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991.
Management of infected aortic aneurysms, which can be life-threatening, remains challenging. Open surgical treatments, including debridement of the infected aorta and the surrounding tissue and either in situ reconstruction or extra-anatomic bypass covering with omentum or muscle flap, are the mainstay of therapy. However, increasing advances in technology have made endovascular treatment of infected aneurysms feasible. The present study describes the first clinical report of successful treatment of an infected aneurysm using endovascular techniques in the acute phase, followed by delayed open surgery.  相似文献   
992.
We hereby present our technique for using the self-retaining flexible arm retractor and its attachments for mitral valve exposure. The Aortic Valve Assistant, which was developed for aortic valve exposure, is also very useful for exposure of the inferior wall of the left atrium. Our modified atrial hook provides excellent exposure of the anterior mitral annulus. Extensive dissection and the combined use of the flexible arm and attachments allows us comfortable access for mitral valve operations.  相似文献   
993.
Objectives: Ischemic mitral regurgitation results from annular dilatation, leaflet tethering and leaflet flattening. Undersized annuloplasty corrects annular dilatation but worsens leaflet tethering and flattening. This exacerbation of abnormal leaflet geometry may contribute to poor repair results for ischemic mitral regurgitation (IMR). Using a sheep model of IMR, we hypothesized that posterior leaflet augmentation and less-extreme annular undersizing would relieve tethering and increase leaflet curvature. Methods: Eight weeks after posterolateral infarct, 10 sheep with ≥2+ IMR underwent either a 24-mm planar ring annuloplasty (n = 5) or a 30-mm planar ring annuloplasty with concomitant posterior leaflet augmentation (n = 5). Real-time three-dimensional echocardiography allowed measurement of indices of leaflet curvature and tethering before and after annuloplasty. Results: Comparing pre- and post-repair values in the P1, P2, and P3 leaflet regions, undersized 24-mm ring annuloplasty made no significant difference to mean septolateral curvature (0.23–0.26, 0.33–0.29, and 0.27–0.37 cm−1, respectively), whereas leaflet augmentation in combination with a 30-mm ring annuloplasty increased septolateral curvature (P1 0.30–1.02, P2 0.31–1.23, and P3 0.35–0.84 cm−1, p-values < 0.05). The mean tethering angle formed between the annular plane and the posterior leaflet increased in all three posterior regions for the 24-mm ring group (P1 12–23°, P2 26–31°, and P3 16–25°), but decreased in all regions for the group undergoing leaflet augmentation (P1 +5 to −6°, P2 +13 to −13°, P3 +16-15°, all p-values < 0.05). Conclusions: Undersized annuloplasty exacerbates leaflet tethering. Posterior leaflet augmentation with less severe annular reduction increases leaflet curvature and decreases tethering; this technique more completely addresses the pathogenic mechanism of IMR and may improve repair durability.  相似文献   
994.
The sentinel node (SN) is regarded as the first drainage lymph node, and tumor cells are considered likely to directly affect the SN. However, few reports have identified differences between SNs and non-SNs in cancer patients. Subjects in this study included 27 patients with gastric cancer who underwent curative operation and intraoperative detection of SNs by radioisotope methods. The mean number of SNs was 3.2 (range 1 to 5). Degree of infiltration of natural killer cells, dendritic cells, MIB-1 labeling index, and CD3-ξ expression of lymphocytes in SNs and non-SNs were examined by means of immunohistochemical methods. Degree of infiltration was compared according to depth of invasion and between SNs and non-SNs. Patients with early-stage cancer displayed a greater degree of infiltration of MIB-1 labeling index and CD3-ξ expression than patients with pT2 or pT3 lesions (P<0.05). The MIB-1 labeling index in SNs was significantly lower than that in non-SNs (P<0.05). However, no significant difference was observed in infiltration of natural killer cells, dendritic cells, or CD3-ξ. Morphologic changes of dendritic cells in SNs were not definite. Our results suggest that SNs in gastric cancer might not be suppressed, unlike in breast cancer and melanoma. SN paralysis may depend on tumor- and organ-specific characteristics or exogenous stimulation from the gastric mucosa. Studies in progress will help to identify immunologic paralysis of the SN in various types of cancer. Attention must therefore be paid to organ specificity.  相似文献   
995.
Neoadjuvant chemotherapy has become standard treatment for breast cancer patients to avoid mastectomy in larger tumors. Neoadjuvant chemotherapy permits more breast-conserving surgery to be performed. The treatment outcome is favorable in women whose tumors show a complete pathological response. Histological grade, HER-2, p53, and hormone receptor status are significant predictive factors of a good pathological response to neoadjuvant chemotherapy. In addition, computed tomography and/or magnetic resonance imaging are useful tools in determining the optimal resection area for breast cancer.  相似文献   
996.
