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61.

Background  

The usefulness of laparoscopic low anterior resection for middle and lower rectal cancer remains controversial.  相似文献   
62.

Background

Laparoscopic surgery has been reported to be one of the approaches for total mesorectal excision (TME) in rectal cancer surgery. Intersphincteric resection (ISR) has been reported as a promising method for sphincter-preserving operation in selected patients with very low rectal cancer.

Methods

From July 2005 to December 2008, 35 patients with very low rectal cancer underwent laparoscopic TME with ISR. The results were compared retrospectively with those of previous open TME with ISR.

Results

Conversion to open surgery was necessary in one (3%) patient. The median operation time was 293 min and median estimated blood loss was 40 ml. The pelvic plexus was completely preserved in 32 patients. There was no mortality. Postoperative complications occurred in three (9%) patients. The median length of postoperative hospital stay was 17 days. Macroscopic complete mesorectal excision was achieved in all cases. Complete resection (R0) was achieved in 34 patients. Clinical lymph node stage, operation time, and blood loss were significantly different between the laparoscopic group and open group, but the differences of other factors were not statistically significant.

Conclusions

Laparoscopic TME with ISR is technically feasible and a safe alternative to laparotomy with favorable short-term postoperative outcomes.  相似文献   
63.
To test the hypothesis that the disruption of fukutin protein produces the brain pathology through hypoglycosylation of alpha-dystroglycan (alpha-DG), we immunostained Fukuyama congenital muscular dystrophy (FCMD) brains with an antibody that recognizes the polysaccharide epitope of alpha-DG. Immunoreactivity of the glia-limitans along the cortical surface, as well as that of the glial endfeet around vessel walls, was preserved in the FCMD cerebrum. However, fragmentation of the immunostained glia-limitans was noted in association with parenchymal protrusion and gyral fusion. In the FCMD cerebellum, this fragmentation of alpha-DG labeling was limited to the area of micropolygyria, and immunostaining at the glia-limitans and vessel walls was comparable to that of the control brains, in structurally normal areas. In the hippocampus, neurons of the dentate gyrus and corpus ammonis were immunopositive for alpha-DG in control subjects, but this staining was markedly decreased in FCMD brains. In contrast, immunolabeling of blood vessels and the glia-limitans was preserved in this region. Fukutin antisera clearly labeled hippocampal neurons in control brains, while this labeling was decreased in FCMD brains. Thus, hypoglycosylation of alpha-DG was evident in neurons, but not in the glial cell population of FCMD brains. This suggests that the mechanism of alpha-DG glycosylation may differ between neurons and glial cells, and that a fukutin gene defect may result in functional disruption through hypoglycosylation of both neuronal and glial alpha-DG.  相似文献   
64.
This article investigated the time response of COX II induction by traction of the cauda equina assessed by a quantified RT-PCR method. Under deep GOI anesthesia, male Wistar rats were fixed in the prone position and a laminectomy of the dorsal part of the first and second sacral vertebrae was performed. Following, COX II-mRNA levels in the cervical, thoracic, lumbar, sacral, and caudal segments were measured at 2, 4, 6, and 24 h after traction by a quantified RT-PCR method. After cauda equina traction, significant levels of COX II mRNA were detected in all segments of the spinal cord examined. Maximum levels in each segment were determined 4 h after traction of the cauda equina. Particularly in the sacrocaudal segments significantly higher levels of COX II mRNA were measured 24 h after traction. These results indicate that significant induction of spinal COX II mRNA was caused by cauda equina traction and that such induction plays a regulatory role in the nociceptive pain pathway.  相似文献   
65.
