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991.
Lalley PM 《Respiratory physiology & neurobiology》2004,139(3):71-262
In adult pentobarbital-anesthetized and unanesthetized decerebrate cats, the D(1)R agonists (6-chloro-APB, SKF-38393, dihydrexidine) given intravenously restored phrenic nerve and vagus nerve respiratory discharges and firing of bulbar post-inspiratory neurons after the discharges were abolished by the micro-opioid receptor agonist fentanyl given intravenously. Reversal of opioid-mediated discharge depression was prevented by the D(1)R antagonist SCH23390. Iontophoresis of the micro-opioid receptor agonist DAMGO depressed firing of medullary bulbospinal inspiratory neurons. Co-iontophoresis of SKF-38393 did not restore firing and had no effect on bulbospinal inspiratory neuron discharges when applied alone. The D(1)R agonists given intravenously prolonged and intensified phrenic nerve and bulbospinal inspiratory neuron discharges. They also increased reactivity to CO(2) by lowering the phrenic nerve apnea threshold and shifting the phrenic nerve-CO(2) response curve to lower et(CO(2)) levels. Intravenous fentanyl on the other hand decreased CO(2) reactivity by shifting the phrenic nerve apnea threshold and the response curve to higher et(CO(2)) levels. Fentanyl effects on reactivity were partially reversed by D(1)R agonists. 相似文献
992.
OBJECTIVE: Environmental tobacco smoke (ETS) has been associated with a number of negative health outcomes for exposed children. The goal of this study was to assess the association between ETS and dental caries in a pediatric population. METHODS: This study included 637 Iowa Fluoride Study children whose parents provided socioeconomic information, completed at least three questionnaires during the first year of life, and had a primary dentition exam at age 4-7 years. Households reporting in all questionnaires that someone smoked in the home were categorized as regularly smoking homes. Socioeconomic status (SES) was divided into three groups (low, middle, and high) based on family income and mother's education. Children were classified as having caries if any of the primary teeth had fillings or cavitated lesions at the primary dentition exam. RESULTS: Overall, children residing in regularly smoking homes had a higher prevalence of caries. For the middle SES group and overall, the children from smoking homes had a significantly higher prevalence of caries compared to nonregular/nonsmoking homes (52% vs 24%, P=.05 and 44% vs 25%, P=.002, respectively). After adjusting for age, SES, toothbrushing frequency, total ingested fluoride, and combined intake of soda pop and powdered drink beverages, the relationship of smoking and caries still remained significant (odds ratio [OR]=3.38; P=.001). CONCLUSIONS: Environmental tobacco smoke was associated with an increased risk of caries among children. 相似文献
993.
AIM: To investigate whether maternal smoking remains associated with decreased breastfeeding duration after adjustment for the mother's infant feeding intention. METHOD: Pregnant women resident within Avon, UK, expected to give birth between 1 April 1991 and 31 December 1992 were recruited in a longitudinal cohort study. Main outcome measures included maternal infant feeding intention at 32 wk of pregnancy: intention for the first week, intention for the rest of the first month and intention in months 2 to 4. Maternal smoking was defined as any smoking reported at any time during pregnancy. Data on initiation and duration of breastfeeding were based on the questionnaire at 6 mo postpartum, supplemented by data from the 15-mo questionnaire if necessary. RESULTS: Women who smoked during pregnancy had an adjusted odds ratio of 1.5 (95% CI: 1.3-1.7) of not breastfeeding at 6 mo compared to non-smokers (adjusting for maternal age, education and intention). Survival analysis of duration of breastfeeding in the first 6 mo postpartum found that women who intended to breastfeed for less than 1 mo were 78% more likely to stop at any given time than women planning to breastfeed for at least 4 mo, while smokers were 17% more likely to stop breastfeeding than non-smokers. CONCLUSION: Although women who smoke are less likely to breastfeed their infants than are non-smoking women, it appears that this is largely due to lower motivation to breastfeed rather than a physiological effect of smoking on their milk supply. 相似文献
994.
