are low. The present study investigated the changes in the levels of metabolic markers – plasma homocysteine, plasma methylmalonic acid (MMA) and urinary MMA – of cobalamin metabolism.

Methods: Plasma cobalamin and serum folic acid were studied in 206 pregnant women over the last four prenatal weeks. Plasma cobalamin, folic acid, homocysteine, MMA from umbilical cord blood and urinary MMA in newborns were studied.

Results: Plasma cobalamin values were low in 66% of the mothers. There was a positive correlation between maternal and neonatal plasma cobalamin values (r?=?0.72, p?<?0.001). B12 was strongly inversely associated with plasma MMA, urine MMA and plasma homocysteine. To predict cobalamin deficiency, sensitivities of plasma MMA, urinary MMA and homocysteine were 96.4%, 95.6% and 88.2%, respectively. And positive predictive values (PPV) were 96.2%, 96.9% and 86% for plasma MMA, urinary MMA and plasma homocysteine levels, respectively.

Conclusion: Plasma MMA and urinary MMA B12 are the most robust markers of cobalamin deficiency. As a non-invasive method, urinary MMA is a sensitive method in demonstrating cobalamin deficiency in the newborn.  相似文献   
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Soft tissue expansion is a mechanical process that increases the surface area of local tissue available for reconstructive procedures. In most cases, adjacent tissue that matches the recipient site in color, texture, and hair-bearing quality is preferred for tissue expansion. In this particular case with neurocutaneous syndrome, the defects that resulted from removal of parts of a giant hairy nevus overlying the latissimus dorsi muscle bilaterally were grafted with a split-thickness skin graft. Two expanders were then placed under the latissimus dorsi muscles. After full expansion of the grafted area, some part of the remaining nevus surrounding the grafted area was removed and the defects were covered with the expanded skin graft obtained after deflation of the expanders. The expanders placed under the latissimus dorsi muscle in the first operation were reused in the second operation to obtain a second expansion of the skin graft. After the second expansion of the skin graft, the expanders were deflated and another portion of the remaining nevus surrounding the grafted area was removed. The resulting defects were again covered with the excess expanded skin graft. Although repeated expansion of the skin graft is a time-consuming and laborious process, it eliminates the need for taking repeated skin grafts; it decreases skin graft donor site morbidity; it decreases possible infectious complications of tissue expansion by decreasing the number of surgical interventions to the expander pocket; and it increases the aesthetic outcome by keeping all the surgical scars around the grafted area without extending them into healthy surrounding skin.  相似文献   
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The aim of the study is to evaluate the efficacy and safety of retrograde intrarenal surgery (RIRS) to treat renal stones in preschool age (<7 years) children. From September 2005 to May 2013, a total of 65 children (31 boys and 34 girls) with 72 renal stones were treated using RIRS. Patients were considered stone-free when the absence of residual fragments was observed on imaging studies. In the presence of residual calculi >4 mm, a second-stage RIRS was performed. The pre-operative, operative and post-operative data of the patients were retrospectively analyzed. A total of 65 patients with a mean age of 4.31 ± 1.99 years (6 months–7 years) were included in the present study. The mean stone size was 14.66 ± 6.12 mm (7–30 mm). The mean operative time was 46.47 ± 18.27 min. In 5 (7.69 %) patients, the initial procedure failed to reach the renal collecting system and ended with the insertion of a pigtail stent. The stone-free rates were 83.07 and 92.3 % after the first and second procedures, respectively. Complications were observed in 18 (27.7 %) patients and classified according to the Clavien system. Post-operative hematuria (Clavien I) occurred in 6 (9.2 %) patients, post-operative urinary tract infection with fever (Clavien II) was observed in 10 (15.4 %) patients, and ureteral wall injury (Clavien III) was noted in 2 (3 %) patients. RIRS is an effective and safe procedure that can be used to manage renal stones in preschool age children.  相似文献   
79.
Moyamoya syndrome is a chronic, progressive occlussion of cerebrovascular arteries that leads to the development of characteristic collateral vessels. It is usually accompanied with sickle cell disease and other hemoglobinopathies. We report a 7-year-old boy, who admitted to our clinic with headache, diagnosed as moyamoya syndrome associated with sickle cell trait. To date, two such cases have been reported in the literature. As far as we know, this patient is the first child reported.  相似文献   
80.
Journal of Interventional Cardiac Electrophysiology - Aortic cusps might be the source of supraventricular or ventricular arrhythmias. For many years, aortic cusp ablation has been widely used to...  相似文献   
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