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81.
It is generally accepted that the three semicircular canals are set at right angles to each other and the lateral semicircular canal is smaller than the anterior and posterior semicircular canals. Precise knowledge of the size and spatial relationships of the semicircular canals is vital, and so the 40 petrous parts of the temporal bones were scanned by micro‐CT at a slice thickness of 35 µm. The micro‐CT images were used in reconstructing three‐dimensional models of the bony labyrinth using computer software. Various dimensions of the semicircular canals were measured using the software, and statistical analysis was performed. The anterior semicircular canal was slightly wider than the posterior semicircular canal, and their heights were similar. The radius of curvature of the lateral semicircular canal was 20% smaller than those of the anterior and posterior semicircular canals. The angles between the three canals were not exactly 90 degrees: they were 92.1, 84.4, and 86.2 degrees between the anterior and posterior, anterior and lateral, and posterior and lateral semicircular canals, respectively. We obtained high‐resolution images of the semicircular canals using three‐dimensional reconstruction software, and these were used to precisely measure the angles between the semicircular canals and the area of the distorted circle formed by each semicircular canal. Anat Rec, 296:834–839, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
82.
Apolipoprotein (apo) E mutants are associated with type III hyperlipoproteinemia characterized by high cholesterol and triglycerides levels. Autosomal dominant hypercholesterolemia (ADH), due to the mutations in the LDLR, APOB, or PCSK9 genes, is characterized by an isolated elevation of cholesterol due to the high levels of low‐density lipoproteins (LDLs). We now report an exceptionally large family including 14 members with ADH. Through genome‐wide mapping, analysis of regional/functional candidate genes, and whole exome sequencing, we identified a mutation in the APOE gene, c.500_502delTCC/p.Leu167del, previously reported associated with sea‐blue histiocytosis and familial combined hyperlipidemia. We confirmed the involvement of the APOE p.Leu167del in ADH, with (1) a predicted destabilization of an alpha‐helix in the binding domain, (2) a decreased apo E level in LDLs, and (3) a decreased catabolism of LDLs. Our results show that mutations in the APOE gene can be associated with bona fide ADH.  相似文献   
83.
84.
The origin of methicillin-resistant Staphylococcus aureus (MRSA) strains from otolaryngology outpatients has not been evaluated yet in Korea. We analyzed epidemiologic and genetic characteristics of MRSA isolates from the ear discharge of 64 outpatients with chronic otitis media in a Korean University Hospital during 2004. MRSA strains were grouped as either from the initial visit (n=33) or the follow-up visit (n=31) based on the timing of isolation. Healthcare-associated risk factors were frequently present among patients of the initial visit group, especially prior visit to primary clinic (79%) and antibiotic use (73%). SCCmec typing and multilocus sequence typing results showed that two genotypes, ST5-MRSA-II and ST239-MRSAIII, were prevalent in both the initial visit (73% vs. 24%) and the follow-up visit (55% vs. 42%). Pulsed-field gel electrophoresis identified eight types, including two major types shared by both groups. We conclude that majority of MRSA strains from ear discharge of chronic otitis media belonged to nosocomial clones that might be circulating in the community. This is the first report of the genetic analysis of MRSA strains from otolaryngology practices in Korea.  相似文献   
85.
OBJECTIVE: We analyze the factors related to progression to AIDS or death in HIV-infected patients from the Proyecto para la Informatización del Seguimiento Clínico epidemiológico de los pacientes con Infección por VIH/SIDA (PISCIS) Cohort and we assess the optimal time to initiate highly active antiretroviral therapy (HAART) taking lead time into account. METHODS: We selected naive patients who were AIDS-free and initiated HAART after January 1998. Statistical analyses were performed using Cox proportional hazards models. Lead time was defined as the time it took the deferred group with an early disease stage to reach the later stage. The analysis accounting for lead time was performed using multiple imputation methods based on estimates from the pre-HAART period as described elsewhere. RESULTS: Multivariate analysis on 2035 patients (median follow-up = 34.3 months) showed significantly higher hazard ratios (HRs) for a CD4 count <200 cells/microL (HR = 3.79, 95% confidence interval [CI]: 2.18 to 6.57), HIV-1 RNA level >100,000 copies/mL (HR = 1.84, 95% CI: 1.26 to 2.69), and hepatitis C virus (HCV) coinfection (HR = 2.40, 95% CI: 1.65 to 3.49), whereas a lower risk was found for those who started HAART between January 2001 and June 2004 (HR = 0.55, 95% CI: 0.30 to 0.90). When lead time and unseen events were included, we found a higher risk of progression to AIDS among patients who deferred treatment when the CD4 count reached <200 cells/microL (HR = 2.97, 95% CI: 1.91 to 4.63) and 200 to 350 cells/microL (HR = 1.85, 95% CI: 1.03 to 3.33) compared with those who started treatment with CD4 counts from 200 to 350 cells/microL and >350 cells/microL, respectively. CONCLUSIONS: Advanced HIV disease, HCV coinfection, and early HAART period were determinants of AIDS progression or death. Lead-time analysis in asymptomatic HIV-infected patients suggests that the best time to start HAART is before the CD4 count falls to lower than 350 cells/microL.  相似文献   
86.

