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排序方式: 共有484条查询结果,搜索用时 15 毫秒
1.
A. Ian Smith Catherine A. Wallace Lain J. Clarke John W. Funder 《Journal of neuroendocrinology》1989,1(5):357-362
In the sheep, unlike many other species, a significant proportion (>25%) of immunoreactive β-endorphin in the anterior pituitary is post-translationally modified to opioid-inactive, α-N-acetylated forms. In a study to determine the precise molecular nature of α-N-acetylated β-endorphin immunoreactivity, we noted a striking difference in high-performance liquid chromatography profiles of anterior pituitary extracts between sheep killed on the farm, and age-, sex- and strain-matched slaughterhouse animals. These altered patterns of a-N-acetylated β-endorphin processing were reproduced in farm animals by chronic (≤ 4 days) treatment with the synthetic glucocorticoid dexamethasone; in contrast dexamethasone had no effect on a-N-acetylated β-endorphin processing in hypothalamo-pituitary disconnected sheep. These data suggest that (1) the change in processing is a stress response, mediated by prolonged glucocorticoid exposure, (2) this effect is central, rather than a direct effect on the pituitary, and (3) the relative abundance of various peptide sequences in slaughterhouse-derived material may not reflect their abundance under more physiological conditions. 相似文献
2.
3.
Claudia KY Lai 《BMC nursing》2007,6(1):5
Background
To date, the literature has provided an abundance of evidence on the adverse outcomes of restraint use on patients. Reportedly, nurses are often the personnel who initiate restraint use and attribute its use to ensuring the safety of the restrained and the others. A clinical trial using staff education and administrative input as the key components of a restraint reduction program was conducted in a rehabilitation setting to examine whether there were any significant differences in the prevalence of restraint use pre- and post-intervention. Subsequent to the implementation of the intervention program, focus group interviews were conducted to determine the perspective of the nursing staff on the use of restraints and their opinions of appropriate means to reduce their use. 相似文献4.
E. Lainé R. Couderc M. Roch-Arveiller M. P. Vasson J. P. Giroud D. Raichvarg 《Inflammation》1990,14(1):1-9
1-Acid glycoprotein (1-AGP), a naturally occurring human plasma protein and acute-phase reactant, was extracted by a two-step procedure from sera collected from four healthy men. Its activity was testedin vitro on human polymorphonuclear (PMN) functions (migration, aggregation, O
2
–
generation). 1,-AGP was not chemoattractant but inhibited the PMN response to the chemoattractant formylmethionyl-leucyl-phenylalanine without affecting spontaneous migration (Boyden and agarose methods of assessment). At concentrations between 0.15 and 0.45 mg/ml, 1AGP exerted an aggregating effect with a maximal effective concentration of 0.3 mg/ml. 1-AGP inhibited superoxide generation by PMNs stimulated either by opsonized zymosan or phorbol myristate acetate. This inhibition varied according to the intensity of the stimulation. At low stimulus concentrations, a dose-dependent inhibition of membrane-associated PMN responsiveness to soluble or particulate stimuli was observed. These findings suggest that 1-AGP may be able to prevent PMN activation in the course of inflammatory processesin vivo. 相似文献
5.
Estrogen receptor negative and progesterone receptor positive primary breast cancer: Pathological characteristics and clinical outcome 总被引:9,自引:0,他引:9
Agnès Bernoux Patricia de Cremoux Christine Lainé-Bidron Emmanuel C. Martin Bernard Asselain Henri Magdelénat 《Breast cancer research and treatment》1998,49(3):219-225
The expression of estrogen (ER) and progesterone (PgR) receptors was analyzed in a retrospective series of 3000 patients who had operable primary breast cancer. Patients were stratified according to ER and PgR status and the study was focused on the two groups (ER–PgR+ and ER–PgR–) of patients whose tumors contained low levels of ER (< 15 fmol/mg protein), regarding potential response to endocrine therapy. The comparison of clinical or histological characteristics between ER–PgR+ and ER–PgR– patients was analyzed as well as the disease-related death and survival. The mean follow-up was 86.3 months. Among the 529 ER–patients, 62 were PgR+ (12%), whereas 467 were PgR– (88%). The ER–PgR+ and ER–PgR– populations represented 2% and 15.6% of the overall population, respectively. In ER– tumors, the PgR status was significantly related to: age, menopausal status, tumor size, SBR grade, and histological type, but not to the type of surgical treatment or to lymph node involvement. ER–PgR+ tumors had smaller size (64% T1 vs 43%) (p=0.004) and were more frequently grade I (28% vs 12%) than ER–PgR– ones (p < 0.001). In addition, the patients with ER–PgR+ tumors were significantly younger (49.4 years vs 58.4 years; p < 0.0001), and were more frequently premenopausal (76% vs 36%; p < 0.001). The disease-free interval and the metastasis-free survival tended to be worse for ER–PgR– than for ER–PgR+ patients, but the difference was not statistically significant at 10 years. However, a small but significant difference in overall survival, in favor of the PgR+ group, was observed between the two groups during the first 5 years (p=0.03).We conclude that in combination with ER, PgR status defines a group of patients with clinical and biological specificity, which could be considered for specific endocrine therapy. 相似文献
7.
