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1.
Ultrasonication is very effective in dispersing alumina and barium titanate slurries. When optimum conditions are used, very short durations (2 to 3 min) are enough to achieve well-dispersed, stable suspensions.  相似文献   
2.
The relationship between aplastic anaemia (AA) and pregnancy remains uncertain. To assess whether an association between pregnancy and severe aplastic anaemia (SAA) exists, we compared the frequency of pregnancy in 35 young women with newly diagnosed SAA with the expected frequency in the general population. The observed pregnancy rate in the SAA group was 3-6%. This percentage approximates the expected pregnancy rate of 4.4% in the general population and is not compatible with a strong association between pregnancy and SAA.  相似文献   
3.
异步数字用户线路(ADSL)调制解调器由于同普通电话线相连,容易遭受电击。因此,必须施加恰当保护,以抵抗破坏性过压和压流的冲击。通晓保护标准、指导原则和器件,可以提高设计人员保护ADSL调制解调器的电话线及数据线免遭过压冲击的能力。如表1所示,标准的选择取决于设备类型、在网络中的位置和网络的地理区域。对于并联元器件,特别是具有急剧短路特性的器件,可以提供必要的雷电冲击保护功能。急剧短路器件的优点是可以高效地短接电话双绞线,消除过压,而且热量极小。在正常电压下,急剧短路器件保持开路状态。器件的电流处理能力取决于器…  相似文献   
4.
An enzyme immunoassay (EIA) was developed for the detection of hazelnut proteins in foods. This assay used inexpensive chicken egg yolk antibodies in a sandwich EIA format for the immunospecific capture and detection of hazelnut proteins present in a variety of different food matrices. The assay was able to detect less than 1 ppm of hazelnut protein in most of the foods tested and did not exhibit any appreciable cross-reactivity with other nuts or food matrices. This assay will be a useful tool for the food industry and regulatory agencies that wish to test foods for the presence of undeclared hazelnut allergens.  相似文献   
5.
Coagulation patterns of 19 newly-diagnosed acute promyelocytic leukemia (APL) patients with disseminated intravascular coagulation (DIC) at presentation were studied. Seventeen patients had hemorrhagic complications, of which four were fatal. Fatal hemorrhages were related with lower fibrinogen level and lower platelet count. DIC of the APL patients without infection was characterized by low fibrinogen and normal antithrombin III (ATIII) level. Thrombin-ATIII complex level was elevated in all patients examined. Patients with infection had higher fibrinogen levels than those without infection and some patients had reduced ATIII level. Ten remission inductions were tried with multidrug chemotherapy and seven with all-trans retinoic acid (ATRA). Complete remission was achieved in seven of ten inductions with chemotherapy and in all seven inductions with ATRA. Two patients treated with chemotherapy had fatal hemorrhage after starting therapy but none treated with ATRA.  相似文献   
6.
Pregnancy is a physiological state associated with significant changes in appetite, thermogenesis, and lipid metabolism, functions which are regulated in part by a hormone, leptin, secreted by adipocytes. Leptin has also been shown to have a role in reproduction, promoting centrally-regulated maturation of the reproductive system and signaling the presence of adequate maternal energy stores for fertility. Here we demonstrate that serum leptin levels are modulated during normal rat pregnancy with a 1.8-fold increase during pregnancy followed by a decrease just before parturition. Leptin receptor mRNA levels in the uterus are also regulated with an increase about 2.7-fold during this same period, whereas there is no change in other tissues examined. The results suggest that leptin may play a role during pregnancy, perhaps regulating energy utilization.  相似文献   
7.
