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1.
Partial N-terminal amino acid sequences for the three largest nonstructural proteins of two flaviviruses, yellow fever virus and St. Louis encephalitis virus, have been obtained. The determined sequences of these proteins exhibit significant amino acid sequence homology, and allow the positioning of these three nonstructural proteins in the polyprotein sequence deduced from the nucleotide sequence of yellow fever virus (C. M. Rice, E. M. Lenches, S. R. Eddy, S. J. Shin, R. L. Sheets, and J. H. Strauss, 1985, Science 229, 726-733.) The deduced start points support the hypothesis that the N terminus of nonstructural glycoprotein NS1 results from cleavage by signalase, whereas the N termini of NS3 and NS5 result from cleavages following double basic residues that are flanked by amino acids with short side chains.  相似文献   
2.
In obstructive jaundice, free radical production is increased and antioxidative activity is reduced. N-Acetylcysteine (NAC) has a beneficial effect with anti-inflammatory and antioxidant activity, acting as a free radical scavenger. NAC inhibits inducible nitric oxide synthase, suppresses cytokine expression/release, and inhibits adhesion molecule expression and nuclear factor kappa B. The aim of this study was to investigate the effects of NAC on liver/renal tissue and serum lipid peroxidation in lipopolysaccharide (LPS)-induced obstructive jaundice. We randomized 60 rats into 6 groups: group 1, Sham; group 2, obstructive jaundice (OJ) induced after bile-duct ligation; group 3, OJ + NAC (100 mg kg- 1 subcutaneously); group 4, OJ + LPS (10 mg kg-1); group 5, OJ + NAC + LPS; and group 6, OJ + LPS + NAC. For each group, the biochemical markers of lipid peroxidation and the antioxidant products were measured in serum and liver/renal tissue after sacrifice. Almost all lipid peroxidation products levels were increased and antioxidant products levels were decreased in groups who received LPS (groups 4, 5, and 6), but the effect was less remarkable when NAC was administered before LPS (group 5). The same trend was seen for groups with OJ +/- LPS who did not received NAC or received it after induced toxemia (groups 2, 4, and 6) as compared to groups 1 and 3. Moreover, in the case of OJ + LPS, rats treated with NAC before LPS (group 5) had lower lipid peroxidation products levels and higher antioxidant products levels as compared to those who did not received NAC (group 4). This phenomenon was not reproducible with NAC administered after LPS (group 6). Thus, results of this study showed that NAC prevents the deleterious effects of LPS in obstructive jaundice by reducing lipid peroxidation in serum and liver/renal tissue if administered before LPS. Nonetheless, NAC failed to prevent the lipid peroxidation in the case of established endotoxemia in obstructive jaundice.  相似文献   
3.
We investigated the brainstem integrity in children with primary nocturnal enuresis (PNE) using auditory brainstem responses (ABR), blink reflex and exteroceptive suppression of the masseter muscle. We examined 23 children with PNE (16 male, 7 female; mean age: 10.4 years) and 19 control subjects (11 male, 8 female; mean age: 11.8 years). ABR parameters such as wave latencies, amplitudes and interpeak latencies and blink reflex parameters such as R1 and R2 amplitude and latencies were not significantly different between the 2 groups. Although S2 parameters of the exteroceptive suppression of the masseter muscle were easily and completely obtained from the control subjects, in the PNE group S2 onset latency and duration were not recorded in 26% of the study children (n = 6) (P = 0.01). S2 duration time was significantly lowered in the enuretic group (left side: P = 0.001 and right side: P = 0.003). S2 duration time changes in the enuretic group supports a possible brainstem dysfunction in children with PNE.  相似文献   
4.
Although the appendix has been recognized as a preferential site for carcinoid tumors in obese patients, no definitive guidelines are so far available regarding the management of these patients when candidates for bariatric surgery. This study was designed to fill that gap. Between 2000-2008, 558 patients underwent bariatric procedures. Appendectomy was routinely performed in 477 cases. Their charts were retrospectively retrieved and histopathology responses on surgical specimens were recorded. We aimed to assess: incidence of appendix carcinoid tumors (ACTs) and any possible risk-factor; modality of diagnosis (pre-, intra- or post-operatively); impact on the planned bariatric procedure; treatment reserved to such cases. Typical ACTs were diagnosed in 7 patients (1.4%) (median age: 33 years; median BMI: 49 kg/m2; males/females: 1/6). Four were diagnosed intra-operatively. Because of dimensions (<2 cm) and absence of mesoappendiceal or serosal involvement, simple appendectomy was performed during bariatric procedure, as planned. Three were diagnosed post-operatively (all <2 cm). In 1 case right hemicolectomy was performed 1 month later due to mesoappendiceal involvement. No appendectomy-related complication was encountered. All patients remained tumor-free during follow-up (mean: 64 months; range, 25-92). Young age, female sex, high BMI and diabetes mellitus resulted significantly associated with ACT. Our study sustains routine appendectomy or at least careful investigation of the appendix during bariatric surgery. For tumors <2 cm without mesoappendiceal or serosal involvement, simple appendectomy proved sufficient. Bariatric surgery did not have a negative effect on the treatment of malignancies that are discovered intra- or post-operatively.  相似文献   
5.
