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排序方式: 共有778条查询结果,搜索用时 15 毫秒
41.
Iaccarino G Barbato E Cipolleta E Esposito A Fiorillo A Koch WJ Trimarco B 《Hypertension》2001,37(2):255-260
Elevated circulating angiotensin (Ang) II levels, dietary sodium, and sympathetic stimulation are recurrent themes of hypertension research, but their in vivo interaction in physiologically meaningful doses has not been adequately investigated. In this study, the interaction of a subpressor dose of Ang II (50 ng. kg(-1). min(-1) SC), 2% NaCl diet, and sympathetic stimulation in the form of overnight cold exposure was investigated in the development of hypertension and of structural vascular changes in male Sprague-Dawley rats. There were 8 experimental groups: sham operation and treatment (control), Ang II, 2% NaCl diet, cold exposure (5 degrees C), Ang II plus 2% NaCl diet, Ang II plus cold exposure, cold exposure plus 2% NaCl diet, and Ang II plus 2% NaCl diet plus cold exposure (triple treatment). For each group, the duration of treatment was 12 weeks. Morphometric measurements of maximally dilated, in situ fixed, second-order (250 to 320 microm OD), intermediate-size (100 to 150 microm OD), and small (50 to 100 microm OD) mesenteric arteries were performed, and wall-to-lumen ratios (W/L) were calculated. During the 12-week study, the blood pressure (BP) load (the area under the systolic BP curve) of rats receiving the combined treatment of Ang II and 2% NaCl diet was increased (P:<0.05), and that of rats receiving the combined treatment of cold exposure and 2% NaCl diet was decreased (P:<0.05); there were no BP changes in the remaining groups of rats. The most pronounced changes among groups occurred in W/L of small resistance arteries. The W/L of small arteries increased in Ang II-treated (P:<0.01) and in cold-stressed rats (P:<0.01). The effect of Ang II was potentiated by the addition of a 2% NaCl diet. In contrast, the addition of 2% NaCl diet to cold stress reduced the W/L of small arteries (P:<0.01). No other positive or negative synergism occurred among groups, including the rats receiving triple treatment. The findings confirm the potentiation of the hypertensinogenic and vascular trophic effects of Ang II by a high-sodium diet but do not provide evidence for synergism between Ang II and sympathetic stimulation. The finding of hypotension and reduced W/L of small resistance arteries in rats receiving the combined treatment of cold stress and high-sodium diet is unique because there are few known nonpharmacological vascular "hypotrophic" stimuli. The ultimate test of the hypertensinogenic potential of pressor stimuli alone or in combination is their long-term administration in physiologically meaningful doses to experimental animals. 相似文献
42.
Chronic interstitial lung disease (ILD) is rare in children, but is clinically relevant because of its high morbidity and mortality rates. Several aetiological agents may have a role in this disease and various aetiopathogenic forms have been described, although they share a characteristic evolution towards pulmonary fibrosis. The aetiology sometimes remains unknown, in which case we speak of idiopathic interstitial pneumonia (IIP). Diagnosis relies on non-invasive methods (clinical history, respiratory function tests, chest X-ray and high-resolution CT scan) and invasive techniques (bronchoalveolar lavage, transbronchial biopsy, video-assisted thoracoscopic biopsy and open lung biopsy); the latter are used when the former fail to identify an aetiological agent. The gold standard for the diagnosis is lung biopsy, however, which also enables the classification of the idiopathic forms, in particular (usual interstitial pneumonia, desquamative interstitial pneumonia, non-specific interstitial pneumonia, and so on). In ILD, the most common therapeutic approaches involve the use of oral steroids and hydroxychloroquine sulphate for its anti-inflammatory and antifibrotic effect. The prognosis is often poor. 相似文献
43.
The aim of this study was to evaluate the effectiveness of lactational amenorrhoea and to determine the relationship between extended breastfeeding and the return of fertility. Breastfeeding pattern, basal body temperature, cervical mucus, salivary ferning, vaginal blood discharge, frequency of sexual intercourse, and the presence of ovulation in the first cycle after the resumption of menses with ultrasonography were evaluated in 40 women. All subjects completed the study with only one case of incomplete breastfeeding. No pregnancies were observed. The mean number of feeding sessions and mean interval between sessions decreased significantly (p <0.01) during the first six months postpartum (7.5 +/- 1.3 after 60 days postpartum vs. 5.7 +/- 2.1 after 180 days, and 3.6 +/- 0.8 vs. 5.1 +/- 0.9, respectively). Eight women (20%) menstruated before weaning, but none had an adequate thermal shift, while 32 (80%) had their first vaginal bleeding after weaning with 12 (37.5%) registering an adequate thermal shift. Both basal body temperature and salivary ferning proved to be suggestive of ovarian activity, while mucus characteristics were not reliable in identifying fertile periods. Our study showed that breastfeeding associated with lactational amenorrhoea proved to be a good method of postpartum fertility control. Since the importance of supplementation is still debated, it is recommended that a "complete" breastfeeding program be used. 相似文献
44.
