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131.
BACKGROUND: Division of the sternum is primarily a blind procedure in reoperation and carries an increased risk of injury for major cardiac structures in the presence of adhesions between the posterior table and the heart. METHODS: Two hundred patients were randomly divided into two groups. Cardiopulmonary bypass was established through the femoral artery and vein in group 1 (n = 100) patients before sternal reentry. Carpentier dual-stage femoral venous return cannula was used in all group 1 patients. Cardiopulmonary bypass was performed after sternal reentry in group 2 (n = 100) patients. RESULTS: Six severe cardiac injuries developed in group 2. Cardiopulmonary bypass time was 93 +/- 9 minutes in group 1 and 71 +/- 11 minutes in group 2 (p = 0.011), and the operation time was 155 +/- 23 minutes in group 1 and 185 +/- 32 minutes in group 2 (p = 0.024). Inotropic therapy was required in 52 patients in group 1 and 76 patients in group 2 (p = 0.032). Average chest drainage was 450 +/- 135 mL in group 1 and 850 +/- 250 mL in group 2 (p < 0.001). Average fresh whole blood transfusion was 3.3 +/- 1.2 U in group 1 and 5.8 +/- 0.9 U in group 2 (p = 0.033). Average intensive care unit stay was 2.2 +/- 1.3 days in group 1 and 4.5 +/- 2.3 days in group 2 (p = 0.025). Average hospital stay was 7.3 +/- 2.4 days in group 1 and 9.1 +/- 3.1 days for group 2 (p = 0.011). CONCLUSIONS: Cardiopulmonary bypass by bicaval Carpentier femoral venous cannula before resternotomy not only allows adequate cardiopulmonary bypass flow but also significantly reduces the risk of cardiac injury and catastrophic hemorrhage and allows safe reopening. Although this procedure increases cardiopulmonary bypass time, the operation time, bleeding, and blood transfusion requirement are significantly reduced.  相似文献   
132.

Background/purpose

This study was carried out to evaluate the effects of local and sustained release of fibroblast growth factor (FGF) on testicular blood flow and morphology in spermatic artery— and vein-ligated rats.

Methods

Forty male Wistar albino rats weighting 300 ± 20 g were allocated randomly into 5 groups consisting of 8 in each as follows: G-S (sham); G-C (control); and G-T0.85, G-T1.70, G-T2.55. After the ligation of the left spermatic artery and vein, 1 cm2 of unloaded and 0.85 μg, 1.70 μg, and 2.55 μg of FGF-loaded gelatin films were sutured on the left epididymis in G-C, G-T0.85, G-T1.70, and G-T2.55, respectively. After 30 days, bilateral capsular (CBF) and intratesticular (IBF) blood flows were evaluated by colored Doppler ultrasonography (CDUS) and testicular blood flow (TBF) by 133Xe clearance technique. Tunica albuginea and intertubular tissues were studied for the increase of peritesticular and intratesticular vessels. Mean intertubular vascular structure counts, seminiferous tubular diameters, testicular biopsy scores, and Leyding cell scores of each group were recorded and compared.

Results

CBF was present in all animals of G-S, G-T0.85, G-T1.70, and G-T2.55 groups in CDUS, and it was detected in 62% of the G-C rats (P < .05). However, IBF was present in only 25% of the G-C rats, and this percentage was increased from 50% up to 87.5% for treatment groups, and 100% for G-S rats, respectively. 133Xe clearance showed that TBF was significantly decreased in G-C compared with G-S (P < .05). In G-T2.55, TBF was significantly increased, but still could not reach the level of G-S. Although mean testicular weights were significantly decreased for controls (G-C), G-T0.85, and G-T1.70, almost no difference was observed between G-T2.55 and G-S. Although a slight increase in the vascular structures of tunica albuginea was present in G-C rats, a significant increase was observed in treatment groups. The mean number of intertubular vascular structures was significantly increased in treatment groups when compared with G-S and G-C (P < .05). Mean seminiferous tubular diameters and Leydig cell scores were decreased in G-C but significantly increased in treatment groups (P < .05). Mean testicular biopsy scores were increased in treatment groups compared with G-C but could not reach to sham levels.

