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61.
A high-speed imaging technique was used to investigate the effects of inhibitors and activators of protein kinase C (PKC) on the [Ca2+]i transients and contraction of fura-2 loaded rat ventricular cardiac myocytes. The amplitude of the [Ca2+]i transient was reduced following treatment with 100 nM phorbol 12,13-dibutyrate (PDBu), whereas the PKC inhibitors staurosporine (0.5 microM) and calphostin C (10 microM) increased [Ca2+]i transient amplitude, elevated basal [Ca2+]i and slowed the decay of the [Ca2+]i transient. These changes were paralleled by similar alterations in the rate and extent of cell shortening. The activity of nitrendipine-sensitive Ca2+ channels was monitored indirectly as the rate of Mn2+ quench of cytosolic fura-2 in electrically-paced cells. PDBu reduced Mn2+ influx by six-fold, whereas staurosporine and calphostin C increased the influx rate by eight-fold and seven-fold over basal quench, respectively. The caffeine releasable Ca2+ pool was reduced in the presence of PDBu and increased transiently in presence of staurosporine. The effects of PKC activation and inhibition on sarcoplasmic reticulum Ca2+ content may be secondary to alterations of sarcolemmal Ca2+ influx. However, the PKC inhibitors also decreased the rate of sarcoplasmic reticulum Ca2+ uptake in permeabilized myocytes, suggesting that a direct effect of PKC on the sarcoplasmic reticulum may contribute to the prolongation of the [Ca2+]i transient under these conditions. The present work demonstrates that basal PKC activity has a potent depressant effect, mediated primarily through inhibition of sarcolemmal Ca2+ influx, which may play a key role in setting the basal tone of cardiac muscle. 相似文献
62.
Vulvovaginal candidiasis is a frequent inflammatory process in women but it has not been widely studied in female sex workers (FSWs). To estimate the frequency of Candida species infection in FSWs and to identify related risk factors and clinical findings, we carried out a retrospective study of 1923 FSWs over 11 years. We also performed a prospective study of 163 consecutive FSWs with a history of candidiasis during a 4-year period. Candida species were isolated in 1967 samples (18.5% of the total). Candida albicans (89.3%) was the most frequent species, followed by Candida glabrata (2.7%), Candida parapsilosis (1.2%) and Saccharomyces cerevisiae (0.4%). In the prospective study of 163 patients, we found vaginal discharge in 76.1% of cases, soreness in 52.1% and vulval pruritus in 32.5%. We identified 12 patients (7.4%) with recurrent vulvovaginal candidiasis. No statistical difference was found between recurrent vulvovaginitis and the use of oral contraceptives, oral sex, tight-fitting clothing and synthetic underwear. FSWs have the same prevalence of candidiasis as other groups of women described in published literature. The proportion of albicans and non-albicans species does not differ between women with recurrent and non-recurrent vulvovaginal candidiasis (VVC). 相似文献
63.
LB Bunyard LI Katzel MJ Busby-Whitehead Z Wu AP Goldberg 《Canadian Metallurgical Quarterly》1998,68(5):1136-1142
BACKGROUND: Energy requirements for weight maintenance decrease with age. Often, this decline is not proportionately matched by reduced energy intake, resulting in weight gain. OBJECTIVE: We hypothesized that energy requirements for total daily weight maintenance in healthy, sedentary, middle-aged men would increase after regular aerobic exercise or aerobic exercise plus weight loss to levels comparable with those in middle-aged athletes. DESIGN: Weight-maintenance energy requirements were determined during weight stability (+/- 0.25 kg) in 14 lean, sedentary (LS) men; 18 obese, sedentary (OS) men; and 10 male athletes of comparable ages (x +/- SEM: 58 +/- 1 y). Studies were done at baseline and after 6 mo of aerobic exercise (LS men) or aerobic exercise plus weight loss (OS men) or 3 mo of deconditioning (athletes). RESULTS: The interventions raised maximal oxygen uptake (VO2max) by 15% in the LS men and by 13% in the OS men and decreased it by 14% in athletes (all P < 0.01), eliminating the differences among groups at baseline. Body fat was reduced significantly in LS and OS men; fat-free mass decreased in OS men. Average daily energy requirements increased by 8% in LS men and by 5% in OS men (both P < 0.01) to levels comparable with the baseline requirements of athletes and correlated with VO2max (r2 = 0.22, P < 0.0001) and fat-free mass (r2 = 0.05, P < 0.02) across the range of VO2max achieved by all subjects. CONCLUSIONS: Under free-living conditions, aerobic exercise eliminated the difference in weight-maintenance energy requirements between middle-aged sedentary and athletic men, suggesting that energy requirements of healthy, middle-aged men are modifiable by regular physical activity. 相似文献
64.
