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71.
A new internal distraction device, comprising a square-bodied bow, a transport plate, a traction mechanism, and two stabilisers, was developed to allow transportation of bone around an arc. Eight adult goats were studied. A curved mandibulectomy 3cm long was made on the mandibular angle. The distractor was implanted to restore the defect. The bone was distracted at a rate of 1mm per day after a 5-day latent period. Distraction lasted 25 to 32 days. Curvilinear distraction was successful in six of the eight goats. After consolidation periods of four or eight weeks, smooth curved bone masses were restored in the distracted areas. Radiographically, there was considerable bone density in the distraction area and opaque columns streamed in the direction of distraction. Histological examination showed membranous bony regeneration in the restored bone. These results suggest that restoration of curved bone defects using the new internal transport distraction device was feasible in goats.  相似文献   
72.
目的:采用有限元的方法建立上颌磨牙根管系统的三维有限元模型。方法:采用Micro-CT扫描,应用Mimics8.1、Geomagic studio8、Unigraphics NX及Ansys9.0等逆向工程软件分别得到上颌第一磨牙根管系统三维外形、实体模型和有限元模型。结果:重建了根管系统的三维有限元模型,网格质量好,具有高度的精确度,并由此证实模型的可行性。结论:将Micro-CT扫描技术、数字图像处理技术与有限元方法结合起来,建立出高精度的上颌第一磨牙根管系统的三维有限元模型,为口腔生物力学提供了研究手段。  相似文献   
73.
The aim of the present study was to describe the clinical, biological and the chest-X ray presentations of newly diagnosed pulmonary tuberculosis. A retrospective study of 200 patients was performed from January to October 2004 in the respiratory diseases unit of Dakar's University Teaching Hospital. Among the 200 cases, 140 (70%) were male, giving a sex ratio of 2.3. The mean age of our patients was 35.5 years (range: 14-81 years). The group age of 20 to 39 years was the most affected (55,5% of patients). The median diagnostic delay was 4 months (range: 7 days to 2 years). Haemoptysis revealed the disease in 27% of cases. The chest X-ray showed bilateral lesions in 65% of cases. When they were unilateral, the right side was the most concerned. Of the 200 patients, the lesions interested all parts of at least one lung in 106 (53%). Among our patients, 153 (76.5%) had cavitations and 145 (72.5%) had infiltrates. A pleural effusion was associated to the lung lesions in 10% of the patients. Biologically, we reported 80% cases (n=160) of hypochromic microcytic anaemia. Of the 27 HIV tests done, 18 (66.7%) were positive all for HIV1. Delay in the diagnosis of pulmonary tuberculosis was very long and our data illustrate the need for improved education of the community and event of healthcare workers about the benefit of early diagnosis of tuberculosis.  相似文献   
74.
In many human diseases, the presence of inflammation is associated with an increase in the level of reactive oxygen species (ROS). The resulting state of oxidative stress is highly detrimental and can initiate a cascade of events that ultimately lead to cell death. Thus, many therapeutic attempts have been focused on either modulating the immune system to lower inflammation or reducing the damaging caused by ROS. Berlin et al. reported the development of a novel nanoantioxidant known as poly(ethylene glycol)‐functionalized‐hydrophilic carbon clusters (PEG‐HCCs). They showed that PEG‐HCCs could be targeted to cancer cells, utilized as a drug delivery vector, and can even be visualized ex vivo. Our work here furthers this work and characterizes Gd‐DTPA conjugated PEG‐HCCs and explores the potential for in vivo tracking of T cells in live mice. We utilized a mouse model of delayed‐type hypersensitivity (DTH) to assess the immunomodulatory effects of PEG‐HCCs. The T1‐agent Gd‐DTPA was then conjugated to the PEG‐HCCs and T1 measurements, and T1‐weighted MRI of the modified PEG‐HCCs was done to assess their relaxivity. We then assessed if PEG‐HCCs could be visualized both ex vivo and in vivo within the mouse lymph node and spleen. Mice treated with PEG‐HCCs showed significant improvements in the DTH assay as compared to the vehicle (saline)‐treated control. Flow cytometry demonstrated that splenic T cells are capable of internalizing PEG‐HCCs whereas fluorescent immunohistochemistry showed that PEG‐HCCs are detectable within the cortex of lymph nodes. Finally, our nanoantioxidants can be visualized in vivo within the lymph nodes and spleen of a mouse after addition of the Gd‐DTPA. PEG‐HCCs are internalized by T cells in the spleen and can reduce inflammation by suppression of a recall immune response. PEG‐HCCs can be modified to allow for both in vitro and in vivo visualization using MRI. © 2016 The Authors. NMR in Biomedicine published by John Wiley & Sons Ltd.  相似文献   
75.

Purpose

In humans, the styloauricularis is a rare muscle extending from the tragal cartilage of the auricle to the styloid process. When it contracts, by bearing on the styloid process, it increases the cephalo-auricular angle. It can be a landmark for the facial nerve. We report a case with bilateral presence of the styloauricularis.

Methods

Bilateral presence of the styloauricularis was discovered during routine dissection of the head and neck.

Results

In the presented case, styloauricularis muscles arose from the cartilage of the external acoustic meatus on both sides of the head, crossing halfway along the facial nerve trunk and inserting the styloid process. Both muscles were vascularized by a branch of the posterior auricular artery, and innervated by the facial nerve.

Conclusions

The ventral auricular muscle, formed by the auricular parotid and the styloauricular muscles, is a muscle that lowers and abducts the auricle in animals. There is generally considered to be no equivalent for these muscles in humans, however, this bilateral case reveals evidence to the contrary. There is a dearth of scientific literature about the styloauricularis. The study of this muscle demonstrated the usefulness of comparative anatomy in understanding its action in increasing the cephalo-auricular angle.
  相似文献   
76.
Our objectives were to describe hemato-immunological abnormalities encountered in tuberculosis patients HIV seropositive (TBVIH+, n = 67) or not (TBVIH-, n = 39) and in HIV asymptomatic patients (aSVIH+, n = 40). We found: a great reduction of mean value of RBC and Hb in TBVIH+ and TBVIH-; a reduction of mean value of leucocytes, total lymphocytes and CD4+ lymphocytes in TBVIH+ and aSVIH+; an inversion of [formula: see text] ratio, more important in TBVIH+ than in aSVIH+. HIV and tuberculosis association, HIV1 serotype and CD4 < 200/mm3 were found to promote significantly hemato-immunological abnormalities.  相似文献   
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