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1.
Background: Stones of the common bile duct are the most important factor in acute pancreatitis (AP). Endolaparoscopic surgery plays a well-recognized role in the treatment of this pathology. Methods: From January 1992 to December 1995 we observed 62 cases of acute biliary pancreatitis (ABP). In 57 cases (= 93.4%) we proposed a minimally invasive treatment, based on performance of endoscopic retrograde cholangiopancreatography (ERCP) combined with endoscopic sphincterotomy (ES) and then of laparoscopic cholecystectomy (LC). Results: ERCP was attempted in emergency in 40/57 cases and successfully done in 34 cases. An ES was performed in all but two cases. In 51 patients we performed LC. The overall morbidity was 8.9% with no mortality. Conclusions: In the case of ABP early treatment can achieve the restoration of patency of the papilla, reducing the risk of associated cholangitis and the development of pancreatic necrosis. The cholecystectomy prevents the risk of relapse of ABP.  相似文献   
2.
We have evaluated whether cyclosporine A affects cell structure and cytoskeletal proteins of the thymus of Wistar rats. Immunohistochemical analysis showed that expression of the cytoskeletal proteins vimentin and desmin was much higher in epithelial cells, dendritic cells and lymphocytes in the thymus of treated rats than in untreated controls. Protein expression was observed as a positive condensation in a distinct area near the nucleus with a capping-like configuration. An ultrastructural study showed that the amount of cytoskeletal fibrillar structures was increased in the treated rats. The structures were assembled in a limited area of the cell with a nuclear capping-like configuration which was in agreement with the light microscopical observations. Immunoblotting analysis demonstrated that vimentin and desmin had a lower molecular weight in treated rats than in controls (57 and 53 kDa versus 55 and 51 kDa, respectively). The results clearly indicate that cyclosporine A affects the structure of the cytoskeleton suggesting that this could be the first step in its immunosuppressive effects by altering nucleus/cytoplasm signaling.  相似文献   
3.
We have evaluated the clinical significance of hepatitis C virus (HCV) RNA determination by analyzing a group of 221 hospitalized patients with abnormal liver function tests. Serum HCV RNA was detected by "nested" PCR amplification followed by nonisotopic hybridization. Of the 200 (90.5%) patients with anti-HCV-positive enzyme-linked immunosorbent assay results, 152 (76%) were RIBA reactive, 47 (23.5%) had indeterminate results, and 1 (0.5%) was nonreactive. Of the 180 (90%) patients positive for anti-HCV and HCV RNA, 138 (76.7%) were RIBA reactive and 42 (23.3%) were RIBA indeterminate. The pattern of RIBA reactivity did not correlate with the presence of HCV RNA. Elevated alanine aminotransferase levels were associated neither with the presence of viremia nor with the RIBA pattern. Histological findings consistent with non-A non-B hepatitis correlated with the presence of HCV RNA but not with the RIBA pattern. HCV RNA was detected in 11 of 21 (52.4%) anti-HCV-negative patients. These 11 patients were either immunosuppressed or in the prodromic phase of acute hepatitis C. Circulating HCV RNA can therefore be described as being predictive of virus-induced liver damage in anti-HCV-positive patients and may be useful in the diagnosis of HCV infection in anti-HCV-negative immunosuppressed patients or in those with early acute infection.  相似文献   
4.
Neurosurgical Review - Transorbital endoscopic approaches are increasing in popularity as they provide corridors to reach various areas of the ventral skull base through the orbit. They can be used...  相似文献   
5.
The Mallory-Weiss (M-W) syndrome is responsible for about 7.5% of all bleedings of oesophageal origin. Emergency endoscopic treatment allows to obtain a rapid diagnosis as well as an effective treatment. Personal experience on 160 cases of M-W tears (14.2% of all oesophageal bleeding) is reported. The tears were classified in three groups: IA and IB (30 cases); IIA and IIB (48 cases); IIC and III (82 cases). In the first two groups a complete haemostasis was obtained in 73 out of 78 cases (93.6%) with a single session and in 5/78 cases with two sessions of sclerotherapy. The third group was treated with medical therapy. There was no procedure related mortality. An analysis of etiologic factors, anatomic conditions and pathogenetic correlations has highlighted the role of portal hypertension in cirrhotic patients in favouring the bleeding in some of these patients and the role of hiatal hernia and cardial incontinence in determining the site of the lesions.  相似文献   
6.
