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21.
Abstract Maxillary and mandibular anterior permanent teeth in 38 children aged 7–12 years were examined 2 × with an interval of 2 years to determine whether spontaneous facial/lingual tooth position changes were related to alterations of the widths of keratinized and attached gingiva and the clinical crown height. Measurements included dental plaque, gingival inflammation, probing depth, and width of keratinized and attached gingiva. In addition, study casts from the baseline and 2-year examinations were used to measure clinical crown height and tooth position. The results showed that significant alterations in the widths of the keratinized and attached gingiva took place when the teeth changed positions in facial or lingual directions. The changes in gingival widths could to some extent be coupled to changes in clinical crown height. In teeth moving lingually, the gingival widths increased and the clinical crown height decreased. In teeth moving facially, the gingival widths decreased, and the facial gingiva sometimes receded. These gingival alterations call for examination of the facial gingiva as part of the monitoring of the development of the permanent dentition. 相似文献
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The buffering capacity of tears collected from contact lens wearers was compared to that from non-contact lens wearers. Three groups of subjects were investigated: 6 subjects not wearing contact lenses, 3 subjects wearing rigid contact lenses, and 3 subjects wearing hydrogel contact lenses. Each of the 12 subjects provided, on 6 separate occasions, 100 microliters of tears. The pH of the tears was measured with a closed chamber, temperature stabilized micro-electrode system firstly on collection and then after titration with acid and base. In all, 28 titration steps across the acid-base spectrum were completed for each subject's tears on each occasion. These tear pH responses to acid-base challenge were compared to that of unbuffered distilled water for the same titration procedure. There was no statistically significant effect of contact lens wear on tear buffering capacity, but considerable inter-subject variability was noted. 相似文献
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25.
To assess the potential influence of diet and endogenous peptide anabolic hormone secretion on exercise-related differences in body composition, we compared levels of macronutrient intake, insulinlike growth factor I (IGF-I), and fat-free mass (FFM) and fat mass (FM) in matched groups of exercising women with and without secondary hypothalamic amenorrhea. Women were tightly matched according to somatotype and grouped into those with exercise amenorrhea (EXam, n = 6), exercise eumennorhea (EXeu, n = 5), and sedentary eumennorheic controls (SED, n = 5). Although no between-group difference was observed in FFM, the EXeu subjects had a significantly lower fat fraction and a significantly elevated FFM/FM ratio. Kilocaloric and protein intakes did not differ between groups, but dietary fat intake was lowest and carbohydrate intake highest in the EXam subjects. Dietary macronutrients were not correlated with the FFM/FM ratio. However, levels of insulinlike growth factor I were significantly correlated to the FFM/FM ratio and there was a clear trend for the hormone to be highest in the EXeu subjects. We conclude that differences in body composition between exercising women with and without exercise-induced hypothalamic-pituitary dysfunction were related to an alteration in IGF-I secretion, although differences in macronutrient intake might also be a factor. Further studies are warranted to elaborate upon the dietary and hormonal factors regulating the body composition response to exercise. 相似文献
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27.
Anna B?ogowska Izabella Rzepka-Górska S?awomir Zó?towski 《Gynecological endocrinology》2005,20(5):270-273
OBJECTIVE: Constitutional delay of puberty (CDP) is the absence of secondary sexual features in otherwise healthy girls past the 13th year of life. The aim of the present work was to follow the development of estrogen-dependent sexual features, determine the concentrations of gonadotropins, estradiol and sex hormone-binding globulin (SHBG) in girls with CDP at menarche and compare the findings with normal controls. METHODS: We enrolled 11 girls with CDP and 40 controls. Primary, secondary and tertiary sexual features were studied at menarche +/- 3 months. The size of the ovaries and uterus was measured using transabdominal ultrasound. Maturation of breasts and pubic hair was staged according to Tanner. Concentrations of gonadotropins (follicle-stimulating hormone (FSH), luteinizing hormone) and estradiol were measured with immunoenzymatic methods. For measurement of SHBG, a radioimmunoassay was applied. RESULTS: Menarche in CDP girls usually appeared with Stage IV or V of breast development and Stage IV of pubic hair development according to Tanner. CDP girls demonstrated a significantly smaller volume of the uterine body at menarche compared with controls (p = 0.0004). Significantly lower levels of FSH (p = 0.0363) and estradiol (p = 0.0332), as well as a tendency towards lower levels of SHBG, were revealed in CDP girls at menarche. CONCLUSION: In CDP girls, menarche is accompanied by more mature tertiary sexual features, apparently resulting from longer exposure of estrogen-dependent tissues to the action of bioactive endogenous estrogens. The smaller volume of the uterine body in CDP girls at menarche may be attributed to decreased concentrations of FSH and estradiol, as well as to the possibility of decreased insulin-like growth factor-1 and increased neuropeptide Y levels. 相似文献
28.
