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21.
JM Langley JC LeBlanc EE Wang BJ Law NE MacDonald I Mitchell D Stephens J McDonald FD Boucher S Dobson 《Pediatrics》1997,100(6):943-946
OBJECTIVE: To determine nosocomial transmission of respiratory syncytial virus (RSV) in Canadian pediatric hospitals, outcomes associated with nosocomial disease, and infection control practices. DESIGN: A prospective cohort study in the 1992 to 1994 winter respiratory seasons. SETTING: Nine Canadian pediatric university-affiliated hospitals. PARTICIPANTS: Hospitalized children with symptoms of lower respiratory tract infection (at least one of cough, wheezing, dyspnea, tachypnea, and apnea) and RSV antigen identified in a nasopharyngeal aspirate. RESULTS: Of 1516 children, 91 (6%) had nosocomial RSV (NRSV), defined as symptoms of lower respiratory tract infection and RSV antigen beginning >72 hours after admission. The nosocomial ratio (NRSV/[com-munity-acquired RSV {CARSV})] + NRSV) varied by site from 2.8% to 13%. The median length of stay attributable to RSV for community-acquired illness was 5 days, but 10 days for nosocomial illness. Four children with NRSV (4. 4%) died within 2 weeks of infection, compared with 6 (0.42%) with CARSV (relative risk = 10.4, 95% confidence interval: 3.0, 36.4). All sites isolated RSV-positive patients in single rooms or cohorted them. In a multivariate model, no particular isolation policy was associated with decreased nosocomial ratio, but gowning to enter the room was associated with increased risk of RSV transmission (incidence rate ratio 2.81; confidence interval: 1.65, 4.77). CONCLUSIONS: RSV transmission risk in Canadian pediatric hospitals is generally low. Although use of barrier methods varies, all sites cohort or isolate RSV-positive patients in single rooms. Children with risk factors for severe disease who acquire infection nosocomially have prolonged stays and excess mortality. 相似文献
22.
The potential repercussions of maternal, fetal, and neonatal hypothyroxinemia on the progeny. 总被引:17,自引:0,他引:17
The adequate functioning of both the maternal and fetal thyroid glands play an important role to ensure that the fetal neuropsycho-intellectual development progresses normally. Three sets of clinical disorders are considered, that may eventually lead to impaired brain development. Firstly, in infants with a defect of glandular ontogenesis (congenital hypothyroidism), the participation of maternal thyroid hormones to the fetal circulating thyroxine environment is normal and, therefore, risk of brain damage results exclusively from the insufficient hormone production by the abnormal fetal thyroid gland. Secondly, when it is only the maternal thyroid gland that is functionally deficient (autoimmune hypothyroidism), the severity and temporal occurrence of maternal underfunction will both drive the resulting consequences for impaired fetal neuronal development. Clinical situations of this type may obviously take place already during early gestation (in women with known but untreated hypothyroidism) or appear only during later gestational stages (in women who have AITD and remain euthyroid during the first half of gestation). Lastly, in conditions with iodine deficiency, both maternal and fetal thyroid functions are affected and, therefore, it is primarily the degree and precocity of the maternal hypothyroxinemia due to iodine deficiency during pregnancy that will drive the potential repercussions for fetal neurological development. In the present review, we summarize available data and develop our present concepts concerning the complex feto-maternal thyroid relationships and the potential impacts of thyroid function abnormalities on the ideal development of the offspring. 相似文献
23.
