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81.
Mesenchymal stem cells (MSC) are present in specialized niches in perivascular regions of adult tissues and are able to differentiate into various cell types, such as those committed to repairing. Bone marrow derived MSC from eight young mice C57BL/ 6 gfp+ were expanded in culture for repairing critical defects in calvarial bone produced in twenty-four young isogenic adult C57BL/6 mice. The animals were subjected to a cranial defect of 6.0mm diameter and divided into two equal experimental groups. Control group did not receive any treatment and the treated group received a MSC pellet containing 1.0 x 10(7) cells/mL into the defects. The group treated with MSC showed increased angiogenesis and amount of new bone deposited on the defect limits than that observed in the control group. The results demonstrated that transplantation of bone marrow-derived MSC of C57BL/6 gfp+ mice to bone critical defects produced in mice calvarial contributes positively to the bone repair process. MSC presets ability to influence the correct functioning of osteoblasts, increases the amount of mobilized cells for the repairing process, speeds up growth, and increases deposition of bone matrix.  相似文献   
82.

Introduction and hypothesis

Intravesical instillations of hyaluronic acid (HA) and chondroitin sulfate (CS) may lead to regeneration of the damaged glycosaminoglycan layer in interstitial cystitis/bladder pain syndrome (IC/BPS).

Methods

Twenty-two patients with IC/BPS received intravesical instillations (40?ml) of sodium HA 1.6% and CS 2.0% in 0.9% saline solution (IALURIL?, IBSA) once weekly for 8?weeks, then once every 2?weeks for the next 6?months.

Results

The score for urgency was reduced from 6.5 to 3.6 (p?=?0.0001), with a reduction in pain scores from an average of 5.6 to 3.2 (p?=?0.0001). The average urine volume increased from 129.7 to 162?ml (p?p?p?p?Conclusion The treatment appeared to be effective and well tolerated in IC/BPS in this initial experience.  相似文献   
83.
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85.
OBJECTIVE: The objective of our study was to analyze the sonography examinations of nine consecutive patients with a history of distal radius fracture treated by open reduction and internal fixation of the volar plate who were referred by hand surgeons for sonography of the dorsal aspect of the wrist. CONCLUSION: We postulate that impingement of the extensor tendons in patients with distal radius fracture treated by volar plating starts with local hyperemia and is followed by tenosynovitis and, finally, by partial and complete tendon tears. Sonography is an effective, dynamic, and noninvasive technique with which to diagnose and evaluate damage to the extensor tendons and their synovial sheaths.  相似文献   
86.
Bello L  Lucini V  Giussani C  Carrabba G  Pluderi M  Scaglione F  Tomei G  Villani R  Black PM  Bikfalvi A  Carroll RS 《Neurosurgery》2003,52(1):177-85; discussion 185-6
OBJECTIVE: The biological features of malignant gliomas include high cell proliferation, extensive local infiltration of tumor cells into normal brain, and marked neovascularization. alphavbeta3 integrin is highly expressed in malignant gliomas and plays a role in glioma growth. This article investigates the in vitro and in vivo effects of a synthetic alphavbeta3 integrin inhibitor called IS20I on human malignant gliomas. METHODS: The in vitro effects of IS20I were studied by performing adhesion assays, competition studies, semi-in vivo angiogenic assays, and migration and proliferation assays. For the in vivo experiments, IS20I was administered systemically in nude mouse intracranial and subcutaneous malignant glioma models. RESULTS: IS20I reacted selectively to alphavbeta3 integrin in glioma cells and tissues. In vitro, IS20I strongly inhibited angiogenesis and simultaneously exhibited potent antimitotic and antimigratory effects on numerous tumor and endothelial cell lines. In addition, at high concentrations, IS20I induced endothelial and tumor cell apoptosis. In vivo, when IS20I was administered intraperitoneally in subcutaneous and intracranial nude mouse glioma models, it potently reduced malignant glioma growth. Inhibition levels of 76 and 82% were observed at concentrations of 1 and 5 mg/kg, respectively, in the U87 intracranial model. The suppression of tumor growth is associated with a decrease in tumor vascularity, an increase in apoptosis, and a decrease in tumor cell proliferation. CONCLUSION: This work expands the understanding of the effects of anti-alphavbeta3 integrin inhibitors on malignant gliomas. In addition to direct proapoptotic and antiangiogenic effects, IS20I inhibits tumor and endothelial cell proliferation and migration, resulting in a potent inhibition of glioma growth in vivo.  相似文献   
87.

Background

Until now technologic evolution in coronary bypass surgery has focused on extracorporeal circulation, on operation without extracorporeal circulation, and on the exposure of the operative site. Recently a one-shot anastomotic device for the proximal anastomosis in coronary surgery was developed. We investigated whether the use of the aortic connector system (ACS) could facilitate the creation of aortosaphenous vein graft anastomoses in myocardial revascularization.

