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91.
The aim of the study was to compare the long-term stability of membranous and endochondral autogenous bone grafts with or without combined application of guided bone regeneration (GBR). Twenty-five, male, 6-month old, albino rats were used in the study. The animals were divided into four groups (A5, A11, B5 and B11). Group A5 (control): The inferior border of the mandible was exposed in both sides. At one side of the jaw, a calvarial bone graft (baseline -3 x 4 x 0.64 mm) was placed at the inferior border of the mandible and was fixed with a standardized screw-type titanium microimplant. At the contralateral side, an ischiac bone graft (baseline -3 x 4 x 0.87) was transplanted. The healing period was 5 months. Group A11 (control): The animals were treated in the same manner as in Group A5 with the difference that the healing period was 11 months. Group B5 (test): The animals were treated in the same manner as in Group A5 with the difference that an e-PTFE membrane was adapted over the bone graft on each side of the jaw. Group B11 (test): The animals were treated in the same manner as in Group B5 with the difference that 5 months following transplantation the animals were subjected to a second operation and the membranes were removed. The healing period was 11 months. The animals were killed at 5 (Groups A5 and B5) or at 11 months (Groups A11 and B11) following mandibular augmentation and the jaws were defleshed. The width, the length and the thickness/height of the bone graft were evaluated by means of a stereomicroscope. At 5 months, both types of the membrane-treated bone grafts presented increase in all dimensions compared with baseline. However at 11 months, both types of the membrane-treated bone grafts exhibited a decrease in their dimensions which were similar to the baseline measurements. In the control groups, both types of bone graft presented significant resorption both at 5 and at 11 months with the ischiac bone grafts presenting more resorption in width and length than the calvarial bone grafts. It can be concluded that the long-term volume stability of autogenous endochondral and membranous onlay bone grafts combined with GBR is superior to that of autogenous endochondral and membranous onlay bone grafts alone.  相似文献   
92.
PURPOSE: The aim of this study was to compare bone healing and crestal bone changes following immediate (Im) versus delayed (De) placement of titanium dental implants with acid-etched surfaces (Osseotite) in extraction sockets. MATERIALS AND METHODS: Forty-six patients were randomly allocated to the Im or De group (n = 23 per group) and received 1 implant at the incisor, canine, or premolar region of the maxilla or the mandible. The implants were placed an average of 10 days following tooth extraction in the Im group and approximately 3 months after extraction in the De group. The widths (parallel and perpendicular to the implant) and the depth of marginal bone defects around the implants were measured clinically just after placement and 3 months later at the abutment surgery. The crestal bone changes mesially and distally to the implants were evaluated radiographically by linear measurements. RESULTS: The survival rates were 91% in the Im group and 96% in the De group. In the Im group, the mean reductions in parallel width, perpendicular width, and depth of the largest defect of each implant amounted to 48% (from 4.4 to 2.3 mm), 59% (from 2.2 to 0.9 mm), and 48% (from 6.9 to 3.6 mm), respectively. The corresponding mean reductions in the De group amounted to 39% (from 3.1 to 1.9 mm), 77% (from 1.3 to 0.3 mm), and 34% (from 4.4 to 2.9 mm). The reduction over time was statistically significant in both groups (P < .04). For both groups, a higher degree of bone healing was achieved in the infrabony defects (> 60% for depth) than in dehiscence-type defects (approximately 25%). Furthermore, 70% of the 3-wall infrabony defects with a parallel width of up to 5 mm, a depth of maximum 4 mm, and a perpendicular width of maximum 2 mm had a capacity of spontaneous healing within a period of 3 months. DISCUSSION AND CONCLUSION: New bone formation occurs in infrabony defects associated with immediately placed implants in extraction sockets.  相似文献   
93.
Purpose The expression of erbB2 and erbB3 receptors was investigated in an experimental model of chemically induced oral carcinogenesis in normal and diabetic (type I) Sprague-Dawley rats. Methods Thirteen diabetic and twelve normal rats developed precancerous and cancerous lesions after 4-nitroquinoline-N-oxide treatment, while six diabetic and six normal animals were used as controls. Sections of biopsies from all animals were classified histologically in the following categories: normal mucosa, hyperplasia, dysplasia, early invasion, well- and moderately-differentiated squamous cell carcinoma. Each section was studied immunohistochemically using monoclonal antibodies against erbB2 and erbB3 proteins and six representative histological regions in each section were analysed. Results The erbB2 was expressed at very low levels in normal rats, while in diabetic animals its expression was significantly increased during early invasion (P = 0.04). The erbB3 expression was significantly elevated in well-differentiated carcinoma in normal animals (P = 0.01), while in diabetic animals it was significantly increased during oral mucosal hyperplasia and dysplasia (P = 0.03 and 0.0007, respectively). The comparison of erbB2 expression between diabetic and normal rats revealed significant differences in all stages except for the tumor stage of moderately differentiated carcinoma (P = 0.01, 0.00001, 0.00001, 0.003, and 0.00001). In regard to erbB3 expression, significant differences between diabetic and normal rats existed only in normal, non-cancerous and precancerous stages (P = 0.007, 0.0001, 0.0003). Conclusions It seems that diabetes enhances the expression of both erbB2 and erbB3 in certain stages of oral oncogenesis possibly resulting in promotion of cell proliferation and inhibition of apoptosis.  相似文献   
94.

