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71.

Background  

Low cardiac output (LCO) after corrective surgery remains a serious complication in pediatric congenital heart diseases (CHD). In the case of refractory LCO, extra corporeal life support (ECLS) extra corporeal membrane oxygenation (ECMO) or ventricle assist devices (VAD) is the final therapeutic option. In the present study we have reviewed the outcomes of pediatric patients after corrective surgery necessitating ECLS and compared outcomes with pediatric patients necessitating ECLS because of dilatated cardiomyopathy (DCM).  相似文献   
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73.
BACKGROUND/AIMS: Operations often cause impairment in respiration due to pain. This study was designed to compare the changes in pulmonary function tests after open and laparoscopic cholecystectomy. METHODOLOGY: Two groups of 35 patients were randomly set up. Each patient had 3 pulmonary function tests performed and 2 postero-anterior grid chest roentgenograms taken. All of these data were evaluated by the same group of investigators. RESULTS: After taking into consideration the difference between pulmonary function tests, values were not significant (P < or = 0.05). All pulmonary function test values decreased significantly on the 1st postoperative day (P < or = 0.05). When postero-anterior chest roentgenograms were compared no clinically evident atelectasis except 3 lineary was seen in the laparoscopic cholecystectomy group, whereas 5 lineary, 7 focal, and 3 segmentary atelectasia were encountered in the open cholecystectomy group (P < or = 0.05). CONCLUSIONS: We believe that laparoscopic cholecystectomy has more advantages when speaking of postoperative pulmonary function tests and atelectasia.  相似文献   
74.
Routine semen examination remains an important tool for the diagnosis and treatment in human subfertility. Of all semen parameters, sperm morphology seems to be one of the most powerful indicators of a man's fertilizing potential in vitro and in vivo. Lack of standardization of sperm morphology assessments remains the main reason for the usefulness of this parameter. The aim of this study was to analyze the agreement between the wet-stained preparations versus those stained with modified Diff-Quik for sperm morphology. A total of 100 unselected semen samples from infertile couples were analyzed. Sperm morphology was evaluated with unstained specimens and following modified Diff-Quik staining according to the strict (Kruger classification) criteria by two different examiners (intralaboratory blind assessment). Mean percentages of morphologically normal spermatozoa were identical on wet and stained preparation slides (4.79 vs. 4.61, p >.05). Wide divergence of results was found with respect to the percentage of sperm with head and midpiece defects with the two different preparations (p >.001). The percentage of sperm tail defects was similar in both methods (p >.05). Simple linear regression analysis between the two methods revealed very good correlation for the morphologically normal spermatozoa (r =.83), but poor correlation for the sperm head, midpiece, and tail defects (r =.25,.25, and.28, respectively). Wet preparation is suitable only for the morphologically normal spermatozoa, but to determine the percentage of the defective spermatozoa, staining the smear is recommended.  相似文献   
75.
There are few implant materials which have been successfully used for nasal reconstruction. Of these, the medpor implant is the most accepted alloplastic material for reconstruction of the nasal framework. Here, an unusual complication of a medpor implant in nasal reconstruction is presented. A 24-year-old medical student suffering from a saddle nose deformity after a primary rhino plasty was admitted to our department. The medpor nasal implant was used to restore the nasal dorsum. The surgical result was appreciated by the patient. No problem was encountered during two years after surgery. Recently, the patient suffered from an asymmetry of the nasal dorsum. The physical examination revealed a step on the nasal dorsum with caudal mobility of the implant. The nasal implant was suspected to be broken. Multislice CT scan and ultrasonographic imaging of the implant were obtained. The radiologic evaluation of the region confirmed the fracture of the medpor nasal implant. Nasal reconstruction with a medpor implant is a good choice with low complication rates. This is the first case in the literature reporting a broken medpor nasal implant. Moreover, in this study a new method is described for imaging the medpor implant material.  相似文献   
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77.
