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1.
Intraductal papillary mucinous tumor (IPMT) of the pancreas is characterized by slow growth and a relatively favorable prognosis, however, invasive cancer originating in an IPMT is associated with a poor prognosis. Although various parameters in imaging modalities have been advocated to differentiate between benign IPMN and malignant ones, it is not easy to obtain definite diagnosis based on these parameters. Peroral pancreatoscopy (POPS) allows a clear and direct visualization of the pancreatic duct, providing useful information regarding tumor nature in IPMT. The authors have studied the usefulness of POPS in the diagnosis of IPMT. Nevertheless, its usefulness is not necessarily widely accepted and the significance of POPS is still controversial. In this review, the authors intended to address the diagnostic value of POPS and to clarify its role in the diagnosis of IPMT. The authors think treatment of IPMT can be improved by introducing POPS because the determination of surgical procedure as well as the area of resection based on the preoperative diagnosis of the involvement of the main pancreatic duct and branch duct is inevitable.  相似文献   
2.
In floating hip injuries, the priority of the steps in fixation has not been well described. We have treated these patients in accordance with the following protocols. In patients with pelvic ring fractures, the external fixation should be performed first, and in patients with acetabular fractures, the femoral fractures should be internally fixated first. The purpose of the present study was to review our experience with these fracture treatments to evaluate our strategy. For 8 years, 31 patients with femoral fractures associated with ipsilateral fractures: 26 unstable pelvic ring fractures and 7 unstable acetabular fractures were surgically treated at our level 1 trauma center. We reviewed the admission, operation, and follow-up records retrospectively and evaluated the order of the fixation and the complications. Two patients with acetabular fractures failed to follow our protocol outlined at the preoperative planning stage. There were no surgical difficulties other than two patients with the hemipelvis dislocated proximally who required traction of the fixated femur. The complications that were thought to be related to our protocol were one fat embolism syndrome and one pubic fracture displacement. One heterotopic ossification seemed to occur due to using a single approach for both fractures. We believe our protocol to be generally effective, however, in patients with acetabular and vertical shear type pelvic ring fractures, the internal or external fixation of the femur should be performed before the internal fixation of the pelvis.  相似文献   
3.
5-Fluorouracil (5-FU) in combination with leucovorin (LV) is nowadays the standard treatment in colon cancer and would be a candidate to be delivered orally to the colon. Eudragit P-4135F or Eudragit RS100 were used separately to prepare microspheres by an oil/oil emulsification process trapping 5-FU and LV simultaneously. Scanning electron microscopy permitted a structural analysis, process parameters were analyzed and drug loading and release profiles were recorded. Particle size varied between 123 (RS100) and 146 microm (P-4135F). Generally, higher encapsulation rates were found with RS100 (5-FU, 60.3+/-9.7%; LV, 81.4+/-8.6%) compared to P-4135F (5-FU, 48.3+/-2.0%; LV, 55.4+/-2.7%). Microparticles made from Eudragit RS100 released the incorporated drug combination within 8 h not exhibiting general differences between the kinetics of both drugs. P-4135F was found to maintain the undesired 5-FU release at pH 6.8 lower than 25% within 4 h while at pH 7.4, a nearly immediate release (within 15 min) was observed. Although the release was similar at pH 7.4, at pH 6.8 LV showed a distinct initial drug loss of about 60% and a complete release within 2 h. SEM analyses revealed a substantial presence of LV crystals on the particle surface provoking a distinct burst effect of LV. These observations were concluded to be related to the high lipophilicity of P-4135F provoking a separation between P-4135F and LV during the preparation process.  相似文献   
4.
