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91.
The objective of this study was to determine outcomes of referring drug users (DUs) with chronic hepatitis C for clinical evaluation and care. Two hundred twenty-eight persons with detectable hepatitis C virus RNA were given expedited referrals for evaluation and possible treatment of hepatitis C from a prospective study cohort of current and former opiate-addicted DUs. Four outcomes were analyzed: accepted referral, arrived for clinical evaluation, had liver biopsy, and received treatment. One hundred twenty-seven participants (56%) accepted referral, of whom 54 (43%) arrived for evaluation. Of these participants, 12 (22%) had liver biopsy, and 4 (7%) were treated. Multivariate logistic regression revealed that HIV-infected DUs were significantly less likely to accept referral (adjusted odds ratio [O(Radj)], 0.51; 95% confidence interval [CI], 0.30-0.88), and older participants were more likely to keep an appointment (O(Radj), 1.06/y; 95% CI, 1.00-1.12). Of HIV-seropositive participants, those with a history of injection were more likely to accept referral (O(Radj), 3.60; 95% CI, 1.08-11.96), and those with higher HIV load (O(Radj), 0.50/log10; 95% CI, 0.26-0.94) and Hispanic ethnicity (O(Radj), 0.26; 95% CI, 0.07-0.89) were less likely to keep an appointment. Despite expedited referrals for hepatitis C care, only a few participants received an evaluation, and even far fewer were treated. Because increasingly effective treatment is available, better methods are urgently needed to improve evaluation and treatment of HCV-infected DUs, including those coinfected with HIV.  相似文献   
92.
Rheumatoid factor-like substances were induced in rabbits by infection with Trypanosoma equiperdum. There was a certain parallelism with the phenomena described earlier with T. gambiense infections in man. The anti-IgG globulins were IgM with a preference for heterologous (human) IgG in the latex fixation test. A correlation was found between the latex fixation titres and the IgM levels in the sera. A naturally occurring pre-infectious agglutinator was not of IgM nature. The anti-IgG globulins developed in all the infected animals, mostly within 2 weeks and often before the IgG levels in the sera started to increase.

The failure to induce rheumatoid factor-like substances in mice infected with a certain strain of T. gambiense indicates the importance of the host–parasite relationship for the formation of rheumatoid factors.

The single radial diffusion method according to Mancini, Carbonara & Heremans (1965) did not give valid results for the determination of IgM in the rabbit sera, but could be used for IgG. IgM was determined by an indirect method.

These experiments might form the basis of a model for investigating the nature of rheumatoid factor formation.

  相似文献   
93.
The family of epithelial Ca(2+) channels (ECaC) is a unique group of highly Ca(2+)-selective channels consisting of two members, ECaC1 and ECaC2. We used carboxyl terminal truncations and mutants to delineate the molecular determinants of the Ca(2+)-dependent inhibition of ECaC. To this end, rabbit ECaC1 was expressed heterologously with green fluorescent protein (GFP) in human embryonic kidney 293 (HEK293) cells using a bicistronic vector. Deletion of the last 30 amino acids of the carboxyl terminus of ECaC1 (G701X) decreased the Ca(2+) sensitivity significantly. Another critical sequence for Ca(2+)-dependent inactivation of ECaC1 was found upstream in the carboxyl terminus. Analysis of truncations at amino acid 635, 639, 646, 649 and 653 disclosed a critical sequence involved in Ca(2+)-dependent inactivation at positions 650-653. C653X showed decreased Ca(2+) sensitivity, comparable to G701X, while E649X lacked Ca(2+)-dependent inactivation. Interestingly, the number of green fluorescent cells, which is an index of the number of transfected cells, was significantly smaller for cells transfected with truncations shorter than E649 than for cells transfected with wild-type ECaC. However, the expression level of GFP was restored in the presence of the ECaC blocker ruthenium red, suggesting that these truncations resulted in deleterious Ca(2+) influx. In conclusion, we have identified two domains in the carboxyl terminus of ECaC1 that control Ca(2+)-dependent inactivation.  相似文献   
94.
Genetic transfer of guanidine resistance from type 2 to type 1 poliovirus   总被引:1,自引:0,他引:1  
Summary Following mixed infection of monkey kidney cells with a guanidine-sensitive clonal derivative of the attenuated LSc2ab type 1 poliovirus strain and with a guanidine-resistant clonal derivative of the MEF1 type 2 strain, the frequency of guanidine-resistant type 1 particles was found to be increased in the progeny. The frequency of these particles was almost 4 times higher than that of spontaneous mutants in the progeny of the self cross. This difference being statistically significant it is considered to be an argument in favour to the occurrence of recombination between the two serologically unrelated poliovirus strains.Investigation of a group of unselected genetic markers in the type 1 guanidine-resistant clonal strains derived from the progeny of mixed infection showed that transfer of guanidine resistance from the type 2 parental strain was not associated with the transfer of any other character of this strain.  相似文献   
95.
Major depression is conditionally linked to a polymorphism of the human serotonin transporter gene (SLC6A4). During the presentation of aversive, but not pleasant, pictures, healthy carriers of the SLC6A4 short (s) allele showed stronger activation of the amygdala on functional magnetic resonance imaging. s carriers also showed greater coupling between the amygdala and the ventromedial prefrontal cortex, which may contribute to the abnormally high activity in the amygdala and medial prefrontal cortex seen in major depression.  相似文献   
96.
97.
Keloid and hypertrophic scars are relatively frequent not wanted consequences of surgical treatment. 145 patients with unsatisfactory skin healing were treated in our department during last 5 years. When compared with corticotherapy and laser-therapy kryotherapy is very effective method. There were outstanding results with combination of cryotherapy and corticotherapy.  相似文献   
98.
Risk of infection after penetrating abdominal trauma   总被引:12,自引:0,他引:12  
To identify the risk factors for the development of postoperative septic complications in patients with intestinal perforation after abdominal trauma, and to compare the efficacies of single-drug and dual-drug prophylactic antibiotic therapy, we studied 145 patients who presented with abdominal trauma and intestinal perforation at two hospitals between July 1979 and June 1982. Logistic-regression analysis showed that a higher risk of infection (P less than 0.05) was associated with increased age, injury to the left colon necessitating colostomy, a larger number of units of blood or blood products administered at surgery, and a larger number of injured organs. The presence of shock on arrival, which was found to increase the risk of infection when this factor was analyzed individually, did not add predictive power. Patients with postoperative sepsis were hospitalized significantly longer than were patients without infection (13.8 vs. 7.7 days, P less than 0.0001). Both treatment regimens--cefoxitin given alone and clindamycin and gentamicin given together--resulted in similar infection rates, drug toxicity, duration of hospitalization, and costs.  相似文献   
99.
P Aman  J Gordon  G Klein 《Immunology》1984,51(1):27-34
The effect of the tumour-promoting phorbol ester TPA (12-O-tetradecanoyl-phorbol-13-acetate) on normal human peripheral blood and tonsil B lymphocytes was investigated. A strong DNA-synthesis response with the maximum at day 4 was detected. This response was, however, inhibited by increasing concentrations of serum in the medium. The membrane Ig expression was changed with a rapid decrease in IgD expression and a slower decrease in IgM and IgG expression. TPA-induced Ig secretion was detected in 12 out of 22 tested donors and the response was found to be independent of T cells and macrophages. The expression of four monoclonal antibody-detected B cell activation and differentiation markers, B1, B2, LB1 and BB1, was followed. The results indicate activation and differentiation of the B cells.  相似文献   
100.
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