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71.
BACKGROUND: Infection with cancer-linked human papillomavirus (HPV) types such as HPV type 16 (HPV16) is the most important risk factor in the development of cervical cancer. It has been shown that immunoglobulin G (IgG) antibody responses against HPV16 virus-like particles (VLPs) are specifically associated with genital HPV16 infection. PURPOSE: The aim of this study was to determine the temporal relationships between the presence of HPV16 VLP-specific IgGs, HPV16 infection patterns, and the course of premalignant cervical disease. METHODS: Plasma samples from 133 women who had been diagnosed originally with mild to moderate cervical dyskaryosis and enrolled in a prospective non-intervention cohort study conducted in Amsterdam, The Netherlands, from 1991 through 1996 were analyzed for the presence of HPV16 VLP-specific IgGs by use of an enzyme-linked immunosorbent assay. A detailed analysis was performed on 43 women with different HPV16 infection patterns during a follow-up period of 10-34 months. Progression or regression of cervical intraepithelial neoplasia (CIN) lesions was monitored by cytologic and colposcopic testing at intervals of 3-4 months. HPV typing in cervical smears was performed by use of a polymerase chain reaction-based assay. Statistical analysis of the serologic data was performed by use of the Mann-Whitney U test or 2 x 2 table analyses. RESULTS: The presence of HPV16 VLP-specific IgGs in the plasma of the patients was found to be associated with the presence of HPV16 DNA in the cervical smear. Significantly higher proportions of patients with persistent HPV16 infections (i.e., who were polymerase chain reaction positive in three to 11 consecutive tests) than of patients with cleared HPV16 infections were found to be positive for the presence of HPV16 VLP-specific IgGs (18 [69.2%] of 26 versus nine [28.1%] of 32, respectively; P = .003). HPV16 VLP-specific IgGs were consistently detected in all women (n = 11) who were persistently HPV16 DNA positive during follow-up and whose disease ultimately progressed to CIN III (histologically diagnosed severe dysplasia or carcinoma in situ). CONCLUSION: HPV16 VLP-specific IgG responses are present in the plasma of a majority of patients with persistent HPV16 infections and histologically confirmed high-grade lesions but only in a smaller subset of patients with cleared HPV16 infections and either normal cervical histology or low-grade CIN lesions. IMPLICATIONS: These results suggest that HPV16 VLP-specific antibodies are not responsible for the clearance of virally induced CIN lesions but that they might, in patients with persistent HPV16 infections, be indicative of an increased cervical cancer risk.  相似文献   
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Here, we review the role of total body irradiation in the treatment of children with bone marrow transplantation, as well as alternative sources of stem cells. We were unable to demonstrate any clear superiority of TBI-containing preparative regimens, but we were able to find a few definitive reports of significantly enhanced toxicity or important variations in control of the underlying primary diseases, in comparing TBI-based regimens, with those containing only chemotherapy.  相似文献   
74.
This population-based case-control study was conducted in three countries in western Washington State to evaluate associations between workplace exposures and the risk of amyotrophic lateral sclerosis (ALS). Cases (n = 174) were all newly diagnosed with ALS by neurologists during 1990-1994, and controls (n = 348), who were matched according to age (+/-5 years) and sex, were identified via random-digit dialing or Medicare enrollment files. Four industrial hygienists blindly assessed detailed lifetime job histories for exposures to metals, solvents, and agricultural chemicals. Case-control comparisons were made for jobs held between 15 years of age and 10 years prior to the cases' dates of diagnosis. After adjustment for age and education, ever exposure to agricultural chemicals was associated with ALS (odds ratio (OR) = 2.0, 95% confidence interval (CI) 1.1-3.5); this association was observed separately in men (OR = 2.4, 95% CI 1.2-4.8) but not in women (OR = 0.9, 95% CI 0.2-3.8). Among men, the odds ratio for low exposure to agricultural chemicals (below the median level for exposed controls) relative to no exposure was 1.5 (95% CI 0.4-5.3), and for high exposure, it was 2.8 (95% CI 1.3-6.1) (p for trend = 0.03). Similar analyses based on the panel's assessment of exposures to metals and solvents showed no associations. These findings suggest an association between ALS and agricultural chemicals in men.  相似文献   
75.