Conclusions

Ligation of the spermatic artery and vein has detrimental effects on the ipsilateral testicular blood flow and morphology. These effects may be reversed by local application of FGF.  相似文献   
133.
INTRODUCTION: Etiology of serum anti-p53 antibodies in bladder cancer patients is still unknown. In this study we evaluated the relationship between serum anti-p53 antibodies and microvessel density in bladder cancer patients. MATERIALS AND METHODS: Seventy-six patients with transitional cell carcinoma of the urinary bladder were assessed prospectively (18 Ta, 30 T1, 28 T2>or =). Serum anti-p53 antibodies were detected by enzyme-linked immunosorbent assay. Tumor p53 overexpression was assessed by immunohistochemical staining. Vessels were stained immunohistochemically using an antibody against platelet endothelial cell-adhesion molecule CD31. Spearman correlation test and t test were used for statistical analysis. RESULTS: Serum anti-p53 antibodies were positive in 25 (60%) of 41 tumor p53-positive patients. While the mean (SD, range) microvessel density was found to be 43 (7.59, 8-99) in patients who had positive serum anti-p53 antibodies, it was found to be 23 (4.53, 6-98) in patients who had negative serum anti-p53 antibodies. There was a good correlation between serum anti-p53 antibodies and microvessel density (p<0.05). No correlation was found between tumor p53 expression and microvessel density (p>0.05). CONCLUSIONS: We found that there is a significant correlation between the microvessel density and serum anti-p53 antibodies. This result may show the role of angiogenesis in the etiology of serum anti-p53 antibodies in bladder cancer patients.  相似文献   
134.
BACKGROUND: Cerebrovascular stability and rapid anesthetic emergence are desirable features of a neuroanesthetic regimen. In this randomized crossover study the effect of a low-dose remifentanil infusion on cerebral blood flow velocity (CBFV) in children anesthetized with propofol was evaluated. METHODS: Twenty healthy children aged 1-6 years undergoing urological surgery were enrolled. Following face mask induction with sevoflurane, anesthesia was maintained with a standardized propofol infusion. Rocuronium was used to facilitate tracheal intubation and normothermia, and normocapnia were maintained. All children received a caudal epidural block, and a transcranial Doppler probe was placed to measure middle cerebral artery blood flow velocity (Vmca). Each patient received a remifentanil regimen of 0.5 microg x kg(-1) followed by 0.2 microg x kg(-1) x min(-1) in a predetermined order of remifentanil + propofol or propofol alone. Vmca, mean arterial pressure (MAP) and heart rate (HR) were recorded simultaneously at equilibrium with and without remifentanil. RESULTS: The combination of remifentanil and propofol caused an 8.1% decrease in MAP (P = 0.0005) and an 11.8% decrease in HR (P < 0.0001) compared with propofol alone. Vmca was not different between the two groups (P = 0.4041). CONCLUSION: The addition of remifentanil to propofol anesthesia in children causes a reduction in MAP and HR without affecting CBFV. This may imply that cerebral blood pressure autoregulation is preserved in children under propofol and remifentanil anesthesia.  相似文献   
135.
PURPOSE: To evaluate whether repeated courses of high-dose methylprednisolone (HDMP) affect the lumbar spine bone mineral density (BMD) in children with chronic idiopathic thrombocytopenic purpura (ITP). MATERIALS AND METHODS: This study included 24 patients with chronic ITP and 149 healthy controls. The patients were allocated into three groups according to the number of HDMP courses (30 mg/kg per day as a single dose for 7 days); group 1 (10 patients), group 2 (9 patients), and group 3 (5 patients) had received less than 5, 6-10, and more than 10 courses, respectively. Lumbar spine BMD and body composition were measured using dual energy X-ray absorptiometry of lumbar spine (L2-L4), and volumetric bone mineral density (vBMD) values were calculated and compared with the controls. The z score of the vBMD was also calculated and compared in the patients of each other groups. Serum markers of the bone turnover were measured to exclude other factors that could effect BMD. RESULTS: The vBMD values of the patients, corrected BMDs for age, were significantly lower than the values of controls (P = 0.018). It was significantly lower in group 3 than groups 1 and 2 (P = 0.005 and P = 0.006, respectively), but there was no statistically significant difference between groups 1 and 2 (P = 0.87). The vBMD z scores were significantly lower in group 3 than in groups 1 and 2 (P = 0.003 and P = 0.004, respectively), and also in group 2 than in group 1 (P = 0.034). There were a weak negative correlation between the cumulative dose of HDMP and vBMD (r = -0.39, P = 0.054), and strong negative correlation between the cumulative dose of HDMP and vBMD z score (r = -0.63, P = 0.001). CONCLUSION: Children with chronic ITP are at risk for decreased BMD because of the repeated courses of HDMP; especially more than 2100 mg of cumulative dose. We therefore recommend that BMD should be monitored in patients with chronic ITP who received repeated courses of HDMP.  相似文献   
136.
