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大多数药物注射包部件(例如针头、注射器、活塞和瓶等)都要求采用某些形式的表面处理或润滑,以便改善其操作性和功能性。本文综述了硅烷化使用的材料和工艺,以及在其后对硅烷化制品的消毒和硅油的清除。  相似文献   
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OBJECTIVE: Garlic (Allium sativum) has been suggested to affect several cardiovascular risk factors. Its antiatherosclerotic properties are mainly attributed to allicin that is produced upon crushing of the garlic clove. Most previous studies used various garlic preparations in which allicin levels were not well defined. In the present study, we evaluated the effects of pure allicin on atherogenesis in experimental mouse models. METHODS AND RESULTS: Daily dietary supplement of allicin, 9 mg/kg body weight, reduced the atherosclerotic plaque area by 68.9 and 56.8% in apolipoprotein E-deficient and low-density lipoprotein (LDL) receptor knockout mice, respectively, as compared with control mice. LDL isolated from allicin-treated groups was more resistant to CuSO(4)-induced oxidation ex vivo than LDL isolated from control mice. Incubation of mouse plasma with (3)H-labeled allicin showed binding of allicin to lipoproteins. By using electron spin resonance, we demonstrated reduced Cu(2+) binding to LDL following allicin treatment. LDL treatment with allicin significantly inhibited both native LDL and oxidized LDL degradation by isolated mouse macrophages. CONCLUSIONS: By using a pure allicin preparation, we were able to show that allicin may affect atherosclerosis not only by acting as an antioxidant, but also by other mechanisms, such as lipoprotein modification and inhibition of LDL uptake and degradation by macrophages.  相似文献   
4.
1. In anaesthetized cats and dogs, local intra-arterial injection of noradrenaline and alpha, beta-methylene adenosine 5'-triphosphate (mATP) reduced both nasal arterial blood flow and nasal mucosal volume (a measure of capacitance vessel function). The responses to mATP were not modified by pretreatment with the adrenoceptor antagonists phentolamine and propranolol or the purinoceptor antagonist suramin. The vascular effects of noradrenaline were not altered by suramin, but were virtually abolished by adrenoceptor antagonists. 2. After adrenoceptor blockade, frequency-dependent reductions in nasal arterial blood flow with sympathetic nerve stimulation were reduced by 25 and 39% in cats and dogs, respectively; whereas the volume response was reduced by 56% in cats and 54% in dogs. The remaining non-adrenergic sympathetic nerve-evoked vascular responses were not influenced by suramin. 3. During desensitization to mATP induced by local intra-arterial infusion for 5 min, the remaining non-adrenergic nasal blood flow and volume responses to sympathetic nerve stimulation were reduced in the dog but not in the cat. 4. It is suggested that both adrenergic and non-adrenergic mechanisms are involved in the sympathetic control of the nasal mucosa vascular bed of both species. Since desensitization to mATP markedly reduces the remaining non-adrenergic nasal vasoconstriction evoked by sympathetic nerve stimulation in the dog, ATP is a possible sympathetic mediator in the nasal vascular bed in this species.  相似文献   
5.
Education has been related to various advantageous lifetime outcomes. Here, using longitudinal structural MRI data (4,422 observations), we tested the influential hypothesis that higher education translates into slower rates of brain aging. Cross-sectionally, education was modestly associated with regional cortical volume. However, despite marked mean atrophy in the cortex and hippocampus, education did not influence rates of change. The results were replicated across two independent samples. Our findings challenge the view that higher education slows brain aging.  相似文献   
6.
We examined the association between serum trace elements and clinical findings such as number of sensitive tender points, severity of fatigue and functional status in patients with fibromyalgia (FM). Thirty-two patients diagnosed as having FM according to the ACR 1990 criteria and 32 normal healthy controls (NHC) were included in this study. The demographic data, disease duration, number of tender points and accompanying symptoms (fatigue, sleep disorders, headache, paresthesia, irritable bowel syndrome, sicca symptoms, Raynaud's phenomena) of the patients were noted. Visual analog scale (10 cm) was implemented to estimate daily severity of pain and fatigue. Fibromyalgia impact questionnaire was used for functional assessment. Serum selenium (mug/dL) and serum zinc (mug/dL) levels were measured by atomic absorption spectrometer. Serum magnesium (mmol/L) level was measured by the original kits of Abbott Aeroset auto-analyzer. The mean age of patients in FM group and NHC were calculated as 42.9 (SD = 7.7) years and 41.3 (SD = 9.7) years, respectively. Serum levels of zinc (P = 0.001) and magnesium (P = 0.002) were significantly decreased by FM groups, whereas there was no considerable difference with selenium levels of both groups (P > 0.05). Association between serum zinc level and number of tender points (P = 0.008) and that between fatigue and magnesium level (P = 0.003) was found as meaningful. According to the results of this study, it was asserted that serum magnesium and zinc levels may play an important role in the pathophysiology of FM.  相似文献   
7.