The gene encoding the P6-like protein of Pasteurella multocida was cloned in the baculovirus expression system. Baculovirus-expressed recombinant protein was used to parenterally immunize 6-wk-old Nicholas broad-breasted white turkeys. Turkeys developed significant antibody titers to the recombinant protein as measured by enzyme-linked immunosorbent assay. Two weeks after the last immunizing injection, vaccinated turkeys were placed in contact with turkeys infected with P. multocida strain P1059, as were nonvaccinated control birds. No differences occurred in percent mortality between the two groups. We conclude that parenterally administered recombinant P6-like protein does not protect turkeys from avian cholera.  相似文献   
76.
Genomic DNA from 23 patients with isolated growth hormone (GH) deficiency (12 males and 11 females: heights -4.9 +/- 1.4 SDS) was screened for GH gene deletions by restriction endonuclease analysis of polymerase chain reaction amplification products. Three unrelated patients had typical features of severe GH deficiency and deletions (6.7 kb in two and 7.6 kb in one) of the GH gene. The two patients with 6.7-kb deletions developed growth-attenuating anti-GH antibodies whereas the patient with the 7.6-kb deletion continued to grow with GH replacement therapy. Our finding that 3/23 (approximately 13%) Brazilian subjects had GH gene deletions agrees with previous studies of severe isolated GH deficiency subjects in other populations. Two of three subjects (67%) with deletions developed blocking antibodies despite administration of exogenous GH at low doses. Interestingly, only 1/10 of cases with affected relatives or parental consanguinity had GH-1 gene deletions.  相似文献   
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BACKGROUND: Sevoflurane has a lower blood:gas partition coefficient than isoflurane, which may cause a more rapid recovery from anesthesia; it also might cause faster emergence times than for propofol-based anesthesia. We evaluated a database that included recovery endpoints from controlled, randomized, prospective studies sponsored by Abbott Laboratories that compared sevoflurane to isoflurane or propofol when extubation was planned immediately after completion of elective surgery in adult patients. METHODS: Sevoflurane was compared to isoflurane in eight studies (N=2,008) and to propofol in three studies (N=436). Analysis of variance was applied using least squares method mean values to calculate the pooled mean difference in recovery endpoints between primary anesthetics. The effects of patient age and case duration also were determined. RESULTS: Sevoflurane resulted in statistically significant shorter times to emergence (-3.3 min), response to command (-3.1 min), orientation (-4.0 min) and first analgesic (-8.9 min) but not time to eligibility for discharge (-1.7 min) compared to isoflurane (mean difference). Times to recovery endpoints increased with increasing case duration with isoflurane but not with sevoflurane (patients receiving isoflurane took 4-5 min more to emerge and respond to commands and 8.6 min more to achieve orientation during cases longer than 3 hr in duration than those receiving sevoflurane). Patients older than 65 yr had longer times to orientation, but within any age group, orientation was always faster after sevoflurane. There were no differences in recovery times between sevoflurane and propofol. CONCLUSIONS: Recovery from sevoflurane was 3-4 min faster than with isoflurane in all age groups, and the difference was magnified in longer-duration surgical cases (> 3 hr).  相似文献   
80.
Treatment of rats with cytokines has been associated with an increase in the circulating levels of endothelin 1 (ET-1). Here we show that administration of tumor necrosis factor alpha (TNF-alpha; 4 micrograms.kg-1) to anesthetized rats caused within 15 min a strong elevation in the circulating levels of ET-1. This was associated with a striking coronary vasoconstriction in hearts from these animals when they were removed and perfused in vitro by the Langendorff technique. This vasoconstriction was largely overcome by treatment with either the endothelin type A (ETA) receptor antagonist FR 139317 or antibody against ET-1. Furthermore, it was mimicked by in vivo exposure to exogenous ET-1. Endogenously produced TNF-alpha may also cause such a coronary vasoconstriction, for treatment with interleukin 2 (600 micrograms.kg-1) produced an increase in coronary perfusion pressure that correlated with the increases in circulating TNF-alpha. This coronary vasoconstriction was substantially reversed by treatment either with antibody against TNF-alpha or with FR 139317. We suggest, therefore, that cytokine-driven changes in the production of ET-1 are key events in the development of vascular pathologies.  相似文献   
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