The intestinal Na-dependent D-glucose co-transporter (SGLT)-1 in sheep is under dietary regulation by luminal substrates. The aim of the present study was to find out whether the SGLT-1 in the forestomach of sheep is also regulated by sugars. Furthermore, the location of a possible glucosensor (luminal v. intracellular v. basolateral) was to be elucidated. Ruminal epithelia of sheep (Ovis aries, Merino breed) were pre-incubated in Ussing chambers with various substrates on the mucosal (i.e. luminal) or serosal (i.e. blood) side. This pre-incubation period was followed by a second pre-incubation period without the tested substrates (washout period). Thereafter, apical D-glucose uptake by ruminal epithelial cells was determined with 200 mumol D-[(14)C]glucose/l in the absence or co-presence of the SGLT-1 inhibitor, phlorizin. Pre-incubation with D-glucose on the mucosal side had no significant effect on apical D-glucose uptake (P>0.05). In contrast, pre-incubation with D-glucose, D-mannose, 3-O-methyl-d-glucose or sucrose on the serosal side significantly increased D-glucose uptake compared with mannitol-treated controls (P<0.05). Serosal pre-incubation with cellobiose or D-xylose had no effect. The stimulation of d-glucose uptake by serosal D-glucose pre-incubation was concentration dependent, with maximal stimulation at about 10 mmol/l. We conclude that the ruminal SGLT-1 can be up-regulated in a concentration-dependent manner by blood-borne D-glucose via an extracellular sugar-sensing mechanism.  相似文献   
137.
PURPOSE: To determine the short-term effects of latanoprost on retrobulbar circulation in ocular hypertension. METHODS: Forty-six eyes of 23 consecutive bilateral ocular hypertensive patients with an intraocular pressure (IOP) of greater than 22 mmHg were evaluated in a prospective controlled study. All subjects received a single drop of latanoprost 0.005% in one eye and placebo in the fellow control eye. Systemic circulatory parameters, intraocular pressure, blood flow velocities, and resistance indices of the ophthalmic, short posterior ciliary and central retinal arteries were measured using colour Doppler imaging at baseline and 2 h and 8 h after dosing. RESULTS: Latanoprost lowered IOP significantly after 2 h and 8 h (P < 0.01). The mean IOP reduction was 6.7 mmHg 8 h after dosing. At baseline, there were no statistically significant differences in any retrobulbar vessels of eyes that received a single drop of latanoprost when compared with the eyes that received placebo (P > 0.05). Comparisons with baseline and latanoprost conditions revealed that latanoprost did not alter the blood flow velocities and resistance indices in the ophthalmic (P > 0.05), posterior ciliary (P > 0.05) and central retinal (P > 0.05) arteries 2 h and 8 h after dosing. The systolic and diastolic blood pressures (p = 0.74, p = 0.29, respectively) and pulse rate (p = 0.68) remained unchanged over the 8-h period. CONCLUSIONS: This study found that a single drop of latanoprost significantly reduces intraocular pressure 8 h after dosing. However, it does not have any short-term effects on the retrobulbar haemodynamics in ocular hypertensive eyes.  相似文献   
138.
139.
BACKGROUND: Long latency reflexes (LLR) include afferent sensory, efferent motor and central transcortical pathways. It is supposed that the cortical relay time (CRT) reflects the conduction of central transcortical loop of LLR. Recently, evidence related to the cortical involvement in multiple sclerosis (MS) has been reported in some studies. Our aim was to investigate the CRT alterations in patients with MS. METHODS: Upper extremity motor evoked potentials (MEP), somatosensory evoked potentials (SEP) and LLR were tested in 28 patients with MS and control subjects (n=22). The patients with MS were classified according to the clinical form (relapsing-remitting [R-R] and progressive groups). The MS patients with secondary progressive and primary progressive forms were considered as the "progressive" group. CRT for LLR was calculated by subtracting the peak latency of somatosensory evoked potentials (SEP) and that of motor evoked potentials (MEP) by transcranial magnetic stimulation from the onset latency of the second component of LLR (LLR2) (CRT = LLR2 - [MEP latency + N20 latency]) RESULTS: Cortical relay time was calculated as 7.4 +/- 0.9 ms in control subjects. Cortical relay time was prolonged in patients with MS (11.2 +/- 2.9 ms) (p<0.0001). The latencies of LLR, MEP and SEP were also prolonged in patients with MS. Cortical relay time was not correlated with disease severity and clinical form in contrast to other tests. CONCLUSIONS: Our findings suggested that CRT can be a valuable electrophysiological tool in patients with MS. Involvement of extracortical neural circuits between sensory and motor cortices or cortical involvement due to MS may cause these findings.  相似文献   
140.
The fulminating form of subacute sclerosing panencephalitis is an extremely rare condition. Imaging findings are usually not correlated with clinical staging. We describe a 4-year-old girl with severe neuronal loss, demyelination, and gliosis in subcortical white matter by magnetic resonance spectroscopic examination even though she was diagnosed as clinical stage II. In 2 months' time, her clinical status worsened significantly. Follow-up magnetic resonance spectroscopy revealed findings that were consistent with clinical status. It is our opinion that magnetic resonance spectroscopy could demonstrate a rapidly progressive fulminating course of subacute sclerosing panencephalitis even in the early clinical stages.  相似文献   
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