In order to enhance the immune efficacy of DNA vaccination, experiments were conducted to investigate the regulating effects of Bacillus Calmette-Guerin (BCG)-DNA as an adjuvant on immune responses of mice against foot-and-mouth disease (FMD), Aujeszky's disease (AID) and classical swine fever (CSF). BCG-DNA was purified from BCG by ion-exchange chromatography. Three DNA vaccines (pVSG, pVgD and pVE2) against the respective infection were constructed, and BCGDNA was coimmunized to mice by muscle injection. The results showed that titres of specific immunoglobulin (Ig)G to the vaccines mounted remarkably in the sera of the adjuvant covaccinated mice (P〈0.01). Antibody isotype IgG2a and IgG1 also increased, respectively, in mice coimmunized with BCG-DNA compared with those of the control groups (P〈0.01). Cellular immune cytokine interferon-gamma and cytotoxic T lymphocytes were detected in coimmunized BCG-DNA groups (P〈0. 05). Whereas interleukin-4, humoral immune cytokine, was not significant (P〉 0. 05). These results suggest that codelivery of BCG-DNA with DNA vaccines against FMD, AjD and CSF can enhance the induction of antigen-specific, especially, cell-mediated immunity. 相似文献
8.
Michelle Y L Tang Patrick H Y Chung Hau Y Chan Paul K H Tam Kenneth KY Wong 《Journal of pediatric surgery》2019,54(2):255-257
Objective
Helicobacter pylori infection is common among Asians. However, evidence in the recent years has demonstrated a decrease in the prevalence of H. pylori infection among children and adults worldwide. Our aim was to update its prevalence in symptomatic children in our locality in the recent 12?years and compared to the results of our previous review published in 2005.Methods
A retrospective review was carried out between 2005 and 2017. All children who presented with dyspepsia or gastrointestinal bleeding and underwent oesophagogastroduodenoscopy with antral biopsy taken were included. Patient demographics, endoscopic, or histological diagnosis and the H. pylori status were recorded.Main Results
A total of 602 patients were included. There was a statistically significant decreasing trend of H. pylori infection rate between 2005 and 2017 (p?=?0.003). The overall infection rate from this study was 12.8%, compared to 25.6% from our previous review. Overall failure of eradication with first-line antibiotic therapy has increased to 29.3% from 10% in our previous review.Conclusion
There was a decrease in the prevalence of H. pylori infection among symptomatic children for the recent 12?years, comparing to our previous data from 2005. We hypothesize that the reduction in prevalence of H. pylori infection among adults and the decrease in the practice of sharing chopsticks during meals have led to a decrease in transmission of the bacteria among family members in Hong Kong. However, the failure of eradication with first line treatment was higher, possibly due to the increase in antibiotics usage and resistance.Level of Evidence
III 相似文献9.
Pressure control inverse ratio ventilation as a method to reduce peak inspiratory pressure and provide adequate ventilation and oxygenation 总被引:2,自引:0,他引:2
Nineteen patients with ARDS or pneumonia who were ventilated with PcIRV on the Siemens-Elema Servo 900 C were retrospectively reviewed. The PcIRV reduced peak airway pressure, PEEP, increased Paw, and improved ventilation and oxygenation in these patients. When these patients were compared with themselves on prior conventional IPPV, all had a decrease in PIP, an increase in Paw and most had a decrease in VE, with no change in PaCO2 and an increase in PaO2. The increase in Paw may have contributed to this improved arterial oxygenation. High levels of PIP and PEEP during IPPV have been identified as risk factors in the development of barotrauma and residual parenchymal pulmonary damage. We propose that PcIRV allows for adequate ventilation and oxygenation with decreases in PIP, extrinsically added PEEP and inspired O2 concentration. This mode of ventilation may decrease the morbidity associated with IPPV utilizing high PIP and PEEP. 相似文献
10.