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41.
The technological development in endoscopy is directed toward improved accuracy of the diagnoses of novel diseases. The capsule endoscope and balloon-assisted endoscope are examples of such technological development. By these novel technologies, the small intestine can be examined in more detail. Therefore, an increasing number of novel diseases have been discovered, requiring the establishment of diagnosis and treatment strategies for these unknown diseases. In particular, obscure gastrointestinal bleeding, Crohn’s disease, and nonsteroidal anti-inflammatory drug-induced enteropathy are of great interest to endoscopists. The capsule endoscope is the best method for screening the small intestine; however, the development of supporting methods such as the patency capsule is eagerly desired.  相似文献   
42.
The present study examined the effect of bolus viscosity on the onset of laryngeal closure (relative to hyoid elevation), the duration of laryngeal closure, and other key events of swallowing in ten healthy volunteers. All volunteers underwent 320-row area detector computed tomography swallow studies while swallowing 10 ml of honey-thick barium (5 % v/w) and thin barium (5 % v/w) in a 45° reclining position. Three-dimensional images of both consistencies were created in 29 phases at an interval of 0.10 s (100 ms) over a 2.90-s duration. The timing of the motions of the hyoid bone, soft palate, and epiglottis; the opening and closing of the laryngeal vestibule, true vocal cords (TVC), and pharyngoesophageal segment; and the bolus movement were measured and compared between the two consistencies. The result showed differing patterns of bolus movement for thin and thick liquids. With thin liquids, the bolus reached the hypopharynx earlier and stayed in the hypopharynx longer than with thick liquids. Among events of laryngeal closure, only the timing of TVC closure differed significantly between the two consistencies. With thin liquids, TVC closure started earlier and lasted longer than with thick liquids. This TVC movement could reflect a response to the faster flow of thin liquids. The results suggest that bolus viscosity alters the temporal characteristics of swallowing, especially closure of the TVC.  相似文献   
43.

Purpose

Colorectal endoscopic submucosal dissection (ESD) has not been standardized due to technical difficulties and requires extensive training for reliability. Ex vivo animal model is convenient, but has no blood flow. The objective of this study is to evaluate the characteristics of various ex vivo animal models including a blood flow model for colorectal ESD training and the usefulness of practicing endoscopic hemostasis and closure using an animal model.

Methods

Harvested porcine cecum, rectum, and stomach and bovine cecum and rectum were analyzed regarding ease of mucosal injection, degree of submucosal elevation, and status of the proper muscle layer. Ex vivo animal model with blood flow was made using the bovine cecum. The vessel around the cecum was detached, and red ink was injected. Endoscopic hemostasis for perioperative hemorrhage and endoscopic closure for perforation were performed in this model.

Results

Mucosal injection was easily performed in the bovine cecum and rectum. Submucosal elevation was low in the bovine cecum, while the proper muscle layer was not tight in the porcine rectum and bovine cecum. Endoscopic hemostasis were accomplished in six (60 %) out of ten procedures of the ex vivo blood flow model. In two non-experts, the completion rates of endoscopic closure were 40 and 60 % in the first five procedures. These rates became 100 % in the last five procedures.