Regulation of G proteins by chronic antidepressant drug treatment in rat brain: tricyclics but not clorgyline increase Go alpha subunits. 总被引:4,自引:0,他引:4
K P Lesch C S Aulakh T J Tolliver J L Hill D L Murphy 《European journal of pharmacology》1991,207(4):361-364
The effect of long-term (3-week) administration of various antidepressant drugs on the steady-state concentrations of G protein alpha subunits, Gs alpha, Gi alpha, and Go alpha, has been investigated in rat brain using an enzyme-linked immunosorbent assay. Tricyclic antidepressants and clorgyline decreased Gs alpha and, to a lesser extent, Gi alpha in several brain regions, while Go alpha was increased by tricyclics but not clorgyline. We conclude that long-term treatment with antidepressant drugs exerts differential effects on G protein alpha subunits, and that antidepressant efficacy may potentially be based on functional modifications of signal transduction. 相似文献
29.
Liesbeth Vandenput Fernand Labrie Dan Mellstr?m Charlotte Swanson Thomas Knutsson Ralph Peeker Osten Ljunggren Eric Orwoll Anna L Eriksson Jan-Erik Damber Claes Ohlsson 《Journal of bone and mineral research》2007,22(2):220-227
Androgens are important regulators of bone and prostate health in elderly men. The role of serum levels of glucuronidated androgen metabolites as predictors of BMD and prostate volume in men is unclear. We show that specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men. INTRODUCTION: Androgens are important regulators of bone and prostate health in elderly men. Local synthesis and degradation of androgens are likely to be important parameters of biological action of androgens in androgen-responsive tissues. The aim of this study was to determine the role of serum levels of glucuronidated androgen metabolites as predictors of BMD and prostate volume in elderly men. MATERIALS AND METHODS: A subsample of the population-based Swedish part of the MrOS study (n = 631, average age = 75.9 years) was investigated. Bone parameters were measured using DXA. Serum levels of total testosterone (T) and dihydrotestosterone (DHT) were measured by gas chromatography/mass spectroscopy (GC-MS); androstane-3alpha,17beta-diol-3glucuronide (3G) and androstane-3alpha,17beta-diol-17glucuronide (17G) were measured by liquid chromatography/mass spectroscopy. Prostate volume (n = 159) was measured by transrectal ultrasound. RESULTS: The general pattern is that two of the glucuronidated androgen metabolites, namely 17G and 3G, are stronger positive predictors of BMD than the bioactive androgens (T and DHT). In addition, 17G is a clear positive predictor of prostate volume, explaining 4.5% of the variance in prostate volume, whereas the bioactive androgens do not display any association with prostate volume. CONCLUSIONS: Serum levels of specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men. Future studies should determine if the glucuronidated androgen metabolites also reflect other biological correlates of androgenic activity, including prostate cancer, and if low levels might be a marker of general androgen deficiency in men. 相似文献
30.
Sheetal Chopra Anna S Lev-Toaff Fatih Ors Diane Bergin 《Journal of ultrasound in medicine》2006,25(5):617-27; quiz 629
OBJECTIVE: The purpose of this presentation is to show the imaging findings of the common and uncommon variants of adenomyosis as seen on sonography and magnetic resonance imaging (MRI). METHODS: A 3-year database search was performed to identify women who had pelvic sonography and pelvic MRI within a 6-month interval. Images of these cases were retrospectively reviewed. RESULTS: Eighty women were identified. Adenomyosis was diagnosed on MRI, which was used as the reference standard, in 45 of these women. The correct diagnosis was made on sonography in 73% of the cases. CONCLUSIONS: Awareness of the spectrum of imaging features of adenomyosis is important to use sonography effectively for diagnosing this entity and to help avoid misdiagnosis. 相似文献