The coeliac iceberg in Italy. A multicentre antigliadin antibodies screening for coeliac disease in school-age subjects 总被引:8,自引:0,他引:8
C Catassi E Fabiani IM Rätsch GV Coppa PL Giorgi R Pierdomenico S Alessandrini G Iwanejko R Domenici E Mei A Miano M Marani G Bottaro M Spina M Dotti A Montanelli M Barbato F Viola R Lazzari M Vallini G Guariso M Plebani F Cataldo G Traverso C Ughi G Chiaravalloti M Baldassarre P Scarcella F Bascietto L Ceglie A Valenti P Paolucci M Caradonna E Bravi A Ventura 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(S412):29-35
Background : Recent studies suggest that coeliac disease (CD) is one of the commonest, life-long disorders in Italy. The aims of this multicentre work were: (a) to establish the prevalence of CD on a nationwide basis; and (b) to characterize the CD clinical spectrum in Italy. Patients and methods : Fifteen centres screened 17201 students aged 6–15 years (68.6% of the eligible population) by the combined determination of serum IgG- and IgA-antigliadin antibody (AGA) test; 1289 (7.5%) were IgG and/or IgA-AGA positive and were recalled for the second-level investigation; 111 of them met the criteria for the intestinal biopsy: IgA-AGA positivity and/or AEA positivity or IgG-AGA positivity plus serum IgA deficiency. Results : Intestinal biopsy was performed on 98 of the 111 subjects. CD was diagnosed in 82 subjects (75 biopsy proven, 7 not biopsied but with associated AGA and AEA positivity). Most of the screening-detected coeliac patients showed low-grade intensity illness often associated with decreased psychophysical well-being. There were two AEA negative cases with associated CD and IgA deficiency. The prevalence of undiagnosed CD was 4.77 × 1000 (95% CI 3.79–5.91), 1 in 210 subjects. The overall prevalence of CD, including known CD cases, was 5.44 × 1000 (95% CI 4.57–6.44), 1 in 184 subjects. The ratio of known to undiagnosed CD cases was 1 in 7. Conclusions : These findings confirm that, in Italy, CD is one of the most common chronic disorders showing a wide and heterogeneous clinical spectrum. Most CD cases remain undiagnosed unless actively searched. 相似文献
45.
The acrocephalosyndactylia III is a syndrome, which follows an autosomal dominant mode of inheritance, characterized by premature fusion of the cranial sutures in association with mild cutaneous syndactyly. The authors describe two cases recently come to their observation and point out the usefulness of the imaging diagnostics (CT, MRI) in finding anomalies specific of this affection. 相似文献
46.
Dolfini E Roncoroni L Elli L Fumagalli C Colombo R Ramponi S Forlani F Bardella MT 《World journal of gastroenterology : WJG》2005,11(48):7597-7601
AIM: To evaluate the interplay between gliadin and LoVo cells and the direct effect of gliadin on cytoskeletal patterns. METHODS: We treated LoVo multicellular spheroids with digested bread wheat gliadin in order to investigate their morphology and ultrastructure (by means of light microscopy and scanning electron microscopy), and the effect of gliadin on actin (phalloidin fluorescence) and the tight-junction protein occludin and zonula occluden-1. RESULTS: The treated spheroids had deep holes and surface blebs, whereas the controls were smoothly surfaced ovoids. The incubation of LoVo spheroids with gliadin decreased the number of intracellular actin filaments, impaired and disassembled the integrity of the tight-junction system. CONCLUSION: Our data obtained from an "in vivo-like" polarized culture system confirm the direct noxious effect of gliadin on the cytoskeleton and tight junctions of epithelial cells. Unlike two-dimensional cell culture systems, the use of multicellular spheroids seems to provide a suitable model for studying cell-cell interactions. 相似文献
47.
48.
