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51.
SYNOPSIS
The prophylactic anti-migraine effect of atenolol was compared to placebo in a multicentre study on 63 patients with classical and/or common migraine. The study design was double-blind cross-over and patients were given atenolol 100 mg o.d. or matching placebo during a study treatment period of 24 weeks. The effect of atenolol was significantly better than that of placebo: integrated headache values were reduced in 70% of the patients (p = 0.004) and the proportion of days with headache was reduced in 59% of the patients (p = 0.010). Few side effects were reported with both atenolol and placebo. This study shows atenolol to be safe and effective in the prophylactic treatment of migraine.  相似文献   
52.
Twelve apparently healthy male volunteers were maintained for 6 weeks on a fish diet, the haemostatic effects of which were determined as standardized skin bleeding times; thromboxane A2 formation in vivo in the bleeding time blood and in vitro in clotting venous blood; platelet aggregability; and platelet phospholipids. Within 1 week the fish diet changed the fatty acid composition of platelet membrane phospholipids, with increases in ω-3 and decreases in ω-6 fatty acids; decreased platelet aggregability by ADP and collagen; but the bleeding time was unchanged. Not until 6 weeks on the diet did the bleeding time increase (by 3 7%: P < 0-01) and it was still increased 3 weeks after the end of the diet, when the fatty acid composition of the platelets had returned to normal. The effect of the diet on decreased aggregability of platelets also failed to follow the changes in their fatty acid composition and in the bleeding time. Aggregation by ADP and by the highest dose of collagen was decreased throughout the diet and for several weeks thereafter, i.e. even when the fatty acid composition had reverted to the pre-dietary pattern and long after the normalization of the bleeding time. The diet caused no change in the in vivo appearance of thromboxane A2 in the bleeding time blood, contrasting with its effect in decreasing the in vitro formation of thromboxane A2 in clotting venous blood. These observations suggest that such fish diets do not delay haemostasis by diminishing the formation of thromboxane A2 locally nor directly by decreasing the aggregability of platelets or directly by the induced changes in their to-3 fatty acids.  相似文献   
53.
54.
Screening for mutations in candidate genes for hypospadias   总被引:2,自引:0,他引:2  
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   
55.
There is a lack of suitable human in vitro systems which can predict drug hepatotoxicity that in many cases involves inflammatory responses mediated by macrophages. In the present investigation we used an in vitro model based on human THP-1 cells to evaluate the inflammatory cytokine/chemokine activation properties of ximelagatran, a drug previously shown to cause elevation of liver transferases in a subset of patients. Treatment of the cells with ximelagatran caused an intracellular accumulation of the metabolites hydroxymelagatran and melagatran. A decreased viability and increased release of the pro-inflammatory cytokines and chemokines IL-8, VEGF and MCP-1 was seen. Ximelagatran exposure caused activation of ERK1/2 and JNK as evident from determination of the phosphorylation status. In accordance, the release of IL-8 was attenuated by inhibitors of the ERK- and JNK-pathways. It is concluded that human monocytes might constitute a valuable additional in vitro model for monitoring the basis for cytotoxic action of drugs.  相似文献   
56.

Background  

Obesity has primarily been addressed with interventions to promote weight loss and these have been largely unsuccessful. Primary prevention of obesity through support of weight maintenance may be a preferable strategy although to date this has not been the main focus of public health interventions. The aim of this study is to characterize who is not gaining weight during a 10 year period in Sweden.  相似文献   
57.
58.
In the present work we have investigated the cell proliferation pattern of flat serrated adenomas and flat tubular adenomas. For this purpose tissue sections from 23 consecutive flat serrated adenomas and 22 consecutive flat tubular adenomas of the colorcctal mucosa were challenged with MID1, a monoclonal antibody directed against a proliferation-related antigen. The results (including semi-quantitative studies) demonstrated that, whereas flat serrated adenomas had a high cell proliferation at the lower part of the crypts, flat tubular adenomas had a high cell proliferation in the upper part of the crypts. In serrated adenomas with invasive adenocarcinoma, high cell proliferation was demonstrated both at the lower portion of the crypts and in the subjacent submucosa. This suggests that the cells of the lower portion of the crypts in serrated adenomas are truely neoplastic, with the capacity to evolve into invasive growth. The difference in cell proliferation betweeen the two types of flat lesions reported here is a new argument in favor of the classification of flat serrated adenomas as a novel and independent type of neoplastic change of the colorectal mucosa.  相似文献   
59.
Grande M  Carlström K  Stege R  Pousette A  Faxén M 《European urology》2002,41(5):568-72; discussion 573-4
OBJECTIVE: To study effects of estrogens on endothelin-1 (ET-1) mRNA expression in the androgen-sensitive LNCaP-FGC cell line and its androgen-resistant derivative LNCaP-r. Further, if effects of estrone sulfate (E1S) are mediated via conversion to estradiol-17beta (E2). Estrogens have been shown to down-regulate ET-1, a mediator of the osteoblastic response of bone to metastatic prostate cancer.METHODS: Cells were grown in steroid-depleted medium and incubated for 2-4 and 48 hours with 0, 1, 10, and 100 nM of either E1S or E2. mRNA levels were measured with an RT-PCR technique. Estrogen metabolism by LNCaP-FGC cells was studied by incubation with estrone (E1) and E1S at the same conditions, followed by determination of E1 and E2.RESULTS: ET-1 mRNA expression in LNCaP-FGC cells was significantly suppressed by E2 and E1S following incubation for 2-4h but after 48 h only by E2 at 1 and 10nM and in LNCaP-r cells only by E2 at 100 nM following 2-4h of incubation. ET-1 mRNA expression was significantly higher in untreated LNCaP-r than in untreated LNCaP-FGC cells. E1 was efficiently transformed into E2 by LNCaP-FGC cells but very little to E1 and no E2 was formed from E1S.CONCLUSION: ET-1 mRNA expression in LNCaP-FGC can be inhibited by E2, but also by its prehormone E1S. The lack of formation of E2 from E1S suggests a mode of action not related to classical steroid receptors. The higher level of ET-1 mRNA expression found in LNCaP-r cells may reflect the capability of a hormone refractory tumor to maintain activity on its own, independently of known regulatory mechanisms such as sex steroids.  相似文献   
60.
Survival of transplanted human corneal stem cells. Case report   总被引:4,自引:0,他引:4  
PURPOSE: To report a case history involving long-term survival of transplanted human corneal stem cells. METHODS: A male patient with severe bilateral chemical burns received six corneal transplants, all of which failed. He subsequently received combined corneal transplants and stem cell transplants, which have remained clear for 3 and 4 years respectively. One of the donors was female. We studied the gender of the epithelial cells of the cheek of the patient and of the two grafts using fixation and fluorescent in situ hybridization (FISH) analyses. RESULTS: In the graft from the female donor, 30% of the epithelial cells were of female origin. All the epithelial cells from the cheek and the other graft were of male origin. CONCLUSION: This case demonstrates that transplanted human corneal stem cells can survive and replicate in the long-term (3 years) without systemic immunosuppression. The case also indicates that a minority (30%) of healthy transplanted epithelial cells is enough to present a clear graft with a clinically healthy ocular surface.  相似文献   
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