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排序方式: 共有534条查询结果,搜索用时 15 毫秒
471.
472.
473.
474.
吡咯-2-甲醛缩N4-(4-甲氧基苯基)氨基脲抗实验性大鼠溃疡作用 总被引:4,自引:0,他引:4
化合物Ⅰ具有与呋喃唑酮相似的抗实验性大鼠溃疡活性,但小鼠口服急性毒性较后者小。化合物Ⅰ在剂量为40~100 mg/kg时对五种大鼠溃疡模型(消炎痛型、幽门结扎型、慢性醋酸型、和无水乙醇引起的大鼠溃疡模型)均有较好保护作用,但对水拘急性应激型溃疡无效。对胃酸分泌无明显影响,对胃蛋白酶分泌有轻度抑制作用;具有“细胞保护”样作用,对HCl和无水乙醇引起的大鼠溃疡显示出较好的保护作用;增加幽门结扎大鼠胃液中氨基己糖的含量,降低DNA含量。 相似文献
475.
Polycystic ovary syndrome (PCOS) is a common reproductive disorder
characterized by arrested follicular development prior to selection of a
dominant follicle. Dominant follicles produce large amounts of oestradiol
but PCOS follicles do not. With several potential aromatase (P450AROM)
inhibitors in follicular fluid, the question arises whether P450AROM is
expressed in PCOS granulosa cells, but the activity is inhibited, or
whether P450AROM is not expressed in PCOS. The purpose of the present study
was to determine whether P450AROM mRNA expression is altered in PCOS and to
correlate P450AROM mRNA expression in individual follicles with aromatase
stimulatory bioactivity and oestradiol in the follicular microenvironments.
P450AROM mRNA was measured in individual follicles from 16 PCOS and 48
regularly cycling control women by quantitative polymerase chain reaction
(PCR) and correlated with follicular fluid oestradiol concentrations and
aromatase stimulating bioactivity measured by the rat granulosa cells
aromatase bioassay. Follicular fluid oestradiol was low in all control
follicles <7 mm in diameter. Some follicles > or = 7 mm contained
elevated oestradiol values (P < 0.01) and all had an
androstenedione:oestradiol ratio of <4. Only in granulosa cells from
follicles > or = 7 mm with an androstenedione:oestradiol ratio of <4
were P450AROM mRNA levels increased (P < 0.05). These same follicles
also contained increased levels of aromatase stimulating bioactivity
whereas follicles <7 mm or with androstenedione:oestradiol ratio of
>4 contained little or no bioactivity. All PCOS follicles contained low
levels of oestradiol, P450AROM mRNA and aromatase stimulating bioactivity
similar to size- matched control follicles. These data indicate that
P450AROM mRNA expression and oestradiol production begin in developing
follicles when they reach approximately 7 mm in diameter. Oestradiol
production is low in PCOS follicles because there is insufficient aromatase
stimulating bioactivity to increase P450AROM mRNA expression.
相似文献
476.
Seventy-one children with nocturnal enuresis were enrolled in a controlled trial. The children were allocated to two matched groups. Children in both groups used an enuresis alarm until the end of treatment. Children in the first group were treated with 40/^g of intranasal desmopressin (Desmospray) for up to 6 weeks at the start of treatment with the alarm. During the observation period before treatment there were 2.3 dry nights per week in both groups. At the end of treatment there was a significant difference in the mean number of dry nights per week between the two groups (6.3 in the alarm and desmopressin group and 4.8 in the alarm group) and also in the number of children becoming reliably dry. The combination of desmopressin and alarm was particularly helpful for children with severe wetting and those with family and behavioural problems. Desmopressin, enuresis alarm, nocturnal enuresis
MG Bradbury, Department of Paediatrics and Child Health, St James's University Hospital, Leeds LS9 7TF, UK 相似文献
MG Bradbury, Department of Paediatrics and Child Health, St James's University Hospital, Leeds LS9 7TF, UK 相似文献
477.