Methods

From November 2000, 40 ACS devices were used in 36 consecutive patients (mean age 70.7 ± 8.9 years); 12 patients (33.3%) underwent surgery on pump and 24 patients (66.6%) off pump; 50 distal anastomoses were performed. In all cases the connection with the ascending aorta was created before the distal anastomoses because of the necessity to slide the saphenous vein graft (SVG) over the vein transfer sheath. Intraoperative graft function was tested measuring blood flow by Doppler analysis. Postoperative evaluation of the anastomotic patency was carried out by early angiography in 34 patients (94.7%) but was excluded in 5 patients (5.3%) with extensive extracardiac vascular occlusive disease.

Results

Of 38 AC (95%) evaluated, 36 (94.7%) functioned properly. The end-to-side proximal anastomosis without aortic clamping is instantaneous, the quality of anastomoses was highly rated, no additional stitches were required, and all coronary arteries could be reached. Intraoperative quantity flow was measured by Doppler analysis and all but one showed good flow. Early postoperative angiography demonstrated good patency of the grafts in all cases but 2 (5.3%). At 1-year follow-up, 1 patient died of stroke; all other patients remained free of symptoms and no reoperation was required.

Conclusions

The use of ACS makes end-to-side anastomosis rapid, effective, and reproducible while eliminating aortic cross clamping; it opens a new era in beating or nonbeating coronary surgery. Long-term results are mandatory to confirm our favorable preliminary results.  相似文献   
88.

Purpose

The aim of this study was to define the predictive value of colonic manometry and contrast enema before cecostomy placement in children with defecation disorders.

Methods

Medical records, contrast enema, and colonic manometry studies were reviewed for 32 children with defecation disorders who underwent cecostomy placement between 1999 and 2004. Diagnoses included idiopathic constipation (n = 13), Hirschsprung's disease (n = 2), cerebral palsy (n = 1), imperforate anus (n = 6), spinal abnormality (n = 6), and anal with spinal abnormality (n = 4). Contrast enemas were evaluated for the presence of anatomic abnormalities and the degree of colonic dilatation. Colonic manometry was considered normal when high-amplitude propagating contractions (HAPC) occurred from proximal to distal colon. Clinical success was defined as normal defecation frequency with no or occasional fecal incontinence.

Results

Colonic manometry was done on 32 and contrast enema on 24 patients before cecostomy. At follow-up, 25 patients (78%) fulfilled the success criteria. Absence of HAPC throughout the colon was related to unsuccessful outcome (P = .03). Colonic response with normal HAPC after bisacodyl administration was predictive of success (P = .03). Presence of colonic dilatation was not associated with colonic dysmotility.

Conclusion

Colonic manometry is helpful in predicting the outcome after cecostomy. Patients with generalized colonic dysmotility are less likely to benefit from use of antegrade enemas via cecostomy. Normal colonic response to bisacodyl predicts favorable outcome.  相似文献   
89.
Background  Roentgenographic and functional outcomes of expandable self locking intramedullary nailing and platelet rich plasma (PRP) gel in the treatment of long bone non-unions are reported. Materials and methods  Twenty-two patients suffering from atrophic diaphyseal long bone non-unions were enrolled in the study. Patients were treated with removal of pre-existing hardware, decortication of non-union fragments, and fixation of pseudoarthrosis with expandable intramedullary nailing (Fixion™, Disc’O Tech, Tel Aviv, Israel). At surgery, PRP was placed in the pseudoarthrosis rim. Results  The thirteen-month follow-up showed 91% (20/22 patients) of patients attaining bony union. The average time to union was 21.5 weeks. No infection, neurovascular complication, rotational malalignment, or limb shortening >4 mm were observed. The healing rate of non-unions was comparable to that observed in previous studies but with a lower complication frequency. Conclusions  The combined use of self locking intramedullary nailing and PRP in the management of atrophic diaphyseal long bone non-unions seems to produce comparable results with less complications than previously reported. Further data are warranted to investigate the single contribution of PRP gel and Fixion nail.  相似文献   
90.
Ejaculatory dysfunction (EjD) is one of the most common male sexual disorders, yet EjD is still frequently misdiagnosed or overlooked as a result of numerous patient and physician barriers. The wide spectrum of EjD ranges from premature or rapid ejaculation, through delayed ejaculation, to a complete inability to ejaculate--otherwise known as anejaculation--and includes retrograde ejaculation and painful ejaculation. Conventional algorithms for managing ejaculatory disorders are based either on an organic or psychogenic etiology, with the latter more traditionally considered the main cause. This paper reviews physiopathological, diagnostic and therapeutic aspects of ejaculation disorders, with a particular focus on the most prevalent disorder, premature ejaculation.  相似文献   
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