ObjectiveTo examine CD99 expression and its functional role in ICAM-1 induction in human gingival fibroblasts (HGFs) and human gingival epithelial cells (HGECs) by activating cells with anti-CD99 monoclonal antibody, MT99/3.BackgroundEngagement of CD99 with agonistic antibodies has been shown to regulate immune responses, cell adhesion and migration, and cell death in several studies. Particularly, this engagement results in transendothelial migration of leukocytes mediated by intercellular adhesion molecule-1 (ICAM-1) induction in endothelial cells.MethodsTotal mRNA and protein were isolated from HGFs and HGECs for analyses of CD99 and ICAM-1 expression. Surface expression of CD99 and ICAM-1 was analysed by flow cytometry, and the detection of soluble ICAM-1 was assayed by immunoprecipitation and ELISA.ResultsCD99 surface expression was constitutive on HGFs to a greater extent than that on HGECs. CD99 ligation with MT99/3 induced ICAM-1 mRNA expression in HGFs, but not in HGECs. Interestingly, CD99 ligation led to an increased level of soluble ICAM-1 detected in culture supernatant, whereas interleukin-1β (IL-1β) treatment induced expression of membrane-bound ICAM-1. Furthermore, ICAM-1 induction by CD99 engagement was demonstrated to involve the activation of the p50 subunit of nuclear factor-kappaB (NF-κB), extracellular signal-regulated kinase, and p46 c-Jun N-terminal kinase that differed from that by IL-1β treatment.ConclusionOur study has shown the involvement of CD99 ligation in the up-regulation of ICAM-1 expression and its secretion in gingival fibroblasts, which may be essential for better understanding of the pathogenesis of periodontal disease.  相似文献   
6.
7.
Treatment of viable cesarean scar ectopic pregnancy with suction curettage.   总被引:5,自引:0,他引:5  
OBJECTIVE: Pregnancy in previous cesarean scar is the rarest form of ectopic pregnancy. All reported cases in the literature that were treated with uterine curettage either become unsuccessful or complicated. We aimed to present a case of cesarean scar ectopic pregnancy that was successfully treated with suction curettage without any additional therapy. CASE: A 32-year-old asymptomatic woman, gravida 2, para 1 was referred to our hospital with the possible diagnosis of cervical ectopic pregnancy. Transvaginal and transabdominal sonographic examination revealed the diagnosis of viable ectopic pregnancy in a previous cesarean scar. Suction curettage with carman canulles was performed under transabdominal ultrasonographic guidance. beta-hCG decreased progressively postoperatively. CONCLUSION: Suction curettage under ultrasonography guidance can be used in termination of selected cases (early diagnosed, without symptoms that necessitates emergency intervention) of cesarean scar pregnancy.  相似文献   
8.
BACKGROUND AND AIMS: Postprandial increase of 5-hydroxytryptamine (5-HT) has been implicated in irritable bowel syndrome (IBS). There is evidence that nitric oxide (NO) may act as a mediator of 5-HT-evoked secretions in the colon. Our aim is to investigate the role of urinary 5-hydroxyindole acetic acid (5-HIAA) and plasma NO levels (with diarrhoea) in IBS patients. Methods: Nineteen (with constipation) IBS patients (group 1), 22 IBS patients (group 2) and 18 healthy controls (group 3) were included in the study. The diagnosis of IBS was made according to the Rome I Criteria. The urine was collected for determination of 5-HIAA and venous blood was collected from each subject for the measurement of plasma NO levels. RESULTS: The levels of urinary 5-HIAA mmol/day and plasma NO mmol/l of group 1 (22.4 +/- 2.2 and 29.4 +/- 2 respectively) were significantly higher than group 3 (14.2 +/- 2.3 and 21.3 +/- 2.1 respectively) (p = 0.036 and p = 0.019 respectively). The NO level of group 1 was also significantly higher than group 2 (21.8 +/- 1.9) (p = 0.021). The 5-HIAA level of group 1 was higher than group 2 (15.2 +/- 2.1) and the difference was marginally significant (p = 0.055). There was no difference between group 2 and group 3 with respect to 5-HIAA and NO levels. CONCLUSIONS: The results of this preliminary study lend support to the involvement of 5-HT in some symptomatology of diarrhoea predominant IBS. Furthermore, NO may be one of the effector mediators of the 5-HT-induced symptoms in these patients.  相似文献   
9.
Cervical cystic masses may be a diagnostic challenge, especially in patients older than 40 years. We present the case of a 62-year-old male patient with a large cystic metastasis of squamous cell carcinoma to the neck and discuss this rare condition regarding diagnostic, pathologic and therapeutic features.  相似文献   
10.
The high co-occurrence of an abdominal wall hernia (AWH) and stress urinary incontinence (SUI) suggests that there is a common factor in the etiopathogenesis of these disorders in these patients.  相似文献   
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