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61.
62.
J H Olsen S Garwicz H Hertz G Jonmundsson F Langmark M Lanning S O Lie P J Moe T M?ller R Sankila et al. 《BMJ (Clinical research ed.)》1993,307(6911):1030-1036
OBJECTIVE--To assess the relative risk of developing a second malignant neoplasm in people with a diagnosis of cancer in childhood and adolescence. DESIGN--Register based follow up study. SETTING--Populations of Nordic countries. SUBJECTS--30,880 people under the age of 20 with a first malignant neoplasm diagnosed during the period 1943-87. MAIN OUTCOME MEASURES--Relative and attributable risks of second malignant neoplasms by type of first cancer, age at first diagnosis, calendar period, sex, and country. Expected figures were based on the appropriate national incidence rates for cancer. RESULTS--247 cases of second malignant neoplasms were observed in 238 patients, yielding a relative risk for cancer of 3.6 (95% confidence interval 3.1 to 4.1). The risk changed significantly from 2.6 in people first diagnosed during the 1940s and 1950s to 6.9 among cohort members included in the late 1970s and 1980s. Increases were observed for most types of cancer. Highest levels of the relative risk were seen during the 10 years immediately after first malignant diagnosis. The incidence of second malignant neoplasms attributable to the first cancer and associated treatments, however, showed a consistent rise throughout the 45 years of follow up. CONCLUSION--The estimated risks for a second malignant neoplasm were significantly lower than those found in most large hospital based studies but compatible with the results from a similar population based study in the United Kingdom. Extent of risk and cancer pattern were similar among the Nordic countries and are believed to be representative for a large part of the European population. 相似文献
63.
Albert de la Chapelle Seppo Similä Marjatta Lanning Matti Kontturi Carl-Johan Johansson 《Human genetics》1971,11(4):286-294
Summary Two males with the karyotype 46,XX are reported. In both individuals, the karyotype was determined in over 400 cells from lymphocyte, skin, and testis cultures.Case 1, a man born in 1935, had a normal male appearance. The Xg blood group distribution in his family was: father Xg(a+), mother Xg(a-), and propositus xg(a-). Case 2, a boy born in 1964, had penoscrotal hypospadias, and a small penis and scrotum, but otherwise appeared normal.Results of clinical, histological, genetical and blood group investigations are given. 相似文献
64.
65.
This paper looked at the leaf architecture characteristics of Vachellia tortilis to determine if either there is or not an effect of the tropic line on plants. Vachellia tortilis leaves were sampled along a national road (N1) in Limpopo province. Sampling points were set 10 km apart away from the Tropic of Capricon in opposite directions. Leaf morphology revealed that leaves of V. tortilis are bipinnately compound with alternate arrangement. The venation pattern of the pinnules was eucamptodromus and brochidodromous with imperfect reticulation. Areoles were imperfect and pentagonal or irregular in shape. 相似文献
66.
67.
Sodium balance determines the extracellular fluid volume and sets arterial blood pressure (BP). Chronically raised BP (hypertension)
represents a major health risk in Western societies. The relationship between BP and renal sodium excretion (the pressure/natriuresis
relationship) represents the key element in defining the BP homeostatic set point. The renin–angiotensin–aldosterone system
(RAAS) makes major adjustments to the rates of renal sodium secretion, but this system works slowly over a period of hours
to days. More rapid adjustments can be made by the sympathetic nervous system, although the kidney can function well without
sympathetic nerves. Attention has now focussed on regulatory mechanisms within the kidney, including extracellular nucleotides
and the P2 receptor system. Here, we discuss how extracellular ATP can control renal sodium excretion by altering the activity
of epithelial sodium channels (ENaC) present in the apical membrane of principal cells. There remains considerable controversy
over the molecular targets for released ATP, although the P2Y2 receptor has received much attention. We review the available data and reflect on our own findings in which ATP-activated
P2Y and P2X receptors make adjustments to ENaC activity and therefore sodium excretion. 相似文献
68.
Marcel GA van der Heijden Susanne de Bruin Ludo Luckerhoff Richard SP van Logtestijn Klaus Schlaeppi 《The ISME journal》2016,10(2):389-399
Highly diverse microbial assemblages colonize plant roots. It is still poorly understood whether different members of this root microbiome act synergistically by supplying different services (for example, different limiting nutrients) to plants and plant communities. In order to test this, we manipulated the presence of two widespread plant root symbionts, arbuscular mycorrhizal fungi and nitrogen-fixing rhizobia bacteria in model grassland communities established in axenic microcosms. Here, we demonstrate that both symbionts complement each other resulting in increased plant diversity, enhanced seedling recruitment and improved nutrient acquisition compared with a single symbiont situation. Legume seedlings obtained up to 15-fold higher productivity if they formed an association with both symbionts, opposed to productivity they reached with only one symbiont. Our results reveal the importance of functional diversity of symbionts and demonstrate that different members of the root microbiome can complement each other in acquiring different limiting nutrients and in driving important ecosystem functions. 相似文献
69.
We recently reported that bile salts play a role in the regulation of mucin
secretion by cultured dog gallbladder epithelial cells. In this study we
have examined whether bile salts also influence mucin secretion by the
human epithelial colon cell line LS174T. Solutions of bile salts were
applied to monolayers of LS174T cells. Mucin secretion was quantified by
measuring the secretion of [3H]GlcNAc labeled glycoproteins. Both
unconjugated bile salts as well as taurine conjugated bile salts stimulated
mucin secretion by the colon cells in a dose-dependent fashion. Hydrophobic
bile salts were more potent stimulators than hydrophilic bile salts. Free
(unconjugated) bile salts were more stimulatory compared with their taurine
conjugated counterparts. Stimulation of mucin secretion by LS174T cells was
found to occur at much lower bile salt concentrations than in the
experiments with the dog gallbladder epithelial cells. The protein kinase C
activators PMA and PDB had no stimulatory effect on mucin secretion. We
conclude that mucin secretion by the human colon epithelial cell line
LS174T is regulated by bile salts. We suggest that regulation of mucin
secretion by bile salts might be a common mechanism, by which different
epithelia protect themselves against the detergent action of bile salts, to
which they are exposed throughout the gastrointestinal tract.
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