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71.
Dialysis-related spondyloarthropathy (DRS) is a severe complication of long-term hemodialysis that ultimately leads to functional disability of the upper and lower extremities. Although the cause of this disease is still unknown, it is thought that amyloid deposits are involved. 2-Microglobulin (2M) is a major component of amyloid fibrils, some of which are modified with the advanced glycation end-product (AGE). To clarify the pathophysiology of DRS we histologically examined the ligamentum flavum of the cervical spine in 15 patients with DRS. The mean duration of hemodialysis was 20 years (12–27 years). In addition to the congo red stain for amyloid, 2M and AGE were detected by immunohistochemical methods. Macrophages were stained with CD68 antibody. Amyloid deposits were found in tissues, although the extent of the stained area differed among the patients. Part of the amyloid deposit area was positively immunostained for 2M and AGE. In 10 cases macrophages positive for CD68 infiltrated around the amyloid deposits. Comparing these histological findings with the dialysis duration, more positive staining areas for 2M and AGE were found in the tissue from patients with long-term dialysis. These findings suggest that both 2M and AGE play roles in the pathogenesis of DRS.  相似文献   
72.
The value of inversion-recovery (IR) sequences in the diagnosis and staging of prostatic carcinoma with magnetic resonance (MR) imaging was studied. Twenty-six patients with carcinoma of the prostate were imaged at 1.5 T with an endorectal surface coil and with a variety of IR sequences and a set of spin-echo (SE) sequences for comparison. Ex vivo prostate specimens were imaged again at the same field strength. The two images were correlated with histologic sections. Cancer was identified with MR imaging in 96% of patients. Of the tumors more than 4 mm in diameter, 87% were identified on T2-weighted SE images, whereas only 26% were identified on IR images. However, IR images may be more useful in local staging of carcinoma. Gross capsular infiltration was present in only two patients; however, it was detectable (and excluded in five other patients) by means of IR images. It was not detectable on SE images. The high quality of images obtained with the endorectal coil was confirmed. The authors conclude that addition of the IR sequence to MR imaging with the endorectal coil may improve the usefulness of this examination.  相似文献   
73.
In the sequence of spin echo MRI systems, RF power selects the output value from which the signal intensity of the whole photography volume changes to the maximum as a 90-degree pulse in auto tuning during prescanning by the SIGNA HORIZON LX 1.0 Tesla ver. 8.3. When it consists of two or more organizations like a human body, although the RF power to which signal intensity serves as the maximum is in agreement with the RF power of a 90-degree pulse if it is a uniform phantom, the RF power from which signal intensity reaches the maximum differs for every organization. When we determined RF power by the signal intensity of two or more whole organizations in this experiment, it was found that RF power was strongly influenced by a high signal organization. Moreover, if CNR in two or more organizations is considered, T(1) contrast will be emphasized for the direction of an angle less than 90 degrees. It was possible for the same effect to be acquired by lowering the power of the RF pulse and emphasizing T(1) contrast.  相似文献   
74.
OBJECTIVE: The authors' goal was to determine whether FDG uptakes in various regions of the brain are different for early and late scanning time in positron emission tomography (PET). METHOD: F-18 fluorodeoxyglucose (FDG) PET was performed on 15 healthy normal subjects to obtain early and late acquisition glucose metabolic images (30 and 60 min after FDG injection), respectively. The two sets of images were compared in a voxel-by-voxel analysis. RESULTS: In the bilateral posterior cingulate gyrus, parietal and frontal association cortices, and subcallosal cortices, the FDG uptakes were larger on the late scan image than on the early scan image, and the FDG uptakes were larger in the cerebellar hemisphere, vermis and frontal basis on the early scan image than on the late scan image. CONCLUSIONS: These results suggest that there are different regional FDG uptakes depending on the scanning time after FDG injection and we must be careful in replacing conventional FDG PET scanning with early scanning in FDG PET study.  相似文献   
75.
BACKGROUND: Infection is a constant threat for the living-donor liver transplantation (LDLT) recipients, although little information is available on the occurrence of infection in such patients. METHODS: One hundred and thirteen consecutive LDLT recipients were prospectively followed for the presence of surgical site infections (SSIs) defined by CDC from April 2001 to March 2002. Risk factors for SSIs were evaluated by univariate and multivariate analysis. RESULTS: Of the 113 LDLT recipients, 42 (37%) developed 57 episodes of SSIs (21 intraabdominal abscess, 20 peritonitis, 8 cholangitis, and 9 wound). Of the 57 episodes, 29 (51%) had secondary bacteremia in 19 patients. Causative pathogens, including 17 episodes of polymicrobial infections, were 37 gram-positive cocci (17 Staphylococcus aureus, 16 Enterococcus spp., and 4 others), 40 gram-negative rods (25 Enterobacteriaceae, 13 Pseudomonas aeruginosa, and 4 others), and 2 Candida albicans. Univariate analysis revealed that ABO incompatibility and repeat surgery were associated with the development of SSIs. Also, univariate analysis revealed that adult recipients, ABO incompatibility, total operation duration, repeat surgery, and NNIS risk index were associated with secondary bacteremia. Multivariate analysis revealed that ABO incompatibility (OR: 14.0; 95% CI, 2.52-77.2) and repeat surgery (OR: 9.29; 95% CI, 2.00-43.1) were independently associated with secondary bacteremia. Eleven of the 42 cases (26%) who developed SSIs died. Of these 11 cases, 5 (45%) developed secondary bacteremia within 30 days before death. CONCLUSION: SSIs occurred in 37% of LDLT recipients. ABO incompatibility and repeat surgery increased the risk of developing SSIs with secondary bacteremia, which correlated with poor prognosis.  相似文献   
76.
Extensive evidence shows that a core neurobiological mechanism of autism spectrum disorder (ASD) involves aberrant neural connectivity. Recent advances in the investigation of brain signal variability have yielded important information about neural network mechanisms. That information has been applied fruitfully to the assessment of aging and mental disorders. Multiscale entropy (MSE) analysis can characterize the complexity inherent in brain signal dynamics over multiple temporal scales in the dynamics of neural networks. For this investigation, we sought to characterize the magnetoencephalography (MEG) signal variability during free watching of videos without sound using MSE in 43 children with ASD and 72 typically developing controls (TD), emphasizing early childhood to older childhood: a critical period of neural network maturation. Results revealed an age‐related increase of brain signal variability in a specific timescale in TD children, whereas atypical age‐related alteration was observed in the ASD group. Additionally, enhanced brain signal variability was observed in children with ASD, and was confirmed particularly for younger children. In the ASD group, symptom severity was associated region‐specifically and timescale‐specifically with reduced brain signal variability. These results agree well with a recently reported theory of increased brain signal variability during development and aberrant neural connectivity in ASD, especially during early childhood. Results of this study suggest that MSE analytic method might serve as a useful approach for characterizing neurophysiological mechanisms of typical‐developing and its alterations in ASD through the detection of MEG signal variability at multiple timescales. Hum Brain Mapp 37:1038–1050, 2016. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc .  相似文献   
77.

