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991.
SM Stick PR Burton L Gurrin PD Sly PN LeSou?f 《Canadian Metallurgical Quarterly》1996,348(9034):1060-1064
INTRODUCTION: Infants of mothers who smoke have reduced respiratory function and are more likely to develop wheezing. Little evidence is available on the effect of in-utero cigarette-smoke exposure as opposed to postnatal exposure to environmental tobacco smoke. We used a previously validated non-invasive method to measure the time to peak tidal expiratory flow (tPTEF) as a proportion of expiratory time (tE) in newborn infants soon after birth to examine the effects of a family history of asthma and in-utero cigarette-smoke exposure on the infants' respiratory function. METHODS: We collected respiratory-function data from 500 healthy infants of mothers taking part in the Western Australia Pregnancy Cohort Study. During behaviourally defined quiet sleep, measurements were obtained a median of 58 h (range 26-159) after the infants were born. We used uncalibrated inductance plethysmography. The uncalibrated volume signal was differentiated to flow and used to calculate respiratory rate, total inspiratory time, tE, and tPTEF. Mothers answered questionnaires on demographic, medical, and pregnancy characteristics, including smoking history. Serum cotinine measurements were available to validate self-reported smoking history in a subset of mothers (238). RESULTS: Data suitable for analysis were obtained from 461 infants. In multivariate regression analysis, lower values of tPTEF/tE were independently associated with respiratory rate (beta coefficient per 10 breaths/min 0.018 [SE 0.005], p < 0.01), age (beta coefficient per 10 h -0.008 [0.003], p < 0.01), maternal smoking during pregnancy (> 10 cigarettes daily; beta coefficient -0.049 [0.022], p < 0.05), maternal hypertension during pregnancy (-0.037 [0.015], p < 0.02), and a family history of asthma (-0.028[0.014], p < 0.05). CONCLUSIONS: In-utero smoke exposure, a family history of asthma, and maternal hypertension during pregnancy are associated with reduced respiratory function after birth. We speculate that these factors adversely affect lung development in utero. 相似文献
992.
993.
The suprachiasmatic nuclei (SCN) contain a circadian clock whose activity can be recorded in vitro for several days. This clock can be reset by the application of neuropeptide Y. In this study, we focused on determination of the receptor responsible for neuropeptide Y phase shifts of the hamster circadian clock in vitro. Coronal hypothalamic slices containing the SCN were prepared from Syrian hamsters housed under a 14 h:10 h light:dark cycle. Tissue was bathed in artificial cerebrospinal fluid (ACSF), and the firing rates of individual cells were sampled throughout a 12 h period. Control slices received either no application or application of 200 nl ACSF to the SCN at zeitgeber time 6 (ZT6; ZT12 was defined as the time of lights off). Application of 200 ng/200 nl of neuropeptide Y at ZT6 resulted in a phase advance of 3.4 h. Application of the Y2 receptor agonist, neuropeptide Y (3-36), induced a similar phase advance in the rhythm, while the Y1 receptor agonist, [Leu31, Pro34]-neuropeptide Y had no effect. Pancreatic polypeptide (rat or avian) also had no measurable phase-shifting effect. Neuropeptide Y applied at ZT20 or 22 had no detectable phase-shifting effect. These results suggest that the phase-shifting effects of neuropeptide Y are mediated through a Y2 receptor, similar to results found in vivo. 相似文献
994.
SM Marcovina JJ Albers E Wijsman Z Zhang NH Chapman H Kennedy 《Canadian Metallurgical Quarterly》1996,37(12):2569-2585
Lp[a] concentrations in nmol/L and apo[a] size isoforms, expressed in terms of the relative number of apo[a] kringle 4 (K4) repeats, were determined in 3959 whites and blacks from four U.S. communities. Plasma Lp[a] analyses were performed by an ELISA method insensitive to apo[a] size heterogeneity and apo[a] size isoforms were determined by high resolution agarose gel electrophoresis. Allele frequencies were estimated by maximum likelihood methods in order to account for the presence of null alleles and coalescence of hands on gels. The apo[a] allele frequencies and phenotype distributions differed significantly between blacks and whites (P < 0.0001). Blacks had a higher relative frequency of the intermediate alleles K4(22) through K4(28) whereas whites had a higher relative frequency of the small alleles K4(17) through K4(24) and large alleles K4(29) through K4(33). The estimated frequency of the null allele was low in both blacks (1.0%) and whites (6.7%). The Lp[a] distribution was less skewed and Lp[a] concentrations were higher in blacks than whites (mean 94 nmol/L and 48 nmol/L, median 74 nmol/L and 20 nmol/L for blacks and whites, respectively). The relationship between apo[a] size and Lp[a] concentration also differed significantly between these two racial groups. For the large polymorphs (> 31 K4 repeats) both blacks and whites exhibited uniformly low Lp[a] values. For the intermediate isoforms K4(20) through K4(30), a considerable range of Lp[a] values was evident in blacks; the median Lp[a] for each isoform increased nearly linearly as the apo[a] size decreased. In contrast in whites there was little change in median Lp[a] concentrations for isoforms K4(20) through K4(30). For the small apo[a] size (< 20 K4) both blacks and whites exhibited high median Lp[a] levels and a wide variation of Lp[a] levels. The major difference in Lp[a] levels between the two racial groups occurred in the intermediate size isoform range of K4(20) through K4(25). In conclusion, whites and blacks differ significantly in Lp[a] concentrations, allele and phenotype frequencies, and in the relationship between apo[a] size isoform and Lp[a] concentration. 相似文献
995.
