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《Plains anthropologist》2013,58(84):133-144
Abstract

Until recently, tipi rings received little attention from archaeologists. All of the classic studies of these structures were done more than 20 years ago, and there was little agreement concerning any aspects of stone circles. Recently Plains archaeologists have begun to recognize the importance of tipi rings and to test the hypotheses of earlier authors. During the summer of 1973 the University of Montana Statewide Archaeological Survey conducted excavations of two stone circle sites near Dutton, Montana. This research demonstrates the existence of two types of stone circles and shows that significant information regarding function, use, and settlement pattern can be obtained from the excavation of tipi rings.  相似文献   

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Kidney stone disease is a common health problem in industrialised nations. We developed a SDS-PAGE-based method to quantify Tamm Horsfall glycoprotein (THP) for screening of kidney stone disease. Urinary proteins were extracted by using ammonium sulphate precipitation at 0.27 g salt/mL urine. The resulted pellet was dissolved in TSE buffer. Ten microliters of the urinary proteins extract was loaded and separated on 10% SDS-PAGE under reducing condition. THP migrated as single band in SDS-PAGE. The assay reproducibility and repeatability were 4.8% CV and 2.6% CV, respectively. A total of 117 healthy subjects and 58 stone patients were tested using this assay, and a distinct cut-off (P < 0.05) at 5.6 μg/mL THP concentration was used to distinguish stone patients from healthy subjects. The sensitivity and specificity of the method were 92.3% and 83.3%, respectively.  相似文献   

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The pronounced diurnal rhythm in DNA distribution of the hamster check pouch epithelium both in the S fraction and in the (G2+ M) fraction was compared with previous studies of the changes in tritiated thymidine labelling index and mitotic activity. the DNA distributions were obtained by flow cytometry after ultrasonic disaggregation of the isolated epithelium into a suspension of single nuclei. the DNA distributions were analysed with the computer program of J. Fried (1976) and by planimetry. the S fraction was higher than the autoradiographic labelling index during the whole 24 hr period. Only the computer fitted S fraction and the labelling index had the same difference between maximal and minimal values, and maxima at the same time of day. the DNA distributions showed a diurnal release of G1 cells into S phase proceeding through (G2+ M) phase and returning to G1 phase within a 24 hr period.  相似文献   

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Circadian variations in the proliferative activity of squamous epithelia are well known. However, circadian variations in the duration of the various cell cycle phases (S, G2 and mitosis) have been disputed. the percent labelled mitoses method, which is traditionally used to obtain duration of cell cycle phases, is poorly suited for identification of circadian variations. Therefore methods combining changes in compartment size (cell cycle phase) and cellular flux through the compartments have been used. Three different methods using such data are presented. These incorporate various simplifying assumptions that cause methodological errors. Limits for use of the different methods are indicated. the use of all three methods gives comparable and pronounced circadian variations in the duration of S and G2 phase. These results are also compatible with circadian variations in the mitotic duration, but they may also represent artefacts due to sensitivity to model errors.  相似文献   

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The circadian timing system (CTS) governs the 24-h rhythm of the organism and, hence, also main pathways responsible for drug pharmacokinetics. P-glycoprotein (P-gp) is a drug transporter that plays a pivotal role in drug absorption, distribution, and elimination, and temporal changes in its activity may affect input, output, activity, and toxicity profile of drugs. In the current study, the influence of different circadian stages on the overall intestinal permeability (Peff) of the P-gp substrates talinolol and losartan was evaluated in in situ intestinal perfusion studies in rats. Additionally, in vivo studies in rats were performed by employing the P-gp probe talinolol during the day (nonactive) and night (active) period in rats. Effective intestinal permeabilities of talinolol and losartan were smaller in studies performed during the night (p?<?.05), indicating that P-gp–dependent intestinal secretion is greater during the nighttime activity span than daytime rest span of the animals. P-gp modulators vinblastine and PSC833 led to a significant decrease of talinolol and losartan exsorption in the intestinal segments as compared with control groups. Strikingly, the permeability-enhancing effect of vinblastine and PSC833 was higher with night perfusions, for both talinolol and losartan. In vivo studies performed with talinolol revealed—consistent with the in situ studies (Peff day?>?night)—a day vs. night difference in the oral availability of talinolol in the group of male rats in terms of the area under the curve (AUC) data (AUCday?>?AUCnight). The P-gp modulator vinblastine significantly increased talinolol AUCday (p?<?.05), whereas only a weak vinblastine effect was seen in night. According to the in situ data, the functional activity of P-gp was regulated by the CTS in jejunum and ileum, which are major intestinal segments for energy-dependent efflux. In conclusion, circadian rhythms may affect carrier-mediated active efflux and play a role in the absorption process. In addition to daily rhythms in P-gp activity in rat intestine, the in vivo studies indicate that absorption-, distribution-, metabolism-, and elimination-relevant rhythms may be involved in the circadian kinetics of the drug, besides transporter-dependent efflux, such well-known aspects as metabolic or renal clearance or motility. Since this also holds true for a potentially interacting second compound (modulator), modulator effects should be evaluated carefully in transporter related drug-drug interactions. (Author correspondence: )  相似文献   

