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991.
The primary IgG, IgM and IgA antibody responses to Helix pommatia haemocyanin (HPH) were defective in patients with ataxia telangiectasia (AT) and Nijmegen breakage syndrome (NBS). The results in patients with Bloom's syndrome (BS) were heterogeneous, but all showed abnormal kinetics of the IgG response. The secondary response to diphtheria, tetanus and polio vaccine was normal in patients with AT and BS, but disturbed in the patients with NBS. The abnormalities of antibody response of AT and NBS are similar, although more profound in NBS; BS is different.  相似文献   
992.
The effects of immunization and anticoagulation in experimental Escherichia coli endocarditis were studied. Immunization of rabbits with E. coli resulted in the development of specific agglutinating and opsonic activity of the serum, but not in bactericidal activity. These antibody activities also developed in nonimmunized rabbits during the course of bactericidal endocarditis. Immune serum promoted phagocytosis in vitro but did not enhance intracellular killing of E. coli by elicited rabbit peritoneal macrophages. The presence of specific antibodies in rabbits after immunization had no effect on the induction or course of E. coli infection of endocardial vegetations. Anticoagulation was found to affect the induction of the infection. In anticoagulated rabbits, larger bacterial inocula were needed to induce an infection, but in animals with bacterial endocarditis the number of bacteria in the vegetations did not differ significantly from that of the control animals.  相似文献   
993.
Searches among mycobacterial cultures for antileprosy vaccines.   总被引:2,自引:5,他引:2       下载免费PDF全文
All mycobacteria species share some antigens, so there may be cultivable mycobacterial cultures that can provide vaccine protection against leprosy. Vaccine protection against Mycobacterium leprae infections in mice has been demonstrated for M. leprae itself, as living or heat-killed suspensions, and for Mycobacterium bovis (BCG), as living suspensions. Results are reported here with 17 other cultures. The mycobacterial suspensions were injected intradermally, and the mice were challenged in the footpad with infectious suspensions of M. leprae. In two experiments the mice were also challenged by footpad injections of 10(7) heat-killed M. leprae so the footpad enlargment could be measured. That some mycobacterial suspensions were immunogenic for some of their own antigens was suggested by reactions at the vaccine site and enlargement of the regional lymph nodes. Some mycobacterial suspensions also stimulated footpad enlargement on challenge by homologous suspensions or by challenge with M. leprae suspensions. Consistent protection against infectious challenge with M. leprae was observed only with BCG and M. leprae, however.  相似文献   
994.
Since nonencapsulated Haemophilus influenzae persists in the lower respiratory tracts of patients with chronic bronchitis despite the presence of specific antibodies, complement, and polymorphonuclear leukocytes (PMNs), opsonophagocytosis of H. influenzae was analyzed. Nonencapsulated H. influenzae isolated from the sputa of chronic bronchitis patients was labeled with fluorescein isothiocyanate and incubated with human PMNs in the presence of complement and antibodies for 30 min at 37 degrees C. Candida albicans was added to each sample as an internal standard, and the reduction of the number of bacteria was determined by flow cytometry. Fluorescence quenching with ethidium bromide was used to discriminate between intracellular and extracellular bacteria. Opsonophagocytosis of viable H. influenzae d1 was 17% +/- 29% in the presence of complement and human pooled sera containing high titers of strain-specific antibodies. Opsonophagocytosis of six other H. influenzae strains was also poor. Under the same conditions, opsonophagocytosis of Staphylococcus aureus was 90% +/- 5%, and opsonophagocytosis of C. albicans was 55% +/- 23%. About half of the number of H. influenzae bacteria associated with PMNs was internalized. Opsonophagocytosis of heat-killed H. influenzae d1 (41% +/- 20%) was higher than that of viable bacteria of the same strain (P < 0.05). This result suggests that the accessibility of epitopes on H. influenzae for opsonizing antibodies is better on killed than on viable bacteria. We conclude that viable nonencapsulated H. influenzae is poorly opsonophagocytized in the presence of strain-specific antibodies and complement.  相似文献   
995.
In comparison with the classical immunisation schedules (0-1-6 or 0-1-12 months) for hepatitis A, a 0- and 12- or a 0- and 6-month schedule would have important advantages by reducing the number of injections and discomfort and increasing scheduling convenience and patient compliance. It would be convenient if a single dose with enough antigen could protect both rapidly and for at least 12 months, when the booster dose would be given. Several clinical trials have been carried out with an inactivated hepatitis A vaccine containing 1,440 ELU. (1 ml), according to a 0–12 and a 0–6 vaccination schedule. This hepatitis A vaccine is safe and well tolerated. It offers a rapid seroresponse: 14 days after a single dose the seroconversion is 88% (95% C.I.: 84.6–90.9). The 0–12 schedule study showed good persistence of hepatitis A virus (HAV) antibodies with a seroconversion rate of almost 95% at month 12. Booster doses given at 6 or 12 months result in a substantial rise in antibody levels; according to these antibody litres, the 1,440 EL. U. vaccine can be expected to confer comparable duration of protection as the 720 EL. U. vaccine, i.e., 10–20 years. Preliminary data show that tinning of the booster may not be critical for the antibody response. In conclusion, the 1,440 EL. U. hepatitis A vaccine is safe, offers rapid seroconversion, and is highly immunogenic. The persistence of HAV antibodies until month 12 allows a certain flexibility in the administration of the booster: month 6 or 12, and a 0–12 or 0–6 schedule can increase the vaccination compliance. copy; 1994 Wiiey-Liss, inc.  相似文献   
996.
