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81.
The effects of Kupffer cells on cytokine responses in endotoxin-enhanced reperfusion injury after total hepatic ischemia were investigated in this study. Male rats pretreated with either normal saline solution (NS group) or gadolinium chloride (GdCl(3)) to inhibit Kupffer cell function (GC group) were subjected to 60 min of hepatic ischemia. These animals received either normal saline solution or sublethal doses of endotoxin (1 mg/kg) at reperfusion. In the NS group, endotoxin administration induced an enhanced tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 production 1 h after reperfusion with a subsequent peak of macrophage inflammatory protein-2 (MIP-2) levels, which resulted in a 7-day survival rate of 30%. Despite endotoxin administration, GdCl(3) pretreatment significantly suppressed TNF-alpha and increased interleukin-10 production 1 h after reperfusion, which led to a decline in MIP-2 production and amelioration of functional and structural liver damage with a 7-day survival rate of 80%. Augmented pro-inflammatory and anti-inflammatory cytokine responses by Kupffer cells were associated with endotoxin-enhanced reperfusion injury after hepatic ischemia. Kupffer cell blockade has a potential to attenuate the insult via modulation of cytokine responses.  相似文献   
82.
In scaphoid fractures, delayed diagnosis and nonunion are fairly common as a result of several factors, including the difficulty of radiographic diagnosis of non-displaced fractures and underestimation of the injury by the patient. Main factors to consider when deciding treatment are the type of fracture and fracture stability. In the stable nonunion (Type D1 according to the Filan and Herbert classification, or linear type of Ikeda’s classification), percutaneous screw fixation without bone graft is recommended. The indications of non-vascularized bone grafting are as follows: (1) arthroscopic cancellous bone graft in type D1 and cystic type of Ikeda’s classification. (2) tricortical bone graft from the iliac crest in type D2 or D3 if the possibility of avascular necrosis of the proximal fragment is excluded. In this paper, our non-vascularized bone grafting for scaphoid nonunion would like to be described mainly about principles and type of fixation.  相似文献   
83.
A rare abnormality of the A1 segment of the anterior cerebral artery (ACA) is reported. The right ACA bifurcated into two parts at the middle point of the A1 segment, and these segments did not rejoin. The superior right A1 segment connected with the left A1 and formed a single pericallosal artery. The inferior right A1, from which the right ophthalmic artery originated, had no connection with the left A1.  相似文献   
84.
Allogeneic cultured dermal substitute (CDS) was prepared by culturing fibroblasts on a two-layered spongy matrix of hyaluronic acid (HA) and atelo-collagen (Col). CDS can be cryopreserved and transported to other hospitals in a frozen state. The present study was designed to analyze amounts of cytokines released from fibroblasts in fresh or cryopreserved CDS. The culture medium used in preparing CDS over a cultivation period of 1 week (fresh CDS culture medium sample) contained vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), hepatocyte growth factor (HGF), platelet derived growth factor (PDGF)-AA, transforming growth factor (TGF)-beta1, keratinocyte growth factor (KGF), interleukin (IL)-6 and IL-8. After thawing of cryopreserved CDS, the CDS was re-cultured in medium for 1 week. The culture medium used in re-culturing CDS for 1 week (cryopreserved CDS culture medium sample) contained VEGF, bFGF, and HGF in the same concentration as before freezing, and TGF-beta1 and IL-8 at half the concentration before freezing. Levels of PDGF-AA, KGF, and IL-6 were significantly less than before freezing. This finding suggests that the cryopreserved CDS retains its ability to release VEGF, bFGF, and HGF that are essential for wound healing.  相似文献   
85.
Background and Objectives  Dickkopf-1 (DKK1) is the inhibitor of the canonical Wnt signaling pathway, however it is highly transactivated in various cancers, suggesting the presence of unknown mechanism. Its implication in human esophageal squamous cell carcinoma (ESCC) has not been sufficiently investigated. Patients and Methods  We evaluated DKK1 protein expression in resected specimens from 170 patients with ESCC by immunohistochemistry. Tumors were categorized as positive or negative for DKK1. The relationships between DKK1 expression in ESCC and various clinicopathological parameters and prognosis (disease-free survival; DFS) were analyzed separately. Results  Immunohistochemically, 72 (42.4%) tumors were DKK1 positive while no significant staining was observed in the normal squamous epithelium except for few basal cells. There was no significant relationship between DKK1 expression in ESCC and any of the clinicopathological parameters tested in this study. Patients with DKK1-positive tumors had poorer DFS than those with negative ESCC (5-year DFS; 31.5% versus 53.6%, P = 0.0062). Univariate analysis showed a significant relationship between pT [hazard ratio (HR) = 2.944, 95% confidence interval (CI) = 1.713–5.059, P < 0.0001], number of pN (HR = 2.836, 95% CI = 1.866–4.309, P < 0.0001), lymphatic invasion (HR = 2.892, 95% CI = 1.336–6.262, P = 0.0070), and DKK1 expression (HR = 1.763, 95% CI = 1.167–2.663, P = 0.0071) and DFS. Multivariate analysis including the above four parameters identified pT (HR = 2.053, 95% CI = 1.157–3.645, P = 0.0140), pN number (HR = 2.107, 95% CI = 1.362–3.260, P = 0.0008), and DKK1 expression (HR = 1.813, 95% CI = 1.195–2.751, P = 0.0052) as independent and significant prognostic factors for DFS. Conclusion  Our data suggest the usefulness of DKK1 as a novel predictor of poor prognosis of patients with ESCC after curative resection and also as a therapeutic target for future tailored therapies against ESCC.  相似文献   
86.