Christina Vogt?IsaksenEmail author Rigmor?Austgulen Lisa?Chedwick Pal?Romundstad Lars?Vatten Catherine?Craven? 《Pediatric and developmental pathology》2004,7(5):433-442
Pregnant
women who smoke are at greater risk of delivering a growth-restricted infant
than nonsmoking mothers. We wanted to see if apoptosis could be involved in the
mechanisms behind smoke-induced growth restriction, and our aim was to compare
apoptosis in the placenta of smoking mothers giving birth to growth-restricted
infants and nonsmoking mothers with infants of appropriate weight. The project
was conducted at the Magee—Womens Hospital and Magee—Womens
Research Institute, University of Pittsburgh, PA. Histological sections from 20
placentas were selected from smoking mothers who had given birth to
small-for-gestational-age infants (birth weight 2 SD). The controls
were gestational-age matched nonsmoking mothers with infants having
appropriate-for-gestational-age weight. The TUNEL method was used to
demonstrate DNA fragmentation in nuclei, and a monoclonal antibody M30,
specific for a neo-epitope on cytokeratin 18, was used to identify apoptotic
epithelial cells. The positive nuclei (TUNEL) and positive cells (M30-positive
cytoplasm) were counted blindly both in villous tissue and in decidual/basal
plate tissue. M30-positive cells in villous tissues were significantly
increased in placentas from smoking mothers compared to nonsmoking mothers.
When evaluated by the TUNEL method, the difference between the two groups of
women was not significant. Our study shows that apoptosis was increased in the
placentas of smoking mothers with growth-restricted infants. The difference
between the two groups was mainly in the syncytiotrophoblast layer and in
connection with perivillous fibrin deposition. Cigarette smoke with reduction
in blood flow has previously been shown to increase apoptosis, and it is
possible that this could be one of the mechanisms playing a role in the growth
restriction.The work was performed at Magee—Womens Hospital and
Magee—Womens Institute, University of Pittsburgh, Pittsburgh, PA, USA.
1;
Deceased April 1, 2003, former address: Valley View Medical Center, 595 South
75 East, Cedar City, UT 84720, USA. 相似文献
995.
Núñez JT Delgado M Girón H Pino G 《The Australian & New Zealand journal of obstetrics & gynaecology》2004,44(3):239-243
OBJECTIVE: To examine risk factors for preinvasive and invasive lesions of the cervix in Venezuelan female sex workers (FSW). METHODS: A total of 438 FSW were analysed. Each FSW had their clinical history recorded, a gynaecological examination, a Pap smear and a colposcopic examination of the cervix. A cervical biopsy was taken under colposcopic guidance when there was an abnormal epithelium. The statistical methods used were Student's t-test, chi(2) test and logistic regression. RESULTS: The sex workers' mean age was 32.1 +/- 7.9 years old (mean +/- standard deviation). The age of the first sexual intercourse activity for the FSW was 15.9 +/- 2.1 years. Sixty-four of the 84 women (76.2%) who had cervical biopsies had preinvasive and invasive lesions; 41 (9.4%) had cervical intra-epithelial neoplasia (CIN) 1, 12 (2.7%) had CIN 2, eight (1.8%) had CIN 3, two (0.5%) had microinvasive carcinoma, and one (0.2%) had invasive carcinoma. Forty of these 64 women (62.5%) with preinvasive or invasive lesions had a concurrent histological diagnosis of human papilloma virus (HPV) infection (P < 0.0001). The FSW with cervical pathology were younger (P < 0.05) and had their first sexual intercourse earlier (P < 0.02) than FSW with no pathology. Two hundred and seventy-six (63%) of the FSW were current smokers, and 47 of these women (17.6%) had cervical pathology (P < 0.03). CONCLUSIONS: First sexual experience before 20 years of age, cigarette smoking and HPV infection were high-risk factors for preinvasive and invasive lesions of the cervix in Venezuelan FSW. 相似文献
996.
There is a lack of evidence on the prevalence of smoking among mental health nurses, and the beliefs and attitudes they hold about smoking at work. This paper describes results from a cross-sectional survey of clinical staff working in a UK specialist charitable-status psychiatric hospital and focuses on the responses of registered mental health nurses. Questionnaires specifically developed for this study were sent to all 1371 clinical employees. Completed questionnaires were returned by 167 of 429 (38.9%) registered nurses (RNs), 300 of 842 (35.6%) nursing assistants (NAs), and 123 of 200 (61.5%) other health professionals (OHPs). Twenty-nine (17.4%) RNs, 93 (31%) NAs and eight (6.5%) OHPs reported themselves as current smokers. Differences in response to attitudinal questions between groups could not be attributed to age. RN smokers were significantly more likely than RN non-smokers to state that staff should be allowed to smoke with patients, and to report therapeutic value for patients in this activity. RN smokers were less likely than RN non-smokers to report that patients should be encouraged to stop smoking. RNs were significantly more likely than OHPs to report therapeutic value for patients in smoking with staff, even after controlling for the possible confounding effect of smoking status. Implications of the survey are discussed in the context of the international literature, including the disproportionately high smoking prevalence among patients living in psychiatric institutions and current guidelines to move towards no 'smoking allowed' areas for staff working in them. 相似文献
997.