Conclusions

We have evaluated the characteristics of various ex vivo animal models and shown the possibility of training for endoscopic hemostasis and endoscopic closure in the ex vivo animal model.  相似文献   
44.
Coronary artery fistulae can present late in adult life. We describe the case of a 71-year-old woman who developed a right coronary fistula, which was managed by percutaneous transbrachial coil embolization. Complete closure of the fistula was confirmed by follow-up angiography at 10 months.  相似文献   
45.
Patent ductus venosus   总被引:1,自引:0,他引:1  
BACKGROUND: Patent ductus venosus is extremely rare with only 14 cases reported in the world literature. We present a case of patent ductus venosus. METHODS AND RESULTS: A 29-year-old male was admitted with melaena stool caused by gastric haemorrhagic ulcers. Laboratory data disclosed severe anaemia; however, liver function tests were normal. Serum ammonia was also within the normal range. Serological viral markers for hepatitis B or C were all negative. The abdominal ultrasonography and computed tomography indicated a 12 mm diameter shunt located in the left lobe of the liver, which connected the portal vein with the left hepatic vein. After treatment for gastric ulcers, percutaneous transhepatic portography was performed and an enormous shunt connecting the umbilical portion of the portal vein with the left hepatic vein was revealed. CONCLUSIONS: Histological findings of the liver biopsy showed that portal venules could not be observed in the portal areas and that no fibrosis or inflammatory cell infiltration were shown. Because of the anatomical position of the shunt, the case was diagnosed as patent ductus venosus.  相似文献   
46.
The dual specificity kinases mitogen-activated protein kinase (MAPK) kinase (MKK)7 and MKK4 are the only molecules known to directly activate the stress kinases stress-activated protein kinases (SAPKs)/c-Jun N-terminal kinases (JNKs) in response to environmental or mitogenic stimuli. To examine the physiological role of MKK7 in hematopoietic cells, we used a gene targeting strategy to mutate MKK7 in murine T and B cells and non-lymphoid mast cells. Loss of MKK7 in thymocytes and mature B cells results in hyperproliferation in response to growth factor and antigen receptor stimulation and increased thymic cellularity. Mutation of mkk7 in mast cells resulted in hyperproliferation in response to the cytokines interleukin (IL)-3 and stem cell factor (SCF). SAPK/JNK activation was completely abolished in the absence of MKK7, even though expression of MKK4 was strongly upregulated in mkk7(-/-) mast cell lines, and phosphorylation of MKK4 occurred normally in response to multiple stress stimuli. Loss of MKK7 did not affect activation of extracellular signal-regulated kinase (ERK)1/2 or p38 MAPK. mkk7(-/-) mast cells display reduced expression of JunB and the cell cycle inhibitor p16INK4a and upregulation of cyclinD1. Reexpression of p16INK4a in mkk7(-/-) mast cells abrogates the hyperproliferative response. Apoptotic responses to a variety of stimuli were not affected. Thus, MKK7 is an essential and specific regulator of stress-induced SAPK/JNK activation in mast cells and MKK7 negatively regulates growth factor and antigen receptor-driven proliferation in hematopoietic cells. These results indicate that the MKK7-regulated stress signaling pathway can function as negative regulator of cell growth in multiple hematopoietic lineages.  相似文献   
47.
Background and aim: Histological changes in hepatitis C virus (HCV)‐infected patients with persistently normal alanine aminotransferase (PNALT) have not been evaluated for updated upper limits of normal (ULN; ≤19/30U/L for females/males). We assessed significant fibrosis (≥F2, METAVIR) in patients with PNALT and persistently elevated alanine aminotransferase (PEALT). Patients and methods: Nine hundred and twenty consecutive, unselected HCV patients were stratified into four groups: Group I: (n=124) PNALT within the updated ULN [0.5 × ULN (corresponding to ≤19 U/L) for females; 0.75 × ULN (corresponding to ≤30 U/L) for males]; Group II (n=173): PNALT≤1 × ULN but greater than Group I; Group III (n=313): PEALT 1–2 × ULN; and Group IV (n=310): PEALT>2 × ULN. PNALT was defined as ≥3 determinations within the normal range over ≥6 months. Results: Advanced ≥F3 and ≥F2 fibrosis increased incrementally across Groups I; II; III; and IV: 24.2 and 45.2%; 25.4 and 56.1%; 36.1 and 64.2%; and 50 and 77.1% respectively (P<0.0001 for both). Multivariable logistic regression analysis identified age [odds ratio (OR), 1.05; 95% confidence intervals (CI): 1.02–1.08; P<0.0001], alanine aminotransferase (ALT) groups (OR 1.38; 95% CI: 1.03–1.83; P=0.030), presence of moderate–severe steatosis (OR 2.70; 95% CI: 1.19–6.15; P=0.018) and ≥A2 necroinflammation (OR 17.9; 95% CI: 8.88–36.20; P<0.0001) as independent predictors of ≥F2 fibrosis. Updated ULN for ALT were better at excluding ≥F2 fibrosis compared with traditional ULN (90.6 vs. 74.2%, P=0.0041) but less specific (20.8 vs. 44%, P=0.0007) with similar positive/negative predictive values. Conclusions: HCV patients with ‘updated’ normal ALT have the lowest prevalence of significant fibrosis, although utilizing these levels without resorting to biopsy would miss significant fibrosis in almost one‐half of such patients.  相似文献   
48.

Background and Aim

The Japan Endoscopy Database (JED) Project was started to develop the world's largest endoscopic database, capture the actual performance of endoscopic practice, and standardize the terminology and fundamental items needed for a clinical and research registry. This paper presents a progress report on the first phase of this project undertaken at eight endoscopic centers in Japan.

Methods

The list of data items to be collected was drafted by the MSED‐J (Minimal Standard Endoscopic Database) subcommittee. These items were aggregated offline by integrating data from two endoscopic filing systems between July 2015 and December 2015. The study population included all patients who underwent esophagogastroduodenoscopy or colonoscopy at all eight centers, patients who underwent enteroscopy at five of the eight centers, and patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) at four of the eight centers.

Results

Data collected in this phase included 61 070 endoscopic procedures, of which 40 475 were esophagogastroduodenoscopies, 215 were enteroscopies, 19 204 were colonoscopies, and 1176 were ERCPs. Frequencies of complications were 0.68% for esophagogastroduodenoscopy, 0% for enteroscopy, 0.43% for colonoscopy, and 13.34% for ERCP. In addition, we obtained various data including Helicobacter pylori infection status, past history of endoscopy in patients who underwent enteroscopy or colonoscopy, and degree of difficulty of ERCP, although the frequencies of reporting were sometimes low, with some items <20%.

Conclusion

Results of the first phase suggest that the JED project can provide vast quantities of useful data about endoscopic procedures.  相似文献   
49.
The advent of electronic medical records brought image filing systems to many hospitals, as well as electronic endoscopic medical records. However, data integration among multiple different vendors has not yet been accomplished. We start the Japan Endoscopic Database (JED) Project endorsed by Japan Gastroenterological Endoscopy Society (JGES) from January 2015. The purposes of this project are as follows: (i) developing the world's largest endoscopic database generated from daily use of the reporting system; (ii) capturing the actual performance of endoscopic practice in Japan; and (iii) standardizing the terminology and fundamental items for registry of clinical studies. Moreover, the JED project has the potential to automatically collect data about adverse events, competency and evaluation of residents, and actual numbers of procedures on a nationwide scale, certification for the specialty board system, and so on. We believe that this design paper will be helpful not only for future nationwide research but also for international research (UMIN000016093).  相似文献   
50.
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