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931.
目的研发一种专用于防旋型股骨近端髓内钉置入时的三维导航器。方法选取颈干角为(135±5)°,并且股骨大转子顶点基本与股骨头中心等高的人体股骨骨骼的干标本32例,其中左侧16例,右侧16例。通过股骨头中心、平行于股骨干、垂直于股骨干与股骨颈所在的平面用钢锯将股骨标本的股骨头进行截骨;在股骨大粗隆顶端开口向股骨近端髓腔内插入PFNA主钉,主钉钉尾与股骨头中心点在同一高度上。在本课题所研发的股骨近端髓内钉三维导航器的导引下向股骨头颈部打入动力钉导引针,测量动力钉导引针在股骨头截骨面上的出针点与经股骨头中心点直线的垂直距离作为偏离值。结果利用本课题所研制的三维立体导航器在32例股骨骨骼的干标本上置入导引针,其中14例偏离值为0(占43.75%),最大偏离值为2mm,仅3例(占9.375%),平均误差只有0.69mm。结论本课题所研制的导航器结构简单,操作简便,定位精确,值得进一步在临床上研究应用。  相似文献   
932.
The glutathione-coated CdTe quantum dots (QDs) were synthesized in a paper. After purification, the QDs were coupled with monoclonal antibody to fight against fenvalerate. The conjugates had the same emission wavelength as that of QDs. The excitation wavelength and emission wavelength of the conjugates were determined to obtain the highest signal-to-noise ratio. After the antibody concentration optimization, the fluorescence-linked immunoassay method was developed. The method used the QDs as the signal to quantify the fenvalerate. Compared with the enzyme-linked immunosorbent assay (ELISA), it saved more than 1 h and decreased the false-positive rate using the specified emission wavelength of QDs. The 50% inhibitory concentration (IC50) of the method was 0.28 µg mL?1. The detection limit was 25 ng mL?1 and the linear range was 60 ng mL?1–3.83 µg mL?1. Via preliminary application, fenvalerate residues in spiked samples were determined. The recovery of fenvalerate in water samples ranged from 84.5% to 96.2% and that in vegetables ranged from 72.5% to 125.7%. It was a rapid detection of the fenvalerate residue in environment and vegetables.  相似文献   
933.
934.
A young gentleman presented with difficulty in breathing. Computed tomography (CT) scan showed a huge mass located between the heart and stomach, which might have rooted in the diaphragm. Magnetic resonance imaging (MRI) with enhanced three dimensional construction showed a lobulated, heterogeneous soft tissue mass with short T1 weighted imaging signal and flake long T2-weighted imaging (T2WI). Tumor-enhanced scanning demonstrated heterogeneous contrast enhancement. The preliminary diagnosis was intra-abdominal huge mass and considering sarcoma. Resection was conducted where the base of the tumor was located in the diaphragm oppressing the left liver lobe and heart. The base of the tumor, together with partial surrounding of the diaphragm, pericardium base, and the left lateral hepatic segment, was resected. The defect in the diaphragm and pericardium was repaired by patching, and thoracic close drainage and abdominal drainage were placed following the surgical operation. The pathological report showed giant solitary fibrous tumor (SFT). This case report may provide a reference resource for the diagnosis and treatment of SFT located in the diaphragm.  相似文献   
935.
This report documents a case of isolated adrenal gland cryptococcosis without the often reported component of concomitant meningitis or Addison's disease in an immune competent patient. Furthermore, both the patient's lung cancer and adrenal infection with cryptococcus were incidentally discovered during work‐up for syncope in the setting of hyponatremia. This case also underscores the diagnostic value of fine‐needle aspiration biopsy in this unusual presentation. Diagn. Cytopathol. 2014;42:899–901. © 2014 Wiley Periodicals, Inc.  相似文献   
936.
Background: Transforming growth factor‐β3 (TGF‐β3) plays a central role in mediating secondary palate fusion along the facial midline. However, the mechanisms by which TGF‐β3 functions during secondary palate fusion are still poorly understood. Results : We found that mouse cytokeratin 6α and 17 mRNAs were expressed exclusively in the palate medial edge epithelium on embryonic day 14.5, and this expression was completely abolished in Tgf‐β3 mutant embryos. In contrast, we found that Jagged2 was initially expressed throughout the palate epithelium, but was specifically down‐regulated in the medial edge epithelium during palatal fusion. Jagged2 down‐regulation was regulated by TGF‐β3, since Jagged2 was persistently expressed in palatal medial edge epithelium in Tgf‐β3 null mutant embryos. Moreover, addition of DAPT, a specific inhibitor of Notch signaling, partially rescued the fusion defects in Tgf‐β3 null mutant palatal shelves. Conclusions : Based on these results, together with the previous study indicating that the loss of Jagged2 function promotes embryonic oral epithelial fusion, we concluded that TGF‐β3 mediates palate fusion in part by down‐regulating Jagged2 expression in palatal medial edge epithelium. In addition, cytokeratin 6α and 17 are two TGF‐β3 downstream target genes in palate medial edge epithelium differentiation. Developmental Dynamics 243:1536–1543, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
937.
Thermosensitive hydrogels based on chitosan are of great interests for injectable implant drug delivery. The poly(ethylene glycol)-grafted-chitosan (PEG-g-CS) hydrogel was reported as a potential thermosensitive system. The objective of the present study is to evaluate the cytotoxicity, in vivo degradation and drug release of PEG-g-CS hydrogel. Cytotoxicity was evaluated using L929 murine fibrosarcoma cell line. Degradation and drug release in vivo were investigated by subcutaneous injection of the hydrogel into Sprague-Dawley rats. PEG-g-CS polymer exhibits no significant cytotoxicity when its concentration is less than 3 mg mL?1. After being implanted, PEG-g-CS hydrogel maintains its integrity for two weeks and collapses, merging into the tissue, in the third week. It causes moderate inflammatory response but no fibrous encapsulation around the hydrogel is found. The hydrogel presents a three-week sustained release of cyclosporine A with no significant burst release in vitro and produces the effective drug concentration in blood for more than five weeks in vivo, performing almost the same bioavailability to chitosan/glycerophosphate hydrogel. Further modifications of PEG-g-CS hydrogel might be necessary to modulate the degradation and to mitigate the fluctuations in blood drug concentration.  相似文献   
938.
939.
Previously, we demonstrated that Tim-1-Fc prevents acute cardiac graft rejection by inhibiting Th1 response. In the present report, we tackled the impact of Tim-1-Fc on Th17 cells in a model of cardiac chronic rejection. Administration of Tim-1-Fc did not result in a detectable impact on innate immunity and regulatory T cells, while it provided protection for Bm12-derive cardiac grafts against chronic rejection in B6 recipients, as manifested by the reduction of inflammatory infiltration along with less severity of vasculopathy. Studies in T-bet-/- recipients by implanting Bm12-derived cardiac grafts further revealed that Tim-1-Fc significantly protected cardiac grafts from chronic rejection along with attenuated production of IL-17 producing T cells. Depletion of CD4 and CD8 T cells or blockade of IL-17 in T-bet-/- recipients demonstrated that Tim-1-Fc selectively suppresses Th17 differentiation along with attenuated IL-17 secretion. Together, our data suggest that Tim-1-Fc protects cardiac grafts from chronic rejection by suppressing CD4 Th17 development and functionality. Therefore, Tim-1-Fc might be a potential immunosuppressive agent in the setting of cardiac transplantation.  相似文献   
940.
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