Purpose

To retrospectively determine whether the hyperintense hepatocellular carcinomas (HCCs) seen on the hepatobiliary phase of gadoxetic acid-enhanced MR imaging (EOB-MRI) might have different histologic characteristics from usual hypointense HCCs.

Materials and methods

Two hundred three surgically proven HCCs from 192 patients who underwent preoperative EOB-MRI were analyzed. The demographic and histologic characteristics of hyperintense HCCs were compared with usual hypointense HCCs by using the t-test or Fisher's exact test.

Results

By visual assessment, 18 (8.8%) tumors were classified as hyperintense HCCs. Patients with hyperintense HCC were significantly (p < 0.05) older (60.1 vs. 55.2 years) than those with hypointense HCCs. Hyperintense HCCs showed significantly lower rate of microvascular invasion (27.8% vs. 53.5%) and significantly higher rate of peliosis (61.1% vs. 30.8%). Hyperintense HCCs were more frequently expanding type, and none showed infiltrative type or scirrhous histologic pattern.

Conclusions

Hyperintense HCCs seem to have clinical and histologic features that might be related with more favorable outcomes.  相似文献   
87.
In order to assess the effectiveness of the thermal biofeedback training combined with the progressive muscle relaxation therapy in the treatment of patients with essential hypertension, blood pressure decline was measured on the treatment group who had the combined thermal biofeedback and progressive muscle relaxation training (N=11), and on the control group who had only the progressive muscle relaxation training (N=8). Baseline blood pressure was measured four times for two weeks on both groups. For the treatment group, blood pressure was measured twice before and after each of eight sessions of thermal biofeedback training for four weeks. For the control group, blood pressure was measured every two visits to a clinic for progressive muscle relaxation self-training twice before and after the self-training. A significant decline of the systolic blood pressure by 20.6 mmHg and of the diastolic blood pressure by 14.4 mmhg was observed in the treatment group. There was a tendency for both blood pressures to increase in the control group.  相似文献   
88.
AIMS: Minimal change disease (MCD) is the most common primary nephrotic syndrome in children. Some suggested that interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-alpha) are involved in the pathogenesis of MCD. This study was done to see changes of plasma and urinary IL-8, TNF-alpha, and their effects on determination of permeability of glomerular basement membrane (BM) contributed by heparan sulfate proteoglycan (HSPG). METHODS: Study patients consisted of 19 biopsy-proven MCD children aged 2-15 years old. Both plasma, urinary IL-8 and TNF-alpha were measured. Employing the Millicell system, IL-8 and TNF-alpha were screened for the permeability factors. We examined whether IL-8 and TNF-alpha regulated BM HSPG gene expression and HS synthesis in the glomerular epithelial cells (GECs). RESULTS: Urinary IL-8 during relapse was significantly increased when compared with that of during remission or controls (13,996 +/- 2,811 vs. 2,941 +/- 373, 5,331 +/- 640 ng/mg.cr) (p < 0.05). Urinary TNF-alpha during relapse was also significantly increased (364.4 +/- 51.2 vs. 155.3 +/- 20.8, 36.0 +/- 4.5 ng/mg.cr) (p < 0.05). Plasma IL-8 during relapse was significantly increased compared to that during remission(1.19 +/- 0.62 vs. 0.51 +/- 0.42 ng/ml) (p < 0.05). However, the negative results were obtained in the permeability assay using the Millicell system. No difference was seen in BM HSPG gene expression and HS synthesis in the GECs. CONCLUSION: Therefore, it seems that both IL-8 and TNF-alpha may not play a disease-specific role in the pathogenesis of MCD.  相似文献   
89.
PURPOSE: We compared the results of hand assisted laparoscopic and conventional open radical nephrectomy. MATERIALS AND METHODS: Clinical data on 54 hand assisted and 50 open radical nephrectomies performed at our hospital from September 1999 to October 2002 were reviewed. RESULTS: Mean operative time in the laparoscopic and open groups was similar (194.9 and 180.7 minutes, respectively, p = 0.087). However, estimated mean blood loss (182.8 vs 262.8 ml, p <0.001), mean days to oral intake (2.6 vs 3.7 days, p <0.001) mean duration of an indwelling drain (2.6 vs 3.2 days, p <0.001) and mean hospital stay (6.8 vs 8.9 days, p <0.001) were significantly less in the laparoscopic group. In the laparoscopic group no conversions or re-explorations were required and no major complications occurred. CONCLUSIONS: Our findings suggest that hand assisted laparoscopic radical nephrectomy represents an effective, minimally invasive treatment option in patients with suspected renal cell carcinoma.  相似文献   
90.
Gu JH  Jeong SH 《Microsurgery》2012,32(2):148-152
Reconstruction of complex defects resulting from radical resection of venous malformation occurring in other digits except the thumb is challenging because a thin and durable flap is required to achieve optimal reconstruction without functional impairment. Here, we describe an alternative reconstruction technique in a young patient. A 15-year-old female patient with venous malformation of the left 3rd finger was treated by radical excision of the tumor including involved skin, distal phalanx, and nail bed followed by reconstruction with free medial plantar artery perforator flap and split thickness nail bed graft from the great toe. Twenty-nine months after surgery, the reconstructed finger showed a acceptable aesthetic result without tumor recurrence and excellent restoration of motor function. This method can be considered as an useful alternative option for management of the digital venous malformation in other digits except the thumb. Indications and technical aspects of this method are discussed in this report.  相似文献   
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