BACKGROUND/AIMS: C-reactive protein (CRP) was recently identified as a prognostic factor for patients with hepatocellular carcinoma (HCC) after surgical resection. We investigated the relationship between the serum levels of high sensitivity CRP (H-CRP) and the prognosis of HCC patients. METHOD: We conducted a cohort study of 90 HCC patients enrolled from 1997 to 1998. All patients were treated and followed for a mean period of 3.2 years. Clinical variables were compared between patients positive for H-CRP (serum H-CRP levels >/=3.0 mg/L, n=47) and those negative for H-CRP (serum H-CRP levels <3.0 mg/L, n=43). We also determined the relationship between serum H-CRP and prognosis in HCC patients. RESULTS: The survival rate of patients of the H-CRP-positive group was lower than that of H-CRP-negative patients. Tumour stage (stages 3 or 4), total bilirubin >/=1.2 mg/dL, albumin (Alb) <3.5 g/dL, des-gamma-carboxy prothrombin >/=40 mAU/mL, positive H-CRP and initial treatment (transcatheter arterial chemoembolization, hepatic arterial infusion chemotherapy or best supportive care) were identified as significant poor prognostic factors by univariate analysis, while positive H-CRP [hazard ratio (HR), 1.58; P=0.048], Alb<3.5 g/dL (HR, 2.10; P=0.004), tumour stage (stages 3 or 4; HR, 3.05; P=0.001) and initial treatment (HR, 1.88; P=0.029) were considered to be significant determinants of poor prognosis by multivariate Cox proportional hazards analysis. CONCLUSIONS: The prognosis of H-CRP-positive patients was poorer compared with H-CRP-negative patients. This study confirmed that H-CRP, like CRP, is a marker of poor prognosis in HCC patients.  相似文献   
997.
998.
We examined the mechanism of action of lysophosphatidylcholine (lyso-PC), which is suggested to be involved in the pathogenesis of atherosclerosis and inflamatory disorders, and its interaction with well-known vasoactive compounds such as hydrogen peroxide (H2O2), thromboxane A2 (TX-A2), serotonin (5-HT), angiotensin II (Ang-II), endothelin-1 (ET-1), or urotensin II (U-II) on VSMC proliferation. Growth-arrested rabbit VSMCs were incubated with given concentrations of lyso-PC with H202, TX-A2, 5-HT, Ang-II, ET-1, or U-II. [3H]Thymidine incorporation into DNA was measured as an index of VSMC proliferation. Lyso-PC induced a maximal effect on [3H]thymidine incorporation at a concentration of 15 microM (156%), and its effect was significantly inhibited by the phospholipase C inhibitor U73122 (10 microM), the intracellular antioxidant NAC (400 microM), and the NADPH oxidase inhibitor diphenylene iodonium (1 microM), but not by the MAPK kinase inhibitor (10 microM). H2O2, TX-A2, 5-HT, Ang-II, ET-1, or U-II also stimulated [3H]thymidine incorporation in a dose-dependent manner. A non-mitogenic concentration of lyso-PC (5 microM) significantly potentiated the effect of low concentrations of H2O2 (0.1 microM, 110 to 222%), TX-A2 (5 microM, 120 to 202%), 5-HT (5 microM, 182 to 259%), Ang-II (0.5 microM, 167 to 304%), ET-1 (0.01 microM, 139 to 297%), or U-II (0.025 microM, 120 to 332%) on [3H]thymidine incorporation. The results suggest that lyso-PC acts synergistically with the vasoactive compounds H2O2, TX-A2, 5-HT, Ang-II, ET-1, or U-II in inducing VSMC proliferation, which may play an important role in the progression of atherosclerosis.  相似文献   
999.
Unlike conventional T cells, which are exported from the thymus as naive cells and acquire effector functions upon antigen encounter in the periphery, a subset of γδ T cells differentiates into effectors that produce IL-17 within the fetal thymus. We demonstrate here that intrathymic development of the naturally occurring IL-17-producing γδ T cells is independent of STAT3 and partly dependent on RORγt. Comparative gene-expression analysis identified Hes1, one of the basic helix-loop-helix proteins involved in Notch signaling, as a factor specifically expressed in IL-17-producing γδ T cells. Hes1 is critically involved in the development of IL-17-producing γδ T cells, as evidenced by their severe decrease in the thymi of Hes1-deficient fetal mice. Delta-like 4 (Dll4)-expressing stromal cells support the development of IL-17-producing γδ T cells in vitro. In addition, conditional Hes1 ablation in peripheral γδ T cells decreases their IL-17 production but not their IFN-γ production. These results reveal a unique differentiation pathway of IL-17-producing γδ T cells.  相似文献   
1000.
Long sickness absence is more common among low socioeconomic status (SES) groups than high SES groups. This study aimed to evaluate whether work and family characteristics contribute to SES and sex differences in long sickness absence (7 days or more). The participants were 3080 civil servants working for a local Japanese government. In both sexes, low-grade employees were likely to take long sickness absence, with a statistically significant association for men (age-adjusted OR of lowest-grade employees for long sickness absence: 2.30 (95% Confidence Interval (CI): 1.32–4.02)). After adjusting for all variables, SES differences in long sickness absence in men decreased to OR 1.98 (CI 1.10–3.55) but remained significant; in men, being without a spouse was significantly associated with long sickness absence. Employees working long hours had lower OR for long sickness absence after adjusting for all variables in both sexes. Conversely, poor sleep quality and longstanding illness significantly increased OR for long sickness absence. In conclusion, SES differences in sickness absence were explained partly by work and family characteristics, longstanding illness, and poor sleep quality; however, other factors that were not evaluated in this study may also be associated with SES differences.  相似文献   
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