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排序方式: 共有2057条查询结果,搜索用时 15 毫秒
111.
Use of fibrin sealant for prosthetic mesh fixation in laparoscopic extraperitoneal inguinal hernia repair 总被引:18,自引:0,他引:18
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Katkhouda N Mavor E Friedlander MH Mason RJ Kiyabu M Grant SW Achanta K Kirkman EL Narayanan K Essani R 《Annals of surgery》2001,233(1):18-25
OBJECTIVE: To evaluate the efficacy of mesh fixation with fibrin sealant (FS) in laparoscopic preperitoneal inguinal hernia repair and to compare it with stapled fixation. SUMMARY BACKGROUND DATA: Laparoscopic hernia repair involves the fixation of the prosthetic mesh in the preperitoneal space with staples to avoid displacement leading to recurrence. The use of staples is associated with a small but significant number of complications, mainly nerve injury and hematomas. FS (Tisseel) is a biodegradable adhesive obtained by a combination of human-derived fibrinogen and thrombin, duplicating the last step of the coagulation cascade. It can be used as an alternative method of fixation. METHODS: A prosthetic mesh was placed laparoscopically into the preperitoneal space in both groins in 25 female pigs and fixed with either FS or staples or left without fixation. The method of fixation was chosen by randomization. The pigs were killed after 12 days to assess early graft incorporation. The following outcome measures were evaluated: macroscopic findings, including graft alignment and motion, tensile strength between the grafts and surrounding tissues, and histologic findings (fibrous reaction and inflammatory response). RESULTS: The procedures were completed laparoscopically in 49 sites. Eighteen grafts were fixed with FS and 16 with staples; 15 were not fixed. There was no significant difference in graft motion between the FS and stapled groups, but the nonfixed mesh had significantly more graft motion than in either of the fixed groups. There was no significant difference in median tensile strength between the FS and stapled groups. The tensile strength in the nonfixed group was significantly lower than the other two groups. FS triggered a significantly stronger fibrous reaction and inflammatory response than in the stapled and control groups. No infection related to method of fixation was observed in any group. CONCLUSION: An adequate mesh fixation in the extraperitoneal inguinal area can be accomplished using FS. This method is mechanically equivalent to the fixation achieved by staples and superior to nonfixed grafts. Biologic soft fixation with FS will prevent early graft migration and will avoid the complications associated with staple use. 相似文献
112.
113.
Rajesh P Rajesh R Narayanan V Baig MF Prabhu VR Venkatesan A 《Journal of the Indian Society of Pedodontics and Preventive Dentistry》2000,18(4):147-150
Cleft lip and palate is one of the most common malformations in man. Although the subject of a great deal of investigation, etiologic factors contributing to these congenital deformities remain largely unknown. Various factors like race, sex, parental age at the time of conception etc. have been listed as the exogenous factors. This article strives to project any significant relationship of these factors to cleft lip and cleft palate. 相似文献
114.
115.
S Zaman B Carlsson A Morikawa S Jeansson I Narayanan K Thiringer F Jalil L A Hanson 《Archives of disease in childhood》1993,68(2):198-201
Varying titres of secretory IgA antibodies to poliovirus type 1 were found previously in the milk of unvaccinated, lactating Pakistani mothers during two different years, reflecting the antigenic exposure on mucosal membranes. To study further the changes in the extent and the form of antigenic exposure reflected in the human milk, human milk samples from Pakistani, Indian, Japanese, and Swedish mothers were collected. The quality and the neutralising capacity of the antibodies was also studied. Secretory IgA, IgG, and IgM antibodies to poliovirus type 1 were determined using enzyme linked immunosorbent assay (ELISA) and relative affinity was measured in ELISA by elution with potassium thiocyanide. Microneutralisation tests were also performed. The higher secretory IgA antibody titres to poliovirus type 1 in the unvaccinated, naturally exposed Pakistani and Indian mothers' milk, compared with the Swedish and Japanese mothers, presumably reflect the epidemiological situation in these countries. Neutralising capacity and the relative antibody affinity seemed to be higher both in the Pakistani mothers and the group without natural exposure but only given inactivated poliovirus vaccine, that is the Swedish mothers, than the group meeting only live vaccine strains, that is the Japanese mothers. 相似文献
116.
The development of certain human cancers has been linked with inadequate intake of folates. The effects of folate deficiency in vivo on DNA stability (strand breakage, misincorporated uracil and oxidative base damage) in lymphocytes isolated from rats fed a diet deficient in folic acid was determined. Because the metabolic pathways of folate and other methyl donors are closely coupled, the effects of methionine and choline deficiency alone or in combination with folate deficiency were determined. Feeding male Hooded Lister rats a folate-free diet for 10 weeks created a moderate folate deficiency (25-50% (approx.) decrease in plasma, red blood cell and hepatic folate concentrations (P < 0.05) and a 20% rise in plasma homocysteine (P < 0.05)). Lymphocyte DNA strand breakage was increased successively in all groups after 4 weeks and 8 weeks on the diet (50-100% (approx.) after 8 weeks). Only low folate specifically and progressively induced uracil misincorporation throughout the study (100% (approx.) after 8 weeks). Neither folate deficiency nor choline/methionine deficiency altered oxidative DNA base damage. In summary, moderate folate deficiency in vivo is associated with a decrease in DNA stability, measured as increased DNA strand breakage and misincorporated uracil. 相似文献
117.
Diminished DNA repair and elevated mutagenesis in mammalian cells exposed to hypoxia and low pH 总被引:10,自引:0,他引:10
The tumor microenvironment is characterized by regions of fluctuating and chronic hypoxia, low pH, and nutrient deprivation. It has been proposed that this unique tissue environment itself may constitute a major cause of the genetic instability seen in cancer. To investigate possible mechanisms by which the tumor microenvironment might contribute to genetic instability, we asked whether the conditions found in solid tumors could influence cellular repair of DNA damage. Using an assay for repair based on host cell reactivation of UV-damaged plasmid DNA, cells exposed to hypoxia and low pH were found to have a diminished capacity for DNA repair compared with control cells grown under standard culture conditions. In addition, cells cultured under hypoxia at pH 6.5 immediately after UV irradiation had elevated levels of induced mutagenesis compared with those maintained in standard growth conditions. Taken together, the results suggest that cellular repair functions may be impaired under the conditions of the tumor microenvironment, causing hypermutability to DNA damage. This alteration in repair capacity may constitute an important mechanism underlying the genetic instability of cancer cells in vivo. 相似文献
118.
Cancer gene discovery using digital differential display 总被引:24,自引:0,他引:24
Scheurle D DeYoung MP Binninger DM Page H Jahanzeb M Narayanan R 《Cancer research》2000,60(15):4037-4043
119.
120.
S Narayanan 《Annals of clinical and laboratory science》1991,21(1):12-18
A perspective on serum alkaline phosphatase isoenzymes in liver disease is provided with a brief discussion of the location of the enzyme in liver and its presumed function. Mechanisms of entry of alkaline phosphatase into serum in liver disease are discussed. Characterization of high molecular weight alkaline phosphatase in obstructive jaundice is reviewed. The relationship between blood group O and the appearance of the intestinal enzyme in sera of such subjects with cirrhosis of liver is discussed. Properties of hepatoma alkaline phosphatase and the genesis of liver alkaline phosphatase in diseases not related to the liver are explored. Methods for detection of serum alkaline phosphatase isoenzymes in liver disease are discussed from the standpoint of the limitations of electrophoretic procedures, and the promise of procedures such as isoelectric focusing and high performance liquid chromatography that are currently non-routine. 相似文献