In order to summarize the available clinical evidence for the efficacy of physiotherapy, 400 randomized clinical trials were identified from the literature. Studies were found by using bibliographic databases, citation tracking, and correspondence with researchers in the field. Focusing on disorders of the musculoskeletal system, a number of criterion based meta-analyses were performed on 180 trials in order to summarize the available evidence. For each randomized clinical trial in each meta-analysis a methodological score was calculated using a set of explicit criteria and weighting factors applied by two or three independent reviewers who were blinded as to the outcomes, the journal and the authors of the publication. In each meta-analysis the randomized clinical trials were ordered hierarchically depending on their score for methodological quality. Meta-analyses were performed for spinal manipulation, exercise therapy, traction, ultrasound, and laser therapy, and for disorders of the back, neck, shoulder and knee. In general, the methodological quality of the studies appeared to be low, and the efficacy of physiotherapy was shown to be convincing for only a few indications and treatments. On the other hand, because of the prevalence of serious methodological flaws, it cannot be concluded that physiotherapy has no effect.  相似文献   
997.
998.
Recent studies consider lifestyle risk score (LRS), an aggregation of multiple lifestyle exposures, in identifying association of gene-lifestyle interaction with disease traits. However, not all cohorts have data on all lifestyle factors, leading to increased heterogeneity in the environmental exposure in collaborative meta-analyses. We compared and evaluated four approaches (Naïve, Safe, Complete and Moderator Approaches) to handle the missingness in LRS-stratified meta-analyses under various scenarios. Compared to “benchmark” results with all lifestyle factors available for all cohorts, the Complete Approach, which included only cohorts with all lifestyle components, was underpowered due to lower sample size, and the Naïve Approach, which utilized all available data and ignored the missingness, was slightly inflated. The Safe Approach, which used all data in LRS-exposed group and only included cohorts with all lifestyle factors available in the LRS-unexposed group, and the Moderator Approach, which handled missingness via moderator meta-regression, were both slightly conservative and yielded almost identical p values. We also evaluated the performance of the Safe Approach under different scenarios. We observed that the larger the proportion of cohorts without missingness included, the more accurate the results compared to “benchmark” results. In conclusion, we generally recommend the Safe Approach, a straightforward and non-inflated approach, to handle heterogeneity among cohorts in the LRS based genome-wide interaction meta-analyses.Subject terms: Genetics, Risk factors  相似文献   
999.
BACKGROUND: Eliciting an endogenous LH surge by GnRH-agonist for the induction of final oocyte maturation may be more physiological compared with the administration of HCG. However, the efficacy of this intervention in patients treated for IVF with GnRH antagonists remains to be assessed. METHODS: 106 patients were randomized to receive either 10 000 IU urinary HCG or 0.2 mg Triptorelin for triggering final oocyte maturation. Ovarian stimulation for IVF was performed with a fixed dose of 200 IU recombinant FSH and GnRH antagonist was started on stimulation day 6. Luteal phase was supported with micronized vaginal progesterone and oral estradiol. The study was monitored continuously for safety and stopping rules were established. RESULTS: No significant differences were present in the number of cumulus-oocyte complexes retrieved, in the proportion of metaphase II oocytes, in fertilization rates or in the number and quality of the embryos transferred between the two groups. However, a significantly lower probability of ongoing pregnancy in the GnRH agonist arm prompted discontinuation of the trial, according to the stopping rules established (odds ratio 0.11; 95% confidence interval 0.02-0.52). CONCLUSIONS: Lower probability of ongoing pregnancy can be expected when GnRH agonist is used for triggering final oocyte maturation instead of HCG in patients undergoing ovarian stimulation for IVF with GnRH antagonists.  相似文献   
1000.
Serum carcinoembryonic antigen concentrations (serum CEA) in 80 patients with primary breast cancer were measured preoperatively, one month after operation, and thereafter serially every third month. These data were related to histological and morphometric features of the primary breast carcinoma and the lymph node metastases and to clinical follow up data. Analysis of the serum CEA values showed significant correlations with size of tumour, the presence of lymph node metastases, oestrogen receptor, and occurrence of distant metastases. Furthermore, the results indicated that serial determination of serum CEA in the first two years after operation may be useful in monitoring for the occurrence of distant metastases in patients with metastatic spread to lymph nodes and with large (greater than or equal to 2 cm) primary breast tumours positive for oestrogen receptor. In agreement with other studies, however, it was found that the predictive value of serum CEA concentrations in general is weak and costs may prohibit the implementation of the routine assessment of CEA concentrations.  相似文献   
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