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71.
Recent advances in highly conformal radiotherapies greatly extend the indications for radiotherapy of liver tumors. However, because of poor tolerance to hepatic radiation, estimation of the intensity of irradiation of the liver is important, particularly for a cirrhotic liver. Knowledge of radiation-induced hepatitis is important for understanding how to optimize hepatic radiation therapy. Pathological changes of the irradiated liver, which include perivenular fibrosis, sinusoidal obstruction, and damage to Kupffer cells and hepatocytes, can be visualized using clinical imaging techniques. This review article discusses and illustrates the pathological and radiological changes of hepatic tumors and the surrounding parenchyma of the irradiated liver.  相似文献   
72.

Purpose

We investigated whether hilar radioaerosol deposition affects the clearance rate of technetium-99m-labeled diethylenetriaminepentaacetic acid (99mTc-DTPA) from peripheral alveolar regions.

Materials and methods

A total of 38 patients underwent 99mTc-DTPA inhalation lung scintigraphy. Six region of interest (ROI) patterns were adopted: ROI 1 was outlined around the entire hemithorax, and ROIs 2–6 were outlined around the hemithorax but excluded square ROIs of different size in the hilar region. Half-times (T½) were calculated with time-activity curves using onecompartment and two-compartment analyses. The T½ of ROIs 1–5 were plotted against the T½ of ROI 6, and regression lines were obtained with the least-squares method. The absolute values of the differences between surveyed values and regression line were calculated. The Wilcoxon test for trend and a single linear regression model were used to determine statistical significance.

Results

There were significant reductions in the absolute values of the differences between surveyed values and regression line from ROIs 1–5 by one-component analysis and the fast component of two-compartment analysis (P < 0.001).

Conclusion

Our results suggest that the deposition of radioaerosol in the hilar region affects the clearance rate of 99mTc-DTPA from the alveoli in damaged lungs. The hilar region should be excluded from ROIs when alveolar epithelial permeability is evaluated.
  相似文献   
73.

Background

A retrospective analysis indicated that the incidence of delayed gastric emptying (DGE) was less after using a circular stapler (CS) for duodenojejunostomy than that after hand-sewn (HS) anastomosis in pylorus-preserving pancreaticoduodenectomy (PpPD). This randomized clinical trial compared the incidence of DGE postoperative after CS duodenojejunostomy with that of conventional HS anastomosis in PpPD.

Methods

We randomly assigned 101 patients (age 20–80) undergoing PpPD to receive CS duodenojejunostomy (group CS, n?=?50) or HS duodenojejunostomy (group HS, n?=?51) in two Japanese cancer center hospitals between 2011 and 2013. The patients were stratified by institution and size of the main pancreatic duct (<3 or ≥3 mm). The primary endpoint was the incidence of grade B or C DGE according to the international definition with a non-inferiority margin of 5 %. This trial is registered with University hospital Medical Information Network (UMIN) Center: UMIN000005463.

Results

Per-protocol analysis of data on 95 patients showed that grade B or C DGE was found in 4 (8.9 %) of 45 patients who underwent CS anastomosis and in 8 (16 %) of 50 patients who underwent HS anastomosis (P?=?0.015). There were no differences in the overall incidence of DGE (P?=?0.98), passage of the contrast medium through the anastomosis (P?=?0.55), or hospital stays (P?=?0.22).