GTA Jombo EM Mbaawuaga AN Gyuse MNO Enenebeaku EE Okwori EJ Peters S Akpan F Odey EA Etukumana JT Akosu 《Asian Pacific journal of tropical medicine》2010,3(5):402-406
ObjectiveTo ascertain the socio-cultural factors influencing the rate of utilization of insecticide treated bed nets (ITNs) in a malaria endemic city of Makurdi, north central Nigeria.MethodsThe study was cross-sectional in nature using systematic sampling method to identify households. Both quantitative and qualitative data was generated from adult women using structured and semi structured questionnaires, and focused group discussions (FGDs) to obtain information on rate and patterns of utilization of ITNs. Information such as age, educational level, marital status, awareness or otherwise of the existence of malaria, and factors influencing rate of ownership and utilization of ITNs were obtained. FGDs were used to obtain qualitative information on rate of utilization of ITNs not captured in the questionnaires. Data obtained was analysed using Epi Info 6 statistical software.ResultsAmong the respondents interviewed, 97.0% (2 013/2 075) were aware of existence of malaria and 87.0% of these (1 751/2 013) would associate it with mosquitoes. The rate of ownership of any bed net, ITNs and untreated bed nets (UTNs) was 25.1%, 17.0% and 8.3%, respectively. Utilization of ITNs among children was 30.0% (112/373) and UTNs 12.9% (48/373). Positive contributors to ITNs utilization were literacy, enhanced economy, experience of marriage, and being gainfully employed (P<0.05); while negative contributors were ignorance, poverty and some cultural beliefs and values.ConclusionsA more synchronized advocacy should be carried out on the potential benefits of ITNs utilization and sustained. Also ITNs should be made available to the people of the community at minimal or no cost. 相似文献
24.
EI Ekanem TU Agan EE Efiok MI Ekott E Okodi 《Asian Pacific journal of tropical medicine》2010,3(7):567-570
ObjectiveTo assess the prevalence of anemia and asymptomatia malaria parasitemia and the effect of prior antimalarials therapy on the parasite density in pregnant women at their first antenatal visit at the secondary level health care facility in Nigeria.MethodsThis cross sectional observational study was carried out in the antenatal clinic of General Hospital, Ikot Ekpene, Akwa Ibom State, Nigeria for 3 months period (1st June to 31st August, 2009). Five hundred and fourteen women attending their first antenatal registration visits in the hospital were recruited in the study. Socio-demographic information was obtained using pre-tested questionnaires. The malaria parasite was obtained by examining thick and thin blood films prepared on 2 glass slides while the hematocrit was obtained through 2 capillary tubes read by a Hawksleys microhematocrit reader.ResultsA total of 514 pregnant women participated in the study with a mean maternal age of 21.4 years and a mean gestational age at booking of 18.3 weeks. The primigravid women booked at significantly lower gestational age than multigravidae (16.2 weeks vs 21.6 weeks). Most of the women (59.3%) were anemic, out of which 60.4% were primigravida. More than half of the women had moderate to high parasite density and only 6.8% had no malaria parasitemia. All patients with severe anemia were parasitemic. Out of the 479 (93.2%) women with parasitemia, a third had taken antimalarial drugs. A majority (60.3%) of those without prior antimalarial drugs had moderate to high density parasitemia.ConclusionsThis study shows high prevalence of anemia in women with asymptomatic malarial parasitemia, particularly the primigravida. The severity of anemia is directly related to the density of malaria parasitemia. Those with effective antimalarial therapy appear to have low density parasitemia and therefore mild anemia. Routine screening for anemia and malaria parasites at booking, prompt parasite clearance and correction of anemia would reduce the associated maternal and perinatal complications. 相似文献
25.
Peracchi M; Toschi V; Bamonti-Catena F; Lombardi L; Bareggi B; Cortelezzi A; Colombi M; Maiolo AT; Polli EE 《Blood》1987,69(6):1613-1616
To verify the clinical usefulness of extracellular cyclic nucleotide determination as a tumor marker, plasma cyclic AMP (cAMP) and cyclic GMP (cGMP) levels were measured in 70 normal subjects and 173 acute leukemia patients studied in different stages of their disease. Mean plasma cAMP levels were similar in leukemic and normal subjects, although in 48 patients in the active stage of the disease, first diagnosis, or relapse, the cAMP values were below the normal range, and most of these patients failed to respond to chemotherapy. Plasma cGMP levels were markedly elevated in untreated patients, normalized in all patients who attained complete remission, and increased promptly to pretreatment values in patients who relapsed, suggesting that their determination may be useful to monitor the patients' response to treatment. 相似文献
26.
ObjectiveTo determine the knowledge of HIV/AIDS among primary school pupils in north central area of Nigeria.Methods2000 randomly selected primary school pupils in and around eastern part of Idoma area of Benue state were interviewed using an open-ended questionnaire. Data analysis was done with EPI-INFO 2000. The Chi-square test was used for statistical analysis and the 0.05 level of significance was adopted.ResultsA totle of 1010 males and 990 females at ages between five and sixteen years were drawn from 10 primary schools in the area. Pupils in the higher classes were more knowledgeable and sex difference was not statistically significant. Certain misconceptions were noted.ConclusionsThere is need for health education for all cadres of primary school pupils in the area, which will increase the awareness of the disease. 相似文献
27.