Purpose

Screw fixation (osteosynthesis) can be performed percutaneously by interventional radiologists. We report our experience in cancer patients.

Material/methods

We retrospectively reviewed all cases of percutaneous osteosynthesis (PO) of the pelvic ring and proximal femur performed in our hospital. PO were performed for fracture palliation or for osteolytic metastases consolidation. Screws were inserted under CT- or cone-beam CT- guidance and general anaesthesia. Patients were followed-up with pelvic-CT and medical consultation at 1 month, then every 3 months. For fractures, the goal was pain palliation and for osteolytic metastases, pathologic fracture prevention.

Results

Between February 2010 and August 2014, 64 cancer patients were treated with PO. Twenty-one patients had PO alone for 33 painful fractures (13 bone-insufficiency, 20 pathologic fractures). The pain was significantly improved at 1 month (VAS score?=?20/100 vs. 80/100). In addition, 43 cancer patients were preventively consolidated using PO plus cementoplasty for 45 impending pathologic fractures (10 iliac crests, 35 proximal femurs). For the iliac crests, no fracture occurred (median-FU?=?75 days). For the proximal femurs, 2 pathological fractures occurred (fracture rate?=?5.7 %, median-FU?=?205 days).

Conclusion

PO is a new tool in the therapeutic arsenal of interventional radiologists for bone pain management.