The iliac crest bone grafting (ICBG) technique for lumbar posterolateral fusion surgery is widely used; however, donor site problems such as pain and sensory disturbance have been reported. Local bone is available for fusion surgery, but its reliability as a graft has not been fully reported. In the current study, we examined single-level instrumented posterolateral fusion with a local bone graft versus an ICBG in a prospective randomized study. Eighty-two patients diagnosed with L4 degenerated spondylolisthesis were divided into two groups at random. Forty-two patients underwent instrumented posterolateral fusion with a local bone graft (L4–L5 level), and 40 patients underwent instrumented posterolateral fusion with an ICBG (L4–L5 level). Rate and duration of bone union, visual analog scale (VAS) score, Japanese orthopedic association score (JOAS), Oswestry Disability Index (ODI), and complications were evaluated before and 2 years after therapy. VAS score, JOAS, and ODI were not significantly different between the two groups before and after surgery (P > 0.05). Rate and average duration of bone union were 90% and 8.5 months in the local bone graft group, and 85% and 7.7 months in the ICBG group, but without significant difference (P > 0.05). Prolonged surgical time and complications such as donor site pain (8 patients) and sensory disturbance (6 patients) were observed in the ICBG group. If single-level posterolateral fusion was performed, local bone graft technique has the same bone union rate compared with ICBG, requires less surgical time, and has fewer complications.  相似文献   
66.
Doi Y  Miyazaki M  Yoshiiwa T  Hara K  Kataoka M  Tsumura H 《BONE》2011,49(4):777-782
Bone repair involves a complex set of regulated signaling pathways that control the formation of new bone matrix and the resorption of damaged bone matrix at the fracture site. It has been reported that the optimal time point for single-dose zoledronic acid (ZA) administration systemically increased the strength of bone morphogenetic protein (BMP)-7-mediated callus. However, its repair mechanism during bone fracture healing remains unknown. We aimed to investigate the synergic effect of recombinant human (rh) BMP-2 and ZA in a rat femoral fracture model. Fifty-eight rats were divided into 4 groups. Group I (n = 14) animals were implanted with a carrier alone. Group II (n = 15) animals were implanted with a carrier containing 1-μg rhBMP-2. Group III (n = 14) animals were implanted with a carrier and a subcutaneous systemic ZA injection 2 weeks after surgery. Group IV (n = 15) animals were implanted with a carrier containing 1-μg rhBMP-2 and ZA subcutaneous injection 2 weeks after surgery. The rats were euthanized after 6 weeks and their fractured femurs were explanted and assessed by manual palpation, radiographs, and high-resolution micro-computerized tomography (micro-CT) and were subjected to biomechanical and histological analysis. The fusion rates in Group IV (93.3%) were considerably higher than those in Groups I (28.6%), II (53.3%), and III (57.1%). Additionally, the radiographic scores of Group IV were higher than those in Groups I, II, and III. In micro-CT analysis, the tissue volume (TV) of the callus was higher in Group IV than in Groups I and II (p < 0.05). New bone volume (BV) and trabecular spacing (Tb.Sp) also showed essentially the same trend as that of TV. The ratio of BV to TV (BV/TV), the trabecular number (Tb.N), and the trabecular thickness (Tb.Th) was higher in Groups III and IV than in Groups I and II (p < 0.05). In biomechanical analysis, the ultimate loads at failure and stiffness in Groups III and IV were on average higher than those in Groups I and II (p < 0.05), while the energy absorption of Group IV was higher than those of Groups I and II (p < 0.05). The synergic effect of rhBMP-2 and ZA given systemically as a single dose at the optimal time was efficacious for fracture repair and significantly enhanced bone fusion. Our results suggest that this combination facilitates bone healing and has potential clinical application.  相似文献   
67.
BACKGROUND: Microwave coagulation therapy (MCT) has become a safe and effective modality with which to treat hepatic tumors; MCT can be applied percutaneously, laparoscopically, thoracoscopically, and during laparotomy. When combined with magnetic resonance (MR) imaging, MCT can be used to treat hepatic tumors located in the subdiaphragmatic area that are difficult to approach by ultrasound, because of the overlaying lower lung field. METHODS: To determine the usefulness of thoracoscopy-assisted interventional MR-MCT (T-IVMR-MCT, n = 73), we compared patients with hepatic tumors that were treated with percutaneous IVMR-MCT (P-IVMR-MCT, n = 69) and with T-IVMR-MCT. RESULTS: None of patient background, complication and recurrence rate, or length of hospital stay significantly differed between the 2 groups. CONCLUSIONS: IVMR-MCT is a useful modality for treating hepatic tumors. Especially when tumors are located at the hepatic dome, T-IVMR-MCT was minimally invasive, while it appears to improve targeting of peridiagmatic hepatic lesions and has a complication profile similar to P-IVMR-MCT.  相似文献   
68.
