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991.
BK polyomavirus (BKPyV) is recognized as a pathogen that causes diseases such as hemorrhagic cystitis and nephritis after allogeneic hematopoietic stem cell transplantation (HSCT) or renal transplantation. BKPyV‐associated disease is thought to occur through reactivation under immunosuppression. However, the possibility of its nosocomial transmission and the clinical significance of such transmission have not been elucidated. During a 6‐month period, nine adult patients (median age: 47 years) who had hematological disorders and who were treated with HSCT (n = 7) or chemotherapy (n = 2) in a single hematology department developed hemorrhagic cystitis due to BKPyV infection. The polymerase chain reaction products of BKPyV DNA obtained from each patient were sequenced. Of the nine patients, six had subtype I, 2 had subtype IV, and 1 had subtype II or III. In the alignment of sequences, four and two of the six subtype I strains were completely homologous (100%). These results strongly suggest that BKPyV has the potential to cause nosocomial infection within a medical facility, especially among recipients of HSCT. Further studies are clearly warranted to elucidate the route(s) of BKPyV transmission in order to establish optimal infection control.  相似文献   
992.

Background

Routine performance of intraoperative cholangiography (IOC) during cholecystectomy is controversial. The aim of this study was to evaluate the role of IOC during cholecystectomy in addition to preoperative magnetic resonance cholangiopancreatography (MRCP) in our institution over a 12-year period.

Methods

A total of 425 consecutive patients who underwent IOC during cholecystectomy were included in this study. MRCP was performed preoperatively for bile duct evaluation in all patients. When common bile duct (CBD) stones were detected, they were removed endoscopically before the operation. We estimated the results of IOC in terms of the success rate, the detection rate of anatomic abnormality of the biliary system, and the incidence of residual CBD stones.

Results

MRCP preoperatively identified 6 (1.4?%) patients with abnormal biliary systems and 56 with CBD stones, which were endoscopically removed. The success rate of IOC was 93.8?% (399/425). Abnormalities of the biliary system were detected in 12 patients (12/399, 3.0?%) and CBD stones in 8 (8/399, 2.0?%). Of the eight patients with stones, seven had been examined by endoscopy preoperatively and found to have CBD stones. The detection rate of bile duct stones in patients with preoperative endoscopic removal of CBD stones (7/56, 12.5?%) was significantly higher than those with CBD stones first detected during IOC (1/365, 0.3?%) (p?<?0.01). Moreover, no residual CBD stones were detected in patients who were operated on within fewer than 12?days from endoscopic treatment to the operation.

