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排序方式: 共有499条查询结果,搜索用时 24 毫秒
61.
62.
Background: The benefits of probiotics to the pediatric Helicobacter pylori infection remain uncertain. We tested whether the H. pylori‐infected children have an altered gut microflora, and whether probiotics‐containing yogurt can restore such change and improve their H. pylori‐related immune cascades. Methods: We prospectively included 38 children with H. pylori infection confirmed by a positive 13C‐urea breath test (UBT) and 38 age‐ and sex‐matched noninfected controls. All of them have provided the serum and stool samples before and after 4‐week ingestion of probiotics‐containing yogurt. The serum samples were tested for the TNF‐α, IL‐10, IL‐6, immunoglobulin (Ig) A, G, E, pepsinogens I and II levels. The stool samples were tested for the colony counts of Bifidobacterium spp. and Escherichia coli. The follow‐up UBT indirectly assessed the H. pylori loads after yogurt usage. Results: The H. pylori‐infected children had lower fecal Bifidobacterium spp. count (p = .009), Bifidobacterium spp./E. coli ratio (p = .04), serum IgA titer (p = .04), and pepsinogens I/II ratio (p < .001) than in controls. In the H. pylori‐infected children, 4‐week yogurt ingestion reduced the IL‐6 level (p < .01) and H. pylori loads (p = .046), but elevated the serum IgA and pepsinogen II levels (p < .001). Moreover, yogurt ingestion can improve the childhood fecal Bifidobacterium spp./E. coli ratio (p = .03). Conclusions: The H. pylori‐infected children have a lower Bifidobacterium microflora in gut. The probiotics‐containing yogurt can offer benefits to restore Bifidobacterium spp./E. coli ratio in children and suppress the H. pylori load with increment of serum IgA but with reduction in IL‐6 in H. pylori‐infected children. 相似文献
63.
HM Su WC Tsai TH Lin PC Hsu WH Lee MY Lin SC Chen CS Lee WC Voon WT Lai SH Sheu 《PloS one》2012,7(8):e42815
The P wave parameters measured by 12-lead electrocardiogram (ECG) are commonly used as noninvasive tools to assess for left atrial enlargement. There are limited studies to evaluate whether P wave parameters are independently associated with decline in renal function. Accordingly, the aim of this study is to assess whether P wave parameters are independently associated with progression to renal end point of ≥25% decline in estimated glomerular filtration rate (eGFR). This longitudinal study included 166 patients. The renal end point was defined as ≥25% decline in eGFR. We measured two ECG P wave parameters corrected by heart rate, i.e. corrected P wave dispersion (PWdisperC) and corrected P wave maximum duration (PWdurMaxC). Heart function and structure were measured from echocardiography. Clinical data, P wave parameters, and echocardiographic measurements were compared and analyzed. Forty-three patients (25.9%) reached renal end point. Kaplan-Meier curves for renal end point-free survival showed PWdisperC > median (63.0 ms) (log-rank P = 0.004) and PWdurMaxC > median (117.9 ms) (log-rank P<0.001) were associated with progression to renal end point. Multivariate forward Cox-regression analysis identified increased PWdisperC (hazard ratio [HR], 1.024; P = 0.001) and PWdurMaxC (HR, 1.029; P = 0.001) were independently associated with progression to renal end point. Our results demonstrate that increased PWdisperC and PWdurMaxC were independently associated with progression to renal end point. Screening patients by means of PWdisperC and PWdurMaxC on 12 lead ECG may help identify a high risk group of rapid renal function decline. 相似文献
64.
J S Sun K M Shieh H C Chiang S Y Sheu Y S Hang F J Lu Y H Tsuang 《Free radical biology & medicine》1999,26(9-10):1100-1107
Benzophenone is an ultraviolet (UV)-absorbing agent that has been used in industry and medicine for more than 30 years. Consumers of cosmetics and sunscreens containing UV-absorbers are exposed to benzophenones on a daily basis, owing to the widespread use of these compounds. However, the efficacy of these compounds as scavengers of oxidative stress is still not well established. In the present study, we investigate the antioxidative capacity of six sunscreen benzophenone compounds. A primary myoblast culture was mixed in vitro with 100 microM menadione. The cytotoxic effect by menadione-induced oxidative stress was monitored by the lucigenin- or luminol-amplified chemiluminescence, methylthiotetrazole (MTT) assay, and the antioxidative effects of various benzophenone compounds were evaluated. The results showed that the addition of menadione can induce oxidative stress on myoblasts by superoxide and hydrogen peroxide production, which can be eradicated by superoxide dismutase (SOD) and catalase, respectively, in a dose-dependent mode. The catalase has a protective effect on the cytotoxicity induced by menadione as measured by the MTT assay, while the SOD does not. The selected benzophenones also have a significant scavenging effect on the menadione-induced cell death on the myoblasts. The ortho-dihydroxyl structure and other hydroxy groups in the same ring have a stronger scavenging effect on the superoxide anion on myoblasts; thus, a stable penoxy radical may be formed. The mechanism of this effect remains to be clarified. 相似文献
65.