996.
Giant cell tumor is a locally aggressive tumor with a high recurrence rate if not completely excised. The condition is more common among Asians than whites. During a 10-year period 44 patients, ranging in age from 12 to 51 years, were treated. The most common sites were the proximal femur and the distal radius. The aim of treatment was to excise the tumor completely. Because the tumor usually occurred at the juxtaarticular region of the bone, difficult reconstruction was expected. The authors' method of choice for filling large defects resulting from resection was to use a large vascularized bone graft from the iliac crest to enhance bone to bone corporation. The recurrence rate was low (4.5%), with only 2 recurrences: 1 at the proximal femur and the other at the proximal tibia. The functional results were highly satisfactory, with excellent stability of the joint, although in the case of the distal radius there was some degree of subluxation of the wrist joint. By applying microsurgical technique for the reconstruction, one was able to be more aggressive with excision of this locally aggressive tumor while maintaining excellent functional results. In the case of the knee, as long as 1 tibial condyle was intact, reconstruction of the other condyle using a vascularized iliac crest block maintained the joint integrity perfectly or created a pseudojoint component that was perfectly stable. 相似文献
997.
The purpose of the present investigation was to evaluate the influence on sampling repetition of aspartate aminotransferase (AST) level with 10-minute intervals. Tests based on the composition of gingival crevicular fluid (GCF) for detection of active periodontitis and GCF require the repetition of sampling. Two 30-second samples of GCF were harvested with 10-minute intervals from 123 sites in 10 healthy subjects and 20 periodontitis patients. AST activity of the first samples in periodontitis subjects were approximately 7.8% greater than that of the second samples. The difference were not significant (P > 0.05). But in healthy subjects the difference were significant (P < 0.05). AST activity correlation positively with bleeding index (BI) and probing pocket depth (PD). 相似文献
998.
M Zhong J Zhou SM Lunte G Zhao DM Giolando JR Kirchhoff 《Canadian Metallurgical Quarterly》1996,68(1):203-207
OBJECTIVE: The aims of the study were to establish the usefulness of color Doppler sonography in assessing changes in thyroid blood flow during the course of Graves' disease and to investigate which of several variables (thyroid volume, number of intraparenchymal vessels, and blood flow in the thyroid artery) were best related to thyroid hyperfunction and therefore could be used to evaluate the course of the disease. SUBJECTS AND METHODS: Fifty-six patients with Graves' disease were selected and divided on the basis of clinical and laboratory data into four groups: patients untreated at first diagnosis, patients undergoing antithyroid drug treatment, patients in remission after withdrawal of therapy, and patients having a relapse of hyperthyroidism. Ten healthy subjects served as controls. RESULTS: Patients with active hyperthyroidism (at first diagnosis, during treatment, or at relapse) had a significantly enlarged thyroid (p = .005); intrathyroid vascularization, evaluated as number of vessels per square centimeter (p < .0001); and blood flow in the thyroid artery (p < .0001) compared with control subjects and with patients in remission after withdrawal of therapy. During treatment, sonographic values were slightly lower but not significantly different from those registered in patients at the onset of hyperthyroidism, indicating that normalization of vascularity does not parallel the drug-induced decrease of hormonal synthesis. Among 21 patients in remission, the nine patients who had a relapse shortly after the examination had a higher number of vessels per square centimeter (2.18 +/- 0.34 versus 1.03 +/- 0.16, p = .03) and higher flow in the thyroid artery (80.3 +/- 19.1 versus 10.6 +/- 2.3 ml/min, p = .01) than did the other 12 patients who remained in stable remission, despite normal hormonal levels in both groups. CONCLUSION: Our results suggest that color Doppler sonography can be used to assess activity of Graves' disease and to predict the outcome of the disease after withdrawal of medical therapy. 相似文献
999.
SM Davies S Khan JE Wagner DC Arthur AD Auerbach NK Ramsay DJ Weisdorf 《Canadian Metallurgical Quarterly》1996,17(1):43-47
This paper describes the approach taken at the University of Queensland to broaden the scope of curriculum design to involve rural general practitioners, medical students and rural health care consumers. A form of nominal group process in serial telephone teleconferences was used, with a group of rural general practitioners, to develop and pilot curriculum content, learning strategies and assessment methods. Medical students assisted in the evaluation of the curriculum and representatives of rural organisations were consulted about the value of hosting medical students in rural communities. The three groups made significant contributions to the project. The results will be trialed for the entire year 6 cohort (240 students) in 1995 and will form the basis of the planned rural practice term in the new graduate course. 相似文献
1000.
R Krücken G Hackman MA Deleplanque RV Janssens IY Lee D Ackermann I Ahmad H Amro S Asztalos DJ Blumenthal MP Carpenter RM Clark RM Diamond P Fallon SM Fischer B Herskind TL Khoo T Lauritsen AO Macchiavelli RW MacLeod D Nisius GJ Schmid FS Stephens K Vetter 《Canadian Metallurgical Quarterly》1996,54(5):R2109-R2113