Conclusions

IOC is indicated even after preoperative sphincterotomy for CBD stones. In our study, it resulted in a 12.5?% incidence of persistent stones after sphincterotomy. IOC plays an additional role in detecting CBD stones and in revealing abnormalities of the biliary tree in patients whose biliary tree was preoperatively evaluated by MRCP.  相似文献   
993.
994.
Concentrations of enolase isozymes in normal kidney and renal cell tumors in rats were determined using a highly sensitive enzyme immunoassay, and the isozymes were immunohistochemically localized in tissue sections. Levels of -enolase in renal cell turnors were significantly lower than in normal kidney, whereas those of -enolase were significantly elevated (mean ±SD:211±129 ng/mg protein, n=15, as compared to 27.1±2.9 ng/mg protein, n=7). The proportion of -enolase in the total enolases in the tumor tissues (1.6±0.5%) was significantly higher than in normal kidney (0.15±0.005). Immunohistochemistry revealed epithelial cells of all nephron segments to be positive for the -isozyme, whereas -enolase staining was strongly positive only in the loops of Henle, being faint in the distal tubules and absent in the proximal tubules. Both - and -enolases demonstrated positive immunostaining in all of the seven renal cell tumors studied. These findings indicate that an isozyme switch from - to -enolase occurs during rat kidney carcinogenesis, taking into account the derivation from proximal tubules, consistent with the findings for renal cell carcinomas in man.  相似文献   
995.
Background Idiopathic thrombocytopenic purpura (ITP) is an autoimmune disorder for which appropriate diagnostic treatments are uncertain. The response to splenectomy varies from 60% to 90%, and the remaining patients relapse and require further treatment. Therefore, it is important to predict the outcome of splenectomy before and after surgery. The objective of this study was to evaluate the efficacy of splenectomy in patients diagnosed with ITP. Materials and Methods From 1988 to 2004, we splenectomized 32 patients with ITP; 17 underwent laparoscopic splenectomy (LS) and 15 underwent conventional open splenectomy (OS). For analysis, patients were separated retrospectively into two groups: the “responding group,” those who showed good outcomes with splenectomy, and the “non-responding group,” those who did not show good outcomes with splenectomy. Blood samples were examined before and immediately after surgery (day 0) and on postoperative days (POD) 1, 3, 5, and 7. Results The median follow-up was 8.3 years (range: 1–16 years). The overall 5- and 10-year survival rates after splenectomy were 96.9% (one death). The responding group included 24 patients (75%), and the non-responding group included 7 (21.9%). Platelet counts in the responding group increased gradually until POD 7, and although platelet counts in the non-responding group were almost constant until POD 5, they subsequently decreased until POD 7. Average platelet counts in the responding and non-responding groups were 269 and 124 × 109/l on POD 7, respectively (P < 0.05). The pre- to post-surgery ratio of platelet counts were almost the same as the result of the actual data. Platelet counts during the long-term follow-up for the responding and non-responding groups were related to those noted on discharge. Conclusions A high platelet count on POD 7 was associated with a good response to splenectomy, but age at surgery, the time interval between diagnosis and splenectomy, and prior responses to corticosteroid were not. We suggest that long-term outcomes of splenectomy can easily be predicted by platelet counts on POD 7.  相似文献   
996.
K Kato  S Kondo  T Morikawa  S Okushiba  H Katoh 《Surgery》1999,126(3):577-580
BACKGROUND: Distal splenorenal shunt (DSRS) with splenopancreatic disconnection (SPD) is an ideal operation for permanent control of variceal bleeding. However, it is a very complicated procedure, and DSRS without SPD has a functional disadvantage: It gradually loses its selectivity and portal blood flow. To overcome these conditions, we designed a new technique--modified DSRS, which is easy to perform and maintains long-term selectivity of the shunt. METHODS: Modified DSRS was performed by using an external iliac vein graft without treating small pancreatic tributaries of the splenic vein. It was applied in 4 cases, and shunt patency and selectivity were examined by angiography during follow-up periods (6-76 months). RESULTS: Modified DSRS was technically more feasible and less complicated than DSRS with SPD. Every attempt was successful. There was no operative mortality, and all the patients were discharged from the hospital in good condition. The shunts were patent in all of them, and the selectivity of the shunt was maintained better in comparison to standard DSRS. CONCLUSIONS: Modified DSRS is a much easier and safer technique than standard DSRS. We consider this procedure to be the best method for surgical management of portal hypertension causing esophageal and gastric varices.  相似文献   
997.
Pathoanatomy of posterior malleolar fractures of the ankle   总被引:5,自引:0,他引:5  
BACKGROUND: The functional outcome following ankle fractures that involve a posterior malleolar fragment is often not satisfactory, and treatment of this type of fracture remains controversial. Thorough knowledge of the pathologic anatomy of the posterior malleolar fracture is essential for planning appropriate treatment. Thus, we conducted a computed tomographic study to clarify the pathologic anatomy of the posterior malleolar fracture. METHODS: Between 1999 and 2003, fifty-seven consecutive patients with a unilateral ankle fracture with one or more posterior fragments were managed at our hospital. We reviewed the patients' preoperative computed tomographic scans to determine (1) the ratio of the posterior fragment area to the total cross-sectional area of the tibial plafond and (2) the angle between the bimalleolar axis and the major fracture line of the posterior malleolus. Each fracture was categorized according to the location of the major fracture line on the computed tomographic image at the level of the tibial plafond. RESULTS: The fifty-seven fractures were categorized into three types: (1) the posterolateral-oblique type (thirty-eight fractures; 67%), (2) the medial-extension type (eleven fractures; 19%), and (3) the small-shell type (eight fractures; 14%). Two of the eleven medial-extension fractures extended to the anterior part of the medial malleolus. A total of nine of the eleven medial-extension fractures actually consisted of two fragments [corrected] The conditions are not exclusive of one another; for example, in the case of one of the fractures exhibiting two fragments, the fracture also extended to the anterior part of the medial malleolus [corrected] The average area of the fragment comprised 11.7% of the cross-sectional area of the tibial plafond for posterolateral-oblique fractures and 29.8% for medial-extension fractures. In the cases of seven of the nine fractures that comprised >25% of the tibial plafond, the fracture line extended to the medial malleolus. The angles between the bimalleolar axis and the major fracture line of the posterior malleolus varied. CONCLUSIONS: The fracture lines associated with posterior malleolar fractures appear to be highly variable. A large fragment extending to the medial malleolus existed in almost 20% of the posterior malleolar fractures in the current study, and some fragments involved almost the entire medial malleolus. Because of the great variation in fracture configurations, preoperative use of computed tomography may be justified. The information obtained from this study will be helpful for conducting basic research of this condition and for determining appropriate surgical approaches.  相似文献   
998.

