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排序方式: 共有594条查询结果,搜索用时 15 毫秒
1.
K Junge U Klinge B Klosterhalfen P R Mertens R Rosch A Schachtrupp F Ulmer V Schumpelick 《Journal of investigative surgery》2002,15(6):319-328
Alterations of the extracellular matrix (ECM) with its major component collagen are increasingly discussed as possible risk factors implicated in the development of abdominal-wall herniation. Because of the widespread use of alloplastic meshes for the surgical repair of hernias, an animal study was performed to analyze the influence of various mesh materials on the quantity and quality of collagen deposition. In 60 male Sprague-Dawley rats an abdominal replacement was performed using three different kinds of mesh materials: polyester (PE), a pure polypropylene (PP), and a composite mesh made of polypropylene and polyglactin (PG). A simple fascia suture repair served as control. The count of fibroblasts, the collagen/protein ratio, the type I/III collagen ratio, and the expression of basic fibroblast growth factor (b-FGF) at the interface were analyzed after 7, 21, and 90 days. The ratio of collagen to overall protein (microg/mg) showed significant differences comparing different mesh materials (sham controls 38.44 +/- 16.33 microg/mg, PE 68.5 +/- 23.8 microg/mg, PP 101.6 +/- 32.3 microg/mg, PG 49.6 +/- 11.6 microg/mg at day 90). The ratio of collagen type I/III increased over time in all groups. However, 90 days after mesh implantation the ratio was always significantly lowered compared to the controls. No significant difference was found comparing different mesh materials. The alteration of the scar composition is closely connected to an increased b-FGF expression. b-FGF and count of fibroblasts highly correlated (r =.95) and showed significant elevated levels compared to simple suture repair. The results of our study strongly support the notion that wound healing is affected by mesh implantation. The quality of the ECM deposition as determined by collagen type I/III ratio is impaired in general, whereas the quantity of ECM deposition is markedly influenced by the kind of mesh material. 相似文献
2.
3.
S Isaksson P Alberius B Klinge J J?nsson 《Scandinavian journal of dental research》1992,100(5):274-278
In skeletal surgery, bone chips and bone paste are often used to facilitate bony repair. However, no comparative investigation between these forms of bone graft implantation has been undertaken. In this study four trephine skull defects were produced in each of 14 adult rabbits and inlays of bone paste and two separate amounts of bone chips were then implanted in each animal. The results were compared relative to a control defect and assessed by gross inspection, light microscopy, and contact radiography after periods of 4 and 15 wk. Bone chips offered only minor advantages over controls in the defects investigated and differences in bony regeneration between the diversified amounts of bone chips were negligible. After bone paste implantation, a cellular and mature bone was rapidly produced. The clinical significance of these findings is discussed. 相似文献
4.
Temporary closure of the abdominal wall (laparostomy) 总被引:2,自引:0,他引:2
A. Schachtrupp V. Fackeldey U. Klinge J. Hoer A. Tittel C. Toens V. Schumpelick 《Hernia》2002,6(4):155-162
The definitive closure of the abdominal wall, i.e., a closure of the fascial layer and skin may not be favorable in the treatment
of numerous surgical conditions, e.g., peritonitis, trauma, or mesenteric ischemia. In these cases, the abdominal wall is
temporarily closed, and a laparostomy is created to facilitate re-exploration or to prevent abdominal compartment syndrome.
Regarding the technique and material used for the temporary closure, no prospective randomized data exists, but mesh materials
are commonly used. They provide drainage of infectious material, permit visual control of the underlying viscera, facilitate
access to the abdominal wall, preserve the fascial margin, enable healing by secondary intention, and allow mobilization of
the patient. In the case of decreasing intra-abdominal pressure, meshes can be trimmed to centralize the rectus muscle and
to facilitate definitive closure. Non-absorbable meshes have been frequently reported to cause enteric fistulae and persistent
infection necessitating mesh explantation. While these infectious complications appear to occur less frequently with the use
of absorbable materials, these meshes will finally lead to an incisional hernia, requiring repair with non-absorbable mesh
after a period of 6–12 months. Nevertheless, in the complex situation requiring a temporary abdominal wall closure, use of
absorbable mesh material is common and represents the state of the art.
Electronic Publication 相似文献
5.
R. Rosch P. Lynen-Jansen K. Junge M. Knops B. Klosterhalfen U. Klinge P. R. Mertens V. Schumpelick 《Hernia》2006,10(2):125-130
With regard to the pathogenesis of recurrent incisional hernia, an impaired connective tissue quality leading to an aberrant
scarring process has been proposed. For the matrix metalloproteinase (MMP-2) a pathogenetic involvement in direct inguinal
hernia development is reported. With mesh implantation as the gold standard treatment for incisional hernias, the aim of the
present study was to investigate the MMP-2 expression in patients with recurrent incisional hernias with and without mesh-materials.
In primary fibroblast cultures obtained from skin scars in patients with and without recurrent incisional hernias, MMP-2 synthesis
and gene expression were investigated. Furthermore, MMP-2 synthesis and gene expression of fibroblasts were compared after
incubation with two different mesh materials: polypropylene and absorbable polyglactin filaments. MMP-2 enzyme activity was
determined by semiquantitative zymography and mRNA synthesis by quantitative RT-PCR. Both MMP-2 enzyme activity and mRNA expression
were similar in hernia and control fibroblasts in vitro. In control fibroblasts mesh incubation did not significantly affect
MMP-2 expression, whereas polypropylene mesh contact of fibroblasts from patients with recurrent incisional hernias led to
a major decrease of MMP-2 activity and of mRNA expression. In the absence of biomaterials fibroblasts from recurrent incisional
hernia, patients have no alterations of their MMP-2 synthesis compared to control fibroblasts, whereas a specific response
was found after biomaterial contact hereby indicating differences in fibroblast phenotype.
