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71.
In living donor liver transplantation (LDLT), portal vein thrombosis (PVT) in the recipient is frequently regarded as a contraindication. To reconstruct the PV of a right-lobe liver graft (RLG) using an interposition or jump graft from the splenomesenteric junction, various vein grafts and technical modifications have been introduced. The internal jugular, external iliac, or great saphenous veins have been utilized in such reconstructive procedures. However, the superficial femoral vein (SFV) is preferable to the autologous vein grafts in terms of caliber, wall thickness, and length. We employed the recipient SFV to reconstruct PVT among 40 adult LDLT using RLG. Thirty-three were reconstructed by single end-to-end anastomosis with the right or left recipient PV. Three patients were transplanted with a RLG using 2 separated PVs reconstructed by double anastomoses with both the right and left PVs of the recipient. The remaining 4 patients required venous grafting for portal reconstruction. We used the recipient SFV as an interposition or jump graft from the splenomesenteric junction to the graft PV. There were 2 cases of anastomotic PV stenosis; 1 in portal reconstruction without a venous graft and the other with a SFV graft. Both were treated successfully by balloon angioplasty. The recipient SFV is an excellent size match for the PV reconstruction as a long interposition or jump conduit when the venous system from the deceased donor is not available. The indication for LDLT in patients with complete PVT should be carefully decided before transplantation in terms of portal reconstruction.  相似文献   
72.

Introduction

The purpose of this study was to elucidate the clinical significance of acid phosphatase in giant cell tumour of bone.

Patients and methods

Serum acid phosphatase levels were measured in 32 patients with this tumour both preoperatively and postoperatively.

Results

Serum acid phosphatase value before surgery was high in 15 patients, whereas it was within normal limits in 17 patients. The serum acid phosphatase values of all the 15 patients with high preoperative serum level fell within normal limits postoperatively. In the remaining 17 patients in whom preoperative serum acid phosphatase values were within normal limits, postoperative serum acid phosphatase levels were lower than that of preoperative ones in all the patients. In addition, there was a statistically significant positive correlation between the tumour volume and the preoperative serum acid phosphatase level.

Conclusion

It is concluded that serum acid phosphatase is a useful tumour marker for giant cell tumour of bone.  相似文献   
73.
Purpose: To assess the unique biological effects of different forms of ionizing radiation causing DNA double-strand breaks (DSBs), we compared the killing effect, mutagenesis frequency, and mutation type spectrum using the model filamentous fungus Neurospora.

Materials and methods: Asexual spores of wild-type Neurospora and two DSB repair-deficient strains [one homologous recombination- and the other non-homologous end-joining (NHEJ) pathway-deficient] were irradiated with argon (Ar)-ion beams, ferrous (Fe)-ion beams, or X-rays. Relative biological effectiveness (RBE), forward mutation frequencies at the ad-3 loci, and mutation spectra at the ad-3B gene were determined.

Results: The canonical NHEJ (cNHEJ)-deficient strain showed resistance to higher X-ray doses, while other strains showed dose-dependent sensitivity. In contrast, the killing effects of Ar-ion and Fe-ion beam irradiation were dose-dependent in all strains tested. The rank order of RBE was Ar-ion?>?Fe-ion?>?C-ion. Deletion mutations were the most common, but deletion size incremented with the increasing value of linear energy transfer (LET).

Conclusions: We found marked differences in killing effect of a cNHEJ-deficient mutant between X-ray and high-LET ion beam irradiations (Ar and Fe). The mutation spectra also differed between irradiation types. These differences may be due to the physical properties of each radiation and the repair mechanism of induced damage in Neurospora crassa. These results may guide the choice of irradiation beam to kill or mutagenize fungi for agricultural applications or further research.  相似文献   
74.

Purpose:

To assess the effect of motion artifact reduction on the diffusion‐weighted magnetic resonance imaging (DWI‐MRI) of the liver, we compared velocity‐compensated DWI (VC‐DWI) and VC‐DWI combined with tetrahedral gradients (t‐VC‐DWI) to conventional DWI (c‐DWI) in the assessment of apparent diffusion coefficients (ADCs) of the liver.

Materials and Methods:

In 12 healthy volunteers, the liver was scanned with c‐DWI, VC‐DWI, and t‐VC‐DWI sequences. The signal‐to‐noise ratio (SNR) and ADC of the liver parenchyma were measured and compared among sequences.