BACKGROUND: Although it is clear that dissemination via the blood system involves angiogenesis, it is uncertain whether tumors also induce lymphangiogenesis or simply invade existing peritumoral vessels. The purpose of this study was to elucidate changes in tumor blood and lymph vessels in cases involving the invasion of squamous cell carcinoma in the oral cavity, and its significance. Blood and lymph vessels densities in tongue carcinomas induced in hamsters were investigated. METHODS: Tongue cancer was induced by abrading the right margin of the tongue of each hamster with an endodontic barbed broach and subsequently applying 1.0% 9,10-dimenthl-1,2-benzanthracene (DMBA) dissolved in acetone, three times a week, at the same site. Fresh frozen sections were prepared and blood vessels stained blue by perfusion with Coomassie Brilliant Blue and lymph vessels stained brown for 5'-nucleotidase. The effects on the blood vessels and lymph vessels were observed. RESULTS: The results showed that blood and lymph vessel densities were greater in the advanced carcinoma tissues than in normal tissue. These were compared in terms of the mode of cancer invasion. As tumor invasion progressed, the blood vessel density decreased but lymph vessel density tended to be higher in high-degree tumor invasion than in low-degree tumor invasion. The expression of vascular endothelial growth factor-C was seen more frequently as tumor invasion progressed. CONCLUSIONS: The present findings indicated that angiogenesis and lymphangiogenesis are affected by cancerous invasion.  相似文献   
5.
Background Cardiopulmonary bypass (CPB) may contribute to the complications and it is assumed that eliminating cardiopulmonary bypass has the potential of reducing post operative morbidity after coronary artery bypass grafting (CABG). The study was carried out to compare mortality and morbidity in the off-pump and on-pump CABG groups. Methods We prospectively analysed 200 patients undergoing CABG. Group A consists of 100 patients underwent multi-vessel off-pump CABG and group B consists of 100 patients underwent CABG with CPB. The incidence of complications (mortality, re-exploration for bleeding, myocardial infarction, atrial fibrillation, neurological events, new onset renal failure (s. creatinine>1.6 mg/dL) pulmonary complications, length of ICU stay and hospital stay were recorded, analysed and compared. Results OPCAB patients received 2.73±0.61 grafts/patient and on-pump CABG patients received 3.39±0.75 grafts/patient (p value<0.00001). There was no significant statistical difference in mortality, incidence of stroke between OPCAB and CABG with CPB patients. Length of ICU stay was 32.84±4.22 vs 44.85±7.18 hrs (p value<0.00001) and hospital stay was 6.52±0.69 vs 7.94±0.92 days (p value<0.00001) between group A and group B respectively. Incidence of atrial fibrillation was less in OPCAB group 7% vs 12% although it was statistically not significant (p value 0.33). It was observed in our study that there was no significant deference in worsening of existing renal failure between on-pump CABG and OPCAB 6% vs 2% (P value 0.28). Blood utilization was significantly less in OPCAB group (p value<0.001). Conclusion There was no statistically significant difference in terms of mortality, incidence of stroke and new onset renal failure in both groups. But there was lesser incidence of post operative atrial fibrillation, worsening of existing renal failure in off-pump group though statistically not significant. There was significant reduction in blood utilization, length of ICU and hospital stay in OPCAB group.  相似文献   
6.
The nitric oxide synthase (NOS) gene is thought to be associated with essential hypertension (EH), because NO is implicated in endothelium-mediated vasodilation. We investigated the possible association between the alleles of simple tandem repeat DNA polymorphism of the endothelial constitutive NOS (cNOS) gene and EH in Japanese subjects. In all, 100 patients with EH and 123 subjects with normal blood pressure were studied. Polymerase chain reaction was used to amplify the CA repeat site in the endothelial cNOS gene and alleles based on the CA repeat number were determined. The allele frequencies in the hypertensive group and normotensive group were then compared. Twenty-three alleles were identified in this study of Japanese subjects. The overall distributions of allele frequencies in the two groups were not significantly different. However, comparing the allele frequencies in the EH group without left ventricular hypertrophy (LVH) and the normotensive group, the overall distributions were significantly different (p = 0.019). The 33-repeat allele was found more frequently in the EH group without LVH than in the normotensive group (p = 0.000047, Odds ratio = 3.71). In conclusion, the 33-repeat allele of the endothelial cNOS gene is associated with EH without LVH, and may be a genetic marker of EH in Japanese subjects.  相似文献   
7.