Introduction

Breast cancer incidence increases from the age of 30 years. As this age range coincides with that in which women usually pursue pregnancy, undergoing medical examinations for conditions such as breast cancer is a concern, especially when pregnancy is uncertain during the first eight weeks. Moreover, in this age range, breast often exhibits a high density, thus compromising diagnosis. For such density, digital breast tomosynthesis (DBT) provides a more accurate diagnosis than 2D mammography given its higher sensitivity and specificity. However, radiation exposure increases during DBT, and it should be determined.

Methods

We determined the entrance surface dose, scattered radiation dose, and average glandular dose (AGD), which can be mutually compared following an international protocol. Using our proposed method, the distribution of scattered radiation can be easily and quickly obtained with a minor load to the equipment. Then, we can determine the indoor scattered radiation and surface dose on patients during DBT.

Results

We obtained a maximum AGD of 2.32 mGy. The scattered radiation was distributed over both sides with maximum of approximately 40 μGy, whereas the maximum dose around the eye was approximately 10 μGy.

Conclusion

By measuring doses using the proposed method, a correct dose information can be provided for patients to mitigate their concerns about radiation exposure. Although the obtained doses were low, their proper management is still required. Overall, the results from this study can help to enhance dose management for patients and safety management regarding indoor radiation.  相似文献   
999.
PURPOSE: Surgery for gastrointestinal stromal tumors (GIST) of the stomach is now frequently performed using a laparoscopic approach. We investigated the feasibility and effectiveness of laparoscopy in the management of GIST of the stomach. METHODS: We reviewed the records of 12 consecutive patients who underwent laparoscopic surgery for GIST between April 2000 and April 2004, and compared their short-term outcomes with those of patients who underwent open surgery. All laparoscopic wedge resections were done using stapling devices and 3-4 trocars, often with the aid of intraoperative gastroscopy. We examined all patients preoperatively using various diagnostic modalities, including endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA). A laparoscopic approach was not indicated if the tumor was located near the cardia or pylorus or if it was >=5 cm in diameter. RESULTS: A specific diagnosis of GIST was obtained preoperatively by EUS-FNA in 10 of the 12 patients. The median diameter of the lesion was 2.7 cm (range, 1.5-4.8 cm). Although intraoperative complications were encountered in two patients, conversion to open surgery was not required, and we were able to perform complete tumor excision with negative surgical margins in all patients. The median operative time was 100 min (range, 65-180 min), similar to that for open surgery. First flatus was passed earlier, and the interval to resuming oral intake was shorter than after open surgery. No major postoperative complications such as leakage developed, and the median postoperative hospital stay was 7 days (range, 5-12 days). All diagnoses made by EUS-FNA were confirmed by immunohisto-pathological evaluation of resected specimens. CONCLUSION: Laparoscopic wedge resection is a feasible treatment option for GISTs of the stomach if the lesion is <5 cm in diameter.  相似文献   
1000.
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