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1.
This study aimed to investigate the levels of serum low-density lipoprotein cholesterol (LDLC) using direct measurement in healthy Japanese school children. The subjects were 621 children (325 boys and 296 girls) aged 9 to 10 in the 4th grade, and 688 children (334 boys and 354 girls) aged 12 to 13 in the 7th grade. The levels of serum LDLC and high-density lipoprotein cholesterol were measured by direct determination (Cholestest LDL and Cholestest NHDL; Daiichi Pure Chemicals Co., Ltd., Tokyo, Japan). In boys in the 4th grade, the mean, the 75th, the 90th and the 95th percentiles of LDLC levels (mg/dl) were 91.6, 104, 124 and 134, respectively. In girls in the 4th grade, they were 92.8, 108, 122 and 130. In boys in the 7th grade, they were 83.4, 96, 113 and 123. In girls in the 7th grade, they were 93.0, 106, 126 and 137. Serum LDLC levels in boys in the 7th grade were lower than those of other groups. The direct measurement of serum LDLC level is useful for evaluation of dyslipidemia in healthy school children, because the method is applicable to non-fasting serum.  相似文献   
2.
A case of acquired immunodeficiency syndrome (AIDS) with preceding aplastic anemia is reported. The patient was a 36 year old female who had been diagnosed as having aplastic anemia 10 years before and thereafter had received multiple transfusions. Human immunodeficiency virus (HIV)-seropositivity was revealed 10 months prior to her death, but no particular clinical signs indicating HIV infection, pre-AIDS or onset of AIDS were recognized before serological diagnosis, although the slow progression of leukopenia was noted along with thrombocytopenia. Her general condition deteriorated during the last 10 months accompanied by an acute decrease In the CD4/CD8 ratio. Autopsy revealed full-blown AIDS: systemic aspergillosis, progressive multifocal leukoencephalopathy, Epstein-Barr virus-related B cell lymphoma arising in the diaphragm and severe lymphocyte depletion in the lymph nodes and spleen. Markedly hypo-plastic bone marrow was considered to be primarily attributable to the aplastic anemia but the affection of AIDS was not excluded. The possible transmission route of HIV and the effect of the preceding aplastic anemia on the infection and clinical course of AIDS are discussed.  相似文献   
3.
Radical copolymerization of 4-(trimethylsilyl)styrene (TMSS) with styrene were carried out to estimate the reactivity of TMSS. The monomer reactivity ratios r1 and r2 in the radical copolymerization of TMSS (M1) with styrene (M2) were evaluated as 0,28 and 0,48, respectively. The value r1 · r2 (= 0,13) being smaller than unity indicates that the trimethylsilyl group at para position behaves as an electron-withdrawing substituent. Reactions of lithium diethylamide with TMSS in the presence of diethylamine, gave the 1:1 addition product 1-[2-(N,N-diethylamino)-ethyl]-4-(trimethylsilyl)benzene. Kinetic analysis showed that the second-order rate constant (k) for this addition reaction is 34,4 · 10?4 dm3 · mol?1 · s?1, which is by a factor of 2 larger than that for the reaction with styrene (k = 16,0 · 10?4 dm3 · mol?1 · s?1). The fact is also compatible with the above consideration for the r1 · r2 values. Lithium diisopropylamide initiated anionic copolymerizations of TMSS with 1,4-divinylbenzene (DVB) were also examined. The polymerizations proceed smoothly without any gel formation and the resulting copolymers are soluble in various common solvents such as benszene, tetrahydrofuran, chloroform, etc. Thus, novel organosilicon-containing polymers having appropriate amounts of reactive pendent vinyl groups are easily synthesized.  相似文献   
4.
Pilon fractures with intact fibula have been associated with low-energy trauma. However, the compression force onto the ankle joint can damage the tibiofibular linkage as in a Maisonneuve fracture. Herein, we describe a case of a patient who had a pilon fracture (AO type 43 C3.2) without a fibular fracture. Three-dimensional preoperative simulation by reduction with the surface registration technique was performed as the fibular length was intact and there was no reference for the tibial length. The preoperative simulation revealed superior fibular head dislocation and shortening of the distal tibia. After emergency external fixation on the day of arrival, a 2-staged surgery was performed. During the first operation, the fibular head was reduced and the tibial posterolateral fragment was fixed to restore the tibia length. During the second operation, medial and anterolateral fragments were fixed in order to reduce joint surface of the distal tibia. In general, proximal fibular head fractures are easily overlooked. In the case of pilon fractures with severe length shortening of the tibia without a fibular fracture, a proximal tibiofibular injury should be suspected.  相似文献   
5.
Synthesis and gas permeation measurements of several types of polymers from methylstyrene derivatives containing mono-and bis(trialkylsilyl) group(s) were carried out. Upon radical homo-and co-polymerization of silicon-containing monomers high-molecular-weight polymers were obtained. Results from gas permeation measurements showed that these types of silicon-containing polymers exhibit fairly high oxygen permselectivity (ratio of oxygen and nitrogen permeation coefficients P/P = 3,1 ? 4,6), keeping the oxygen permeation coefficients (P) in the range of between 1,4 · 10?9 and 4,5·10?9 cm3 (STP) · cm · cm?2 · s?1 · cmHg?1. From time lag measurements, it was found that permeation coefficients are dependent on the solubility of gases in the membranes rather than on diffusivity. Actually, the oxygen solubility coefficients increase with increasing silicon content in the polymers. Permselectivity of oxygen against nitrogen is governed by polymer constitution rather than by silicon content.  相似文献   
6.
