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41.
42.
We present a novel transurethral technique for cystotomy repair. This method can be used for immediate bladder repair following limited bladder injury and avoids the morbidity associated with laparotomy.  相似文献   
43.
Fas ligand (FasL) is produced by activated T cells and natural killer cells and it induces apoptosis (programmed cell death) in target cells through the death receptor Fas/Apol/CD95. One important role of FasL and Fas is to mediate immune-cytotoxic killing of cells that are potentially harmful to the organism, such as virus-infected or tumour cells. Here we report the discovery of a soluble decoy receptor, termed decoy receptor 3 (DcR3), that binds to FasL and inhibits FasL-induced apoptosis. The DcR3 gene was amplified in about half of 35 primary lung and colon tumours studied, and DcR3 messenger RNA was expressed in malignant tissue. Thus, certain tumours may escape FasL-dependent immune-cytotoxic attack by expressing a decoy receptor that blocks FasL.  相似文献   
44.
We present the spatial structure of binase, a small extracellular ribonuclease, derived from 1H-NMR* data in aqueous solution. The total of 20 structures were obtained via torsion angle dynamics using DYANA program with experimental NOE and hydrogen bond distance constraints and phi and chi1 dihedral angle constraints. The final structures were energy minimised with ECEPP/2 potential in FANTOM program. Binase consists of three alpha-helices in N-terminal part (residues 6-16, 26-32 and 41-44), five-stranded antiparallel beta-sheet in C-terminal part (residues 51-55, 70-75, 86-90, 94-99 and 104-108) and two-stranded parallel beta-sheet (residues 22-24 and 49-51). Three loops (residues 36-39, 56-67 and 76-83), which play significant role in biological functioning of binase, are flexible in solution. The differences between binase and barnase spatial structures in solution explain the differences in thermostability of binase, barnase and their hybrids.  相似文献   
45.
Proadrenomedullin N-terminal 20 peptide (PAMP-[1-20]; ARLDVASEFRKKWNKWALSR-amide) is a potent hypotensive and catecholamine release-inhibitory peptide released from chromaffin cells. We studied the mechanism of PAMP action and how its function is linked to structure. We tested human PAMP-[1-20] on catecholamine secretion in PC12 pheochromocytoma cells and found it to be a potent, dose-dependent (IC50 approximately 350 nmol/L) secretory inhibitor. Inhibition was specific for nicotinic cholinergic stimulation since PAMP-[1-20] failed to inhibit release by agents that bypass the nicotinic receptor. Nicotinic cationic (22Na+,45Ca2+) signal transduction was disrupted by this peptide, and potencies for inhibition of 22Na+ uptake and catecholamine secretion were comparable. Even high-dose nicotine failed to overcome the inhibition, suggesting noncompetitive nicotinic antagonism. N- and C-terminal PAMP truncation peptides indicated a role for the C-terminal amide and refined the minimal active region to the C-terminal 8 amino acids (WNKWALSR-amide), a region likely to be alpha-helical. PAMP also blocked (EC50 approximately 270 nmol/L) nicotinic cholinergic agonist desensitization of catecholamine release, as well as desensitization of nicotinic signal transduction (22Na+ uptake). Thus, PAMP may exert both inhibitory and facilitatory effects on nicotinic signaling, depending on the prior state of nicotinic stimulation. PAMP may therefore contribute to a novel, autocrine, homeostatic (negative-feedback) mechanism controlling catecholamine release.  相似文献   
46.
OBJECTIVE: To examine the association of peripheral blood mononuclear cell (PBMC) derived interleukin 1beta (IL-1beta), IL-1 receptor antagonist (IL-1Ra), tumor necrosis factor alpha (TNF-alpha), and radiographic osteoarthritis (OA) in the elderly. METHODS: A total of 703 subjects (436 women, 267 men, mean age 78.5+/-4.5 yrs) had both knee and hand radiographs, and cytokines were measured during the 22nd biennial examination of the Framingham Cohort. PBMC derived IL-1beta , IL-1Ra, and TNF-alpha production was assessed using a non-cross reacting polyclonal radioimmunoassay. Knee OA was defined as a score of > 2 using a modified Kellgren and Lawrence scale. The presence of osteophytes and joint space narrowing were scored separately on a 0-3 scale, in which disease was defined a priori as a score > 0 for each feature. Sex-specific odds ratios were calculated for knee OA after adjusting for weight, history of knee injury, and use of estrogen and nonsteroidal antiinflammatory drugs. RESULT: No uniform associations were found for IL-1beta or IL-1Ra in men, or for TNF-alpha production and radiographic OA in either sex. We found possible associations for the highest levels of IL-1beta production and the presence of knee osteophytes [OR=2.0 (1.2-3.5)] and joint space narrowing [OR=1.7 (1.1-2.8)] in women. Our data suggested a possible protective effect for IL-1Ra production and hand OA in women [OR=0.6 (0.4-1.0)]. CONCLUSION: We found no consistent association of PBMC cytokine production and radiographic OA. However, women with the highest production of IL-1beta and IL-1Ra had respectively higher rates of knee OA and lower rates of hand OA than expected.  相似文献   
47.