Key Points

? Screw fixation (osteosynthesis) can be performed percutaneously by interventional radiologists. ? CT- or CBCT-guidance results in high technical success rates for screw placement. ? This minimally invasive technique avoids extensive surgical exposure in bone cancer patients. ? Osteosynthesis provides pain relief for bone-insufficiency fractures and for pathologic fractures. ? Osteosynthesis plus cementoplasty provide prophylactic consolidation of impending pathological fractures.
  相似文献   
95.
PURPOSE: The purpose of this study was to access the reliability and use of the superiorly based platysma flap for reconstruction of small and medium oral defects. PATIENTS AND METHODS: This case series consists of 5 patients who were reconstructed with a superiorly based platysma flap for defects of the following oral region: buccal mucosa, floor of the mouth, and lateral gingiva. The flaps were monitored for complications, including skin loss and ischemia in the postoperative period. RESULTS: Three patients (60%) had some skin sloughing in the recipient site. None of the patients had complications in the donor site. CONCLUSION: The superiorly based platysma flap can survive after the facial artery has been ligated, which is the normal procedure during neck dissection. If skin sloughing occurs, it is usually inconsequential for intraoral reconstruction because the underlying muscle remains viable and undergoes epithelialization.  相似文献   
96.
BACKGROUND: An increasing incidence of delayed hemolytic and delayed serologic transfusion reactions (DHTRs/DSTRs) has been seen at the Mayo Clinic since 1978. Recently, the average length of stay (LOS) for inpatients and the average number of red cell transfusions per inpatient (TPI) decreased, and the albumin and papain technique for RBC antibody detection was replaced by a polyethylene glycol technique. These changes may have affected the incidence of DHTRs/DSTRs. STUDY DESIGN AND METHODS: The diagnoses of DHTR and DSTR made at the Mayo Clinic from 1993 through 1998 were reviewed. These data were compared with previously published Mayo Clinic data from 1980 through 1992. The LOS for inpatients and the average TPI were also obtained from hospital data. RESULTS: The incidence of DHTR/DSTR increased from 1 in 1899 in 1980 through 1992 to 1 in 1300 in the 1993 through 1998 period (p < 0.05). Similarly, DSTR increased from 1 in 2990 in 1980 through 1992 to 1 in 1612 in the 1993 through 1998 period (p < 0.05). The incidence of DHTR showed a trend toward decrease, from 1 in 5405 in 1980 through 1992 to 1 in 6715 in 1993 through 1998. No alloantibody specificities were statistically associated with DHTRs in 1993 through 1998, unlike in the 1980 through 1992 period. Moreover, the incidence of Jka antibodies increased in 1993 through 1998, while the incidence of other alloantibodies remained stable. Average LOS and TPI declined by 24.5 percent and 8.8 percent, respectively, between the two periods. CONCLUSION: Recently, a trend toward a decrease in the incidence of DHTR and a significant increase in DSTRs has occurred at the Mayo Clinic. These changes are most likely due to a combination of factors, including a decrease in average LOS and the adoption of the polyethylene glycol antibody detection system.  相似文献   
97.
The present study reports on a 17-year-old male who ingestedapproximately 70 ml trichloroethene (TRI) in a suicide attempt.The patient developed fever, tremor, general motor restlessness, and sinus tachycardia and lost consciousness 5 h after poisoning.After 5 days of intubation under narcosis with forced hyperventilationand diuresis he regained consciousness. During this period blood and urine were collected and TRI and its metabolites werequantified. The highest concentration of TRI in blood was detected13 h after ingestion. Trichloroethanol and trichloroacetic acid,metabolites of the cytochrome P450-mediated pathway, and N-acetyi-S-{l,2-dichlorovinyl)-L-cysteineand N-acetyl-S-(2,2-dichloro-vinyl)-L-cysteine from the glutathione-dependentpathway of TRI were quantified in urine samples. Besides theseknown metabolites in humans, chloroacetic acid and dichloroaceticacid were identified for the first time in urine of a humanexposed to TRI. Although the patient exhibited normal levelsof glucose and total protein in urine, excretion of  相似文献   
98.
A randomized controlled trial (RCT) is the most definitive tool for evaluation of the effectiveness of an intervention and can establish a cause-and-effect relationship between an intervention and an improved disease outcome. However, the undertaking of an RCT does not guarantee valid results, and the findings of RCTs of the same intervention are often discrepant. While many reported trials are of high quality, a significant number have deficiencies in design, conduct, analysis, or interpretation of results. Medical practitioners must become familiar with the methodology of RCTs in order to assess the validity of the reported findings and the relevance of the results to their own patients. Trialists must report sufficient information about the methods used so that readers can judge for themselves if the trial worked as planned. J. Clin. Apheresis 12:130–139, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
99.
The purpose of the present study was to determine the maximum-tolerated doses (MTDs) and the dose-limiting toxicities of a metronomic administration of oral vinorelbine and cisplatin in patients with advanced/metastatic NSCLC. Twenty-six patients with advanced/metastatic NSCLC were enrolled. Escalating doses of vinorelbine (40–70 mg p.o./trice per week) and cisplatin (70–85 mg/m2 intravenous infusion) were administered on day 1 every 3 weeks. ΜΤDs were reached at 60 mg thrice/week p.o. for vinorelbine and 85 mg/m2 for cisplatin. Grade 4 neutropenia, febrile neutropenia and grade 4 diarrhea were the dose-limiting events during the first cycle of chemotherapy. The most common grade III-IV hematologic toxicity was neutropenia occurring in seven (27%) patients, while non-hematological toxicities were relatively infrequent and mostly of grade I or II. Objective responses were observed in 20.8% of patients with measurable disease. The regimen of metronomic administration and cisplatin is feasible and active in patients with NSCLC.  相似文献   
100.
Micropapillary carcinomas (MPCs) can present as a rare histological special type of breast cancer; however, this histological type is more frequently found admixed with invasive ductal carcinomas of no special type (IDC‐NSTs). We have previously demonstrated that pure MPCs constitute a distinct entity at the morphological and genetic levels. Here, we sought to determine whether mixed MPCs have genomic aberrations similar to those found in pure MPCs, and to investigate whether the distinct morphological components of MPCs harbour different genetic aberrations. Using high‐resolution microarray comparative genomic hybridization (aCGH), we profiled a series of 10 MPCs of mixed histology and 20 IDC‐NSTs matched for grade and oestrogen receptor (ER) status. In addition, we generated tissue microarrays containing a series of 24 pure and 40 mixed MPCs and performed immunohistochemical analysis with ER, progesterone receptor (PR), Ki‐67, HER2, cytokeratin (CK) 5/6, CK14, CK17, EGFR, topoisomerase‐IIα, cyclin D1, caveolin‐1 and E‐cadherin antibodies. In situ hybridization was employed to evaluate the prevalence of HER2, TOP2A, EGFR, CCND1, MYC and FGFR1 gene amplification. Our results demonstrate that mixed MPCs harbour similar patterns of genomic aberrations and phenotype (82.5% luminal and 17.5% HER2) compared to pure MPCs. A comparison between the distinct morphological components of mixed MPCs in a pairwise fashion revealed that both components harbour strikingly similar genomic profiles. When compared to grade‐ and ER‐matched IDC‐NSTs, mixed MPCs significantly more frequently harboured amplification of multiple regions on 8q (adjusted Fisher's p value < 0.05). Furthermore, mixed MPCs displayed higher proliferative rates than grade‐ and ER‐matched IDC‐NSTs. Our results suggest that micropapillary differentiation in breast cancer may identify a subgroup of more aggressive ER‐positive breast carcinomas, even in those featuring a mixed histology, and that mixed MPCs are more closely related to pure MPCs than to IDC‐NSTs. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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