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71.
Noroviruses are a leading cause of epidemic and sporadic acute gastroenteritis worldwide. The development of sensitive molecular diagnostic techniques has revolutionized our understanding of norovirus epidemiology over the past two decades, but norovirus strain types associated with sporadic gastroenteritis remain poorly described. Therefore, we conducted a systematic review of studies performed after 2000 to clarify the genotypic distribution of noroviruses in children (≤18 years of age) with sporadic acute gastroenteritis. Genogroup GII norovirus was the most prevalent, accounting for 96% of all sporadic infections. GII.4 was the most prevalent genotype, accounting for 70% of the capsid genotypes and 60% of the polymerase genotypes, followed by the capsid genotype GII.3 (16%) and the polymerase genotype GII.b (14%). The most common ORF1/ORF2 inter-genotype recombinants were GII.b, GII.12, and GII.4 polymerase genotypes combined with the capsid genotype GII.3, accounting for 19% of all genotyped strains. The distribution of GII.4 variants over the last decade was dominated by successive circulation of GII.4/2002, GII.4/2004, GII.4/2006b, and GII.4/2008 with GII.4/2006b continuing to date. Genotypes GII.4 and GII.3 have predominated in children during the past decade; this is most notable in the global emergence of GII.4 variant noroviruses. As the burden of rotavirus disease decreases following the introduction of childhood immunization programs, the relative importance of norovirus in the etiology of acute childhood gastroenteritis will likely increase. In order for a successful norovirus vaccine to be developed, it should provide immunity against strains with capsid genotypes GII.4 and GII.3.  相似文献   
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Inflammatory pseudotumor of the liver is a rare benign lesion, but exploratory laparotomy and a hepatectomy are often performed unnecessarily after various misdiagnoses, including liver abscess, hepatocellular carcinoma, metastatic liver tumor, and cholangiocarcinoma. We present a case of hepatic inflammatory pseudotumor in a 17-year-old man in whom diagnosis was confirmed by liver needle biopsy under ultrasonographic tomography (UST) guidance. He had complained of fever and right hypochondralgia 2 months after being operated for appendicitis. He was admitted to our hospital because of the persistence of these symptoms and the presence of a hepatic mass lesion detected by UST. He had hepatomegaly, with tenderness; leukocytosis and elevated erythrocyte sedimentation rate and C-reactive protein level were noted. UST showed a hypoechoic mass in the liver and pre-contrast computerized tomography (CT) revealed a low-density area with an ill defined margin, which was barely enhanced by the contrast medium. On the basis of the patient's clinical symptoms and the laboratory data and imaging studies, the presence of a liver abscess was suspected and antibiotics were administered. One month after the initiation of the antibiotic therapy, UST demonstrated that the portal vein had dilated serpiginously and penetrated into the mass. As the heterogeneous appearance displayed by post-enhanced CT indicated the need for a differential diagnosis of the hepatic mass lesion to rule out hepatocellular carcinoma, percutaneous needle biopsy was performed, under UST guidance. Histopathological examination demonstrated marked infiltration of plasma cells and fibrosis, findings which were consistent with those of hepatic inflammatory pseudotumor. There was a spontaneous reduction of the hepatic pseudotumor without continuous antibiotics and this reduction was documented on follow-up UST and CT. Received: June 30, 1999 / Accepted: December 17, 1999  相似文献   
75.
Some considerations on the biology of pancreatic serous cystadenoma.   总被引:3,自引:0,他引:3  
Five cases of pancreatic serous cystadenoma were examined pathologically, and their nuclear DNA ploidy patterns were determined. Four were unifocal tumors, and one was a multifocal tumor. The four unifocal tumors were typical serous cystadenomas. However, the multifocal tumor exhibited an increased N/C ratio, irregular nuclear margins, various-sized nuclei, coarse nuclear chromatin, and neural invasion. All tumor cells were stained with antiCA19-9 but none with antiCEA. In the antiCA19-9 staining, the four unifocal tumors and the tumors of the pancreatic tail in the multifocal case were positive only on the apical membrane, whereas the tumor cells of the pancreatic head in the multifocal case were positive within the whole cytosol. The unifocal tumors were diploid with a DNA Index (DI) of 1.0 and proliferation indices (PI) from 4.9 to 20.9% with a mean of 14.4%. In the multifocal case, the tumor in the pancreatic head was aneuploid (DI = 1.9) and had a PI of 27.8%. The multifocal sites in the pancreatic body were aneuploid (DI = 1.9) with a PI of 22.4%. We suggest that the biological property of serous cystadenoma should be revisited.  相似文献   
76.
