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81.
Breath-hold, contrast-enhanced, three-dimensional MR angiography 总被引:22,自引:0,他引:22
82.
Marieke Hiemstra Linda Ringlever Roy Otten Christine Jackson Onno CP van Schayck Rutger CME Engels 《BMC public health》2009,9(1):477
Background
A strong increase in smoking is noted especially among adolescents. In the Netherlands, about 5% of all 10-year olds, 25% of all 13-year olds and 62% of all 17-year olds report ever smoking. In the U.S., an intervention program called 'Smoke-free Kids' was developed to prevent children from smoking. The present study aims to assess the effects of this home-based smoking prevention program in the Netherlands. 相似文献83.
Multiple myeloma is often associated with humoral immunodepression in both man and mouse. When mice bearing the humorally immunodepressive plasmacytomas TEPC-183 and SPQC-11 were injected with SRBC, the rise of serum haemolysins was significantly less than that of non-tumour-bearing mice. Mice with the plasmacytomas MPC-11 and MOPC-315 have an antibody response similar to normal mice when injected with SRBC. Following immunization, normal mice and those bearing MPC-11 showed a 2- to 3-fold increase in total spleen lymphocytes. Mice bearing TEPC-183 or SPQC-11, the plasmacytomas causing an impaired antibody response, has significant increase in spleen lymphocytes under the same conditions. Mice bearing MOPC-315 had a very high initial count of spleen lymphocytes, which did not further increase upon immune stimulation. 相似文献
84.
85.
Stefan M. Pojda Ryszard Brus 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1976,200(3):223-226
Summary Male Wistar rats were injected intraventricularly with two doses of 250 mcg of 6-hydroxydopamine (6-OHDA) in two consecutive days. Two weeks later the oxygen uptake, anaerobic glycolysis and lactic acid dehydrogenase (LDH) activity in the retina were determined. The decrease of oxygen uptake (–28 %), anaerobic glycolysis (–31 %) and LDH activity (–12 %) in rats treated with 6-OHDA in comparison to control animals was found. The possible role of the adrenergic system in regulation of the metabolism of the retina is discussed.
Zusammenfassung Männlichen Wistarratten wurde an zwei aufeinanderfolgenden Tagen 250 mcg 6-Hydroxydopamin (6-OHDA) intraventrikulär injiziert. Zwei Wochen später wurden Sauerstoffaufnahme, anaerobe Glykolyse und Laktatdehy-drogenaseaktivität (LDH) in der Retina bestimmt. Man fand bei den mit 6-OHDA behandelten Ratten im Vergleich zu Kontrolltieren eine Abnahme der Sauerstoffaufnahme (–28 %), der anaeroben Glykolyse (–31 %) und der LDH-Aktivität (–12 %). Die mögliche Beteiligung des adrenergen Systems an der Regulation des Retinastoffwechsels wird diskutiert.相似文献
86.
87.
Richard M. Kostrzewa Craig T. Harston Hideki Fukushima Ryszard Brus 《Brain research bulletin》1982,9(1-6)
In order to attain a better understanding of the sprouting response of noradrenergic fibers in the central nervous system (CNS), noradrenergic innervation to the cerebellum was observed by the glyoxylic acid method after a variety of manipulations and in a genetic variant of mouse classified as “Purkinje cell degeneration” (pcd/pcd). It has been found that a midbrain lesion in rats at birth will result in a collateral sprouting response of noradrenergic fibers in the cerebellum at 8 weeks, as indicated by the increased number of histofluorescent fibers observed in the molecular layer of the cerebellar cortex. Another procedure, treatment of neonatal rats with nerve growth factor alone appears to produce a temporary stimulation of noradrenergic fiber growth in the cerebellum, as observed by the histofluorescent method, although the innervation at 6 weeks or later is ultimately unchanged from the control group. In contrast, NGF (500 units) given to rats in combination with 6-hydroxydopa (6-OHDOPA) (60 μg/g IP) at 3 days postbirth produces a hyperinnervation of the cerebellum by noradrenergic fibers by 2 weeks of age and until at least 8 weeks of age. A third procedure, locus coeruleus implantation, was generally unsuccessful using the procedures described, since the implant was usually non-viable after several days. In a few instances where histofluorescent nuclei were found within the implant, there was an abundance of histofluorescent fibers within and adjacent to the implant, with fibers appearing to grow into host cerebellum. In the final procedure, it was noted that the density of noradrenergic input to the molecular layer of the cerebellar cortex was markedly increased in a genetic mutant mouse, classified as “Purkinje cell degeneration” (pcd/pcd), which is characterized by the absence of Purkinje cells of the cerebellum in adulthood. However, because of the tissue shrinkage that occurs after loss of Purkinje cells during postnatal development, it is unclear as to whether this observation represents hyperinnervation or a normal complement of fibers in a smaller brain space. The above procedures demonstrate the plasticity of noradrenergic fibers in neonatal cerebellum, a brain region that undergoes considerable postnatal development. The cerebellum is thought to be a good site for studying development/ regeneration/sprouting of noradrenergic fibers in particular, and central axonal processes in general. 相似文献
88.