87.
Objective: Surgical treatment of thoracic aortic surgery in patients with coronary artery disease was investigated. Methods: Between 1990 and April 2003, 330 patients underwent elective thoracic aortic surgery. Fifty-six patients who underwent aortic root reconstruction were excluded and 274 patients were examined. Fifty-four (20%) patients showed concomitant coronary artery disease. Ten had undergone coronary revascularization previously; and 3 underwent coronary revascularization [2 coronary artery bypass grafting (CABG), 1 percutaneous transluminal coronary angioplasty (PTCA)] before aortic surgery. Twenty-three patients underwent elective CABG simultaneously and 2 patients had additional coronary artery bypass because of cardiac ischemia during operation. The number of patients who underwent thoracic aortic surgery including Asc Ao+AVR was 2, hemi arch 1, total arch 15, distal arch 5, distal arch+LV aneurysmectomy 1, and thoracoabdominal Ao 1. Two patients underwent coronary revascularization with arterial grafts and the others with SVG grafts. Results: There was one hospital death (4%). In patients without coronary bypass, 2 patients suffered cardiac ischemic events. Conclusion: Our thoracic aortic operations with concomitant CABG using SVG were overall successful. Our current strategies for thoracic aortic surgery in patients with concomitant coronary artery disease include conducting a dipyridamole myocardial perfusion-imaging test first in patients not at risk of coronary artery disease, and if the test is positive, coronary angiography is performed and aggressive coronary revascularization is conducted where possible.  相似文献   
88.
Background The purpose of this study was to investigate the natural course of the minimally symptomatic nonoperated hip in patients with preosteoarthritis or early osteoarthritis in bilaterally dysplastic hips. Methods The material consisted of 61 patients with bilaterally dysplastic hips who underwent rotational acetabular osteotomy in their symptomatic hip and nonoperative treatment in their asymptomatic or minimally symptomatic hip. The average follow-up was 10.1 years (range 7.0–15.6 years), and the average age at the time of surgery was 38.2 years (range 20–58 years). All patients were divided into two groups by joint congruity of the nonoperated hip at surgery with rotational acetabular osteotomy. Results On radiographic assessment, 1 of the 35 preosteoarthritis hips had developed early osteoarthritis, and 6 of the 26 early osteoarthritis hips had progressed to advanced osteoarthritis. The Kaplan-Meier survivorship analysis for the whole group of nonoperated hips, with radiographic progression of osteoarthritis as the endpoint, predicted a 10-year survival rate of 83.7% (95% confidence interval 70%–98%). Significant differences were observed in the radiographic stage (pre- and early osteoarthritis group, P = 0.015) and joint congruity (good and fair group, P = 0.005). Conclusions If the contralateral nonoperated hip has good joint congruity, minimal symptoms, and no or little radiographic change in patients with pre- or early osteoarthritis and bilateral acetabular dysplasia, the probability of radiographic progression is low.  相似文献   
89.
BACKGROUND: Tranexamic acid, an inhibitor of fibrinolysis that blocks the lysine-binding site of plasminogen to fibrin, has been reported to reduce intraoperative and postoperative blood loss in patients undergoing total hip arthroplasty with cement. However, there have been few reports describing the effects of tranexamic acid on blood loss during and following total hip arthroplasty without cement. METHODS: We investigated the effects of tranexamic acid in twenty-one patients who underwent staged bilateral total hip arthroplasty without cement for the treatment of osteoarthritis of the hip. The average interval between the two procedures was 16 +/- 16 months. On one side, 1000 mg of tranexamic acid was administered intravenously five minutes before the skin incision. On the other side, tranexamic acid was not administered. Baseline hemoglobin and hematocrit values were obtained three weeks before each arthroplasty. The volume of postoperative blood loss was recorded at two-hour intervals for the first twelve hours and then again at twenty-four hours, and the values were compared between the two groups. RESULTS: The total intraoperative blood loss in the tranexamic acid group (607 +/- 298 mL) was similar to that in the control group (633 +/- 220 mL). The postoperative blood loss in the tranexamic acid group was significantly lower than that in the control group at all time-points during the first twenty-four hours (p < 0.001 for all comparisons). The greatest reduction in blood loss was observed during the first four hours after surgery in the tranexamic acid group (p < 0.01). CONCLUSIONS: In patients undergoing total hip arthroplasty without cement, preoperative administration of tranexamic acid is associated with decreased postoperative blood loss during the first twenty-four hours, especially during the first four hours after surgery.  相似文献   
90.
A prospective randomized study was conducted to evaluate the efficacy of prophylactic intravesical instillation of pirarubicin (THP) prior to transurethral resection (TUR) of superficial bladder cancer. A total of 63 patients were randomized into two groups, the THP group and the control group. In the THP group, 30 mg of THP dissolved in 50 ml saline was administered 4 times intravesically for 4 consecutive days before TUR. In the control group, no instillation was performed before TUR. The patients were followed by cystoscopy and urinary cytology every 3 months. The non-recurrence rates in the THP group and control group were 54.1% versus 37.6% at 1 year and 40.4% versus 26.8% at 2 years, respectively (P = 0.086). Time to recurrence for tumors larger than 1 cm was significantly longer in the THP group (P = 0.0137). Time to recurrence for single and grade 1+2 tumors tended to be longer in the THP group (P = 0.09, P = 0.079). No significant adverse effects were observed in any patient. Our findings suggest that intravesical THP instillation prior to TUR would be effective for patients with single, low grade lesions larger than 1 cm of superficial bladder cancer.  相似文献   
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