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21.
Herein is described cortical bone trajectory (CBT), a new path for pedicle screw insertion for lumbar vertebral fusion. Because the points of insertion are under the end of the inferior articular process, and because the screws are inserted toward the lateral side, there is less soft tissue development than with the conventional technique; the CBT technique therefore enables less invasive surgery than the conventional technique. However, it has some drawbacks. For example, in the original CBT approach, the points of insertion are in the vicinity of the end of the inferior articular process. Because this joint has been destroyed in many patients who have indications for intervertebral fusion surgery, it is sometimes difficult to use it as a reference point for screw insertion location. With severe lateral slippage, the screw insertion site can become significantly dislocated sideways, with possible resultant damaging to the spinal canal and/or nerve root. The CBT technique here involved inserting the screws while keeping clear of the intervertebral foramen with the assistance of side view X‐ray fluoroscopy and using the end of the inferior articular process and the isthmus as points of reference for screw location.  相似文献   
22.
Objectives: To examine the association between cancer location, resection margins and oncological outcome in patients undergoing radical prostatectomy. Methods: A total of 505 patients who underwent radical prostatectomy between 1993 and 2009 were included in this analysis. Cancer location, resection margins and pathological factors were assessed based on the 2010 General Rules for Clinical and Pathological Studies on Prostate Cancer. Biochemical recurrence was defined as prostate‐specific antigen >0.2 ng/mL. Results: Positive resection margins were found in 38.4% of all cases, in 30.3% of pT2 cases and in 57.7% of pT3 cases. The cancer was distributed evenly among the apex‐anterior, apex‐posterior and middle lesions, which each accounted for approximately 30% of the whole lesion in the main tumor. A higher rate of positive resection margins (47.6%) was found in the apex‐anterior lesions. In minor tumors, most cancer was located in the middle lesion and accounted for approximately 60% of the lesion. However, positive resection margins were detected significantly more frequently in the apex‐anterior lesion of minor tumors. The 5‐year and 10‐year biochemical recurrence‐free survival rates were 36.2% and 32.0%, respectively, in patients with a positive resection margin, and 82.7% and 77.4%, respectively, in those with a negative resection margin. Cancer location was an independent risk factor for biochemical recurrence and a positive resection margin. Recurrence‐free survival was lower in pT2 cases with a positive resection margin compared with pT3 cases with a negative resection margin. Conclusions: Cancer location and occurrence of positive resection margins can have negative effects on recurrence‐free survival. Thus, it is of utmost importance to avoid positive resection margins during radical prostatectomy.  相似文献   
23.