[Purpose] This study aimed to verify the usefulness of a 50-m round walking test developed as an assessment method for walking ability in the elderly. [Subjects] The subjects were 166 elderly requiring long-term care individuals (mean age, 80.5 years). [Methods] In order to evaluate the factors that had affected falls in the subjects in the previous year, we performed the 50-m round walking test, functional reach test, one-leg standing test, and 5-m walking test and measured grip strength and quadriceps strength. [Results] The 50-m round walking test was selected as a variable indicating fall risk based on the results of multiple logistic regression analysis. The cutoff value of the 50-m round walking test for determining fall risk was 0.66 m/sec. The area under the receiver operating characteristic curve was 0.64. The sensitivity of the cutoff value was 65.7%, the specificity was 63.6%, the positive predictive value was 55.0%, the negative predictive value was 73.3%, and the accuracy was 64.5%. [Conclusion] These results suggest that the 50-m round walking test is a potentially useful parameter for the determination of fall risk in the elderly requiring long-term care.Key words: 50-meter round walk test, Local elderly individuals, Falls  相似文献   
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Reduced port surgery has been attracting attention in the field of minimally invasive surgery. Although the use of SILS is becoming widespread, technical difficulty has delayed its adoption for laparoscopic liver resection. Recently, advances in laparoscopic liver resection have been made in tandem with advances in surgical skill and devices. The main driver in conventional laparoscopic liver resection's evolution to become less surgically invasive seems to be single‐incision laparoscopic liver resection (SILLR). To date, most reports on SILLR have been single case reports or case series. Only a few cohort studies on conventional laparoscopic surgery and SILLR have been conducted. Recent reports have described the use of SILLR for well‐localized lesions and solitary tumors located in the anterolateral segments of the liver or left liver lobe, but its application remains limited to partial resection and left lateral sectionectomy. The feasibility and safety of SILLR have been demonstrated, but additional work is needed for standardization of the procedure.  相似文献   
79.
Treatment strategy for Boerhaave''s syndrome   总被引:5,自引:0,他引:5  
Esophageal rupture is a potentially mortal condition. Rapid and correct diagnosis, and urgent surgical treatment with esophagectomy is indicated, but conservative and other surgical treatments have also been reported recently. The treatment strategies for esophageal rupture are discussed here, based on our experiences with four cases during the last 10 years. They were admitted urgently and each was treated by a different method. Three of them underwent emergency operations, one undergoing primary closure of the ruptured esophagus, another received a T-tube insertion from the ruptured site with omental flap, and the third an esophagogastrectomy. The fourth case was treated conservatively. All patients survived and were discharged 36-144 days post treatment. One of them was readmitted for debridement of necrotic rib. In conclusion, the prompt and accurate diagnosis of esophageal rupture is crucial for a subsequent successful treatment. Conservative treatment or operation including esophagectomy will be determined by the severity of the condition.  相似文献   
80.
This study was designed to determine the efficacy of esophagectomy preceded by the laparoscopic transhiatal approach (LTHA) with regard to the perioperative outcomes of esophageal cancer. The esophageal hiatus was opened by hand‐assisted laparoscopic surgery, and carbon dioxide was introduced into the mediastinum. Dissection of the distal esophagus was performed up to the level of the tracheal bifurcation. En bloc dissection of the posterior mediastinal lymph nodes was performed using LTHA. Next, cervical lymphadenectomy, reconstruction via a retrosternal route with a gastric tube and anastomosis from a cervical approach were performed. Finally, a small thoracotomy (around 10 cm in size) was made to extract the thoracic esophagus and allow upper mediastinal lymphadenectomy to be performed. The treatment outcomes of 27 esophageal cancer patients who underwent LTHA‐preceding esophagectomy were compared with those of 33 patients who underwent the transthoracic approach preceding esophagectomy without LTHA (thoracotomy; around 20 cm in size). The intrathoracic operative time and operative bleeding were significantly decreased by LTHA. The total operative time did not differ between the two groups, suggesting that the abdominal procedure was longer in the LTHA group. The number of resected lymph nodes did not differ between the two groups. Postoperative respiratory complications occurred in 18.5% of patients treated with LTHA and 30.3% of those treated without it. The increase in the number of peripheral white blood cells and the duration of thoracic drainage were significantly decreased by this method. Our surgical procedure provides a good surgical view of the posterior mediastinum, markedly shortens the intrathoracic operative time, and decreases the operative bleeding without increasing major postoperative complications.  相似文献   
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