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51.
Heister introduced a mouth gag of incentric pattern which is still being used. Heister jaw opener has narrow blades which rest on the occlusal surface of molar teeth. The force of mouth gag is not equally distributed on all the teeth, therefore there is great risk of tooth avulsion in periodontally compromised dentition and fracture of tooth while using standard Heister appliance. To overcome this modification of Heister mouth gag is done.  相似文献   
52.
Surgical repair of acquired tracheo-esophageal fistula may result in tracheal stenosis or esophageal stricture. We used fistula with esophageal cuff as flap to repair the tracheal defect. Esophageal repair was performed by rotating ends through 90° in opposite direction. This technique offers excellent repair in a single stage.  相似文献   
53.
BACKGROUND CONTEXT: Pseudoarthrosis rates in lumbar intertransverse fusion remain high. Compression and displacement of the developing fusion mass by the paraspinal musculature may be a contributory factor. Biocontainment devices have been clinically used in the skull and mandible to guide bone regeneration. The role of a mechanical device in containing graft material in the developing posterolateral lumbar spine fusion is unclear. PURPOSE: To determine the benefits of using a bioabsorbable graft-containment device for lumbar intertransverse fusion, and to evaluate the biocompatibility of this implant by histological analysis of the host tissue reaction. STUDY DESIGN: A rabbit intertransverse spine fusion model was used to evaluate a bioabsorbable graft-containment implant. Study and control groups were compared with regard to the rate, volume, and quality of fusion, as well as host tissue reaction to the graft and implant. METHODS: Fourteen adult male New Zealand White rabbits underwent bilateral posterolateral intertransverse spine arthrodesis at L3-L4. The control group (n=7) received autograft alone, and the study group received autografts placed in open meshed hemicylinders fashioned from LactoSorb sheets (LactoSorb; Biomet Orthopedics Inc., Warsaw, IN). Spines were harvested at 6 weeks and imaged. Radiographs and computed tomography (CT) images were used to calculate the rate, area, and volume of fusion mass. Sections were fixed and stained with hematoxylin-eosin and Mallory trichrome for histological analysis of fusion and host tissue response. The Mann-Whitney nonparametric statistical test was used for the radiographic and CT qualitative assessments. The CT volume quantitation was analyzed using the Student t test. A p value of <.05 was used to assign statistical significance. RESULTS: The fusion rates on radiographs and CT imaging did not show a significant difference (p>.05) between the biocontainment and control groups. The volume of fusion revealed a significant increase with biocontainment (mean+/-standard error; total left+right fusion sides=2.88+/-0.30 cc) compared with controls (2.12+/-0.15 cc) (p<.05). Histology revealed no difference in the maturity or the quality of the fusion mass between the two groups. Inflammatory response around the developing fusion mass and muscle necrosis were slightly increased in the study group. The LactoSorb biocontainment material led to variable inflammatory reaction, with some areas showing little or no response and other showing an inflammatory response with fibrous connective tissue, lymphocyte infiltration, and focal foreign body giant cell reaction. CONCLUSIONS: The incidence of fusion was similar with or without a containment device for onlay bone graft. A significant increase in the volume of the fusion suggests that a biocontainment device does play a role in protecting the developing fusion mass from the mechanical effects of the paraspinal musculature. The clinical use of this device cannot be justified at this time, and further studies will determine whether this increase in fusion volume will translate into a better incidence and volume of fusion in primate and human models.  相似文献   
54.
A 65-year-old man with a 5.5 x 3.2-cm stage T(2)N(0)M(0) grade III renal-cell carcinoma suffered a port-site metastasis 8 months after laparoscopic radical nephrectomy with specimen removal in an organ-retrieval bag. This case underlines the need to be conversant with, and care to avoid, risk factors for this complication.  相似文献   
55.
Schneider WM  Wu DT  Amin V  Aiyer S  Roth MJ 《Virology》2012,426(2):188-196
For Moloney murine leukemia virus (M-MuLV), sustained viral infections require expression from an integrated provirus. For many applications, non-integrating retroviral vectors have been utilized to avoid the unwanted effects of integration, however, the level of expression from unintegrated DNA is significantly less than that of integrated provirus. We find that unintegrated DNA expression can be increased in the presence of HDAC inhibitors, such as TSA, when applied in combination with integrase (IN) mutations. These mutants include an active site mutation as well as catalytically active INs bearing mutations of K376 in the MuLV C-terminal domain of IN. MuLV IN K376 is homologous to K266 in HIV-1 IN, a known substrate for acetylation. The MuLV IN protein is acetylated by p300 in vitro, however, the effect of HDAC inhibitors on gene expression from unintegrated DNA is not dependent on the acetylation state of MuLV IN K376.  相似文献   
56.