Purpose Aurora-A, also known as STK15/BTAK, is a member of the protein serine/threonine kinase family, and experimental studies have revealed that Aurora-A plays critical roles in cell mitosis and in carcinogenesis. However, no clinical studies on Aurora-A expression in non-small-cell lung cancer (NSCLC) have been reported. Thus, the present study was conducted to assess the clinical significance of Aurora-A status. Experimental Design A total of 189 consecutive patients with resected pathologic (p-)stage I-IIIA, NSCLC were retrospectively reviewed, and immunohistochemical staining was used to detect Aurora-A expression. Results Aurora-A expression was negative in 31 patients (16.4%); among Aurora-A positive patients, 124 patients showed pure diffuse cytoplasmic Aurora-A expression and the other 34 patients showed perimembrane Aurora-A expression. Perimembrane Aurora-A tumors showed the highest proliferative index (PI) (mean PIs for negative, diffuse cytoplasmic, and perimembrane tumors: 49.2, 41.7, and 63.5, respectively; P < .001). Five-year survival rates of Aurora-A negative, diffuse cytoplasmic, and perimembrane patients were 67.8%, 66.7%, and 47.6%, respectively, showing the poorest postoperative survival in perimembrane patients (P = .033). Subset analyses revealed that perimembrane Aurora-A expression was a significant factor to predict a poor prognosis in squamous cell carcinoma patients, not in adenocarcinoma patients. A multivariate analysis confirmed that perimembrane Aurora-A expression was an independent and significant factor to predict a poor prognosis. Conclusions Perimembrane Aurora-A status was a significant factor to predict a poor prognosis in correlation with enhanced proliferative activity in NSCLC.  相似文献   
69.
AIMS: This review aims to discuss: 1) the neurophysiology, highlighting the importance of the middle urethra, and treatment of stress urinary incontinence (SUI); 2) current injectable cell sources for minimally-invasive treatment; and 3) the potential of muscle-derived stem cells (MDSCs) for the delivery of neurotrophic factors. METHODS: A PUB-MED search was conducted using combinations of heading terms: urinary incontinence, urethral sphincter, stem cells, muscle, adipose, neurotrophins. In addition, we will update the recent work from our laboratory. RESULTS: In anatomical and functional studies of human and animal urethra, the middle urethra containing rhabdosphincter, is critical for maintaining continence. Cell-based therapies are most often associated with the use of autologous multipotent stem cells, such as the bone marrow stromal cells. However, harvesting bone marrow stromal stem cells is difficult, painful, and may yield low numbers of stem cells upon processing. In contrast, alternative autologous adult stem cells such as MDSCs and adipose-derived stem cells can be easily obtained in large quantities and with minimal discomfort. Not all cellular therapies are the same, as demonstrated by the differences in safety and efficacy from muscle-sourced MDSCs versus myoblasts versus fibroblasts. CONCLUSIONS: Transplanted stem cells may have the ability to undergo self-renewal and multipotent differentiation, leading to sphincter regeneration. In addition, such cells may release, or be engineered to release, neurotrophins with subsequent paracrine recruitment of endogenous host cells to concomitantly promote a regenerative response of nerve-integrated muscle. The dawn of a new paradigm in the treatment of SUI may be near.  相似文献   
70.
OBJECTIVE: Left atrial (LA) volume reduction surgery concomitant with the maze procedure has been reported to facilitate sinus rhythm recovery even in patients with refractory atrial fibrillation (AF) with an enlarged LA. However, it is unknown whether the procedures can also restore effective atrial function of the enlarged LA with over-stretched myocardium. METHODS: The maze procedures in association with mitral valve surgery were performed to 57 AF patients with an enlarged LA (LA diameter >or=60mm). Among them, 32 patients had concomitant LA volume reduction surgery (VR group). Another 25 patients did not have the volume reduction (control group). RESULTS: Three months postoperatively LA end-diastolic volume (LAEDV, ml) assessed by magnetic resonance (MR) imaging was larger in the VR group than that in the control group (291+/-117 vs 223+/-81 ml, p<0.05). Postoperatively, sinus rhythm recovery rate was better (84 vs 68%, p<0.05) and LAEDV was drastically smaller (118+/-48 vs 203+/-76 ml, p<0.001) in the VR group than those in the control group. Among the patients with sinus rhythm recovery in both groups, LA contraction ejection fraction (%) improved in the VR group but not in the control group (22.3+/-7.8 vs 10.3+/-4.7%, p<0.001). CONCLUSIONS: The LA volume reduction surgery concomitant with the maze procedure restored contraction of the enlarged LA; however, the maze procedure alone did not restore LA contraction in spite of successful sinus rhythm recovery. LA volume reduction surgery may be desirable to the patients with refractory AF with over-stretched LA.  相似文献   
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