Brandstätter A Peterson CT Irwin JA Mpoke S Koech DK Parson W Parsons TJ 《International journal of legal medicine》2004,118(5):294-306
Large forensic mtDNA databases which adhere to strict guidelines for generation and maintenance, are not available for many populations outside of the United States and western Europe. We have established a high quality mtDNA control region sequence database for urban Nairobi as both a reference database for forensic investigations, and as a tool to examine the genetic variation of Kenyan sequences in the context of known African variation. The Nairobi sequences exhibited high variation and a low random match probability, indicating utility for forensic testing. Haplogroup identification and frequencies were compared with those reported from other published studies on African, or African-origin populations from Mozambique, Sierra Leone, and the United States, and suggest significant differences in the mtDNA compositions of the various populations. The quality of the sequence data in our study was investigated and supported using phylogenetic measures. Our data demonstrate the diversity and distinctiveness of African populations, and underline the importance of establishing additional forensic mtDNA databases of indigenous African populations. 相似文献
998.
Seasonality in human semen quality of smokers and non-smokers: effect of temperature 总被引:2,自引:0,他引:2
Aim: To analyse the possible effect of seasonal variation on semen parameters. Methods: The participants consisted of 1688 men attending the andrology laboratory between 1991 and 1997 for reduced fertility in the couple. Semen analysis was performed according to the WHO manual. The 84 individual months of the study period were each assigned to one of the three groups according to the average monthly outside temperature; Group A (temperature <4.4℃), Group B (4.4℃-13.3℃) and Group C (>13.3℃). Results: When comparing the different sperm parameters, the morphology was significantly better in Group C. However, when the smokers were analysed separately, this difference disappeared and significant seasonal variations were found in sperm density, total sperm count, motility and total motile sperm; they were deteriorated in the warmer season. In non-smokers, no such negative effect of increased temperature was observed. Conclusion: Sperm quality is influenced by seasonal factors. Increased environmental tempe 相似文献
999.
BACKGROUND AND AIMS: Long-term smoking increases the risk of renal diseases and it also causes the progression of the diseases. The aim of this study was to evaluate the effects of smoking on glomeruli in healthy rats exposed to long-term passive smoking for a short period of time after birth. METHODS: Sixty-five rats were randomly assigned into four groups. Groups 1 (18 males) and 2 (18 females) were exposed to smoke, whereas groups 3 (15 males) and 4 (14 females) were not exposed to smoke. Overall, 130 renal units were evaluated, and diameters of 10 different glomeruli were measured. The renal and bodyweights of the rats were measured. RESULTS: The diameter of the glomeruli was 95.51 +/- 9.25 and 100.91 +/- 4.06 microm in groups 1 and 3, respectively (P < 0.05). It was 97.32 +/- 4.06 and 98.86 +/- 6.25 microm in groups 2 and 4, respectively (P > 0.05). Irrespective of the sex, the diameter of the glomeruli was 96.42 +/- 7.15 microm in smokers and 99.92 +/- 5.56 microm in non-smokers (P < 0.05). The renal weights of the male rats affected by smoke were significantly lower than that of those that were not affected by smoke (P < 0.05). Bodyweights of male rats affected by smoke were significantly lower that of those not affected (P < 0.05). There was a weak correlation between the diameter of the glomeruli and the bodyweights of male rats affected by smoke (r = 0.474, P < 0.05). CONCLUSION: We conclude that passive smoking might have a negative affect on renal morphometry and body growth. 相似文献
1000.
Raherison C Nejjari C Marty ML Filleul L Barberger-Gateau P Dartigues JF Tessier JF 《Allergy》2004,59(9):940-945
BACKGROUND: In the last decades in industrialized countries, the increase of life expectancy has resulted in an increase in the population of the elderly. However, little is known about the prevalence of allergies in the elderly population. The aim of the study was to investigate the specific relationship of serum IgE and Phadiatop, with asthma, rhinitis, and smoking in a sample of an elderly population. METHODS: Subjects from the Paquid cohort living in Gironde Department (age 65 years and over) in France were followed up since 1988 (PAQUID cohort). RESULTS: Among the randomized sample of 352 subjects, there were 158 men (45%) and 194 women (55%). The lowest levels of IgE were in subjects with chronic sputum; and in normal subjects (47.1 +/- 56.4 vs 56.2 +/- 73.9, NS). Multiple linear regression was performed with log(10) IgE values as a dependent variable and age, Phadiatop test, smoking, and respiratory symptoms independently in men and in women. In men, a significant relationship was observed between IgE values and Phadiatop test (P < 0.001), asthma history (P = 0.002), and smoking (P = 0.019). CONCLUSIONS: Respiratory allergy is present in persons >65 years of age. There is an association between smoking and IgE level independent of allergic reactivity to common allergens in the elderly. 相似文献