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PINOCYTOSIS IN FIBROBLASTS : Quantitative Studies In Vitro   总被引:35,自引:31,他引:35       下载免费PDF全文
Horseradish peroxidase (HRP) was used as a marker to determine the rate of ongoing pinocytosis in several fibroblast cell lines. The enzyme was interiorized in the fluid phase without evidence of adsorption to the cell surface. Cytochemical reaction product was not found on the cell surface and was visualized only within intracellular vesicles and granules. Uptake was directly proportional to the administered concentration of HRP and to the duration of exposure. The rate of HRP uptake was 0.0032–0.0035% of the administered load per 106 cells per hour for all cells studied with one exception: L cells, after reaching confluence, progressively increased their pinocytic activity two- to fourfold. After uptake of HRP, L cells inactivated HRP with a half-life of 6–8 h. Certain metabolic requirements of pinocytosis were then studied in detail in L cells. Raising the environmental temperature increased pinocytosis over a range of 2–38°C. The Q10 was 2.7 and the activation energy, 17.6 kcal/mol. Studies on the levels of cellular ATP in the presence of various metabolic inhibitors (fluoride, 2-desoxyglycose, azide, and cyanide) showed that L cells synthesized ATP by both glycolytic and respiratory pathways. A combination of a glycolytic and a respiratory inhibitor was needed to depress cellular ATP levels as well as pinocytic activity to 10–20% of control values, whereas drugs administered individually had only partial effects. In spite of the availability of an accurate quantitative assay for fluid and solute uptake, the function of pinocytosis in tissue culture cells remains unknown.  相似文献   

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《Endocrine practice》2016,22(4):447-453
Objective: To describe the various patterns of presentation, including assisting analyses, associated with the timing of diagnosis of females with hypopituitarism and suspected clinical diagnosis of lymphocytic hypophysitis.Methods: A retrospective study of 9 consecutive females with pituitary dysfunction developed during or after pregnancy. All subjects were treated in our clinics between 2008 and 2014. Data were collected on clinical characteristics, pituitary hormone levels, and imaging findings.Results: The study group included 9 patients with a mean age 33.7 ± 7.8 years at delivery. The probable cause of disease was lymphocytic hypophysitis. Headache or specific symptoms/signs of hypopituitarism appeared within 1 year of delivery. Five patients had headache, and 8 had difficulty breastfeeding or amenorrhea. Laboratory findings included central hypocortisolism (8/9 patients), hypogonadotropic hypogonadism (8/9), and central hypothyroidism (6/7). Insulin-like growth factor-1 (IGF-1) levels were low in 8/8 patients. Prolactin levels were low in 3/9 patients, and 1 patient had diabetes insipidus. Seven patients were diagnosed less than 1 year from symptom onset; 4 (57%) complained of headaches, and 5 (71%) had panhypopituitarism. Two patients were diagnosed later. Both had difficulty breastfeeding and amenorrhea, and one also had headaches. Both had panhypopituitarism and reduced pituitary volume. None of the patients fully recovered pituitary function. Normalization of the thyrotroph axis occurred in 3 patients, gonadotroph function in 3, the corticotroph axis in 2, and IGF-1 normalized in 1 subject.Conclusion: Hypopituitarism attributed to lymphocytic hypophysitis may present during pregnancy or early postpartum period with a clear clinical picture, or later, with indolent and nonspecific symptoms and signs.Abbreviations:ACTH = adrenocorticotropic hormoneDI = diabetes insipidusFSH = follicle-stimulating hormoneGH = growth hormoneIGF-1 = insulin-like growth factor-1LH = luteinizing hormoneLT4 = levothyroxineMRI = magnetic resonance imagingT4 = thyroxineTSH = thyroid stimulating hormone  相似文献   

