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排序方式: 共有1162条查询结果,搜索用时 15 毫秒
1.
Fathi A Elshazly Walid K Abdelbasset Ragab K Elnaggar Sayed A Tantawy 《African health sciences》2020,20(1):368
BackgroundSecond-hand smoking or environmental tobacco smoke is a critical health risk. Children are the most vulnerable to second-hand smoking because of their small bronchial ducts, less developed immunity, and low-physical activity.ObjectivesThe purpose of this study was to ascertain the effects of second-hand smoking on lung functions in athlete and non-athlete school-aged children.MethodsThis observational study included forty-six school-aged children, their age was 8–15 years, assigned to three groups; 2 study groups and 1 control group (n=15). The study groups comprised of 16 football players, and of 15 cyclists. Lung functions were evaluated recording forced vital capacity, forced expiratory volume in 1 sec and peak expiratory flow using digital spirometer.ResultsAll measures were recorded in definite values and the children were also classified into second-hand smoking (SH), or non-exposed to tobacco smoking (NE). The findings presented a significant increase (p<0.05) of the study groups in forced vital capacity, forced expiratory volume in 1 sec and peak expiratory flow solely for the non-exposed children. However, there were non-significant differences between the cyclists and football players or between the passive smoking children and non-exposed children in any of the two study groups (p>0.05).ConclusionThe outcomes of this study suggest beneficial influences of the sports activity on the lung functions, without different influences of the cyclists and football players on the lung functions. 相似文献
2.
Naomi M. Morris M.D. M.P.H. J. Richard Udry Ph.D. Firyal Khan-Dawood Ph.D. M. Yusoff Dawood M.D. 《Archives of sexual behavior》1987,16(1):27-37
The purpose of the study was to attempt to replicate a finding of Persky et al. (1978) that midcycle peak values of testosterone (T) in women predicted differences in frequency of intercourse among married couples. Luteinizing hormone (LH), total testosterone (TT), and free testosterone (FT) values from 10 to 14 daily midcycle blood samples donated by 43 volunteering wives were analyzed against sexual activity patterns reported by the couples over a longer period of time. All couples were contracepting by means other than exogenous hormones or the rhythm method. Each morning through three menstrual cycles husbands and wives recorded independently and on separate forms answers to a series of questions concerning sexual activity in the previous 24 hr. Wives also recorded basal body temperatures (BBT). We designated midcycle values of TT and FT according to several definitions of midcycle. Total testosterone levels at the day of the BBT nadir and the day before the nadir correlated significantly with average intercourse frequency. Correlations with FT were statistically significant regardless of which midcycle measure was used; the day before the BBT nadir gave the highest correlation, 0.618, p = 0.01. Mean testosterone (TT or FT) values were not significantly related. We conclude that female midcycle total testosterone or free testosterone is indexing some unobserved event that affects the frequency of intercourse of couples. We speculate that this event affects the motivation of females, which influences the set point of the compromise frequency characteristic of couples.Research supported in part by NICHD Grant No. 1-R01-HDO7454-01. 相似文献
3.
An indirect competitive ELISA was developed for the quantitative analysis of aldrin/dieldrin. This has been used to monitor the levels of these pesticides in water samples collected in Egypt. The detection range of the aldrin/dieldrin assay in water was 5–10 ppm without enhancement. River Nile water samples and tap water samples (n = 25) were collected from 25 stations in 16 different governorates in Egypt. Pesticides were detected in 10 of the 25 Nile water samples (40%) at levels from 10 to 110 ppb. In tap water samples, pesticides were not detected at levels greater than the lower limit of the assay. The technique described provides a rapid, economical, highly sensitive and specific method of analysis that is relatively simple to perform and interpret. It will be extremely useful in monitoring levels of pesticides in water used for human consumption. 相似文献
4.