Summary The relationship between tumor proliferative activity and response to first-line chemotherapy and survival was investigated in 76 advanced breast cancer patients. Proliferative activity was determined by means of Ki-67 immunohistologic staining on primary tumors (55 patients) or at the relapse site (21 patients), and was classified as low ( 25% of stained cells) or high (> 25% of stained cells). The usual WHO response criteria were used. The median duration of follow-up was 18 months (range 3–58).Forty-seven patients (62%) had tumors with low, and 29 (38%) had tumors with a high rate of proliferative activity. The two groups were well balanced in terms of important variables such as disease-free survival, performance status, age, menopausal status, and the type of first-line chemotherapy (anthracycline-based regimens versus cyclophosphamide-methotrexate-5-fluorouracil). The estrogen receptor (ER) content, measured by means of immunohistochemical assay, was markedly different in the two groups, with 27/47 tumors with low proliferative activity (57%) and 6/29 with high-proliferative activity (21%) being ER positive ( 45% of stained cells) (p = 0.003). Moreover, a significant difference in the metastatic pattern was also evident, with a higher incidence of bone and a lower incidence of soft tissue metastases in the group of patients with tumors with low proliferative activity (p = 0.004). Overall, 10/47 responses (21%: PR = 7, and CR = 3) were observed in the group with a low rate of proliferative activity, versus 14/29 (48%: PR = 9, and CR = 5) in the group with highly proliferative tumors, the difference being statistically significant (p = 0.03). When a multivariate analy-sis was performed, the only factor that retained independent prognostic significance was the predominant site of disease, particularly soft tissues (p = 0.003). Despite the difference in response rate, when survival analysis was performed according to the Kaplan-Meier method, no significant difference was observed in the two groups, but when the analysis was limited to responsive patients, the median survival observed in those with a low and those with a high rate of proliferation was 35 and 19 months respectively (p = 0.02). The same results were obtained when multivariate survival analysis was carried out using Cox's regression model. These data suggest that there is a link between tumor proliferative activity and response to chemotherapy in advanced breast cancer, and may indicate the need to use more intensive treatments in selected patients with highly proliferative tumors.Presented in part at the Annual Meeting of the American Society of Clinical Oncology, May 14–17, 1994, Dallas, TX, USA  相似文献   
7.
8.
We investigated the effects of human immunodeficiency type-1 virus (HIV-1) matrix protein p17 on freshly isolated and purified human natural killer (NK) cells. HIV-1 p17 increased the cytokines interleukin (IL) 2, IL-12 and IL-15, and induced natural killer cell proliferation, but not cytotoxicity. This effect was specific because it was abrogated by anti-p17 monoclonal antibody. Moreover, HIV-1 p17 enhanced the cytokine-induced production of tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma by NK cells. IL-4 downregulated IFN-gamma and TNF-alpha secretion in IL-2- and IL-15-treated NK cells. HIV-1 p17 restored the ability of NK cells to produce both cytokines when added to the cultures simultaneously with IL-4. The property of p17 to increase the production of TNF-alpha and IFN-gamma might be a mechanism used by HIV-1 to modulate the immune system to support its replication and spreading.  相似文献   
9.
Mercuric chloride (HgCl 2 ) produces an acute renal failure in experimental animal models. Since the mechanism of tubular injury has not completely been clarified, this morpho-quantitative study was undertaken to better understand the effects of 2 sublethal doses (T1=1 mg/kg and T3.5=3.5 mg/kg) of HgCl 2 in rat proximal tubules. Morphometrical analysis was performed to quantify both cytoplasmic and nuclear changes found in treated in respect to saline-injected proximal tubules. In the controls, single-cell damage was occasional and nucleolar changes were absent. HgCl 2 induced progressively severe proximal tubule atrophy. In the T1 group, necrosis was limited to pars recta cells and nucleolar segregation was often partial. In the T3.5 group, atrophy was extensive in both convoluted and straight tracts, the nucleolus was completely segregated and coiled body-like inclusions were detached from it. Ultrastructural analysis confirmed dose-dependent changes within straight proximal tubules, i.e., necrosis, apoptosis, nucleolar segregation, swollen mitochondria, vacuolization, and disrupted brush border. In conclusion, in the rat kidney HgCl 2 induced dose-dependent alterations not only in the cytoplasm but also in the nucleus of proximal tubule cells. These findings will be useful for better understanding of the pathogenesis of mercury nephrotoxicity and its genotoxic effect.  相似文献   
10.
Atherosclerosis is a chronic vascular disease in which oxidative stress and inflammation are commonly implicated as major causative factors. Identification of novel strategies that contribute to plaque stabilization or inhibition represents a continuing challenge for the medical community.  相似文献   
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