The electrocardiogram (ECG) interpretation in patients with implantable cardioverter defibrillator (ICD) is often a puzzling problem. The difficulty of the device function evaluation further increases in the presence of unfamiliar timing cycles and additional functions. We present an interesting ECG with a special function of a Biotronik ICD devices called the thoracic impedance monitoring, and demonstrate its behavior in a patient with atrial fibrillation, pacing beats, ventricular ectopic beats, and couple of ventricular beats. This report shows unexceptional occurrence of tricky ECG finding in patient with Biotronik ICDs.  相似文献   
8.
The reliability, stability, and signal‐to‐noise ratio (SNR) of event‐related potentials (ERPs) were investigated in children, adolescents, younger adults, and older adults in performance monitoring tasks. P2, N2, P3, and P2‐N2 peak‐to‐peak amplitude showed high odd‐even split reliabilities in all age groups, ranging from.70 to.90. Multigroup analyses showed that test‐retest stabilities (across 2 weeks) of ERP amplitudes did not differ among the four age groups. In contrast, relative to adolescents and younger adults, SNRs were lower in children and older adults, with higher noise levels in children and lower signal power in older adults. We conclude that age differences in the SNR of stimulus‐locked ERPs can be successfully compensated by the averaging procedure with about 40 trials in the average. However, age differences in baseline noise and split‐half reliability should be considered when comparing age groups in single trial measures or time‐varying processes with ERPs.  相似文献   
9.
The individual alpha frequency (IAF) of the human EEG reflects systemic properties of the brain, is highly heritable, and relates to cognitive functioning. Not much is known about the modifiability of IAF by cognitive interventions. We report analyses of resting EEG from a large‐scale training study in which healthy younger (20–31 years, N = 30) and older (65–80 years, N = 28) adults practiced 12 cognitive tasks for ~100 1‐h sessions. EEG was recorded before and after the cognitive training intervention. In both age groups, IAF (and, in a control analysis, alpha amplitude) did not change, despite large gains in cognitive performance. As within‐session reliability and test‐retest stability were high for both age groups, imprecise measurements cannot account for the findings. In sum, IAF is highly stable in healthy adults up to 80 years, not easily modifiable by cognitive interventions alone, and thus qualifies as a stable neurophysiological trait marker.  相似文献   
10.
Objective:The aim of this study was to assess the quality of life (QoL) and psychological well-being in child and adolescent with disorders of sex development (DSD).Methods:Sixty-two cases, aged 2-18 years, who were followed by a multidisciplinary DSD team were included. All participants and their parents were requested the complete the Pediatric Quality Of Life Inventory (PedsQL) and the Strengths and Difficulties Questionnaire. The psychiatric diagnoses of the patients were evaluated according to Schedule for Affective Disorders and Schizophrenia for School-Age Children/Present and Lifetime Turkish Version.Results:There was no significant difference between the 46,XX DSD and 46,XY DSD groups for both child and parent in Total PedsQL score. In the subscale scores, the PedsQL Physical Functionality Score reported by children was significantly lower for the 46,XX DSD group than for the 46,XY DSD group (p=0.01). There was a psychiatric diagnosis in 25.8% of cases. The PedsQL School Functionality Score reported by children in the group with psychiatric diagnosis was significantly lower than the group without psychiatric diagnosis (p=0.018). In the group with psychiatric diagnosis, the PedsQL Total Score and the subscale scores (Emotional Functionality Score, Social Functionality Score, School Functionality) reported by parents were significantly lower than in parents of the group without psychiatric diagnosis.Conclusion:This study emphasized that psychiatric disorders in DSD patients negatively affect the QoL. Psychiatric support and counseling from a multidisciplinary team are very important for families affected by DSD.  相似文献   
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