Parabiaghi A Barbato A D'Avanzo B Erlicher A Lora A 《The Australian and New Zealand journal of psychiatry》2005,39(8):719-725
OBJECTIVE: Many authors recommended that reliable and clinically significant change (RCSC) should be calculated when reporting results of interventions. To test the reliability of the Health of the Nation Outcome Scales (HoNOS) in identifying RCSC, we applied the Jacobson and Truax model to two HoNOS assessments in a large group of people evaluated in 10 community mental health services in Lombardy, Italy, in 2000. METHOD: The HoNOS was administered to 9817 patients; of these, 4759 (48%) were re-assessed. Reliable change (RC) was calculated using Cronbach's alpha (alpha), as a parameter of the reliability of the measure. Clinical significance cut-offs were calculated using a classification of severity based on HoNOS items. RESULTS: In the whole sample, the clinical improvement cut-off was 11 and the remission cut-off was 5. Considering the severe patients, the clinical improvement cut-off was 12. The RC index calculated on the whole group and on the subgroup of severe patients indicated that eight-point and seven-point changes, respectively, were needed to be confident that a real change had occurred. Longitudinal changes were depicted on two-dimensional graphs as examples of reporting RCSC on HoNOS total scores in a routine data collection: 91.6% of the whole sample (4361) was stable, 5.6% (269) improved and 1.8% (129) worsened. CONCLUSION: Our study proposes a methodological framework for computing RCSC normative data on a widely used outcome scale and for identifying different degrees of clinical change. 相似文献
49.
Perna AF Ingrosso D Satta E Lombardi C Acanfora F De Santo NG 《Current opinion in clinical nutrition and metabolic care》2004,7(1):53-57
PURPOSE OF REVIEW: This review focuses on recent findings (June 2002-July 2003) on the topic of homocysteine, a sulfur amino acid associated with cardiovascular disease, and its metabolism in renal failure, a condition with a high prevalence of both hyperhomocysteinemia and cardiovascular disease. RECENT FINDINGS: A large meta-analysis of prospective studies in the general population established that hyperhomocysteinemia is a risk factor for cardiovascular disease. The results of intervention trials, once available, will also have to be tested in a meta-analysis, because of predicted problems with their statistical power. In kidney patients, intervention trials, still in the recruiting stage, target transplant patients, because of their unique characteristics related to folate responsiveness. As for the cause of hyperhomocysteinemia, new findings show that in humans, renal metabolic extraction depends on renal plasma flow in the post-absorptive state. Folate absorption or interconversion seems not to be affected. Riboflavin is a determinant of plasma homocysteine levels in uraemia. The consequences of hyperhomocysteinemia in uraemia are DNA hypomethylation and altered gene expression. SUMMARY: The causes of hyperhomocysteinemia in renal failure are still not clear. However, the possibilities include defective renal or extrarenal metabolism as a result of uraemic toxicity. Renal plasma flow is important in homocysteine renal metabolism. Among the consequences of hyperhomocysteinemia in renal failure are impaired protein and DNA methylation, with an alteration in the allelic expression of genes regulated through methylation. Intervention trials are under way to test whether hyperhomocysteinemia is causally related to cardiovascular disease in this patient population. 相似文献
50.
De Lorenzi E Giorgetti S Grossi S Merlini G Caccialanza G Bellotti V 《Current medicinal chemistry》2004,11(8):1065-1084
The group of diseases caused by abnormalities of the process of protein folding and unfolding is rapidly growing and includes diseases caused by loss of function as well as diseases caused by gain of function of misfolded proteins. Amyloidoses are caused by gain of function of certain proteins that lose their native structure and self-assemble into toxic insoluble, extracellular fibrils. This process requires the contribution of multiple factors of which only a few are established, namely the conformational modification of the amyloidogenic protein, protein's post-translational modifications and the co-deposition of glycosaminoglicans and of serum amyloid P component. In parallel with the exponential growth of biochemical data regarding the key events of the fibrillogenic process, several reports have shown that small molecules, through the interaction with either the amyloidogenic proteins or with the common constituents, can modify the kinetics of formation of amyloid fibrils or can facilitate amyloid reabsorption. These small molecules can be classified on the basis of their protein target and mechanism of action, according to the following properties. 1) molecules that stabilize the amyloidogenic protein precursor 2) molecules that prevent fibrillogenesis by acting on partially folded intermediates of the folding process as well as on low molecular weight oligomers populating the initial phase of fibril formation 3) molecules that interact with mature amyloid fibrils and weaken their structural stability 4) molecules that displace fundamental co-factors of the amyloid deposits like glycosaminoglycans and serum amyloid P component and favor the dissolution of the fibrillar aggregate. 相似文献