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21.
Anne M. Von Euler R. Margareta Mü ller Godfried M. Roomans Ove Ceder 《Ultrastructural pathology》1983,5(1):37-44
The effects of cystic fibrosis (CF) serum and culture medium from CF fibroblasts on ion distribution in rat submandibular gland cells were investigated by X-ray microanalysis. These effects were compared to the effects of normal serum and culture medium from normal fibroblasts, of cholinergic and adrenergic agonists, and of the uncoupler 2,4-dinitrophenol.
Incubation of gland tissue with CF serum or normal serum caused a significant decrease in potassium and calcium concentrations and an increase in sodium in mucous acinar and serous granular duct cells. CF serum gave a significantly larger decrease of the potassium level than normal serum.
Culture medium from CF fibroblasts altered the cellular ion content in a way similar to CF serum. Exposure to medium from cultured normal fibroblasts did not affect the elemental composition of the gland cells significantly, compared to incubation with fresh medium or buffer. Hence, fibroblast culture medium is more suitable than serum to test specific effects of CF-associated factors.
The changes in elemental composition of gland eelIs caused by CF serum or CF fibroblast culture medium mimic some of the effects of the agonist car-bachol. They could, however, also in part result from nonspecific changes in membrane permeability. 相似文献
Incubation of gland tissue with CF serum or normal serum caused a significant decrease in potassium and calcium concentrations and an increase in sodium in mucous acinar and serous granular duct cells. CF serum gave a significantly larger decrease of the potassium level than normal serum.
Culture medium from CF fibroblasts altered the cellular ion content in a way similar to CF serum. Exposure to medium from cultured normal fibroblasts did not affect the elemental composition of the gland cells significantly, compared to incubation with fresh medium or buffer. Hence, fibroblast culture medium is more suitable than serum to test specific effects of CF-associated factors.
The changes in elemental composition of gland eelIs caused by CF serum or CF fibroblast culture medium mimic some of the effects of the agonist car-bachol. They could, however, also in part result from nonspecific changes in membrane permeability. 相似文献
22.
The disposition of the plasticizer di-(2-ethylhexyl) phthalate (DEHP) and four of its major metabolites was studied in male rats given single infusions of a DEHP emulsion in doses of 5, 50 or 500 mg DEHP/kg body weight. Plasma concentrations of DEHP and metabolites were followed for 24 h after the start of the infusion. The kinetics of the primary metabolite mono-(2-ethylhexyl) phthalate (MEHP) was studied separately.The concentrations of DEHP in plasma were at all times considerably higher than those of MEHP, and the concentrations of MEHP were much higher than those of the other investigated metabolites. In animals given 500 mg DEHP/kg, the areas under the plasma concentration-time curves (AUCs) of the other investigated metabolites were at most 15% of that of MEHP. Parallel decreases in the plasma concentrations of DEHP, MEHP and the and (-1) oxidized metabolites indicated that the elimination of DEHP was the rate-limiting step in the disposition of the metabolites. This was partly supported by the observation that the clearance of MEHP was higher than that of DEHP. Nonlinear increases in the AUCs of DEHP and MEHP indicated saturation in the formation as well as the elimination of the potentially toxic metabolite MEHP. 相似文献
23.
Hjördis Högberg Petra Pålsson Fredrik Spak Margareta Larsson Michael B. Wells 《Health & social care in the community》2021,29(6):1896-1914
The aim is to test the reliability of two alcohol screening instruments: (1) The Parent Alcohol Screening Questionnaire (PASQ5), and (2) the Social Support for an Alcohol-free Pregnancy (SSAFP) questionnaire. This is a cohort study from the south of Sweden using repeated surveys during pregnancy. To examine if responses differed according to different data collection methods, two cohorts consisting of 289 expectant mothers and 141 fathers completed the PASQ5 both verbally (weeks 6–7) and in writing (week 12) within regular antenatal visits. One of the cohorts (n = 137/64) also completed the SSAFP in week 12 and later in week 33. The third cohort, consisting of 179 and 133 expectant mothers and fathers, respectively, completed the PASQ5 and the SSAFP twice in late pregnancy (week 31 + 33). Eight of 10 items in the PASQ5 were stable for both expectant mothers and expectant fathers when comparing verbal versus written-delivered formats. Eight of 10 questions in the PASQ5 were stable when assessing the items in a test–retest analysis in late pregnancy for expectant mothers and nine of 10 questions were stable for fathers. The SSAFP items showed high internal consistency (0.86) for expectant mothers and excellent internal consistency (0.94) for expectant fathers. Most SSAFP items (17 of 21 for expectant mothers and 18 of 22 for expectant fathers) were also stable in a test–retest scenario in late pregnancy. Both the PASQ5 and SSAFP are reliable tools and may be helpful for clinicians who aim to have a deeper dialogue about alcohol consumption during pregnancy. These tools may also be helpful for researchers aiming to better understand a person's changes in alcohol intake and/or their social support network. 相似文献
24.