Antithrombin III (AT III) is known to be the most important inhibitor of serine protease in the coagulation system. In the presence of heparin, AT III is converted from its progressive activity state to an immediate activity state. In disseminated intravascular coagulation (DIC) in the field of obstetrics, the treatment has to be initiated very early. Heparin treatment, on the other hand, is critical since frequently postpartal or postoperative wound bleeding is present. We, therefore, established diagnostic criteria for the early diagnosis of DIC and investigated the clinical efficacy of a therapy with AT III in a well-controlled comparative study versus the injectable synthetic protease inhibitor FOY. The results of the trial showed that the AT III group (92%; n = 24) was significantly (p less than 0.001) superior in clinical efficacy to the FOY group (60%; n = 15). No side effects whatsoever were observed after treatment with AT III concentrate (Behring Institute). From these results, it could be concluded that a single therapy with AT III concentrate can sufficiently control the symptoms of DIC in the field of obstetrics without the risk of increased bleeding.  相似文献   
8.
OBJECTIVE: This article reports a case of bilateral cleft lip and alveolus (BCLA) for which excessive rapid palatal expansion with a Latham appliance was performed for preoperative alignment of the protruded premaxilla. Postoperative changes of maxillary width were investigated with serial plaster casts. PATIENT AND RESULTS: A 3-month-old girl presented with complete BCLA in which the premaxilla was markedly protruded. Preoperative alignment of the protruded premaxilla with a Latham appliance was planned to facilitate primary lip repair. The appliance was placed when the patient was 4.5 months old. The necessary palatal expansion was estimated to be 7.0 mm in order to move the premaxilla backward into the ideal position. After palatal expansion and posterior repositioning of the protruded premaxilla, the primary operation, including cheiloplasty and gingivoperiosteoplasty, was performed when the patient was 7 months old. Excessive maxillary expansion might be a cause of transverse maxillomandibular discrepancy. Measurement with serial plaster casts demonstrated that maxillary widths increased from 42.3 mm pretreatment to 49.0 mm after orthopedic treatment but relapsed markedly to 43.5 mm at 3 months after the primary operation. Therefore, the net change of maxillary widths was only 1.2 mm. After alignment of the protruded premaxilla, tension-free soft tissue repairs were performed, and a harmonious alveolar arch was obtained without change in maxillary width. CONCLUSION: These results indicate that this method is useful for preoperative management of BCLA with protruded premaxilla.  相似文献   
9.
The risk of cerebral infarction (CI) in an individual is dependent on the interplay between genetic risk factors and environmental influences. Binding of thromboxane A2 (TXA2) to its receptor (TP) modulates thrombosis/hemostasis and plays a significant role in the pathogenesis of CI. The aim of the present study was to investigate the relationship between human TP gene single nucleotide polymorphisms (SNPs) and haplotypes and CI in a Japanese population. A genetic association study was performed in 194 CI patients and 365 non-CI subjects by specifically characterizing 6 SNPs in the human TP gene (rs2271875, rs768963, rs2238634, rs11085026, rs4523 and rs4806942). Analysis demonstrated that there were significant differences in the overall distribution of genotypes and dominant or recessive models of rs2271875 and rs768963 between the CI and the non-CI groups. Multiple logistic regression analysis revealed that the C allele of rs768963 was significantly associated with CI (p = 0.029), even after adjusting for confounding factors (odds ratio: 2.41). Further, the C-T-C haplotype of rs768963-rs2238634-rs4806942 was significantly more frequent in the CI group (23.0%) than in the non-CI group (17.7%). These results suggest that specific SNPs and haplotypes may have utility as genetic markers for the risk of CI and that TP or a neighboring gene is associated with the increased susceptibility to CI.  相似文献   
10.
The purpose of this study was to analyze the management of individual patients with unruptured intracranial aneurysms (UN-ANs) using a decision-analytic approach. Transition probabilities among Glasgow Outcome Scale (GOS) categories were estimated from the published literature and data from patients who had been treated at Kitasato University Hospital. Utilities were obtained from 140 health providers based principally on the GOS. Baseline analysis for a healthy 40-year-old man with an anterior UN-AN less than 10 mm in diameter showed that the quality-adjusted life expectancies for preventive operation and follow-up were 15.34 and 14.66 years, respectively. For a follow-up strategy to be preferred, the annual rupture rate had to be as low as 0.9%. These results were sustained through extensive sensitivity analysis. The results support preventive operation for UN-ANs, and identify problems that can be clarified with a well-designed stratified clinical trial.  相似文献   
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