Purpose

Gastrointestinal stromal tumors (GISTs) should be surgically resected, even those smaller than 5?cm in size, which is the threshold of clinical malignancy for submucosal tumors (SMTs) in the gastrointestinal tract. This study reviewed the use of laparoscopic surgery for gastric partial resection of GISTs or SMTs that were suspected to be GISTs.

Methods

Eighteen patients underwent laparoscopic partial resection of the stomach for GISTs or SMTs. The tumor location was confirmed by intraluminal endoscopy. One-half of the circumference around the tumor was dissected, and the tumor was turned toward the abdominal cavity. The nonresected part of the tumor and the edge of the incision line was lifted up using forceps, and the incision line was closed using laparoscopic stapling devices.

Results

Two cases were diagnosed as GIST by endoscopic biopsy. Six patients underwent endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) examinations, which diagnosed five GISTs. There were 18 tumors smaller than 5?cm, including 10 GISTs, 4 leiomyomas, 3 schwannomas, and one heterotopic pancreas.

Conclusions

Endoscopic ultrasound-guided FNAB is recommended for definite preoperative diagnosis of histopathologically unknown SMTs to determine the indications for surgery. The laparoscopic approach with the assistance of endoscopy is useful for improving the curability, with minimal invasiveness for the partial resection of GISTs.  相似文献   
78.

Background

Endoscopic ultrasound (EUS)-guided drainage is widely used to manage pancreatic pseudocysts. Several studies have reported the use of EUS-guided drainage for pancreatic fistula and stasis of pancreatic juice caused by stricture of the pancreatic duct after pancreatic resection.