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K. WEHLE 《Cytopathology》1993,4(4):231-236
Broncholaveolar lavage (BAL) specimens (n= 213) from AIDS and non-HIV immunosuppressed patients were investigated for the presence of Pneumocystis carinii infection by fluorescence microscopy of Papanicolaou-stained slides. Alveolar casts, extracellular pneumocysts and phagocytosed cysts and their degradation products in pulmonary alveolar macrophages were identified. the number of phagocytosed pneumocysts within human pulmonary alveolar macrophages was recorded and correlated with the number of extracellular cysts and alveolar casts, in both groups of patients. Both phagocytic and degradation capacity were depressed in AIDS patients. This observation may explain the large number of extracellular organisms found in BAL specimens of AIDS patients compared with non-HIV-positive immunocompromised individuals.  相似文献   

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Adventitious buds were induced on isolated immature cotyledons of Pinus pinea L. in the presence of benzyladenine (BA). The response to different BA concentrations also depended upon the culture medium used (modified MS, SH and GD). A wide range of BA concentrations (5, 25 or 50 M) can be applied to the GD and SH media, which are the media with the lower nitrogen content, without damaging effects. In the MS medium, which has the highest nitrogen concentration, the range of BA that can be applied was narrower and the highest BA concentration was lethal. The addition of indolebutyric acid (0.05, 0.25 or 0.5 M) to the induction medium, decreased the response of cotyledons. The increase in the concentration of sucrose from 3% to 5% did not increase the number of responding cotyledons. The addition of activated charcoal (0.5 and 3 g l-1) or indolebutyric acid (1.5 or 3 M) did not speed up the elongation of explants. Elongation of the buds produced shoots with two different phenotypes, each phenotype having a different multiplication rate.Abbreviations BA benzyladenine - GD Gresshoff & Doy medium - IBA indolebutyric acid - MS Murashige & Skoog medium - SH Schenk & Hildebrandt medium  相似文献   

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探讨数量性状变异规律以便对其进行遗传操纵一直是植物遗传学的一个重要领域。DNA分子标记和QTL作图技术的发展以及拟南芥和水稻全基因组测序的完成极大地促进了植物数量性状分子基础的研究。现已克隆了拟南芥ED1、水稻Hdl、玉米Tb1、番茄fw2.2和Brii9-2-5等控制目标数量性状的基因。数量性状表型变异不仅源于多个数量性状基因(QTL)的分离.而且还受到内外环境的修饰。QTL等位基因变异与孟德尔基因变异具有类似的分子基础,即基因表达或蛋白质功能发生改变。通过分析已克隆的植物QTL的变异特征及分子基础,讨论了植物QTL克隆技术策略,并对QTL研究所面临的挑战和应用前景进行了展望。  相似文献   

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Urinary Stone     
John Eager Howard 《CMAJ》1962,86(22):1001
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路南石林     
云南省的路南石林,是以岩柱高大雄伟、姿态多娇、分布广阔而闻名世界的喀斯特地貌,为我国首批公布的国家重点风景名胜区和国家地质公园。 石林,因成千上万根的石灰岩岩柱拔地而生得名,号称天下第一奇观,它们当中那些拟人拟物的形象更是千姿百态、栩栩如生,当地的撒尼族人民就曾流传很多的民间故事,差不多每块石头都有一段神话般的传说。然而,人们已经不满足于这些神话传说了,常常刨根问底,想知道大自然是如何锻造出这样的奇观。  相似文献   

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