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101.
Glycoprotein D (gD) of bovine herpesvirus 1 (BHV-1), a homolog of herpes simplex virus gD, represents a major component of the viral envelope and is a dominant immunogen. To study the antigenic properties of the different regions of gD, we have expressed the full-length gD encoding gene and overlapping fragments spanning various regions of the gD open reading frame in a baculovirus (Autographa californica nuclear polyhedrosis virus)--insect cell (Spodoptera frugiperda, SF-9) system. Maximum levels of expression for all proteins were obtained 48 to 72 h post infection of SF-9 cells by recombinant viruses. Full-length and truncated recombinant gD proteins reacted specifically with anti-gD monospecific serum as determined by immunoprecipitation and immunoblotting, indicating that the proteins retained their antigenicity. However, based on the reactivity with a panel of gD-specific monoclonal antibodies (Mabs), the full-length recombinant gD lacked proper expression for two highly neutralizing linear epitopes identified by Mabs R54 and 9D6. The rest of the epitopes appeared to be preserved and antigenically unaltered. Immunofluorescence studies of recombinant baculovirus infected SF-9 cells using gD monospecific serum, revealed no direct correlation between cellular localization of the expressed proteins and their amino acid sequences.  相似文献   
102.
When assuming a species-typical tripodal posture, female Mongolian gerbils most often rest on their left forepaws and hold their right forelimbs aloft; male gerbils most often do the reverse. This experiment examined effects of gonadectomy, both in infancy and in adulthood, on the sexually dimorphic asymmetry in forelimb use by Mongolian gerbils when maintaining a tripodal stance. In adulthood, both male and female gerbils that had been gonadectomized at birth reversed their forelimb use while in a tripodal stance: Gonadectomized males used their forelimbs as did sham-operated females, and gonadectomized females used their forelimbs as did sham-operated males. Gonadectomy in adulthood abolished the sexual dimorphism in forelimb use seen in sham-operated subjects. It was concluded that gonadal hormones have organizational as well as possible activational effects on adult patterns of forelimb use by gerbils.  相似文献   
103.
Electron microscopic investigation of the rabbit [correction of rat] thoracic aorta revealed endothelium to be most vulnerable to the damage in experimental hypercholesterolemia. Administration of precursor of nitric oxide L-arginine against the background of hypercholesterolemia resulted in activation of functional activity of the endothelium of aorta. This notion is supported by an increase of the quantity of protein-synthesizing structures (ribosomes, polysomes, canaliculi of endoplasmic network), secretory granules vs rabbits on atherogenic diet. At stimulation of NO-synthase activity of endothelium the dilatory reactions of aortal strips to acetylcholine are improved.  相似文献   
104.
Before use of cardiovascular surgical techniques and procedures in humans, many experiments, e.g., hypothermic circulatory arrest and cardiopulmonary bypass using the heart-lung machine, have been performed in the dog. As a consequence experimental canine cardiovascular surgery is highly developed. This has not resulted in the routine performance of open heart surgery in veterinary medicine, probably because of the high costs. Cardiovascular surgery in the dog is generally limited to interventions not depending on hypothermic circulatory arrest or cardiopulmonary bypass. The clinical cardiovascular surgery in dogs can be divided into routine and more specialized interventions. The first category includes correction of peritoneopericardial diaphragmatic hernia, pericardial fenestration in dogs with pericardial effusion, treatment of persistent right aortic arch, and patent ductus closure. The specialized interventions include dilation of pulmonic and aortic stenoses and pacemaker implantation. The diagnosis and surgical treatment of such diseases is described. New developments in cardiovascular surgical treatment that can be expected include catheter techniques for occlusion of shunts and dilations using balloons, because the financial costs of these procedures are not prohibitive.  相似文献   
105.
The gene rafY from the plasmid pRSD2, which enables Escherichia coli to grow on raffinose, was transferred into expression plasmid pUSL77. The protein was expressed in the porin-deficient Escherichia coli strain KS26 and was isolated and purified to homogeneity. The pure protein was reconstituted into lipid bilayer membranes. It formed an ion-permeable channel with a single-channel conductance of 2.9 nS of the open state in 1 M KCl, which is approximately twice of that of the general diffusion pores OmpF and OmpC of E. coli outer membrane. At lower pH the channel exhibited rapid flickering between three substates of the open channel. The RafY channel appears to be wide and water filled and has a small selectivity for cations over anions. Although RafY is part of an uptake and fermentation system for raffinose it does not contain a binding site for carbohydrates. Our results suggest that RafY is a general diffusion pore with a diameter, larger than that of the general diffusion porins OmpF and OmpC, that allows the diffusion of high-molecular-mass carbohydrates through the outer membrane.  相似文献   
106.
OBJECTIVE: To determine whether postmenopausal oestrogen replacement therapy affects carotid artery pulsatility index. DESIGN: A prospective double-blind placebo controlled trial. SETTING: University associated teaching hospital. PARTICIPANTS: Twenty-eight postmenopausal women who were more than 12 months postmenopausal and who had not taken exogenous oestrogen. INTERVENTIONS: Independent randomisation to receive oral oestradiol (2 mg daily) or placebo for 20 to 24 weeks. MAIN OUTCOME MEASURES: Internal carotid artery Doppler pulsatility index, measured within one centimetre of the carotid bifurcation. RESULTS: Replicate data were available from 27 women. The mean pulsatility index decreased by -0.11 in 15 women receiving oestradiol, compared with a mean rise of 0.05 in the 12 women who received placebo (P = 0.006, 95% CI for treatment difference 0.06-0.31). CONCLUSIONS: Oestrogen replacement decreases postmenopausal carotid artery pulsatility index, probably reflecting decreased peripheral vascular resistance. This is a further mechanism whereby hormone replacement therapy may impart cardiovascular protection.  相似文献   
107.
