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901.
We analyzed the histological high-risk factors for recurrence of submucosal invasive carcinomas (pT1) of the colon and rectum after endoscopic therapy, examining pT1 cancers treated primarily by endoscopic resection within a 23-year period. We compared recurrent and nonrecurrent cancers, evaluating the following "highrisk factors" of the primary lesion: massive invasion, a surgical margin <2 mm but negativity for cancer in the cut end, poorly differentiated adenocarcinoma (PD) (G3), undifferentiated carcinoma (G4), and/or positive angiolymphatic invasion. The following histological factors were defined as predictive of a low risk: minimum invasion, a surgical margin >2 mm, well or moderately differentiated adenocarcinoma (G1, G2), and no evidence of angiolymphatic invasion. We analyzed the records of 37 patients with pT1 cancers, including 15 with high-risk factors who underwent subsequent resection. Local recurrence with or without liver metastases developed in 4 of these 15 patients. The histological type was PD in three (75%) of the four recurrent lesions. All four (100%) lesions showed a desmoplastic response (DR). Only 1 (9%) of the 11 patients without recurrence after subsequent surgery had a lesion with a small component of PD, and only three (27%) lesions showed a mild DR. We concluded that endoscopic therapy is inadequate for pT1 cancers with a histological PD component, and/or a DR in the cancer stroma.  相似文献   
902.
It has been reported that alfacalcidol had an anticatabolic and anabolic effect on bone in ovariectomized and aged male rat models, but this has not been tested on intact female rats. The current study was to determine the effects of alfacalcidol on cancellous and cortical bone in intact female rats with or without exercise. Seventy-four, 8.5-month-old, intact female rats were orally treated with 0, 0.005, 0.025, 0.05, or 0.1 microg/kg alfacalcidol alone or in combination with raised cage (RC) exercise for 3 months. In vivo peripheral quantitative computerized tomography (pQCT) of the proximal tibial metaphyses (PTM) and ex vivo histomorphometric analyses of the PTM and tibial shaft (TX) were performed. Only the 0.1 microg alfacalcidol/kg dose proved to be anabolic. pQCT analysis showed that this dose increased total and cortical bone mineral content and density and trabecular bone mineral density. Histomorphometrically, it induced an anabolic response by increased trabecular mass and microarchitecture from stimulated cancellous bone and bone bouton formations, and suppressed bone resorption more than bone formation on the trabecular and endocortical surfaces, to produce a positive bone balance. A positive correlation between trabecular connectivity and bone bouton numbers occurred. These findings suggest alfacalcidol treatment augments bone mass by increased cancellous bone mass and improved trabecular architecture through its anticatabolic and anabolic properties in the intact adult female rat. Last, raised cage exercise alone or the combination of raised cage and alfacalcidol was no more effective than alfacalcidol alone.  相似文献   
903.
904.
The incidence of intraoperative femoral fractures with a single design of stem implant, the Meridian (Stryker-Howmedica, Rutherford, N.J.), has been assessed in a study of 117 implants in patients treated consecutively between 1996 and 2001. The aim of the study was to evaluate the risk factors for suffering an intraoperative fracture and to determine, based on a short-term follow-up, if there were radiographic signs of early loosening. The following variables were analysed: demographic factors of the patient, morphology of the femur, intraoperative factors and postoperative radiographic factors. The radiographic stability of the implant and the presence of early signs of loosening were evaluated 2 years after surgery. The incidence of femoral fractures was 11% (13 cases in 117 implants), which is higher that reported in earlier published studies, and there was an increased number of fractures when the proximal filling of the femoral canal was higher. Although there was no statistically significant relation between the variables studied and the appearance of an intraoperative fracture, we conclude that the appearance of a femoral intraoperative fracture did not affect the radiographic stability of the implant during the short-term follow-up of our study cohort.  相似文献   
905.
Background This study was carried out to evaluate the effectiveness of anterior plating with subsequent percutaneous iliosacral screwing for the management of unstable pelvic ring injuries. Methods Nineteen patients with unstable pelvic ring injuries were included in this retrospective study. All patients were followed up for at least 1 year, and their mean age was 43 years. According to the Association for Osteosynthesis-Orthopaedic Trauma Association (AO-OTA) classification, there were 5 B2 injuries, 11 C1 injuries, and 3 C2 injuries. After anterior fixation by means of plating, an iliosacral screw fixation was carried out percutaneously using a C-arm fluoroscope. Results All fractures healed, except for 1 case of nonunion at the pubic ramus. Radiological results showed that there were 9 anatomic, 7 nearly anatomic, 2 moderate, and 1 poor reduction. Sixteen of the 19 patients had good or excellent results for function, and all these had satisfactory (anatomic or nearly anatomic) reductions. The two moderate and 1 poor result were from an unsatisfactory reduction in a type-C injury with residual neurological signs. A screw misplacement with a neurological compromise occurred in 1 patient, but there were no adverse sequelae after its removal. The complications encountered were 2 cases of screw loosening, 2 cases of anterior metal failure, and 1 deep infection. Conclusions Anterior plating with subsequent percutaneous iliosacral screwing may be a useful method of treatment for unstable pelvic ring injuries, and the reduction quality and residual neurological signs were important in its functional outcome.  相似文献   