Background

The production of a copy of the fracture or a deformity in a bone with a complex geometry can be one of the important applications of the integration between two modern computer-based technologies, reverse engineering (RE) and rapid prototyping (RP).

Methods

This article reviews recent development in this field and present a case series about the use of medical CT/MRI scanning, three-dimensional reconstruction, anatomical modeling, computer-aided design, RP and computer-aided implantation in treating a complex fracture of acetabulums, calcaneum, and medial condyle of femur (Hoffa's fracture).

Conclusion

The use of RP technology helped us to understand the fracture configuration and to achieve near anatomical reduction. With this we believe, this technology will reduce the surgical time as was observed in our cases. This consequently, will lower the requirement of an anesthetic dosage and decrease the intraoperative blood loss.In summary, the merging of computational analysis, modeling, designing, and fabrication will serve as important means to treat conditions and fractures around joints, spine, acetabulum, and craniofacial region.

Level of evidence

Level 4, case series.  相似文献   
57.
ObjectiveThe aim of the present study was to estimate the prevalence of dental caries in the primary dentition of kindergarten school children of Udaipur city Rajasthan in a cross sectional study design.Materials and methodsStudy population comprised of around 355 children aged 3–6 years old randomly selected from 10 kindergarten schools in Udaipur city from all preselected five zones. Dental caries was recorded using the decayed, missing, filled teeth [dmf-t] index and the decayed, missing, filled surfaces [dmf-s] index according to WHO 1997 standards.ResultsSeventy-nine point one five percent are caries free individuals while 20.85% are individuals having caries. The mean dt scores for the age group six is found to be highest with 0.45 (0.86) and least for the age group of four with 0.28 (0.74). Sixty-five point six three percent of the subjects brushed their teeth by themselves while 34.37% do it with the help of their mothers.ConclusionDental caries prevalence and severity is low among the students.  相似文献   
58.
Transitional cell carcinoma of urinary bladder (TCCUB) usually presents with hematuria. Cerebral and leptomeningeal metastases as a first manifestation of TCCUB have been occasionally reported in the medical literature. Hence, we report a case of an elderly man who presented with localizing neurological signs and whose magnetic resonance imaging brain showed multifocal cerebral and leptomeningeal lesions suspected to be metastatic deposits. Thorough search for the primary tumor revealed TCCUB.  相似文献   
59.
Purpose To evaluate the utility of selective esophageal manometry in clinical practice. Results Retrospective data from 200 subjects was reviewed. Manometry was considered to be (1) high clinical utility when specific abnormality was identified resulting in therapeutic intervention, (2) low clinical utility when specific abnormality was identified without alteration of therapy, (3) limited clinical utility when manometry was normal. High, low, and limited clinical utility was noted in 47, 40, and 13% of instances. Manometry was of high utility in patients with dysphagia or non-cardiac chest pain (P < 0.05), and low utility in gastroesophageal reflux (P < 0.05). Conclusions (1) Esophageal manometry has high clinical utility in dysphagia after exclusion of structural disorders; and non-cardiac chest pain after careful exclusion of reflux. (2) Ineffective motility disorder has high association with gastroesophageal reflux disease but low clinical utility except in preoperative assessment for fundoplication. (3) Esophageal manometry is of high utility in clinical practice when used in conjunction with other diagnostic exclusions.  相似文献   
60.
Dubey V  Mishra D  Asthana A  Jain NK 《Biomaterials》2006,27(18):3491-3496
Melatonin (MT) is a good candidate for transdermal delivery considering its short biological half-life, low molecular weight and a variable oral absorption. The objective of this work was to develop a novel formulation of melatonin for its efficient transdermal delivery. Melatonin loaded elastic liposomal formulation was prepared, characterized and the effect of this developed formulation on the in vitro permeation of melatonin across human cadaver skin was investigated, using a locally fabricated Franz diffusion cell. Skin permeation potential of the developed formulation was assessed using confocal laser scanning microscopy (CLSM), which revealed an enhanced permeation of the formulation to the deeper layers of the skin (up to 180 microm) following channel like pathways. Skin permeation profile of melatonin through elastic liposomal formulations was observed and the investigations revealed an enhanced transdermal flux (51.2+/-2.21 microg/cm(2)/h), decreased lag time (1.1h) and an optimum permeability coefficient (15.06+/-0.52 cm/h) for melatonin. The obtained flux was nearly 5 and 12.3 times higher than conventional liposomal and plain drug solution, respectively (P<0.005). Our result suggests the feasibility of elastic liposomal system for transdermal delivery of melatonin thereby eliminating the limitations of long lag time and poor skin permeation associated with the drug.  相似文献   
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