C S Alvarado H W Findley W C Chan R S Hnath A Abdel-Mageed R C Pais M H Kutner A H Ragab 《Cancer》1989,63(1):83-89
Natural killer (NK) cells and NK cell activity were determined in three groups (newly diagnosed [n = 21], on therapy [n = 21], and off therapy [n = 18]) of children with various types of malignant solid tumors and in a control group (n = 26) by means of Leu-7 and Leu-11b monoclonal antibodies and a 4-hour 51Cr-release assay, respectively. The erythroleukemia cell line K562 was used as a target cell. The newly diagnosed group included eight patients with localized disease (Stage I-II), ten with bulky but nonmetastatic disease (Stage III), and three with metastases (Stage IV). The mean percent of NK cell activity in the newly diagnosed group was significantly higher than that of the control group. Children with Stage III tumors at diagnosis had higher mean NK cell function than those with Stage I-II and Stage IV. On therapy patients had significantly fewer NK cells and lower NK cell cytotoxicity than those in the other groups studied. We also studied the following: (1) the in vitro effect of recombinant interferon-alpha (rIFN-alpha) and recombinant interleukin-2 (rIL-2) on NK cell function of peripheral blood lymphocytes (PBL) from children with solid malignancies; and (2) the susceptibility of neuroblastoma-derived (CHP-126 and SKNSH) and rhabdomyosarcoma-derived (A-204) cell lines to NK cell lysis. Both rIFN-alpha and rIL-2 enhanced NK cell activity of PBL from children with malignancies and healthy children against K562 and solid tumor cell lines. The enhancing effect or rIL-2 was greater than that of rIFN-alpha. CHP-126 and SKNSH cell lines were susceptible to NK cell lysis mediated by the PBL of children with neuroblastoma and the control group. The A-204 cell line was less sensitive than K562 to NK cell cytotoxicity. Our results suggest a potential therapeutic role for both cytokines in the treatment of malignant solid tumors of childhood. 相似文献
5.
Morphologic discordance in acute leukemia 总被引:1,自引:0,他引:1
6.
The prototypical cutaneous manifestations of human parvovirus B19 (B19) infection include a petechial eruption in a glove and stocking distribution, reticular truncal erythema, and the "slapped cheek" sign. An association with connective tissue disease (CTD) stigmata has recently been made. The clinical and dermatopathologic findings in 14 patients whose skin lesions were accompanied by serological evidence of B19 infection or documentation of B19 genome in lesional skin are presented. The authors encountered skin biopsy specimens from 14 patients who presented with skin eruptions accompanied by clinical signs or serology suggestive of antecedent B19 infection. Clinical findings were correlated to the light microscopic appearance of the lesions and the presence of B19 genome in lesional skin. The study group comprised 9 women, 3 men, and 2 boys. Eruptions characteristic of fifth disease, including the slapped cheek sign, reticulated truncal erythema, and acral petechiae, were present in 3 patients, 1 of whom later developed granuloma annulare. The other patients had atypical clinical presentations comprising an asymptomatic papular eruption (2), an eruption clinically resembling Sweet's syndrome (3), myopathic dermatomyositis (DM) (2), lupus erythematosus (LE)-like syndromes (2), and lower-extremity palpable purpura (2). Skin biopsy specimens in 12 cases showed interstitial histiocytic infiltrates with piecemeal fragmentation of collagen and a mononuclear cell-predominant vascular injury pattern. Other features included an interface dermatitis, eczematous alterations, and papillary dermal edema. Lesions with features of DM or LE also showed mesenchymal mucinosis, whereas a biopsied lesion of palpable purpura showed leukocytoclastic vasculitis (LCV). Immunofluorescent testing showed a positive lupus band test (LBT) with epidermal IgG and C5b-9 decoration in 1 patient with a systemic LE-like illness, whereas the DM patients had negative LBTs and vascular C5b-9 deposition typical for DM. Skin biopsy specimens from 11 patients, including those whose presentations resembled LE and DM, were positive for B19 genome. The dermatopathology of B19 infection suggests tissue injury mediated by delayed-type hypersensitivity, by antibody-dependent cellular immunity directed at microbial antigenic targets in the epidermis and endothelium, and by circulating immune complexes in the setting of LCV. These mechanisms appear to generate a clinical and histopathological picture that recapitulates that of CTD. 相似文献
7.
8.