Results:

The image quality was visually better for t‐VC‐DWI than for the others. The SNR for t‐VC‐DWI was significantly higher than that for VC‐DWI (P < 0.05) and comparable to that for c‐DWI. ADCs in both hepatic lobes were significantly lower for t‐VC‐DWI than for c‐DWI (P < 0.01). ADC in the left lobe was significantly lower for VC‐DWI than for c‐DWI (P < 0.01). Although ADC in the left lobe was significantly higher for c‐DWI (P < 0.01), no significant differences in ADCs were found between the right and left lobes for VC‐DWI and t‐VC‐DWI.

Conclusion:

The use of a t‐VC‐DWI sequence enables us to correct ADCs of the liver for artificial elevation due to cardiac motion, with preserved SNR. J. Magn. Reson. Imaging 2013;37:172–178. © 2012 Wiley Periodicals, Inc.  相似文献   
75.

Objective

We evaluated intra- and interoperator reproducibilities in calculating the conventional indices HH15 and LHL15 from 99mTc-diethylenetriamine pentaacetic acid galactosyl human serum albumin (99mTc-GSA) scintigraphy, and proposed new, simple methods for the calculation of quantitative indices.

Methods

The results of 99mTc-GSA scintigraphy in 33 patients were retrospectively analyzed. Heart and liver ROIs were drawn manually to cover cardiac blood pool and entire liver, respectively, and HH15 and LHL15 were calculated. In addition, square regions of interest (ROIs) of fixed sizes were placed at the highest activity in blood pool and the liver. Using the square heart ROI, sHH15, an equivalent of HH15, was computed. Fractional liver uptake at 15 min (FLU15) was calculated using the square heart and liver ROIs. Intra- and interoperator reproducibilities, as well as correlation with Indocyanine green retention rate at 15 min (ICG R15), were assessed for these four indices by linear regression analysis.

Results

Substantial intra- and interoperator variabilities were found for HH15 and LHL15. The correlation coefficients for intra- and interoperator comparisons were 0.884 and 0.869 for HH15, respectively, and 0.919 and 0.917 for LHL15, respectively. The use of square ROIs instead of hand-drawn ROIs improved reproducibility. The correlation coefficients for intra- and interoperator comparisons were 0.988 and 0.973 for sHH15, respectively, and 0.989 and 0.975 for FLU15, respectively. Correlation with ICG R15 was better for sHH15 (r = 0.619) and FLU15 (r = ?0.656) than for HH15 (r = 0.439) and LHL15 (r = ?0.490).

