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981.
PURPOSE: To evaluate the feasibility and accuracy of daily B-mode acquisition and targeting ultrasound-based prostate localization (BAT) and to compare it with computed tomography (CT) and electronic portal imaging (EPI) in 3-dimensional conformal radiotherapy (3-D CRT) for prostate cancer. PATIENTS AND METHODS: Ten patients were treated with 3-D CRT (72 Gy/30 fractions, 2.4 Gy/fraction, equivalent to 80 Gy/40 fractions, for alpha/beta ratio of 1.5 Gy) and daily BAT-based prostate localization. For the first 5 fractions, CT and EPI were also performed in order to compare organ-motion and set-up error, respectively. RESULTS: 287 BAT-, 50 CT- and 46 EPI-alignments were performed. The average BAT-determined misalignments in latero-lateral, antero-posterior and cranio-caudal directions were -0.9 mm+/-3.3 mm, 1.0 mm+/-4.0 mm and -0.9 mm+/-3.8 mm, respectively. The differences between BAT- and CT-determined organ-motion in latero-lateral, antero-posterior and cranio-caudal directions were 2.7 mm+/-1.9 mm, 3.9+/-2.8 mm and 3.4 +/- 3.0 mm, respectively. Weak correlation was found between BAT- and CT-determined misalignments in antero-posterior direction, while no correlation was observed in latero-lateral and cranio-caudal directions. The correlation was more significant when only data of good image-quality patients were analyzed (8 patients). CONCLUSION: BAT ensures the relative positions of target are the same during treatment and in treatment plan, however, the reliability of alignment is patient-dependent. The average BAT-determined misalignments were small, confirming the prevalence of random errors in 3-D CRT. Further study is warranted in order to establish the clinical value of BAT.  相似文献   
982.
983.
OBJECTIVE: Chronic hemodialysis may lead to losses of carnitine from plasma and muscles. The aim of the present study was a comparison of carnitine contents in different human muscles (brachioradialis muscle and rectus muscle of abdomen) and evaluation of the correlation between plasma and tissue carnitine concentrations in patients receiving hemodialysis and healthy control patients. METHODS: The studies were performed in two groups of patients receiving hemodialysis. The first group included 37 patients (18 male, 19 female) (muscle specimen was taken from the brachioradialis muscle). The second group included 28 patients (15 male, 13 female) (muscle specimen was taken from the rectus muscle of abdomen). The other two separate groups of patients without renal involvement served as the controls. RESULTS: Significantly lower free plasma and free muscle carnitine (FMC) contents were noticed in patients receiving hemodialysis in comparison with the controls. Significantly higher total muscle carnitine (TMC) and FMC concentrations in the brachioradialis muscle in comparison with the rectus muscle of abdomen were observed in both the hemodialysis and control groups. Negative correlations between TMC, FMC, and FMC/TMC ratio versus duration of hemodialysis were found. No correlations between muscle and serum carnitine levels were observed. CONCLUSIONS: Patients receiving hemodialysis are carnitine deficient. Tissue carnitine depletion is related to hemodialysis duration. Carnitine concentration in blood does not represent the whole carnitine stores in patients receiving hemodialysis. Brachioradialis muscle carnitine contents are significantly higher than those in the rectus muscle of abdomen.  相似文献   
984.
985.

Background

Laparoscopic sleeve gastrectomy (LSG) and laparoscopic gastric bypass (LRYGB) are most commonly performed bariatric procedures. Laparoscopic approach and enhanced recovery after surgery (ERAS) protocols managed to decrease length of hospital and morbidity. However, there are patients in whom, despite adherence to the protocol, the length of stay (LOS) remains longer than targeted. This study aimed to assess potential risk factors for prolonged LOS and readmissions.

Methods

The study was a prospective observation with a post-hoc analysis of bariatric patients in a tertiary referral university teaching hospital. Inclusion criteria were undergoing laparoscopic bariatric surgery. Exclusion criteria were occurrence of perioperative complications, prior bariatric procedures, and lack of necessary data. The primary endpoints were the evaluations of risk factors for prolonged LOS and readmissions.

Results

Median LOS was 3 (2–4) days. LOS > 3 days occurred in 145 (29.47%) patients, 79 after LSG (25.82%) and 66 after LRYGB (35.48%; p = 0.008). Factors significantly prolonging LOS were low oral fluid intake, high intravenous volume of fluids administered on POD0, and every additional 50 km distance from habitual residence to bariatric center. The risk of hospital readmission rises with occurrence of intraoperative adverse events and low oral fluid intake on the day of surgery on.

