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1.
PURPOSE: To determine whether 3-dimensional ultrasonography (3D US) provides information about anatomy and position of extraocular muscles to better guide surgeons approaching strabismus in patients with craniosynostosis who often have anomalous or absent eye muscles. METHODS: The 4 rectus eye muscles were imaged using 3D US for 7 children with craniosynostosis before or after strabismus surgery. Reconstructed 3D images were interpreted as having normal or abnormal anatomy and position, based on comparison with images acquired from 6 normal eyes. Interpretation was validated against the intraoperative findings from strabismus surgery. RESULTS: A total of 34 scans from the study group were used for comparison and validation purposes. Accuracy of anatomical assessments was 85% +/- 12% (percentage +/- confidence interval) and of positional assessments was 62% +/- 16%. Sensitivity and specificity of anatomical assessments was 80% +/- 14% and 88% +/- 10%, respectively. Anatomic anomalies detected by 3D US included excessively thick, thin, scarred and fibrotic, and absent muscles. Sensitivity and specificity of positional assessments was 48% +/- 17% and 85% +/- 12%, respectively. Positional anomalies such as muscle displacement off the normal clock hour axis or posteriorly displaced insertion were also detected. CONCLUSIONS: The 3D US may have an adjunctive role in determining anatomy and position of rectus muscles in patients with craniosynostosis, although it was more accurate in assessing anatomic features rather than positional features of rectus muscles.  相似文献   
2.
BACKGROUND AND OBJECTIVES: To evaluate the experience with laparoscopic nephrectomy in a large county hospital and perform a cost comparison between uncomplicated open and laparoscopic nephrectomy. METHODS: Eleven consecutive patients who underwent an uncomplicated laparoscopic nephrectomy in a large county hospital were compared with 8 patients who underwent uncomplicated open nephrectomy during the same period. Patient charts and corresponding billing records were reviewed to determine overall hospitalization cost and individual cost components. RESULTS: No perioperative complications occurred in either the laparoscopic or open group, and no statistically significant differences existed between groups with regard to patient demographics or operative parameters. The overall operating room costs favored the open nephrectomy group by dollars 1070 (P=0.003). However, the overall cost of hospitalization, surgeon professional fees, duration of hospitalization, room and board costs, laboratory, and radiology costs, pharmacy costs, intravenous solution and infusion pump costs all significantly favored the laparoscopic patient group. The mean difference in overall hospital cost between laparoscopic and open nephrectomy was dollars 1211 in favor of laparoscopy (P=0.037). CONCLUSIONS: Our experience with laparoscopic nephrectomy in a large county hospital demonstrates a clear economic advantage in favor of the laparoscopic approach. Given limited funding for public hospitals and a clear patient benefit, laparoscopic nephrectomy should constitute first-line therapy when nephrectomy is indicated.  相似文献   
3.
The purpose of our study was to prospectively evaluate the striatal uptake of 123I-labeled N-(3-fluoropropyl)-2beta-carbomethoxy-3beta-(4-iodophenyl)nortropane (FP-CIT) and the response to l-dopa therapy in patients with cerebrovascular disease (CVD) who develop clinical symptoms of vascular parkinsonism (VP). METHODS: Twenty consecutive patients who developed VP in the course of CVD were prospectively enrolled in the study. All patients had CT evidence of CVD (17 patients had lacunar infarcts, 3 patients had territorial strokes). The clinical stage of the patients was assessed using the Hoehn and Yahr scale, and the severity of the symptoms was measured using the Unified Parkinson's Disease Rating Scale score. Ten age-matched subjects were used as controls. SPECT was performed 180 min after injection of 185 MBq 123I-FP-CIT using a dual-head gamma-camera. The ratio of the mean specific-to-nonspecific striatal binding for the entire striatum, caudate, and putamen was calculated in all patients and compared with that of controls. Putamen-to-caudate binding ratios were compared as well. The response to therapy was compared between patients with normal and abnormal 123I-FP-CIT binding. RESULTS: No correlation was found between any of the clinical variables and response to therapy in patients with VP. Nine patients had normal striatal 123I-FP-CIT binding with no significant differences in striatal or subregional binding ratios compared with those of the controls. In contrast, 11 patients had significantly diminished striatal binding compared with that of controls (P < 0.001). Subanalyses showed significantly decreased binding in the caudate (P < 0.04 and P < 0.01 for the right and left caudate, respectively), diminished binding in the putamen (P < 0.04 and P < 0.01 for the right and left putamen, respectively), and a decreased putamen-to-caudate ratio on the right side (P < 0.001). The latter ratio was not significant on the left. Two of the 3 patients with territorial strokes had significantly diminished striatal 123I-FP-CIT binding in the hemisphere contralateral to the CT lesion. All 9 patients with normal scan findings had a poor response to L-dopa. Six of 11 patients with abnormal studies had no response to L-dopa, whereas 5 patients had a good response (P < 0.03). CONCLUSION: The diagnosis of VP cannot be accurately confirmed on the basis of clinical features alone because CVD may alter the typical presentation of PD. Functional imaging with 123I-FP-CIT is highly recommended in patients with CVD who develop symptoms of VP to confirm or exclude the existence of nigrostriatal dopaminergic degeneration. Identifying a subset of patients with reduced 123I-FP-CIT binding in the striatum is important for better treatment selection.  相似文献   
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The whole-cell patch-clamp technique was used to study the effects of holding potential and frequency on the Ca2+ current in frog ventricular myocytes. INa was blocked by TTX, and ica was activated with depolarizing clamps from different holding potentials. Variation of the holding potential revealed three new effects on ica: (1) At -40 mV iCa declined with a time constant of 15 min, while at -90 mV, this irreversible decline (run down) in iCa did not occur. (2) The decline of iCa at -40 mV was biphasic: run down was preceeded by a slow inactivation with a time constant of 40 s, which was reversible upon returning the holding potential to -90 mV. (3) Increasing the frequency of the clamp pulses from 0.1 to 1 Hz led to a rapid decline of iCa when the holding potential was positive to -60 mV, but at -90 mV had either no effect or increased iCa by 35%, if c-AMP was included in the dialyzing solution. On the other hand, c-AMP did not alter the time course of the run down and the slow inactivation. Replacement of extracellular Ca2+ by Ba2+ markedly slowed iCa kinetics, but did not change the very slow inactivation or the frequency-induced enhancement of iCa. Injection of c-AMP led to a transient increase of iCa. The phosphodiesterase inhibitor theophylline enhanced the amplitude of the transient and slowed its decay. This effect was mimicked by increased frequency. It is concluded that frequency-induced enhancement of iCa is highly dependent on the holding potential, independent of Ca2+, and may involve elevation of the intracellular level of c-AMP via inhibition of phosphodiesterase activity. The new type of very slow inactivation is probably under direct voltage control and independent of Ca2+ and c-AMP.  相似文献   
7.