SANMIGUEL CP HAGIIKE M MINTCHEV MP DELA CRUZ R PHILLIPS E CUNNEEN SA CONKLIN JL SOFFER EE 《Neurogastroenterology and motility》2006,18(6):484-485
Background: Electrical stimulation (ES) of the stomach has been shown to modulate LESP. Electrical stimulation, using neural high frequency stimulation (NGES) can induce contractions of the smooth muscle of the gut. The purpose of this study was to determine if electrical stimulation of the LES can affect LESP. Methods: Four female hound dogs, weight: 20–25 kg, underwent an esophagostomy that allowed the introduction of a sleeve manometry catheter into the esophagus. They were also implanted with a pair of electrodes along the longitudinal axis of the LES. After 3 weeks of recovery, they underwent esophageal manometry recording during control and ES, performed randomly on separate days, using 4 different stimulations: 1‐Low frequency: freq: 6 cycles/min, pulse: 350 milisec, amp: 5 mAmp; 2 High‐frequency: freq: 50 Hz, pulse: 1 milisec, amp: 5 mAmp; 3‐ NGES: freq: 50 Hz, pulse:20 milisec, amp:10 volts; 4‐ High‐frequency, circular: freq: 20 Hz, pulse:1 milisec, amp:5 mAmp. All recordings were performed 1 hour after consumption of 3 ounces of canned dog food, to prevent fluctuations in LESP and under mild sedation (acepromazine 0.5 mg kg1). Tests consisted, during ES days, of 3 periods of 20 minutes each: control , stimulation and post stimulation. The effect of NGES was also tested under anesthesia and following administration of L‐NAME 50 mg kg1 IV. and also atropine 0.05 mg kg1 IV. Analysis: area under the curve (AUC) and pressure were compared among the 3 periods. Data shown as mean ± SD, ANOVA and t‐test, p < 0.05. Results: Sustained increase in LESP was observed during low frequency stimulation, 32.1 ± 12.8 vs. 42.4 ± 18.0 vs. 50.1 ± 23.6, control vs. stimulation vs. post stimulation respectively, p = 0.013. AUC also significantly increased during and after stimulation, 39,320.3 ± 15,722 vs. 51,294 ± 21,826 vs. 59,823.6 ± 28,198.4 mmHgxsec, control vs. stimulation vs. post stimulation respectively, p = 0.01. There was no significant change with other types of ES. NGES induced an initial rise in LESP followed within few seconds by relaxation with slow resumption of pressure over a 1 minute period. L‐NAME increased LESP and augmented the initial rise in LESP following NGES but markedly diminished or abolished the relaxation phase. Atropine lowered LESP and abolished the initial rise in LESP induced by NGES. Conclusions: Low frequency ES of the LES increases LESP in conscious dogs. NGES has dual effect on LESP: an initial stimulation, cholinergically mediated, followed by relaxation mediated by nitric oxide. 相似文献
28.
Inhibition and potentiation of platelet function by lysolecithin 总被引:1,自引:0,他引:1
29.
30.
On the amino-acid sequence of flagellin from Bacillus subtilis 168: comparison with other bacterial flagellins 总被引:7,自引:0,他引:7 下载免费PDF全文
R J Delange J Y Chang J H Shaper R J Martinez S K Komatsu A N Glazer 《Proceedings of the National Academy of Sciences of the United States of America》1973,70(12):3428-3431
A partial amino-acid sequence of Bacillus subtilis 168 flagellin is presented. The region of unassigned sequence in this 304-residue polypeptide chain spans residues 158-173. Comparison of the 27-residue aminoterminal CNBr peptide of B. subtilis 168 flagellin with that derived from the flagellin of the serologically unrelated strain of B. subtilis, W23, shows only three conservative substitutions, whereas the 16-residue carboxyl-terminal peptides derived from these flagellins were identical. The comparison of the very limited sequence information available on the flagellins of Salmonella and Proteus with that on B. subtilis indicates homology between these proteins. 相似文献