An overriding principle of development is that neurons become permanently postmitotic once they initiate differentiation. Work in our laboratory, however, has provided evidence for a population of progenitor cells in mammalian forebrain that express properties of differentiated neurons, even though they continue to divide. These neuronal progenitor cells are situated in the rostral migratory stream (RMS), which extends from a specialized portion of the subventricular zone surrounding the anterior tip of the lateral ventricle, referred to as the SVZa, to the middle of the olfactory bulb. As SVZa-derived cells migrate to the olfactory bulb, they undergo cell division, and they never deviate from the RMS. Once they reach their final destinations, they become terminally postmitotic interneurons. This Mini-Review concerns findings from our recent experiments designed to reveal the intrinsic and extrinsic mechanisms governing the proliferation and differentiation of the unique SVZa neuronal progenitor cells. We have investigated the role(s) of cell cycle regulatory proteins, in particular, the cell cycle inhibitor p19(INK4d), in the control of SVZa cell proliferation. Several studies have indicated that cells withdraw from the cell cycle once they express p19(INK4d). To begin to investigate whether p19(INK4d)(+) SVZa-derived cells are postmitotic, we analyzed the pattern of p19(INK4d) expression by the cells of the RMS. A pronounced gradient of p19(INK4d) expression was demonstrated; progressively more cells are p19(INK4d) immunoreactive as the olfactory bulb is approached. In addition, the capacity of p19(INK4d)(+) cells to incorporate bromodeoxyuridine was investigated. From the results of these studies, we conclude that SVZa cells in the RMS can successively down-regulate their expression of p19(INK4d) as they migrate and that they repeatedly exit and reenter the cell cycle while en route to the olfactory bulb. These studies led us to investigate whether bone morphogenetic proteins (BMPs) are involved in the regulation of SVZa cell proliferation and p19(INK4d) expression, because, elsewhere in the CNS, BMPs modulate cell proliferation and influence cell fate decisions. To determine the effects of BMP signaling on SVZa cell proliferation and differentiation, we altered the expression of the BMP receptor Ia (BMPR-Ia) using retrovirally mediated gene transfer. The cells in the SVZa encoding the wild-type BMPR-Ia exit the cell cycle and do not appear to migrate through the RMS. Conversely, both within the SVZa and along the RMS, the majority of SVZa-derived cells encoding a dominant-negative BMPR-Ia gene do not express p19(INK4d). These findings indicate that p19(INK4d) expression is suppressed when BMP signaling is inhibited. Furthermore, SVZa-derived cells with both augmented and inhibited BMP signaling retain their neuronal commitment. Collectively, these studies have revealed that SVZa cell proliferation and differentiation is under the control of several interacting intrinsic and extrinsic factors.  相似文献   
78.
Tamoxifen therapy and hepatic steatosis   总被引:2,自引:0,他引:2  
Tamoxifen has been used for a long time as a hormonal treatment in breast cancer. Recent studies in pre and postmenopausal women have shown that tamoxifen exhibits favorable effects on the lipid profile. In this study we investigated the effects of tamoxifen on lipid profile and hepatic steatosis. Fifty two (31 postmenopausal and 21 premenopausal) women with breast cancer treated with tamoxifen at a dose of 20 mg daily were included in the study. Serum lipid parameters (total cholesterol, high and low density lipoprotein cholesterol and triglyceride) were measured baseline and at the 6th month of tamoxifen treatment. Upper abdominal ultrasonography was performed before and at the 6th month of therapy for assessment of liver steatosis. We obtained decreased levels of serum total cholesterol after 6 months of tamoxifen treatment (p < 0.05). However, we did not detect any changes in triglyceride and high-density lipoprotein cholesterol levels (p > 0.05). Increased liver steatosis was observed in 22 patients (42.3%) after tamoxifen treatment. We could not detect increase in lipid levels in these patients. There was no significant difference between the lipid levels in the patients with increased liver steatosis and stable or no liver steatosis. Whether hepatic steatosis is dependent on lipid changes in tamoxifen use should be further investigated.  相似文献   
79.
A CASE REPORT: The authors report a case of rotational vertebro-basilar insufficiency causing "drop-attacks". To our knowledge, it is the first case of extraluminal vertebral artery compression caused by a fibrous band of the longus colli muscle, demonstrated by spiral computed tomographic angiography with volume rendering reformation.  相似文献   
80.
We report the ultrasound-guided direct percutaneous injection of n-butyl cyanoacrylate to embolize an iatrogenic peripheral pseudoaneurysm secondary in a 33-year-old patient undergoing hemodialysis. We protected the parent artery with inflation of an angioplasty balloon across the neck during the cyanoacrylate injection. Complete occlusion of the pseudoaneurysm was achieved without ischemic complication.  相似文献   
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