If fulminate rejection in allogeneic and xenogeneic engraftments is not an evolutionary relict feature, then any treatment that ablates the host surveillance's effector arms capabilities and eliminates graft vs. host reactivity should induce donor chimerism in transplant settings. We demonstrate here marked proliferative response of Botryllus (Urochordata) blood cells months following their infusions (2×104–105 blood cells per host) into the concordant xenogeneic environment of irradiated Botrylloides soma. The state of infused cells was followed by Botryllus specific microsatellite alleles on DNA samples from host zooids and vascular system. Increased growth rates and life spans of engrafted hosts in some cases, and sudden chimerical death following the outbreak of donor cells in others, indicate a ‘double-edged sword’ expression of concurrent evolutionary selected mechanisms. This DES phenomenon in immunity underlies divergent stem cell competition phenomena in multicellular organisms, leading in mammals, to cases of autoimmune diseases vis-à-vis long-lasting microchimerism events following an iatrogenic transplantation.  相似文献   
8.
Summary The purpose of this study was to determine the effect of caffeine ingestion on physical performance after prolonged endurance exercise. Twenty three trained male volunteers participated in a 40-km march and were divided into two groups, matched for caffeine clearance rate and aerobic capacity. The experimental group ingested, prior to the march, a caffeinated drink at a dose of 5 mg·kg−1 body mass and at the 3rd and 5th h of marching an additional drink at a dose of 2.5 mg·kg−1 body mass. The control group ingested a drink of equal volume at the same times. Upon termination of the march each subject performed a cycle ergometer test at an intensity of 90% maximal oxygen consumption. Time to exhaustion and rate of perceived exertion (RPE) were recorded. Blood samples were drawn predrink, at the 3rd and 5th h of marching and immediately after the cycle ergometer test, and were analysed for caffeine, free fatty acids (FFA), lactate and glucose levels. Plasma FFA levels increased during the march (p<0.05), with no significant difference between groups. Lactate levels increased in the experimental group (p<0.05), with no significant change in the control group. Glucose levels did not change significantly in either group. After the cycle ergometer test, lactate levels were significantly higher in the experimental, as compared to the control group (3.77±0.33 vs 2.52±0.35 mmol·l−1, respectively). There was no significant difference between treatments in the time to exhaustion on the cycle ergometer, but RPE was different (p<0.05). Under the conditions of this study, the results do not indicate caffeine ingestion as an ergogenic aid which will postpone exhaustion following prolonged endurance exercise. This work was presented, in part, at the Canadian Association of Sports Sciences Annual Meeting, October 1987, Lake Louise, Alberta, Canada  相似文献   
9.
Peripheral neuropathy (PN) can be a manifestation of various neurological, infectious, metabolic, autoimmune, rheumatic, and malignant diseases. During the past decade, intravenous immunoglobulin (IVIg) has been increasingly used in the therapy of PN. Compared with other immunomodulatory therapies, IVIg has an excellent safety profile. IVIg is used today as a first-line therapy in the treatment of Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy, and multifocal motor neuropathy. Some small studies and reports of clinical cases presented in this article found benefit from IVIg in treating PN associated with diabetes, paraproteinemia, HIV, multisystem rheumatic diseases, and paraneoplastic PN. No clear recommendations can be made relating the use of IVIg in these conditions. Prospective, randomized trials are required to clarify this issue.  相似文献   
10.
Type III 3-methylglutaconic aciduria (MGA) (MIM 258501) consists of early bilateral optic atrophy, later development of spasticity, extrapyramidal dysfunction and occasionally cognitive deficits, and urinary excretion of 3-methylglutaconic acid and 3-methylglutaric acid. The presence of the disorder in an Iraqi-Jewish genetic isolate led to mapping of the OPA3 gene to chromosome 19q13.2-q13.3, followed by isolation of the gene itself. OPA3 consists of two exons and codes for a peptide of 179 amino acids. Iraqi-Jewish patients with type III MGA are homozygous for a splice site founder mutation in OPA3 (IVS1-1G>C) which abolishes mRNA expression in fibroblasts. Here we report a novel mutation in OPA3 (320-337del) in a Kurdish-Turkish patient with optic atrophy and 3-methylglutaconic and 3-methylglutaric aciduria, previously carrying the diagnosis of type IV MGA. We conclude that type III MGA occurs in patients of non-Iraqi-Jewish ancestry, and should be considered in patients with type IV MGA that have optic atrophy and ataxia.  相似文献   
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