The altered plasma statuses of selected minerals (Ca, Mg, Cu, Zn) have been noted in a cluster of insulin resistance syndromes, including hypertension and diabetes mellitus. The differences in plasma values of these minerals in hypertensive men with and without insulin resistance, as evaluated by an insulin suppression test, were investigated. The results showed that the plasma values of determined minerals at fasting, 2 h after an oral glucose challenge, and after the insulin suppression test did not markedly differ between hypertensive subjects with and without insulin resistance. However, hypertensive subjects had significantly lower plasma Ca values at fasting and 2h after an oral glucose load, and higher fasting plasma Zn values, than normotensive controls. Hypertensive subjects also had higher steady-state plasma glucose values, higher Zn and lower Mg and Cu values after the insulin suppression test, when compared with controls. The present study suggests that altered plasma status of selected minerals in hypertension cannot be totally ascribed to the coexhibition of insulin resistance. 相似文献
66.
67.
Summary Temperature-sensitive nitrogen fixation mutants of Azotobacter vinelandii were obtained by nitrosoguanidine mutagenesis and penicillin selection. The mutants were unable to grow on N2 at 39° but grew normally at 30° on N2 and at both temperatures in the presence of metabolizable nitrogen compounds. Growth experiments and assays of whole cells for nitrogenase activity separated the mutants into two classes: 1. mutants in which the nitrogenase activity present in cells grown at 30° was unaffected by a shift to 39°, and 2. mutants which lost their nitrogen fixation activity after such a temperature shift. Assays of cell-free extracts of the second class of mutants showed that in all cases tested the enzymatic activity of the nitrogenase complex itself was not affected by the mutation. These mutants might therefore contain some other temperature-sensitive proteins specifically involved in nitrogen fixation. 相似文献
68.
69.
Whether leptin, a product of the ob gene, can be stimulated by glucocorticoid administration has been an issue of controversy. We investigated the effect of intravenous administration of methylprednisolone (500 mg/day x 3 days) on plasma levels of leptin in 16 patients (female/male = 11/5) with Graves' hyperthyroidism and active ophthalmopathy who received pulse therapy. Significant elevation of plasma leptin levels started at the eighth hour (13.9+/-1.8 ng/mL, p=0.042) and lasted until the 72nd hour (21.2+/-5.0 ng/mL, p=0.009), as compared with basal levels (8.8+/-1.2 ng/mL). When methylprednisolone was replaced with oral prednisolone (10 mg three times per day x 2 weeks), no difference in plasma leptin levels was noted compared with basal measurement. Under methylprednisolone administration, a significant suppression of tumor necrosis factor-alpha began at the 24th hour (8.1+/-1.3 pg/mL, p=0.004) and lasted until the 48th hour (8.1+/-1.0 pg/mL, p=0.008), as compared with basal measurement (12.5+/-1.5 pg/mL). Compared with basal levels (93+/-2 mg/dL), significant elevation in the plasma glucose level started at the third hour (135+/-10 mg/dL, p=0.000) and lasted until the 72nd hour (110+/-4 mg/dL, p=0.019). The timing of serum insulin elevation approximated that of plasma glucose (3 hours: 14+/-3 microU/mL, p=0.006) and lasted until the end of prednisolone administration (2 weeks: 12+/-2 microU/mL, p=0.044), when compared with basal levels (14+/-3 microU/mL). We concluded that the parental administration of pharmacological doses of methylprednisolone to patients with Graves' hyperthyroidism could acutely raise their plasma level of leptin. 相似文献
70.
Wen-Chiuan Tsai Jong-Shiaw Jin Wei-Kuo Chang De-Chuan Chan Ming-Kung Yeh Shiou-Chih Cherng Li-Fan Lin Lai-Fa Sheu You-Chen Chao 《The journal of histochemistry and cytochemistry》2007,55(9):955-962
Cortactin and fascin-1 are important factors in tumor progression. We tested the hypothesis that cortactin and fascin-1 expression correlates with clinicopathological parameters of gastric adenocarcinoma. Immunohistochemical analysis of cortactin and fascin-1 was done using tissue microarrays of 100 surgical specimens, including 20 well-differentiated, 20 moderately differentiated, and 60 poorly differentiated gastric adenocarcinomas. Among the 20 well-differentiated gastric adenocarcinomas, 15 cases (75%) showed negative or weak staining (1+); 5 cases (25%) had moderate (2+) or strong (3+) cortactin expression. Among the 60 poorly differentiated gastric adenocarcinomas, more than three-quarters of the cases (76.7%) had moderate or strong cortactin expression; 14 cases (23.3%) had weak staining. Of 20 well-differentiated gastric adenocarcinoma cases, 14 (70%) showed negative or weak staining of fascin-1, whereas nearly one-third (30%) had moderate or strong expression. Among the 60 poorly differentiated gastric adenocarcinomas, 32 (53.3%) exhibited moderate or strong fascin-1 expression; fewer than half of the cases showed negative or weak staining. Higher intensity of cortactin and fascin-1 staining correlated directly with more-advanced cancer stages (TNM) and inversely with survival rates. Our findings suggest the possibility that pharmacological inhibitors of cortactin and fascin-1 activity may slow down tumor progression and prolong survival time in patients with gastric adenocarcinomas. 相似文献