The present study examined alterations of brain noradrenaline (NA) turnover as a function of preshock and psychological stress treatments, by measuring contents of NA metabolite, 3-methoxy-4-hydroxyphenylethyleneglycol sulfate (MHPG-SO4), in discrete brain regions of male Wistar rats. Psychological stress induced by exposing to the sight, sound and odor of other rats being shocked produced higher levels of MHPG-SO4 in the hypothalamus, amygdala and locus coeruleus (LC) region, as well as higher levels of plasma corticosterone. Preshock experienced rats also showed marked increases of MHPG-SO4 levels in the same regions described above and elevated plasma corticosterone levels when placed but not shocked in the same environment in which the rats had previously received shocks. The effects of psychological stress on brain NA turnover were affected by the animal's shock history preferentially in the hypothalamus and amygdala. These results suggest that: a purely psychological stressor caused acutely enhanced NA turnover in specific brain regions; regional NA activity appeared to be reinstated simply by reexposure to the environment previously associated with shock; preshock experience further intensified the enhancement of amygdaloid NA turnover evoked by psychological stress. An additional experiment, studying the aftereffects of preshock experience, clearly showed that these findings result from sensitization or conditioning to the environment previously paired with shock, and not merely from the aftereffects of the shock per se.  相似文献   
7.
International Journal of Clinical Oncology - We assessed the technical and oncological safety of self-expandable metallic stent (SEMS) insertion followed by laparoscopic colorectal surgery as a...  相似文献   
8.
9.
Prolonged exposure of tissues to a receptor agonist often leads to adaptive changes that limit the subsequent responsiveness of the tissue to the same agonist. Recently, we have generated rats transgenic for the metallothionein I-human arginine vasopressin (AVP) fusion gene (Tg), which produced high plasma AVP with relatively preserved renal water excretion, suggesting that there might be adaptive mechanism(s) for maintaining water and electrolyte homeostasis against chronic AVP oversecretion from the earliest stage of life. In this study, to investigate whether down-regulation of AVP V2 receptor (V2R), which could possibly be caused by long-standing high plasma AVP, participates in this adaptive mechanism(s), non-peptidic V2R antagonist OPC31260 was administered to reverse the down-regulation, and water loading was performed after V2R antagonist treatment had been withdrawn. Additionally, to confirm the down-regulation, Northern blotting analysis for V2R mRNA was carried out. Tg rats showed slightly decreased urine volume and water intake with an equivalent plasma [Na(+)] level (Tg 140.4 +/- 0.6 mEq/l; control 139.3 +/- 0.6 mEq/l) under basal conditions. After water loading using a liquid diet containing zinc, which stimulates the promoter region in the transgene, the urine increase showed only limited suppression with a dramatically increased plasma AVP level and mild hyponatremia (135.8 +/- 1.8 mEq/l) in Tg rats. When diet containing OPC31260 had been provided for 4 days until the day before the start of water loading, antidiuresis and hyponatremia (125.4 +/- 1.mEq/l) were significantly potentiated. V2R mRNA expression in kidney was significantly less in Tg rats than in control rats under basal conditions, and this suppression was restored by OPC31260 treatment to levels comparable with those of control rats. These results suggest that long-standing high plasma AVP causes V2R down-regulation, and it may play an important role in the adaptive mechanism(s) for maintaining water and electrolyte homeostasis in chronically AVP-overexpressing rats.  相似文献   
10.
Hypothyroidism is associated with increased morbidity from cardiovascular disease, and an increase in serum osteoprotegerin (OPG) has recently been reported to be associated with the severity of coronary heart disease and cardiovascular mortality. The present study was designed to examine whether hypothyroidism causes an increase in serum OPG, and to determine whether levothyroxine (L-T4) replacement therapy might suppress serum OPG levels in hypothyroid patients. Fifty-three hypothyroid patients with chronic thyroiditis and age- and sex-matched normal control subjects were examined for the levels of serum OPG and plasma von Willebrand factor (vWF), a vascular injury marker. Thirty-seven of the hypothyroid patients were further monitored for changes in these markers during 1 year in a euthyroid state induced by L-T4 replacement therapy. Baseline OPG was significantly higher in hypothyroid patients than in normal controls (4.51 +/- 0.50 vs 3.72 +/- 0.23 pmol/l (mean +/- S.E.); P = 0.0182). In multivariate analysis, baseline OPG was significantly associated with baseline levels of TSH (r = 0.280, P = 0.0162) and vWF (r = 0.626, P < 0.0001). During one year of L-T4 replacement therapy, hypothyroid patients showed a significant decrease in OPG levels from 4.35 +/- 0.51 to 3.48 +/- 0.26 pmol/l (P = 0.0166), a level comparable to normal controls. The change in serum OPG levels during L-T4 replacement therapy was significantly and independently associated in a negative fashion with baseline vWF (r = -0.503, P = 0.0014). This study suggested that the severity of hypothyroidism and vascular injury might have important independent roles in increasing the serum OPG level in hypothyroid patients. Furthermore, it was demonstrated that a sustained euthyroid state might have the potential to decrease the serum OPG level in hypothyroid patients and that the degree of vascular injury in the hypothyroid state is independently associated with a decrease in serum OPG during a 1-year normalization of thyroid function.  相似文献   
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