This work was supported by IZKF-BIOMAT, RWTH-Aachen, project no. TV B66 and by the Deutsche Forschungsgemeinschaft grant KL
1320/2-1 相似文献
6.
In guided tissue regeneration (GTR) procedures, flap recession or sloughing may occur as an unwanted sequel to the placement of a membrane. This study was designed to assess the applicability of laser Doppler flowmetry (LDF) in the evaluation of blood perfusion in the mucoperiosteal flap covering the membrane. Five Labrador dogs were initially used inthe study, but one animal was later excluded due to post‐operative problems. Maxillary premolar teeth were extracted and full thickness mucoperiosteal flaps were raised. Following removal of the buccal bone plate, 4 titanium implants were placed on each side. An experimental biodegradable polylactic‐acid membrane was placed over the fixtures on one side to allow for GTR. The mucoperiosteal flap was repositioned and secured with sutures. The contralateral side served as control with no membrane. Blood perfusion was measured in the flaps before surgery, immediately after suturing and at 24, 48 and 72 h postoperatively. A laser Doppler flowmeter was used to assess the blood perfusion. In 3 animals the membrane was exposed within 2 weeks post‐operatively, and in these 3 animals the LDF values were lower on the membrane side than on the control side. The mean LDF value was lower on the membrane side for each of the 4 periods studied. The tindings suggest that LDF can be a valuable method to study blood perfusion of oral mucosal flaps and that there may be a relationship between a reduced relative LDF value and subsequent exposure of the membrane to the oral environment. 相似文献
7.
6 mandibles were radiographically examined bilaterally to visualise the mandibular canal. 5 imaging techniques were used: periapical radiography, panoramic radiography, hypocycloidal tomography, spiral tomography and computed tomography (CT). Panoramic radiographs were obtained with 2 different X-ray machines. The CT-examinations comprised direct images and standard reconstructions based on axial slices. The specimens were subsequently sectioned for contact radiography. The visibility of the mandibular canal was estimated by 3 observers at special reference points on all radiographs and classified as clearly visible, questionable visibility or not visible. The contact radiographs served as the "gold standard". The inter-observer and the intra-observer agreement were assessed by calculating the overall agreement and the x value. Direct coronal computed tomography, as well as spiral and hypocycloidal tomography, gave better visualisation of the mandibular canal than periapical and panoramic radiography. 相似文献
8.
Changes in atrial natriuretic peptide (ANP), N-terminal proatrial natriuretic peptide and brain natriuretic peptide (BNP) were evaluated in relation to continuously monitored atrial pressures in a pacing model of heart failure. Pigs were subjected to rapid atrial pacing (225 beats min-1) for 3 weeks with adjustments of pacing frequencies if the pigs showed overt signs of cardiac decompensation. Atrial pressures were monitored by a telemetry system with the animals unsedated and freely moving. Left atrial pressure responded stronger and more rapidly to the initiation of pacing and to alterations in the rate of pacing than right atrial pressure. Plasma natriuretic peptide levels were measured by radioimmunoassay and all increased during pacing with BNP exhibiting the largest relative increase (2.9-fold increase relative to sham pigs). Multiple regression analysis with dummy variables was used to evaluate the relative changes in natriuretic peptides and atrial pressures and the strongest correlation was found between BNP and left atrial pressure with R 2=0.81. Termination of pacing resulted in rapid normalization of ANP values in spite of persistent elevations in atrial pressures. This may reflect an increased metabolism or an attenuated secretory response of ANP to atrial stretch with established heart failure. In conclusion, 3 weeks of rapid pacing induced significant increases in atrial pressures and natriuretic peptide levels. All the natriuretic peptides correlated with atrial pressures with BNP appearing as a more sensitive marker of cardiac filling pressures than ANP and N-terminal proatrial natriuretic peptide. 相似文献
9.
10.
Vanhatalo S Parkkisenniemi U Steinbusch HW de Vente J Klinge E 《Journal of chemical neuroanatomy》2000,19(2):169-91
The distribution of immunoreactivity (IR) for the neuropeptide vasoactive intestinal polypeptide (VIP) and neuronal nitric oxide synthase (nNOS) in the bovine retractor penis muscle (RP) and penile artery (PA) was studied by using two different methods. The distribution of these immunoreactivities was also compared with that of the immunoreactivity for cyclic guanosine monophosphate (cGMP). In both tissues the nerve fibers and terminals immunoreactive for VIP had a distribution that was completely different from that of the nerve fibers and terminals immunoreactive for nNOS. This contrasts with the previous observations in penile smooth muscle of other species. In the RP, as well as in the PA, many of the VIP-IR fibers were also immunoreactive for neurofilaments (NF), whereas the nNOS-IR fibers were consistently devoid of NF-IR. Stimulation with sodium nitroprusside, a nitric oxide donor, considerably increased cGMP-IR in the smooth muscle cells in both RP and PA, and in several nerve fibers in PA. Many of these cGMP-IR nerve fibers exhibited nNOS-IR, whereas none of them was immunoreactive for VIP. Our results suggest that the degree of coexistence of VIP-IR and nNOS-IR in the nerve fibers and terminals innervating penile smooth muscle show wide species differences. They also suggest that the mechanisms by which VIP could be involved in neurogenic penile erection may vary between species. 相似文献