108.
BACKGROUND: Antimicrobial therapy is the recommended treatment for duodenal ulcer associated with Helicobacter pylori infection. The eradication of bismuth-based triple therapy with bismuth subcitrate, metronidazole and amoxicillin is limited by low compliance, drug resistance and side-effects. Two-week proton pump inhibitor (PPI)-based triple therapy has a higher eradication rate but is costly. This study was designed to compare the efficacy, patient compliance and cost of short-term PPI-based triple therapy with those of bismuth-based triple therapy. METHODS: Ninety patients with active duodenal ulcer disease and H pylori infection, proven with the 13C-urea breath test and CLO test (Campylobacter-like organism test) were treated randomly in three therapeutic groups: Group A, DeNol 120 mg, amoxicillin 500 mg and metronidazole 250 mg four times a day orally for 14 days; Group B, omeprazole 20 mg plus clarithromycin 500 mg twice a day and amoxicillin 500 mg four times a day for 14 days; Group C, omeprazole 20 mg, clarithromycin 250 mg and metronidazole 500 mg twice a day for seven days. Nizatidine 150 mg twice a day was given continuously following the end of anti-H pylori therapy for each group. Two months later, endoscopy, the CLO test and 13C-urea breath test were repeated to assess the eradication rate of H pylori and the ulcer-healing rate. Drug tolerance was evaluated by patients themselves by daily recording of any side-effects. RESULTS: Eighty-four patients completed the entire course of therapy and evaluation for H pylori infection. The H pylori eradication rates in Groups A, B and C were 75% (21/28), 93% (26/28) and 89% (25/28), respectively (p = 0.466). The ulcer healing rate was 86% (24/28) in Group A and 89% (25/28) in Groups B and C (p = 0.764). A total of 74 patients (88%) were free from symptoms at the end of the triple therapy. Symptom relief was faster in patients with PPI-based triple therapy (Groups B and C) (days 3 and 4) than for patients with bismuth-based triple therapy (day 5). The cost of Group C therapy was lower than that for Groups A and B. There were no major side-effects in any of the patients. CONCLUSIONS: One-week triple therapy with omeprazole, clarithromycin and metronidazole is highly effected for the eradication of H pylori. A therapeutic regime of one week's duration with lower cost, good compliance and mild side-effects may offer a good choice for treatment of duodenal ulcer associated with H pylori infection in clinical practice.  相似文献   
109.
A 28-year-old man presented with selective immunoglobulin A deficiency and severe diarrhea responding to a gliadin-free diet. Biopsy samples of the small intestine showed dense T-cell infiltrations in the lamina propria and a slight increase of intraepithelial T-lymphocytes. No clonal rearrangement of the T-cell receptor c-beta chain genes was detectable by Southern blotting. Four years later, at the age of 32, the patient was hospitalized again with liver failure, abdominal lymphadenopathy, pancytopenia, and recurrent bacterial infections. Retrospective polymerase chain reaction analysis of formalin-fixed tissues of the intestinal biopsy samples obtained 4 years earlier showed monoclonal T-cell receptor gamma-chain gene rearrangement. Lymphoid cells of the peripheral blood showed an immunophenotype of CD3-positive gamma/delta T cells with a negativity for CD4 and CD8. A clonally rearranged T-cell receptor delta chain gene and a germline configuration of the c-beta chain genes was found by Southern blotting. Cytogenetics showed an abnormal karyotype with unbalanced translocations t(1;5) and t(9;13). The patient died of extensive lung infiltrations by gamma/delta T cells; autopsy showed a peripheral T-cell lymphoma of the gamma/delta type in the enlarged abdominal lymph nodes. This is the first report of an abdominal T-cell lymphoma of the gamma/delta type in a patient with selective immunoglobulin A deficiency.  相似文献   
110.
BACKGROUND AND OBJECTIVE: Drug resistance has become a major cause of treatment failure in patients with acute leukemia. P-glycoprotein (Pgp), which is associated with the multidrug resistance (MDR) phenotype, has been reported to be an important predictor of treatment outcome. The aim of this study was to analyze the value of Pgp expression in bone marrow or peripheral blood as a predictor of the response to remission induction chemotherapy as well as the duration of remission in patients with de novo acute myeloid leukemia (AML). DESIGN AND METHODS: We examined the expression of Pgp in 82 patients with de novo AML using an immunocytochemical assay with the C219 monoclonal antibody. RESULTS: Twenty-seven of the 82 patients (33%) were C219-positive in from 1% to 100% of their cells. Thirteen cases (16%) showed a positive reaction in more than 50% of the leukemic cells. Only hyperleukocytosis was significantly associated with higher expression of Pgp. Although 8 of the 13 cases (62%) with more than 50% of cells having Pgp expression were CD34-positive, this association was not statistically significant. A univariate analysis of resistance to induction therapy showed a significantly higher resistance rate in patients with increased Pgp expression (P = 0.01) as well as in those patients with decreased reactivity to myeloperoxidase. The multivariate analysis revealed the independent prognostic value of Pgp expression. C219 reactivity did not have an influence on remission duration. INTERPRETATION AND CONCLUSIONS: Our data indicate that P-glycoprotein expression is a reliable marker of resistance to induction treatment in patients with de novo AML.  相似文献   
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