Nowak P Zagził T Konecki J Szczerbak G Szkilnik R Niwiński J Gorzałek J Kostrzewa RM Brus R 《Pharmacological reports : PR》2006,58(4):559-561
Trimetazidine, a clinically effective antianginal agent with no negative inotropic or vascular properties, acts by optimizing cardiac energy metabolism through inhibition of free fatty acid oxidation, shifting substrate utilization from fatty acids to glucose. Up to now there has been no study associating trimetazidine's effect on metabolic processes with glucose utilization in the mammalian brain. The objective of the present study was to determine if trimetazidine altered [(3)H]glucose uptake in rat brain. Adult male Wistar rats were administered trimetazidine (Metazydyna, Polfa) either as a single dose (10.0 mg/kg po) or for 14 consecutive days (5.0 mg/kg po per day) or vehicle saline (2.0 ml/kg po). Sixty minutes after the single dose or 14th dose of trimetazidine, and 15 min before experiment termination and brain dissection, 6-[(3)H]D-glucose (500 Ci/kg ip; Amersham) was administered. Using liquid scintillation counting, trimetazidine, either in a single or multiple dose regimen, was found to increase [(3)H]glucose uptake (DPM/100 mg of wet tissue) in all dissected regions of the brain (i.e., striatum, hippocampus, frontal cortex, thalamus with hypothalamus, pons with medulla oblongata, and cerebellum). Therefore, central effects need to be taken into consideration as possibly adding to known beneficial cardiac effects of trimetazidine. 相似文献
89.
Brus F Vandewall M Molenschot MM van Setten PA Landstra AM 《Nederlands tijdschrift voor geneeskunde》2006,150(27):1489-1493
4 children, boys aged 12, 5, 1.5 and 11 years, had a heart murmur. The 12-year-old boy could also not finish a football match and appeared to have atrioseptal defects (ASD). The 1.5-year-old boy had pulmonary symptoms that were not responsive to asthma medication; he also had ASD. The 11-year-old boy had had chest pain and pressure following exertion for 2 years; he appeared to have an aortic stenosis. Symptoms disappeared in all 3 patients after surgical correction. In the 5-year-old asymptomatic boy the murmur was deemed to be innocent following medical history and physical examination. Children frequently have heart murmurs. Most heart murmurs are innocent but some are caused by heart defects. Careful evaluation of the medical history and physical examination are critical in the differentiation of innocent and pathological heart murmurs. Routine supplementary diagnostic tests in children with heart murmurs are of limited value and are often misleading. One should inquire about specific and nonspecific symptoms and also perform systematic inspection, palpation and auscultation to identify any characteristics that suggest a heart murmur caused by a heart defect. 相似文献
90.
The metabolism of an essential amino acid, isoleucine, by human leukemic and gradient-separated normal human leukocytes of various types and maturity was studied. Blood leukocytes were isolated and incubated with (U-14C) isoleucine. Separation of metabolic intermediates was accomplished by sequential extraction. The rate of isoleucine incorporation into protein by immature cells from untreated patients with acute leukemia (15.9 plus or minus 2.4 nmoles/hr per 10-8 leukocytes) was considerably higher than the rates of incorporation by mature neutrophils (3.2 plus or minus 0.5 nmoles/hr per 10-8 leukocytes), lymphocytes (7.7 plus or minus 1.2 nmoles/hr per 10-8 leukocytes), and eosinophils (6.2 plus or minus 1.3 nmoles/hr per 10-8 leukocytes). Those cell preparations with more blast cells had higher rates of protein synthesis. In addition, those cells with greater thymidine incorporation had higher rates of protein synthesis. The leukocytes both oxidized isoleucine and incorporated it into cell isoleucine and incorporated it into cell lipid. The rates of these metabolic processes were characteristic for various types and maturity of leukocytes. This study demonstrates a relationship of rate of protein synthesis to leukocyte immaturity. This relationship is maintained in neoplastic leukocytes. It suggests that the requirement of the mitotic process for newly synthesized protein is greater than that for the elaboration of the protein products of the mature leukocyte. 相似文献