Azza M. A. Ibrahim A. A. Ragab M. A. Morsy M. M. Hewedi C. J. Smith 《Food and Agricultural Immunology》1994,6(1):39-44
This paper details the results obtained when a number of egg samples, collected in Egypt from different races of chicken were analyzed for the presence of the organochlorine insecticides aldrin and dieldrin. A simple ELISA was used for the detection and quantification of aldrin and dieldrin. The test was modified for application in this high protein system. Pesticide was detected in 83–352% (14/17) of the samples at levels ranging from 0.006 to 0.7 ppm (0.006 to 0.7 μg ml‐1). People eating eggs containing these amounts of pesticides which are above the World Health Organisation average daily intake levels would be at increased risk. 相似文献
9.
Brahmbhatt S Hussain R Zafar S Dawood G Ottenhoff TH Drijfhout JW Bothamley G Smith S Lopez FV Dockrell HM 《Clinical and experimental immunology》2002,128(1):140-148
In order to identify T cell epitopes within the Mycobacterium leprae 45-kD serine-rich antigen, we analysed responses to overlapping 17-mer peptides encompassing the whole antigen in non-exposed UK controls, Pakistani leprosy patients and tuberculosis patients in both the United Kingdom and Pakistan. This antigen has been described as M. leprae-specific, although it has a hypothetical homologue in M. tuberculosis. Human peripheral blood mononuclear cells were stimulated with peptide for 5 days and IFN-gamma measured in supernatants by ELISA. Some peptides were recognized more frequently by T cells from tuberculoid leprosy patients than those from UK controls, suggesting that such T cell epitopes might have diagnostic potential, while other peptides induced greater responses among UK control subjects. Short-term cell lines confirmed that these assays detected specific T cell recognition of these peptides. However, many tuberculosis patients also recognized these potentially specific peptides suggesting that there could be a true homologue present in M. tuberculosis. 相似文献
10.
Wanitchaya Kittikraisak Podjanee Phadungkiatwatana Darunee Ditsungnoen Surasak Kaoiean Louis Macareo Kamonthip Rungrojcharoenkit Nattinee Srisantiroj Tawee Chotpitayasunondh Fatimah S. Dawood Joshua A. Mott Kim A. Lindblade 《Vaccine》2021,39(1):18-25
BackgroundWe compared cord blood antibody titers in unvaccinated pregnant women to those vaccinated with seasonal influenza vaccine during the 2nd and the 3rd trimesters.MethodsPregnant women had cord blood collected at delivery for hemagglutination inhibition assay against vaccine reference viruses: A/California/07/2009 (H1N1)pdm09, A/Switzerland/9715293/2013 (H3N2), and B/Phuket/3073/2013 (Yamagata lineage). Geometric mean titer (GMT) ratios were calculated comparing vaccinated versus unvaccinated pregnant women, and women vaccinated in the 2nd and the 3rd trimesters. Proportions of women achieving defined titers were compared using the χ2 test.ResultsOf 307 women, 190 (62%) were unvaccinated. Fifty and 67 were vaccinated during the 2nd and the 3rd trimesters, respectively. Median enrollment age was 29 years (interquartile range 24–34). Sixteen (5%) women had pre-existing conditions, but none were immunocompromised. GMT ratios comparing vaccinated and unvaccinated women were 5.90 (95% confidence interval [CI] 5.06–6.96) for influenza A/California, 5.39 (95% CI 4.18–6.08) for influenza A/Switzerland, and 5.05 (95% CI 4.43–5.85) for influenza B/Phuket. Similarly, the GMT ratios comparing the 3rd and the 2nd trimester vaccinated women were 2.90 (95% CI 2.54–3.39), 2.82 (95% CI 2.56–3.13), and 2.83 (95% CI 2.56–3.14), respectively. The proportions of women with defined titers for the three vaccine reference viruses did not differ between 2nd and 3rd trimester vaccinated women (titers ≥40: 68–92% versus 70–93%; ≥110: 32% versus 33–63%; and ≥330: 4–10% versus 3–21%).ConclusionsPregnant women vaccinated against influenza had more placental transfer of influenza antibodies to their infants than unvaccinated women. Placental transfer of antibodies was higher among those vaccinated in the 3rd trimester than in the 2nd trimester. There was no difference in the proportions of women achieving antibody titers corresponding to protection against influenza in children. Findings support the current World Health Organization’s recommendation that pregnant women may be vaccinated in either 2nd or 3rd trimester of pregnancy. 相似文献