BACKGROUND: Epidemiologic studies are necessary to determine the prevalence of allergic diseases. This varies widely depending on allergen preparations and patients studied. OBJECTIVE: To investigate the prevalence of atopic disease, skin test reactivity, total and specific IgE to common allergens, and other variables in a sample of students from Málaga, southern Spain. METHODS: Three hundred sixty-five students (age 17.9 +/- 1.18) were interviewed by an allergist. Skin prick tests were performed with Dermatophagoides pteronyssinus, Artemisia vulgaris, Plantago lanceolata, Chenopodium album, Olea europaea, Phleum pratense, Parietaria judaica, Cynodon dactylon, Alternaria tenuis, and cat dander. Total and specific IgE to D. pteronyssinus, Olea, and Parietaria were determined. RESULTS: Of all subjects studied, 19.9% suffered from rhinoconjunctivitis, 4.1% rhinoconjunctivitis plus asthma, 3.1% asthma alone, and 0.8% atopic dermatitis; 46.4% had a positive skin test to at least one allergen (28.2% to D. pteronyssinus, 20.4% to Olea, 13.8% to Phleum); and 43% had total IgE > 100 kU/L and 44.7% a family history of atopy. Allergic symptoms were strongly associated with skin test positivities and family allergic history. Patients with asthma or skin prick test positive had higher total IgE values than others (P < .01). There was a significant correlation between specific IgE values and wheal size in skin test. CONCLUSIONS: Our findings confirm the high prevalence of atopic diseases, and the close relationship of skin tests reactivity (or presence of specific IgE) to allergens with symptoms of asthma and rhinitis. The presence of a family history of allergic diseases influences the development of positive skin tests and atopic illness. Dermatophagoides pteronyssinus and pollen of Olea europaea were found to be the most common allergens.  相似文献   
48.
Thirty patients with coronary artery disease (CAD) were administered garlic (study group) while another 30 patients received the placebo (control group). Various risk parameters were determined at 1.5 and 3 months of garlic administration. Garlic, administered in a daily dose of 2 x 2 capsules (each capsule containing ethyl acetate extract from 1 g peeled and crushed raw garlic), reduced significantly total serum cholesterol and triglycerides, and increased significantly HDL-cholesterol and fibrinolytic activity. There was no effect on the fibrinogen and glucose levels. In vitro effects of the garlic oil on platelet aggregation (PAg) and eicosanoid metabolism were examined; it inhibited PAg induced by several platelet agonists, and also platelet thromboxane formation. Two important paraffinic polysulphides - diallyl disulphide (DADS) and diallyl trisulphide (DATS) - derived from garlic and are usual constituents of garlic oil, showed antiplatelet activity, and also inhibited platelet thromboxane formation. In this respect DATS was more potent than DADS. The nature of inhibition of PAg by DATS was found to be reversible.  相似文献   
49.
The ability of recombinant preparations of equine herpesvirus type 1 (EHV-1) glycoprotein D (gD) to elicit specific antibody and T lymphocyte responses in the BALB/c mouse model of respiratory infection was investigated. Recombinant gD (rgD) expressed as a glutathione-S-transferase (GST) fusion protein in Escherichia coli elicited both high titer neutralizing antibody (nAb) and CD4 T cell proliferative responses following subcutaneous or intranasal immunization, but elicited only a weak antibody response after intraperitoneal immunization. Protection against respiratory tract infection with pathogenic EHV-1 RacL11 was observed in mice immunized subcutaneously with GST-gD. Furthermore, the degree of protection correlated to the titer of nAb and the T cell response observed. Finally, GST-gD was more effective in protecting against respiratory RacL11 infection if delivered intranasally. These results confirm that gD plays an important role in eliciting the protective immune response against EHV-1 infection, and indicate that subunit vaccines containing preparations of gD may be very effective if delivered directly to the upper respiratory tract.  相似文献   
50.
OBJECTIVE: To evaluate prospectively a diffractive (811E, Pharmacia; power add +4.0 D) versus a refractive (PA154N, Allergan; power add +3.5 D) designed multifocal lens. PARTICIPANTS: Eighty patients planned for cataract surgery without additional ocular pathologies were randomized into the diffractive or refractive group, respectively. INTERVENTION: A standardized no-stitch phacoemulsification with implantation of one of the two multifocal lenses was performed in each patient. MAIN OUTCOME MEASURES: Distance and near-visual acuity, contrast sensitivity, low contrast visual acuity, glare visual acuity, and depth of focus were measured after surgery. RESULTS: All treated patients had best-corrected visual acuities of 20/30 or better. Near-uncorrected vision was significantly better (P < 0.0001) with the diffractive lens (mean, J1) than with the refractive lens (mean, J4). Low contrast visual acuity (61 +/- 12% versus 59 +/- 9%), glare visual acuity (39 +/- 19% versus 38 +/- 14%), and contrast sensitivity (1.48 +/- 0.08 versus 1.50 +/- 0.12) were not significantly different between the groups. CONCLUSIONS: Both lens designs showed satisfactory functional results with advantages for the diffractive lens design.  相似文献   
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