The primary purpose of the present study was to determine whether multisystemic therapy (MST), an intensive, home-based psychotherapy, improved regimen adherence, metabolic control, and rates of hospitalization for diabetic ketoacidosis (DKA) among adolescents with chronically poorly controlled Type 1 diabetes 6 months after the completion of treatment. A randomized controlled trial was conducted with 127 adolescents and their families. Mean participant age was 13.2 years. Sixty-three percent of participants were African American, and 51% were female. Data were collected at baseline, treatment termination, and 6-month follow-up. Changes in glycated hemoglobin (HbA1c), frequency of blood glucose testing (BGT), and rate of DKA admissions were assessed. In intent-to-treat analyses, a main effect of MST on DKA admissions was found at both treatment termination and follow-up. Improvements in BGT were moderated by family composition; only 2-parent MST families maintained improvements at follow-up. Improvements in HbA1c for the MST group at treatment termination were lost at follow-up. Results show that intensive, home-based psychotherapy created stable reductions in serious lapses in adherence, as indexed by episodes of DKA, among youth with poorly controlled diabetes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Thirty adults' psychosocial maladjustment associated with a wildfire were systematically examined,one and a half months after a major wildfire destroyed 420 homes. The level of psychopathology was determined through the use of standardized assessment instruments, including the Diagnostic Interview Schedule and the Impact of Events Scale. Victims' individual responses were evaluated,relative to a comparison group from the same community matched for age, gender socioeconomic status, and fire insurance. Increased levels of posttraumatic stress,depression,and anxiety symptoms were reported significantly more often among victims versus non-victims. Also, females more often reported greater levels of psychological symptoms than males.Parent status and previous disaster experience had no differential impact on victims' reactions. Implications are discussed in light of existing findings in this area of research.  相似文献   
9.
This article reviews recently reported observations regarding the intracellular signal transduction mechanisms involved in the generation of phasic contractions occurring in myometrial tissue. The presence of cell surface receptors for classic uterotonic agonists (including oxytocin, norepinephrine, vasopressin, acetylcholine, and prostaglandins [PGs]) has been well described; all are seven-membrane-spanning, G protein-coupled receptors. Occupancy of these receptors, coupled through members of the Gq and/or Gi families of heterotrimeric G proteins, results in stimulation of the phospholipase C-beta (PLC-beta) isoforms. Nonclassic uterotonic agonists, such as growth factors and cytokines, also activate the phosphatidylinositol (PI)-signaling pathway, in this case through tyrosine kinase receptor-mediated activation of the phospholipase C-gamma (PLC-gamma) isoforms. Several recent reports have demonstrated that activation of the PI-signaling pathway in uterine myocytes results in the development of cytosolic calcium oscillation-like phenomena. These cytosolic calcium oscillations appear to arise from repetitive cycles of emptying and refill of the endoplasmic reticulum calcium stores along with the influx of extracellular calcium. Calcium release from the endoplasmic reticulum calcium stores appears to be mediated by the inositol trisphosphate-sensitive and the ryanodine-sensitive receptor/channels; isoforms for both the these receptor/channels have been shown to be expressed in myometrial tissue. In summary, receptor-mediated activation of the PI-signaling pathway and the generation of cytosolic calcium oscillations appear to produce intermittent calcium transients that result in the development and maintenance of phasic myometrial contractions.  相似文献   
10.
The purpose of the study was to assess whether therapist treatment fidelity was a predictor of treatment outcome in a randomized clinical trial of multisystemic therapy with 10- to 16-year-old youths with chronically poorly controlled Type I diabetes (N = 40). Treatment fidelity was assessed by objective ratings of therapy sessions and questionnaires completed by caregivers and by therapists. Relationships between fidelity measures were assessed. Structural equation modeling (SEM) was used to test whether high fidelity would lead to improved regimen adherence and to improved metabolic control outcomes via regimen adherence. Objective ratings of treatment fidelity were significantly related to therapist-reported but not to caregiver-reported treatment fidelity. SEM results supported a completely mediated pathway between treatment fidelity and metabolic control, with regimen adherence mediating the relationship. Results suggest that conducting complex behavioral interventions with a high degree of fidelity can improve treatment outcomes among youths with chronic illnesses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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