Conclusions

Risk factors for prolonged LOS are low oral fluid intake, high intravenous volume of fluids administered on POD0, and every additional 50 km distance from habitual residence. Risk factors for hospital readmission are intraoperative adverse events and low oral fluid intake on the day of surgery.
  相似文献   
986.
The mean arginase activity in breast cancers (n = 80) was significantly higher than in control tissues and it accounted for 0.31 +/- 0.23 U/g wet tissue and 0.083 +/- 0.061 U/g (P < 0.05), respectively. With the cutoff value of 0.1 U/g wet tissue, raised arginase activity was observed in 74% of tumors. The preoperative arginase activity in blood serum from women with breast cancer was 11.2 +/- 7.9 U/l (n = 115), and it was significantly higher than in 70 healthy controls, where it was 5.7 +/- 2.4 U/l (P < 0.05). With the cutoff value for normal serum arginase activity above 8.0 U/l, the activity was raised in 10% of control individuals, and in 63% of women with breast cancer. The sensitivity and specificity of the arginase test in blood serum were 63% and 60%, respectively. Two isoforms immunologically identical to human kidney arginases (L-arginine amidinohydrolase) were found in both normal and cancerous breast tissues. The level of anionic form was similar in control and cancerous tissues, whereas the cationic isoform predominated in breast cancer. The cationic isoform was the only one present in serum of both ill and healthy women, and its level was higher in patients with breast cancer. Thus, it can be concluded that the cationic isoform is responsible for the increase of arginase activity in serum of patients with breast cancer.  相似文献   
987.
Involvement of sphingolipids in apoptin-induced cell killing.   总被引:5,自引:0,他引:5  
The potential anti-tumor agent Apoptin activates apoptosis in many human cancers and transformed cell lines, but is believed to be less potent in primary cells. Although caspase 3 is activated during apoptin-induced apoptosis, the mechanism of tumor cell killing remains elusive. We now show that apoptin-mediated cell death involves modulation of the sphingomyelin-ceramide pathway. Treating cells with Ad-GFPApoptin resulted in increased ceramide accumulation and enhanced expression of acid sphingomyelinase (ASMase) with a concomitant increase in ASMase activity and decreased sphingomyelin. Using confocal microscopy, ASMase, normally present in the endosomal/lysosomal compartment, was observed to translocate to the cell's periphery. Cotreatment of Ad-GFPApoptin-infected cells with the ASMase inhibitor desipramine (2.5 muM) attenuated (30%; P<0.01) apoptin-induced cell death. Apoptin was also able to induce a significant decline in sphingosine content by inhibition of ceramide deacylation through down-regulation of acid ceramidase at the protein level. Supporting the role of ceramide in apoptin action, treatment of cells with the combination of an exogenous cell-permeable ceramide analog (C6-ceramide) and Ad-GFPApoptin infection yielded a significant increase (P<0.01) in apoptosis over either treatment modality alone. Together, these data suggest that apoptin modulates ceramide/sphingolipid metabolism as part of its mechanism of action.  相似文献   
988.
Archivum Immunologiae et Therapiae Experimentalis - Human cathelicidin, LL-37, is small antimicrobial peptide, which reveals also some immunomodulatory and proangiogenic properties and, therefore,...  相似文献   
989.
990.
[Purpose] To evaluate the effects of balance training after arthroscopic anterior cruciate ligament reconstruction. [Subjects and Methods] Sixteen patients (mean 33 ± 8 years old) who underwent anterior cruciate ligament reconstruction three months prior to participating in a one-month rehabilitation program. The control group included 15 people aged 34 ± 4 years. Patients’ functional level was evaluated according to the Lysholm knee score, and balance quality was ascertained by static and dynamic tests. A balance platform was used to measure the center of foot pressure deflection. Two dynamic balance tests evaluated time of task execution. [Results] Lysholm knee score improved significantly after rehabilitation. Balance in the sagittal plane with eyes closed improved significantly after rehabilitation. The average velocity of center of foot pressure swing in both the frontal and sagittal planes with eyes closed differed significantly from those of controls. Execution time required for the two dynamic tests decreased significantly after rehabilitation and were significantly better than those in the controls. [Conclusion] Maintaining static balance with eyes closed is very challenging after anterior cruciate ligament reconstruction. Maintaining balance in the sagittal plane is particularly difficult. A one-month rehabilitation program partially improves static and dynamic balance.Key words: Balance training, Anterior cruciate ligament, Reconstruction  相似文献   
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