Purpose  

Laparoscopic colonic surgery is now widely accepted. We assessed the safety and effectiveness of using a total intracorporeal surgical strategy to perform intracorporeal functional end-to-end anastomosis with an endoscopic linear stapler to treat colon cancer.  相似文献   
24.
Although the ability of the liver to regenerate to a predetermined size after resection made adult-to-adult living donor liver transplantation (LDLT) possible, there is little information regarding the growth regulatory mechanism for a small-for-size graft. Forty-one cases of LDLT were divided into two groups by graft volume to standard liver volume ratio (GV/SLV); small graft group (Group S, GV/SLV<40%, n=16) and non-small graft group (Group NS, GV/SLV>40%, n=25). The regeneration rate (GV at 1 week/harvested GV) and serum levels of hepatocyte growth factor (HGF), transforming growth factor- (TGF-) and transforming growth factor-1 (TGF-1) were compared between two groups. The regeneration rates in Group S were significantly higher than that of Group NS (217±12% and 178±10%, respectively, P<0.01). The serum HGF levels of Group S were significantly higher than those of Group NS on POD 1. The TGF-1 levels of Group S were significantly higher than those of Group NS on POD 3 and 5. The TGF- levels were not different at any time points studied. These results indicate that a small-for-size graft retains the capacity to regenerate faster by modulation of expression pattern of HGF and TGF-1 immediately after LDLT. After the acceleration of the regenerative response by HGF, subsequent elevation of TGF-1 synergistically controls graft size, regulating uncontrolled proliferation of hepatocytes.  相似文献   
25.
We investigated intracellular trafficking of GM1 ganglioside in Niemann-Pick C1 (NPC1)-deficient Chinese hamster ovary cells [NPC1(-) cells] by using cholera toxin (CT) as a probe. Both the holotoxin and the B subunit (CTB) accumulated in GM1-enriched intracellular vesicles of NPC1(-) cells. CTB-labeled vesicles contained the early endosome marker Rab5 but not lysosome-associated membrane protein 2 and were not labeled with either Texas red-transferrin or Lysotracker, indicating that they represent early endosomes. Similarly, CT accumulated in intracellular vesicles of human NPC fibroblasts that contained both Rab5 and early endosomal antigen 1. CTB accumulation in NPC1(-) cells was abolished by expression of wild-type NPC1 but not by mutant proteins with a mutation either in the NPC domain or the sterol-sensing domain. A part of these mutant NPC1 proteins expressed in NPC1(-) cells was localized on CTB-labeled vesicles. U18666A treatment of "knock in" cells [NPC1(-) cells that stably expressed wild-type NPC1] caused CTB accumulation similar to that in NPC1(-) cells, and a part of wild-type NPC1was localized on CTB-labeled vesicles in drug-treated cells. Finally, CT tracer experiments in NPC1(-) cells revealed retarded excretion of internalized toxin into the culture medium and an increase in the intracellular release of A subunits. In accordance with the latter result, CT was more effective in stimulating cAMP formation in NPC1(-) than in wild-type cells. These results suggest that transport of CT/GM1 complexes from the early endosome to the plasma membrane depends on the function of NPC1, whereas transport to the Golgi apparatus/endoplasmic reticulum does not.  相似文献   
26.
Hyaluronidase is one of the most important enzymes in the development of many diseases. In this study, a series of xyloside analogues bearing a triazole and tetrazole at the anomeric position were prepared from xylosylthioureas and evaluated their inhibitory effects on the hyaluronidase. Triazole and tetrazole skeletons were formed via the Hg(OAc)2-mediated desulfurizative cyclization through carbodiimide intermediates. According to in vitro anti-hyaluronidase assay, tetrazole-xylosides having p-chloro- or p-nitro-substitution exhibited the high inhibition rates, whereas the compound having p-trifluoromethyl group on the structure did not show the potency. Our results demonstrated the importance of tetrazole-xylosides as hyaluronidase inhibitors.  相似文献   
27.
The procedure of apheresis in pediatric patients, particularly in those with low weight (body weight<10?kg) presents an important challenge due to particularities of this group. There are no specific guidelines or enough scientific evidence to standardize the practice in this group of patients. In addition to the psychological aspect, the correct calculation of the total blood volume, the extracorporeal volume of the cell separator and an estimated decrease in hematocrit must be considered. Personalized protocols for priming of the apheresis equipment, sufficient blood flow and adequate anticoagulation are essential for patient comfort and therapeutic success. The purpose of this article is to present the results of the national study of apheresis practices in low weight group of children conducted from 2012 to 2018.Protocols and patients’ data collected from various apheresis centers in Argentina were compared with the apheresis protocols around the world. Our protocols and data were similar to those in other countries; however, no detailed and specific guidelines for apheresis practices in this population of patients with unique requirements have been developed to date.  相似文献   
28.
Interfacial interactions governing the interfacial adhesion between cellulose propionate and carbon fibre surface are placed under scrutiny to pave the way towards the development of green cellulose-based carbon fibre reinforced polymers. A range of molecular entities are deposited on the surface by initially grafting aromatic structures with appropriate functions via diazonium species followed by further derivatization of these entities. Cellulose propionate was also bound covalently to the surface via a tosylated derivative invoking its facile nucleophilic displacement reaction with surface-grafted amino functions. Significant increase in interfacial shear strength was obtained for the cellulose propionate-grafted carbon fibre composite as well as for the 4-(aminomethyl)benzene-functionalized sample, in the latter case possible hydrogen bonding took place with the cellulose propionate matrix. Furthermore, the positive effect of a highly lipophilic and yet compact –CF3 substituent was also noted. In order to let the grafted structure efficiently penetrate into the matrix, steric factors, lipophilicity and potential secondary interactions should be considered. It needs to be pointed out that we provide the first synthetic strategy to covalently bind cellulose derivatives to a largely graphitic surface and as such, it has relevance to carbonaceous materials being applied in cellulose-based innovative materials in the future.

Interfacial adhesion of a cellulose propionate/carbon fibre composite is tailored providing a synthetic strategy to bind cellulose derivatives to graphitic surfaces.  相似文献   
29.
30.
Fibrillar collagen plays an essential role in ventricular remodeling, which is a major prognostic factor in various heart diseases. Inflammatory cytokines, including tumor necrosis factor alpha (TNFalpha), have been reported to play a role in various heart diseases and OPC-8212, a quinolinone derivative, has been demonstrated to reduce TNFalpha production. No studies have examined the effects of OPC-8212 on collagen metabolism in connection with inflammatory cytokine and growth factors. Using lipopolysaccharides as a tool to enhance TNFalpha, we examined the effects of OPC-8212 on the expression of type III collagen mRNA [alpha1(III)] in cultured neonatal rat cardiac fibroblasts. We also measured the concentration of TNFalpha and transforming growth factor beta (TGFbeta) in the cultured medium. Northern blot analysis revealed that LPS reduced the expression of alpha1(III) mRNA, and OPC-8212 counteracted this reduction (on average 25% above the reduced level by LPS stimulation). LPS enhanced the TNFalpha concentration in the medium, and OPC-8212 inhibited this enhancement. LPS increased the TGF-beta1 concentration in the cultured medium, while OPC-8212 did not affect this increase. In summary, OPC-8212 counteracted the reduction in type III collagen mRNA expression by LPS accompanied by suppression of the increase in TNFalpha.  相似文献   
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