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The feasibility of ventilation imaging with hyperpolarized (HP) 129Xe MRI has been investigated for quantitative and regional assessment of ventilation in spontaneously breathing mice. The multiple breath ventilation imaging technique was modified to the protocol of spontaneous inhalation of HP 129Xe delivered continuously from a 129Xe polarizer. A series of 129Xe ventilation images was obtained by varying the number of breaths before the 129Xe lung imaging. The fractional ventilation, r, was successfully evaluated for spontaneously breathing mice. An attempt was made to detect ventilation dysfunction in the emphysematous mouse lung induced by intratracheal administration of porcine pancreatic elastase (PPE). As a result, the distribution of fractional ventilation could be visualized by the r map. Significant dysfunction of ventilation was quantitatively identified in the PPE‐treated group. The whole‐lung r value of 0.34 ± 0.01 for control mice (N = 4) was significantly reduced, to 0.25 ± 0.07, in PPE‐treated mice (N = 4) (p = 0.038). This study is the first application of multiple breath ventilation imaging to spontaneously breathing mice, and shows that this methodology is sensitive to differences in the pulmonary ventilation. This methodology is expected to improve simplicity as well as noninvasiveness when assessing regional ventilation in small rodents. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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Background

Controversy continues as to whether single-incision laparoscopic cholecystectomy, with the somewhat larger incision at the umbilicus, may lead to a worse postoperative quality of life and more pain compared with the more classic 4-port laparoscopic cholecystectomy. The aim of this study was to compare single-incision and 4-port laparoscopic cholecystectomy from the perspective of quality of life.

Methods

This study was a multicenter, parallel-group, open-label, randomized clinical trial. A total of 120 patients who were scheduled to undergo elective cholecystectomy were randomly assigned 1:1 into the single-incision laparoscopic cholecystectomy or the 4-port laparoscopic cholecystectomy group and then assessed continuously for 2 weeks during the postoperative period. The primary outcome was quality of life, defined as the time to resume normal daily activities. Postoperative pain was also assessed. To explore the heterogeneity of treatment effects, we assessed the interactions of sex, age, and working status on recovery time.

Results

A total of 58 patients in the single-incision group and 53 in the 4-port group (n?=?111, 47 male, mean age 57 years) were analyzed. The mean time to resume daily activities was 10.2 days and 8.8 days, respectively, for single-incision and 4-port laparoscopic cholecystectomy (95% confidence interval –0.4 to 3.2, P?=?.12). Similarly, the time to relief from postoperative pain did not differ significantly between the groups. Statistically insignificant but qualitative interactions were noted; in the subgroups of women, full-time workers, and patients younger than 60 years, recovery tended to be slower after single-incision laparoscopic cholecystectomy.

Conclusion

Postoperative quality of life did not differ substantially between single-incision laparoscopic cholecystectomy and 4-port laparoscopic cholecystectomy. Patients younger than 60 years, women, and full-time workers tended to have a somewhat slower recovery after single-incision laparoscopic cholecystectomy.  相似文献   
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Hidroacanthoma simplex (HAS) is a rare benign eccrine adnexal tumor. HAS is sometimes clinically or pathologically misdiagnosed as squamous cell carcinoma in situ (Bowen's disease; BD), seborrheic keratosis (SK) or other adnexal tumor. To date, there has never been a report focusing on dermoscopic features to distinguish HAS from BD and SK. We found the following dermoscopic findings to be characteristic of HAS: fine black dots/globules (75% of cases) and fine scales arranged annularly (100% of cases). In contrast, glomerular vessels, which are typically observed in BD, were not seen in any of the four cases. Cerebriform appearance and milia‐like cysts, which are typically observed in SK, were also not seen in any of the four cases. The existence of “scattered fine black dots/globules” and “fine scales arranged annularly”, and the absence of the glomerular vessels, may contribute to precise diagnosis of HAS. Even though HAS resembles BD or SK clinically, it can be distinguished from these by the characteristic dermoscopic features.  相似文献   
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One diagnostic criterion for metabolic syndrome is obesity from the accumulation of visceral fat; others include abdominal circumference and area of visceral fat as measured by computed tomography (CT) at the umbilical level. We evaluated visceral fat using frequency-selective excitation magnetic resonance (MR) imaging SPAIR (spectral attenuation with inversion recovery) water suppression THRIVE (3D T1-high resolution isotropic volume examination). Fifty of 70 slices with 2-mm interval were used to render and measure volume of visceral fat ranging within 10 cm of the umbilicus; the area of visceral fat at the umbilical level was also measured. Imaging was completed using breath hold within 14 s. Image processing was easier than using CT.  相似文献   
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From April 1989 to December 2004, we performed liver biopsy on 475 patients and obtained biopsy proven 35 cases of non-alcoholic fatty liver. Among them, 18 cases were diagnosed as non-alcoholic steatohepatitis (NASH). During the last three years, we have tried to detect NASH using ultrasonography and elevated value of serum ferritin (> 300 ng/ml). All of the eligible 7 cases biopsied during the course were diagnosed as NASH. In these 7 cases, ALT levels improved after the body weight loss accompanied by the parallel decrease of serum ferritin levels. Measurement of serum ferritin is useful in the detection of NASH but the normal value of ferritin cannot rule out the possibility of NASH.  相似文献   
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