Conclusions

CS duodenojejunostomy is not inferior to HS anastomosis with respect to the incidence of clinically significant DGE, justifying its use as treatment option.
  相似文献   
74.
Alveolar echinococcosis is a parasitosis endemic to red fox habitats in the northern hemisphere. The liver is the most commonly affected organ, followed by the lungs. We report the case of an elderly woman with hepatic alveolar echinococcosis (HAE) complicated by a hepatopulmonary fistula. We performed a one-stage operation for the hepatic and pulmonary lesions through the transdiaphragmatic route via a laparotomy. We report this case to emphasize that the first-line treatment for a hepatopulmonary fistula caused by HAE should be radical surgery, which results in relief of symptoms and a good outcome.  相似文献   
75.
Curative liver resection is technically challenging when multiple liver metastases from colon cancer involve the confluence of the three major hepatic veins. We report two cases of successful extended left hemihepatectomy achieved by severing all of the major hepatic veins together with the wall of the inferior vena cava, to resect liver metastases from colon cancer. Reconstruction of the right hepatic vein was done after unroofing the right anterior area of the liver with a direct anastomosis of the right hepatic vein. We did not need to perform total vascular exclusion or portovenous shunting during the liver transection. This simple and safe method can increase the surgical indications for previously unresectable tumors.  相似文献   
76.
PURPOSE: Anhydrobiotic organisms are known to have an extremely high tolerance against a range of stresses. However, the functional role of anhydrobiosis in radiation tolerance is poorly understood, especially in development following irradiation. The present study aims to evaluate effects of anhydrobiosis on radiation tolerance in an anhydrobiotic insect, Polypedilum vanderplanki. MATERIALS AND METHODS: Larval survival (48 h), anhydrobiotic ability, metamorphosis and reproduction after exposure to 1-9000 Gy of gamma-rays at the larval stage were compared between anhydrobiotic (dry) and normal (wet) phases. RESULTS: Wet larvae were killed in a dose-dependent manner at doses higher than 2000 Gy, and all died within 8 h after 4000 Gy exposure. In contrast, dry larvae survived even 5000 Gy, and some of them still tolerated 7000 Gy and were alive at 48 h after rehydration. Moreover, greater radiotolerance of dry larva, compared to wet ones, was demonstrated in terms of metamorphoses. However, anhydrobiosis did not protect against radiation damage in terms of producing viable offspring. CONCLUSION: These results indicate that anhydrobiosis enhances radiotolerance, resulting in increases of successful metamorphoses.  相似文献   
77.
PURPOSE: Anhydrobiotic larvae of Polypedilum vanderplanki are known to show an extremely high tolerance against a range of stresses. We have recently reported that this insect withstands exposure to high doses of gamma-rays (linear energy transfer [LET] 0.2 keV/microm). However, its tolerance against high LET radiation remains unknown. The aim of this study is to characterize the tolerance to high-LET radiations of P. vanderplanki. MATERIALS AND METHODS: Larval survival and subsequent metamorphoses were compared between anhydrobiotic (dry) and non-anhydrobiotic (wet) samples after exposure to 1 - 7000 Gy of three types of heavy ions delivered from the azimuthally varying field (AVF) cyclotron with LET values ranging from 16.2 - 321 keV/microm. The tolerance against 4He ions was also compared among three chironomid species. RESULTS: At all LET values measured, dry larvae consistently showed greater radiation tolerance than hydrated larvae, perhaps due to the presence of high concentrations of the disaccharide trehalose in anhydrobiotic animals, and the radiation-induced damage became evident at lower doses as development progressed. Relative biological effectiveness (RBE) values based on the median inhibitory doses reached a maximum at 116 keV/microm (12C), and the maximum RBE clearly increased as development progressed. Lower D0 (dose to reduce survival from relative value 1.00 - 0.37 on the exponential part of the survival curve), and higher Dq (quasi-threshold dose) were found in individuals exposed to 4He ions, compared to gamma-rays, and in P. vanderplanki larvae compared to non-anhydrobiotic chironomids. CONCLUSION: Anhydrobiosis potentiates radiation tolerance in terms of larval survival, pupation and adult emergence of P. vanderplanki exposed to high-LET radiations as well as to low-LET radiation. P. vanderplanki larvae might have more efficient DNA damage repair after radiation than other chironomid species.  相似文献   
78.
HYPOTHESIS: While simultaneous resection has been shown to be safe and effective in patients with synchronous metastasis, neoadjuvant chemotherapy followed by hepatectomy has gradually gained acceptance for both initially nonresectable metastasis and resectable metastasis. The boundary between these treatments is becoming unclear. We hypothesized that factors associated with colorectal cancer may play an important role in the prognosis of patients with synchronous metastasis and may be useful for identifying patients who can be expected to have adequate results following simultaneous resection. DESIGN: Outcome study. SETTING: Tertiary referral center. PATIENTS: From January 1980 to December 2002, 187 patients underwent curative resection for synchronous liver metastasis from colorectal cancer. One hundred forty-two patients received simultaneous resection, 18 underwent staged resection, and 27 underwent delayed hepatic resection. Twenty-one clinicopathological factors were analyzed, and long-term prognosis was assessed. MAIN OUTCOME MEASURES: Prognostic factors and patient survival. RESULTS: There was no in-hospital death. In a multivariate analysis, the factors that significantly affected the prognosis of synchronous metastasis were 4 or more lymph node metastases around the primary cancer (P<.001) and multiple liver metastases (P = .003). In patients with 3 or fewer lymph node metastases around the primary cancer, the 5-year survival rates of those with 1, 2 to 3, and 4 or more liver metastases were 63%, 33%, and 40%, respectively, but these rates were 15%, 22%, and 0%, respectively, in patients with 4 or more lymph node metastases around the primary cancer. CONCLUSIONS: The results support the application of simultaneous resection in patients with 0 to 3 colorectal lymph node metastases. However, in patients with 4 or more colorectal lymph node metastases, biological selection by neoadjuvant chemotherapy may be more suitable.  相似文献   
79.
80.

Background  

Postoperative pancreatic fistula (POPF) remains a leading cause of morbidity after pancreaticoduodenectomy (PD). In the present study we sought to establish a preoperative scoring system with which to predict this complication.  相似文献   
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