906.
We assessed the potential clinical utility of levels of p53-specific antibodies as a novel serum biomarker of prostate cancer that could be used in conjunction with level of PSA. Material and methods Serum levels of p53-specific antibodies in patients with relapsed, newly diagnosed prostate cancer and in patients with benign prostate hyperplasia were quantified by an enzyme-linked immunoabsorbent assay. Result There was no significant difference (P = 0.96) between the serum levels of p53-specific antibodies in patients with newly diagnosed prostate cancer and with benign prostatic hyperplasia. In the newly diagnosed prostate cancer group, stage T1c (n = 8) showed the lowest p53-specific antibody level. However, the difference between T1c group and benign prostatic hyperplasia group was not significant (P = 0.686). The relapsed cancer group tended to have low levels of the antibodies, and, there was no significant difference between the relapsed prostate cancer group and the benign prostatic hyperplasia group (P = 0.14). The serum levels of p53-specific antibodies in patients with metastatic and with localized prostate cancer showed no significant difference (P = 0.68). Conclusion The use of titers of p53-specific antibodies to make differential diagnosis between prostate cancer and benign prostatic hyperplasia might have no role, and the antibodies should not be used as a marker of prostate cancer by itself. Because our study is based on small number of patients, further studies are necessary before its absolute validity can be determined.  相似文献   
907.
Background Voice and swallowing symptoms are frequently reported after thyroidectomy even in absence of objective voice alterations. We evaluated the influence of the video-assisted approach on voice and swallowing outcome of thyroidectomy. Methods Sixty-five patients undergoing total thyroidectomy (TT) were recruited. Eligibility criteria were: nodule size ≤30 mm, thyroid volume ≤30 ml, no previous neck surgery. Exclusion criteria were: younger than aged 18 years and older than aged 75 years, vocal fold paralysis, history of voice, laryngeal or pulmonary diseases, malignancy other than papillary thyroid carcinoma. Patients were randomized for video-assisted (VAT) or conventional (CT) thyroidectomy. Videostrobolaryngoscopy (VSL), acoustic voice analysis (AVA), and maximum phonation time (MPT) evaluation were performed preoperatively and 3 months after TT. Subjective evaluation of voice (voice impairment score = VIS) and swallowing (swallowing impairment score = SIS) were obtained preoperatively, 1 week, 1 month, and 3 months after TT. Results Fifty-three patients completed the postoperative evaluation: 29 in the VAT group, and 24 in the CT group. No laryngeal nerves injury was shown at postoperative VSL. Mean postoperative MPT, F 0, F low, F high, and the number of semitones were significantly reduced in the CT group but not in the VAT group. Mean VIS 3 months after surgery was significantly higher than preoperatively in CT group but not in the VAT group. Mean SIS was significantly decreased 1 and 3 months after VAT but not after CT. Conclusions The incidence and the severity of early voice and swallowing postthyroidectomy symptoms are significantly reduced in patients who undergo VAT compared with conventional surgery. Presented at the ISW2007—IAES free paper session, Montreal, Canada, August 26–30, 2007.  相似文献   
908.
We compare the effects of estrogen and/or ghrelin on vascular counts and collagen I/III ratio of urethral and anal canal submucosa in old vs young-adult ovariectomized rats. Ovariectomized Fisher 344 rats (18 and 3 months old, n = 24 x 2) received 42 daily intraperitoneal 17-ss estradiol (10 microg/kg), ghrelin (2 microg/kg), both, or vehicle (n = 6 x 4 per group). Blood vessel counts and collagen I/III ratio were measured, respectively, by light microscopy and Western blot analysis with immunohistochemistry of ghrelin receptors. Estrogen significantly increased urethral and anal vascular counts and collagen I/III ratio in young-adult rats. In old rats, only combined estrogen/ghrelin administration significantly increased both variables. This was not observed with estrogen or ghrelin separately. Ghrelin receptors were immunostained in urethral and anal submucosa of all samples. Combined estrogen/ghrelin administration restored postovariectomy urethral and anal canal submucosal vessel number and collagen I/III ratio in old rats suggesting independent ageing effect.  相似文献   
909.
The author describes a technique for vermilion reconstruction after excision of an involuted hemangioma scar in the upper lip in an adult female patient. Reconstruction was achieved by making use of all the available vermilion tissue remaining after a triangular excision of the scar. The incision is in the form of a horizontal “K” with extended limbs and repair by advancing and interdigitating the two medial and lateral triangular vermilion flaps with a final Z-shaped suture line. The advancement is like a modified double opposing Y–V plasty. This was complemented by a simple Z-plasty of the labial mucosa to correct an existing notch and deficiency of the free mucosal border. The aesthetic result was excellent; thus, its use can be considered when closing any similar defects resulting from scars or small benign lesion excisions.  相似文献   
910.