In order to investigate specific DNA damage caused by nitric oxide (NO)
induced lipid peroxidation, levels of promutagenic etheno adducts 1,N6-
ethenodeoxyadenosine (epsilondA) and 3,N4-ethenodeoxycytidine (epsilondC)
were measured in spleen DNA of SJL mice induced to produce high levels of
NO by injection of RcsX (pre-B-cell lymphoma) cells. epsilondA and
epsilondC levels were quantified by an ultrasensitive
immunoaffinity-32P-post-labeling method. Spleen DNA of control mice (n = 5)
had background levels of 9.2+/-5.4 epsilondA adducts per 10(9) dA and
13.1+/-5.7 epsilondC adducts per 10(9) dC. In RcsX cell-injected mice (n =
7), levels of these adducts were elevated approximately 6- fold, i.e.
53.9+/-39.4 epsilondA per 10(9) dA and 83.5+/-57.8 epsilondC per 10(9) dC
(P < 0.05). Mice injected with RcsX cells and also treated with
NG-methyl-L-arginine (NMA), an inhibitor of inducible nitric oxide synthase
(n = 6), had significantly reduced levels (P < 0.05) of both epsilondA
and epsilondC (13.5+/-5.7 epsilondA per 10(9) dA and 28.2+/- 15.7 epsilondC
per 10(9) dC). These findings constitute the first available evidence of
formation of etheno adducts associated with NO overproduction in vivo. The
adducts were presumably formed from lipid peroxidation products such as
trans-4-hydroxy-2-nonenal (HNE), generated via oxidation of lipids by
peroxynitrite. The results suggest that etheno-DNA adducts, among other
types of damage, may contribute to the etiology of cancers associated with
chronic infection/inflammation in which NO is overproduced.
相似文献
478.
Precipitants and aetiology of cyclic vomiting syndrome 总被引:3,自引:0,他引:3
Thirty-two patients aged 2-22 y with cyclic vomiting syndrome (CVS), and 64 age- and gender-matched controls were assessed to determine the nature, severity, precipitants and associated features of attacks and the incidence of potential aetiological factors. The mean age of onset was 3.5 y. Patients experienced a mean of nine attacks per year, of average duration 2.4 d, and two-thirds missed more than 10 d of school per year. Patients were more likely to have migraine and co-ordination difficulties, a past history of forceps delivery and gastroesophageal reflux than controls. Compared with controls, subjects had a higher incidence of psychological symptoms (38% compared with 19%) and migraine (37% compared with 9%). CVS is a chronic, disabling condition and is a migraine variant, with attacks usually precipitated by stress and intercurrent infections. 相似文献
479.
F Jalil BS Lindblad LÅ Hanson SR Khan M Yaqoob J Karlberg 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(S391):95-107
In Pakistan there are a number of acute problems related to maternal and infant health in the perinatal period. There is also lack of reliable data needed for the formulation of action strategies. To provide a database 1490 women have been followed from the 5th month of pregnancy in four different areas at various levels of urbanization and socio-economic development. After adjusting for gestational age, the proportion of newborns with weight for length < -2SDS in relation to the Swedish National Standard was 12–31% for boys and 12–25% for girls, the figure being highest in the most deprived area. Preterm birth was infrequent compared with IUGR. The overall prevalence rate of birth defects was 21% out of which 8% were severe defects. The overall perinatal mortality rate was 56/1000 births, with rates of 60, 75, 36 and 33/1000 births for the village, periurban slum, urban slum and the upper middle class. Two thirds of the deaths were related to either a continuation of intrauterine disturbances or severe congenital defects incompatible with life. One third of the deaths were due to infection; mostly diarrhoea, clinical sepsis and ARI. Neonatal mortality was significantly related to birth length (<-2SDS, odds ratio 5.5) and length of gestation (<37 weeks, odds ratio 5.6) and was to a lesser extent related to weight (<-2SDS, odds ratio 2.0) and weight for length (<-2SDS, odds ratio 1.3). Forty percent of the mothers had weight for height below -2SDS, 23–35% had height <-2SDS. Forty percent of mothers from a subset within the cohort had a hemoglobin < 10 gm/dl and 20% showed signs of pre-eclampsia. This presentation raises the issue of expanding the current Child Survival Programs into the perinatal period as well. 相似文献
480.