To determine whether perturbations of haemostatic function and lipoprotein metabolism prevail long after preeclampsia and increase the risk of future coronary heart disease (CHD), we conducted a follow-up study in women with (cases, n = 25) or without (controls, n = 24) a history of preeclampsia. Blood samples were taken in the follicular and in the luteal phases of a menstrual cycle. Levels of blood pressure (BP) and proteinuria measured during the index pregnancy were included in the evaluation. Compared to control women who had undergone a normal pregnancy, the formerly preeclamptic patients had higher systolic (p <0.01) and diastolic (p <0.05) BPs and increased plasma levels of von Willebrand factor (vWF), fibrinogen, cholesterol, triglycerides and very low density lipoprotein (VLDL) (all p <0.05). The lipid, vWF, and fibrinogen levels were positively related to the degree of BP elevation but not to the degree of proteinuria during the index pregnancy. Except for the increase in vWF level, all biochemical perturbations were only present in the luteal but not in the follicular phase samples. In conclusion, persistent endothelial dysfunction with ensuing dysregulation of blood pressure, haemostatic perturbation and dyslipoproteinemia after preeclampsia may indicate a proneness to future CHD. 相似文献
25.
Screening for mutations in candidate genes for hypospadias 总被引:2,自引:0,他引:2
Nordenskjöld A Friedman E Tapper-Persson M Söderhäll C Leviav A Svensson J Anvret M 《Urological research》1999,27(1):49-55
Hypospadias, a condition with a frontally placed urethral orifice on the penis, is the most common malformation in males.
During fetal development several components are necessary for normal male genital development. Testosterone and dihydrotestosterone
act via the androgen receptor but a defective receptor function results in different degrees of genital malformations. Testosterone-5α-reductase
converts testosterone to dihydrotestosterone, which is crucial for normal differentiation, and a total lack of this enzyme
results, in syndromes with hypospadias. The Wilms' tumour 1 (WT1) gene is expressed in the fetal gonad and genital malformations
can occur due to WT1 gene mutations. These genes are therefore strong candidate genes for hypospadias. We have analysed 35
boys with hypopadias and one girl diagnosed as with complete androgen insensitivity syndrome, using exon by exon polymerace
chain reaction (PCR) amplification of the AR, WT1 and 5α-reductase genes and screened for point mutations and performed subsequent
DNA sequencing. No mutations in any of these genes were found in the 26 patients with isolated hypospadias. Two patients with
severe hypospadias with cryptorchidism were found to carry mutations in the androgen receptor gene. Also the girl with clinically
diagnosed complete androgen insensitivity was found to be homozygous for a splice mutation in the 5α-reductase gene. In summary,
mutations in the WT1, AR and 5α-reductase genes are not common causes of isolated hypospadias.
Received: 1 October 1997 / Accepted: 4 May 1998 相似文献
26.
ABSTRACT: Among critically ill patients, the diagnosis of bloodstream infection poses a major challenge. Current standard bacterial identification based on blood culture platforms is intrinsically time-consuming and slow. The continuous evolvement of molecular techniques has the potential of providing a faster, more sensitive and direct identification of causative pathogens without prior need for cultivation. This may ultimately impact clinical decision-making and antimicrobial treatment. This review summarises the currently available technologies, their strengths and limitations and the obstacles that have to be overcome in order to develop a satisfactory bedside point-of-care diagnostic tool for detection of bloodstream infection. 相似文献
27.
Margareta Johansson Ingegerd Hildingsson Jennifer Fenwick 《Sexual & Reproductive HealthCare》2013,4(1):35-36
The early postnatal period can be challenging for new fathers especially when their partner has experienced a caesarean section. The aim of this study was to describe men’s perceptions and feelings of staying with their partner and new baby in the context of having experienced a surgical birth. Thematic analysis was employed to analyse telephone interviews collected from 21 Swedish fathers who had experienced elective or emergency caesarean section. Being involved, receiving support and providing support were main reasons men considered it important they be facilitated to stay with their partners. Postnatal care should be oriented towards the whole family. 相似文献
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