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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   
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Internal hernia, the protrusion of a viscus through a peritoneal or mesenteric aperture, is a rare cause of small bowel obstruction. We report the clinical presentation, surgical management, and outcomes of one of the largest series of nonbariatric internal hernias. Ten-year retrospective review of patients at our institution yielded 49 cases of internal hernias. Majority of patients presented with symptoms of acute (75%) or intermittent (22%) small bowel obstruction. While 16% of CT scans were suspicious for internal hernia, in no cases the preoperative diagnosis of internal hernia was made. The most frequent internal hernias were transmesenteric (57.0%) and 34 hernias (69%) were caused by previous surgery. All internal hernias were reduced and the defects were repaired. Compromised bowel was present in 22 cases and 11 patients underwent small bowel resection. The mean postoperative hospitalization was 10.9 days. The overall mortality rate from our series is 2%, and the morbidity rate is 12%. Transmesenteric hernias, as complications of previous surgeries, are the most prevalent internal hernias. Preoperative diagnosis of internal hernia is extremely difficult because of the nonspecific clinical presentation. However, if discovered promptly, internal hernias can be repaired with acceptable morbidity and mortality. Poster presentation at Digestive Disease Week, May 22, 2006, Los Angeles, California, USA.  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   
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Approximately 80% of hereditary hearing loss is non-syndromic. Non-syndromic deafness is the most genetically heterogeneous trait. The most common and severe form of hereditary hearing impairment is autosomal recessive non-syndromic hearing loss (ARNSHL), accounting for approximately 80% of cases of genetic deafness. To date, 22 genes implicated in ARNSHL have been identified. Recently a gene, DFNB31/WHRN, which encodes a putative PDZ scaffold protein called whirlin, was found to be responsible for the ARNSHL DFNB31. We found evidence for linkage to the DFNB31locus in a consanguineous Tunisian family segregating congenital profound ARNSHL. Mutation screening of DFNB31/WHRNrevealed four nonpathogenic sequence variants and a novel frameshift mutation [c.2423delG] + [c.2423delG] that changed the reading frame and induced a novel stop codon at amino acid 818 ([p.Gly808AspfsX11] + [p.Gly808AspfsX11]). To determine the contribution of the DFNB31locus in the childhood deafness, we performed linkage analysis in 62 unrelated informative families affected with ARNSHL. No linkage was found to this locus. From this study, we concluded that DFNB31/WHRN is most likely to be a rare cause of ARNSHL in the Tunisian population.  相似文献   
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Previous reports indicate that enlarged hilar and mediastinal lymph nodes caused by sarcoid-like reactions may develop after curative resection of cancer, and their presence does not necessarily denote neoplastic recurrence. Reports further suggest that coexisting pulmonary infiltrates in this setting may be related to sarcoidosis. In this study, we describe two patients who had resected lung and gastric cancer and who later developed pulmonary interstitial infiltrate, concurrent with progressive mediastinal lymphadenopathy initially thought to be caused by intrathoracic dissemination of their cancer. These changes were shown by open lung biopsy to be a benign, granulomatous reaction interpreted as sarcoidosis. Thus, it is important to recognize this clinical pattern when pulmonary infiltrates develop after complete treatment of cancer in an otherwise relapse-free patient and to encourage lung or lymph node biopsy in these particular settings in order to confirm a sarcoid-like reaction, thereby avoiding unnecessary chemotherapy for presumed tumor recurrence.  相似文献   
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Three serological tests: Immunodiffusion (ID), Counterimmunoelectrophoresis (CIEP) and Enzyme-linked immunosorbent assay (ELISA) were used to study the role of crude adult worm antigen (CAWA) of Toxocara canis and each of its purified fractions in the serodiagnosis of human toxocariasis. Sensitivities of the three tests were lower in the ocular than in the visceral group, using different antigens. Purified fraction 1 showed more sensitive and specific reactions in the three tests, compared to CAWA or purified fraction 2 (P-F2) antigen. The other purified fractions (P-F3, P-F4 and P-F5) gave no positive reactions in any of the three tests. Using P-F1 antigen, ELISA was the most sensitive technique for diagnosis of both visceral and ocular toxocariasis followed by CIEP and then ID and the difference was statistically significant. However, CIEP was the most specific test followed by ELISA and lastly ID test. The ELISA test using Excretory-Secretory (E-S) larval antigen of Toxocara canis was less sensitive than the ELISA test using P-F1, although it was 100% specific. Thus, ELISA test using P-F1 is the test of choice for diagnosis of human toxocariasis, but when the specificity of a reaction is in doubt, CIEP test using the same antigen can be of value.  相似文献   
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A real-time PCR assay developed to quantify Methanobrevibacter oralis indicated that its inoculum significantly correlated with periodontitis severity (P = 0.003), despite a nonsignificant difference in prevalence between controls (3/10) and patients (12/22) (P = 0.2, Fisher test). The M. oralis load can be used as a biomarker for periodontitis.  相似文献   
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