L Haataja J Schleutker AP Laine M Renlund ML Savontaus C Dib J Weissenbach L Peltonen P Aula 《Canadian Metallurgical Quarterly》1994,54(6):1042-1049
Salla disease (SD), or adult-type free sialic acid storage disease, is an autosomal recessive lysosomal storage disorder characterized by impaired transport of free sialic acid across the lysosomal membrane and severe psychomotor retardation. Random linkage analysis of a sample of 27 Finnish families allowed us to localize the SD locus to the long arm of chromosome 6. The highest lod score of 8.95 was obtained with a microsatellite marker of locus D6S286 at theta = .00. Evidence for linkage disequilibrium was observed between the SD locus and the alleles of three closely linked markers, suggesting that the length of the critical region for the SD locus is in the order of 190 kb. 相似文献
65.
This article discusses the shift of emphasis in implantology from the phenomenon of osseointegration of implants to the accurate fabrication of the prosthesis, recognizing the implant/prosthesis unit as an actual replica rather than a replacement of the missing tooth. The study of kinetics with its succession of mandibular cycles is used to discuss the integration of mastication and occlusion. The importance of periimplant ligament in natural teeth is discussed, along with the impact of its absence on implant mobility. The impact of the bone types and the root surface architecture on the implant-bearing surface is presented along with the stress of the mastication forces. All these factors have to be considered in the treatment planning and effectively communicated to the laboratory. The learning objective of this article is to provide updated information in those areas for the reader. 相似文献
66.
AP Colombo D Sakellari AD Haffajee A Tanner MA Cugini SS Socransky 《Canadian Metallurgical Quarterly》1998,25(7):596-604
The purpose of this investigation was to compare the levels of serum IgG antibody to 85 subgingival species in 32 refractory periodontitis, 56 successfully treated, and 33 periodontally healthy subjects. Refractory subjects showed mean full mouth attachment loss and/or >3 sites showing attachment loss >2.5 mm within 1 year after 2 treatment modalities, scaling and root planing and surgery plus systemically administered tetracycline. Successfully-treated subjects showed mean attachment level gain and no sites with attachment loss >2.5 mm, 1 year post-therapy. Periodontally healthy subjects exhibited no pocket or attachment level >3 mm, and no evidence of progressing attachment loss during 1 year of monitoring. Baseline serum was obtained from each subject and tested against 85 subgingival species, including reference strains and strains isolated from refractory subjects, using checkerboard immunoblotting. Significance of differences in levels of serum antibody among groups were sought using the Kruskal-Wallis test. Refractory subjects constituted a heterogeneous group based on their serum antibody response to subgingival species. Some individuals had antibody reactions to many subgingival species, while other subjects showed fewer or low numbers of responses. On average, refractory subjects exhibited higher numbers and levels of serum antibody reactions to a wide range of subgingival species than successfully treated or periodontally healthy subjects. Differences in serum antibody among clinical groups were more striking at higher threshold levels of antibody (>50 microg/ml and > 100 microg/ml). The data showed that a subject was 10.1 x more likely to be refractory if the subject exhibited antibody reactions with >9 subgingival species at >50 microg/ml (p<0.001, after adjusting for multiple comparisons). Serum antibody to a subset of the test species differed among the clinical groups. Porphyromonas gingivalis, Bacteroidesforsythus, and some strains isolated from refractory subjects (a novel Neisseria sp., Enterococcus faecalis, Prevotella loescheii and Prevotella oulora) elicited high serum antibody in the successfully treated and refractory subjects. High levels of serum antibody to a Microbacterium lacticum-like organism, Streptococcus oralis, Streptococcus constellatus, Actinobacillus actinonmycetemcomitans serotype c and Haemophilus aphrophilus significantly increased the likelihood of a subject being refractory to conventional periodontal therapy. 相似文献
67.
AP Sinha 《Canadian Metallurgical Quarterly》1977,64(7):499-500
Seven hundred and thirty-two cases of appendicectomy performed over a period of 5 years are reviewed to compare the incidence of complications and the length of the postoperative stay in hospital, depending on whether the appendix stump was simply ligated or was invaginated by purse string suture following ligation. No detrimental effects are noted following simple ligation, whereas patients who had stump invagination remained in hospital on average more than a day longer, mainly owing to a higher incidence of wound infection (16 per cent as against 6 per cent). 相似文献
68.
69.
70.
AP Mowat P Gutjahr B Portmann JL Dawson R Williams 《Canadian Metallurgical Quarterly》1976,17(7):492-494
Focal nodular hyperplasia of the liver in a 3 year old child has been successfully treated by ligation of the hepatic artery branches supplying the lesion. The prominence of the abnormal vasculature in the lesion and its possible aetiological involvement is stressed. Because of the risks of partial hepatectomy, hepatic artery ligation is suggested as the treatment of choice for focal nodular hyperplasia. 相似文献