Methods

At the authors’ hospital, 262 patients underwent surgery involving pancreatic resection from April 2005 to March 2010. In 90 of these patients (34%), a grade B or C postoperative pancreatic fistula developed that required additional treatment. The authors performed EUS-guided transmural drainage (EUS-TD) for six patients (2.1%) with a pancreatic fistula or dilation of the main pancreatic duct visible by EUS. Percutaneous drainage was provided for 18 patients (6.8%). The success rates for EUS-TD and percutaneous drainage were compared in a retrospective analysis.

Results

In all six cases, EUS-TD was performed successfully without complications. Five of the six patients were successfully treated with only one trial of EUS-TD. The final technical success rate was 100% for both EUS-TD and percutaneous drainage. Both the short- and long-term clinical success rates for EUS-TD were 100% and those for percutaneous drainage were 61.1 and 83%, respectively. The differences in these rates were not significant (short-term success, P?=?0.091 vs. long-term success, P?=?0.403). However, the time to clinical success was significantly shorter with EUS-TD (5.8?days) than with percutaneous drainage (30.4?days; P?=?0.0013) in the current series.

Conclusions

The EUS-TD approach appears to be a safe and technically feasible alternative to percutaneous drainage and may be considered as first-line therapy for pancreatic fistulas visible by EUS.  相似文献   
79.

Purpose

Cultural views are purported to be critical barriers to the use of epidural anesthesia during childbirth in Japan, even though it is not routinely available. We sought to understand the importance of the asserted cultural barriers for Japanese women living in Michigan in the United States where access to epidural anesthesia is routine.

Methods

We used a mixed-methods approach including self-administered, cross-sectional mail surveys and semi-structured qualitative interviews. Participants were Japanese women who received prenatal care at the University of Michigan Japanese Family Health Program.

Results

Of 78 participants in the mail survey, 63% used epidural anesthesia. Positive influences to have epidural anesthesia came from friends (58%), husbands (42%), and knowledge of the epidural anesthesia experiences of others (50%). Seventeen respondents participated in qualitative interviews. Most had learned little about epidural anesthesia while living in Japan, and some respondents had heard unsettling rumors. Many mentioned obtaining their first detailed knowledge about epidural anesthesia from friends in the United States, and expressed fear or concerns about the side effects of anesthesia. Thirteen out of fourteen interviewed participants who used or wanted epidural anesthesia expressed a desire to use it for the next childbirth.

Conclusions

While Japanese women in this United States setting considered previously reported cultural barriers to epidural anesthesia for birth pain, many chose to have it during their labor. This finding implicates limited access as a barrier at least as important as cultural barriers to epidural anesthesia use in Japan.  相似文献   
80.
Jimbo S  Kobayashi T  Aono K  Atsuta Y  Matsuno T 《Spine》2012,37(20):1763-1770
STUDY DESIGN.: A 12-year prospective study of pre-existing and de novo degenerative lumbar scoliosis (DLS) among community-based female volunteers. OBJECTIVE.: To investigate serial entire spine radiographs of healthy female volunteers and to clarify radiographical characteristics and predictors of pre-existing and de novo DLS. SUMMARY OF BACKGROUND DATA.: DLS is among the most frequent spinal defomities in the aging spine; however, the onset or the natural course of this condition has not been elucidated. METHODS.: A total of 144 female volunteers were recruited from population register. Radiographical measurements using entire spine radiographs included thoracic kyphosis (T4-12), lumbar lordosis (LL) (L1-5), sacral inclination angle, pelvic incidence, sagittal balance (C7 plumb), coronal L4 endplate angle (L4 tilt), and scoliotic angle by Cobb method. More than 10° of scoliosis was diagnosed as DLS. L4 vertebral size was measured (divided by body height) as well as lateral osteophyte formation and lateral disc wedge angle. RESULTS.: Mean baseline age and follow-up period were 54.4 years and 12.1 years, respectively. Pre-existing DLS (pre-DLS) was found in 42 subjects (29.2%) at baseline. Among pre-DLS, 11 subjects (26%) showed more than 5° progression in scoliosis. De novo DLS has developed in 30 subjects (29.4%) among those without baseline scoliosis.Cox proportional hazards models revealed younger age, smaller L4 size, lower LL, greater DLS angle, and L4 tilt at baseline to be the risk factors of progression of pre-DLS and smaller L4 size, unilateral osteophyte formation, and lateral disc wedging to the risk of development of de novo DLS. CONCLUSION.: This study indicated that younger age, smaller L4 size, lower LL, greater DLS angle, and L4 tilt at baseline should be evaluated as predictors of progression of pre-DLS. Early signs of asymmetric disc degeneration and smaller L4 size should also be evaluated as predictors of development of de novo DLS.  相似文献   
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