Conclusions

HH15 and LHL15 showed substantial intra- and interoperator variabilities, and the use of square ROIs are indicated to provide better reproducibility.  相似文献   
76.
The relationship between bone mineral density in elderly women and the pattern of skeletal uptake of99mTc-HMDP, especially in regard to skull uptake, was investigated. The whole-body skeletal uptake (WBSU) and whole-body skeletal tracer distribution patterns were studied in 86 disease-free women on bone scintigraphy with99mTc-hydroxy-methylene-diphosphonate (HMDP). Bone scans were quantified by setting regions of interest (ROI) and bone mineral density (BMD) was assessed by dual-energy X-ray absorptiometry in all patients. WBSU and the skeletal distribution pattern were compared with bone mineral densities of the entire skeleton as well as selected regions. WBSU was high in the elderly and negatively correlated with regional bone mineral densities (r = ?0.403 to ?0.534). Among the regions, uptake by the skull increased with age more than in other regions in women and had the highest negative correlation with the bone mineral density. The skull uptake correlated negatively with total body BMD (r = ?0.583) and with lumbar BMD (r = ?0.561, p< 0.0001). Our results show that increased radionuclide uptake in bone scintigraphy, especially skull uptake was associated with decreased bone mineral density in elderly women, so that, increased skull uptake in elderly women would be a scintigraphic sign of post-menopausal or senile osteopenia.  相似文献   
77.
Background. This study was designed to assess the influence of coronary endothelial function and the serial changes of dual myocardial single photon emission computed tomography (SPECT) imaging in transient left ventricular (LV) apical ballooning. Methods and Results. We evaluated 35 consecutive patients (8 men and 27 women; mean age, 71 ±13 years) with transient LV apical ballooning. All patients underwent coronary angiography with acetylcholine provocation 1 month after onset. Iodine 123 β-methyl-p-iodophenyl-pentadecanoic acid (BMIPP) and thallium 201 dual myocardial SPECT was serially performed on day 1 of admission and 1 month and 6 months later. In 8 of 35 patients (23%), epicardial coronary spasm was induced by acetylcholine infusion. At the peak acetylcholine dose (100 μg), diffuse coronary vasoconstriction developed in 19 of 35 patients (54%). Of 19 patients, 13 had diffuse coronary vasoconstriction with chest pain and ST-segment depression. The total defect score of I-123 BMIPP and Tl-201 SPECT showed marked perfusion-fatty acid metabolic mismatches (13.7±3.6 vs 8.7±2.3, P<.001) at the LV apex during the acute phase but few mismatched areas (2.1±1.1 vs 1.5±1.4, P = not significant) at 6 months. Conclusions. Transient LV apical ballooning might be caused by stress-induced coronary epicardial spasm or endothelial dysfunction, resulting in myocardial stunning.  相似文献   
78.
An inducible co-stimulator (ICOS), a recently identified co-stimulatory receptor with a close structural homology of CD28 and CTLA4, is expressed on activated T cells. Anti-ICOS antibody was demonstrated to be effective on prolongation of graft survival after liver transplantation in rats. In this study, we investigated the potency of tolerance induction using the antibody combined with a recombinant adenovirus vector containing CTLA-4Ig cDNA (AdCTLA-4Ig) in rat heart transplantation model. Using a DA-to-Lewis rat heart transplantation model, an anti-rat ICOS antibody and AdCTLA-4Ig were simultaneously administered i.v. into recipients. The tissue specimens from the grafts were removed on various days after transplantation for histological evaluation. Donor-strain skin and heart grafts, and third-party heart allografts were challenged in the recipients with a long-term surviving graft. Splenocytes from the tolerance-induced recipients were used for adoptive transfer study. Anti-ICOS antibody alone did not prolong the survival of heart allograft. AdCTLA-4Ig monotherapy significantly prolonged the survival of heart allograft (Group 4). With a combination of Anti-ICOS antibody and AdCTLA-4Ig, all recipients were resulted in a long-term allograft acceptance for more than 200 days (Group 8). When challenged donor-strain skin grafts in the tolerant rats of Group 4, the skin was rejected, which also lead to a rejection of primary heart allografts. The recipients in Group 8 also rejected donor-strain skin grafts with no rejection of the primary heart grafts. These recipients accepted secondary heart grafts from donor-strain but not third-party. In Group 8 long-term survival recipients showed a high population of CD4+CD25+ regulatory T cell in peripheral blood, and in adoptive transfer study subtraction of these CD4+CD25+ T cells accelerate the rejection of heart graft in secondary irradiated recipients. The present results demonstrated that anti-ICOS antibody combined with AdCTLA-4Ig potently induces a stable immune tolerance after heart allografting in rat, which is mediated by the induction of CD4+CD25+ regulatory T cells. This strategy may be attractive for clinical employment to induce transplantation tolerance.  相似文献   
79.
A 29-year-old male with bladder cancer was referred to our hospital. Histological examination of transurethral biopsy showed transitional cell carcinoma with invasion into prostate (T4aN0M0, grade 3). Nerve-sparing radical cystectomy with ileal neobladder reconstruction was performed after 3 courses of neoadjuvant chemotherapy with Methotrexate, Epirubicin and Cisplatin. Continence and erectile function were preserved and no recurrence has been observed for 18 months after the operation. This is the sixth case of an invasive bladder cancer in Japanese patients under 30 years old.  相似文献   
80.
We describe a new technique for coronary transfer in the repair of anomalous origin of the left coronary artery from the pulmonary artery. The left coronary artery is elongated with the native pulmonary artery wall to form a spiral-shaped coronary cuff to construct an unstretched new left coronary artery system from the ascending aorta. A postoperative angiographic scan showed good flow of the left coronary artery without any kinking or narrowing. This technique is considered useful when an anomalous coronary artery arises a long way from the ascending aorta.  相似文献   
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