Background

Hyperthermic intraperitoneal chemotherapy (HIPEC) is being evaluated for patients with minimal residual or no residual disease after primary surgery and chemotherapy for stage III ovarian carcinoma. The technical feasibility of the laparoscopic approach for HIPEC has been demonstrated in a previous study. An experimental study on the porcine model was carried out to compare oxaliplatin pharmacokinetics during a laparoscopic-assisted procedure versus the coliseum technique for HIPEC.

Methods

Adult pigs received an HIPEC procedure that was based on 460 mg/m2 of oxaliplatin over 30 minutes with a perfusate heated at 41°C to 43°C. The HIPEC drains were placed in the upper and lower quadrants of the abdomen. Peritoneal fluid and blood samples were collected every 10 minutes during the procedure, and the pharmacokinetics of oxaliplatin was studied.

Results

Two groups of 10 adult pigs were studied. All the procedures were successfully completed with an adequate intra-abdominal temperature and distribution. No major technical problems were encountered. At the end of the HIPEC, 41.5% of the molecule was absorbed in the laparoscopic group compared with 33.4% in the laparotomy group (P = .0543). Peritoneal oxaliplatin half-life (T½) was significantly faster in the laparoscopic procedure (median, 37.5 vs. 59.3 minutes, P = .02). The area under the curve ratio of peritoneal to plasma reflects a more important oxaliplatin crossing through the peritoneal barrier in the laparoscopic procedure (ratio, 16.4 in the closed procedure vs. 28.1 in the open one; P = .03).

Conclusions

This study confirms the technical feasibility and reliability of the laparoscopic approach for HIPEC, and it extends knowledge concerning peritoneal drug absorption. Oxaliplatin absorption is far higher with laparoscopy in terms of time course in peritoneal perfusion. Clinical application in selected patients may be expected after further experimental investigation designed to define the adequate drug dosage.
  相似文献   
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