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1.
朱宝亭  褚云鸿 《药学学报》1990,25(7):490-493
本文观察了[D-Ala6,Pro9-Ethylamide10]-LHRH(LHRH-A)对孕中期大鼠的抗妊娠作用。结果显示:在孕9~11d sc 200μg/d LHRH-A,血浆孕酮水平自第二次给药后明显下降(P<0.05),给药大鼠均流产终止妊娠;LHRH-A的抗妊娠作用可被醋酸甲地孕酮所拮抗;LHRH-A对体外培养的假孕大鼠和孕d 9大鼠黄体细胞分泌孕酮有明显的直接抑制作用。  相似文献   
2.
The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD.  相似文献   
3.
Parental and professional responses to questionnaires evaluating a paediatric disability service are reported and the viability of auditing structural, process, and outcome aspects of clinical practice are discussed. Expectations of waiting time to first appointment (met for only 52% of consumers) illustrate structural issues. Process issues are reflected in consumer reactions to outreach work (for example, 94% of parents and 84% of professionals found this supportive). Outcome measures such as consumer satisfaction with the service (76% of consumers reported being 'very satisfied' and 20% 'fairly satisfied') suggest that service aims are being met. Good concurrence of service aims with consumer needs is indicated by parental reasons for referral (for example, 75% for diagnostic help, 73% for a better understanding of the disorder, 88% for practical help), referrers' reasons (for example, 55% for a second diagnostic opinion, 45% due to lack of local expertise), and reports from most other professionals involved with the case that a similar service was not provided locally.  相似文献   
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总粉尘浓度转换为呼吸性粉尘浓度的两种方法学研究   总被引:2,自引:1,他引:1  
目的探讨流行病学研究中历史性总粉尘浓度转换成呼吸性粉尘浓度的理论方法。方法采用两种方法:一种通过体积直接计算;另一种用HatchChoate方程计算,推导出计数百分比和计量百分比的转换关系。结果得到总粉尘浓度与呼吸性粉尘浓度的理论转换系数,其中,用HatchChoate方程计算结果偏低。结论体积直接计算法更适用。  相似文献   
6.
Although older adults typically underutilize mental health services, problems associated with dementing illnesses, chronic medical illnesses, affective disorders, social isolation, and multiple medication use, among other phenomena, have increased referrals of the elderly to psychiatric emergency services. The present study reviewed characteristics of elderly adults referred to a psychiatric emergency outreach/screening service. Of all individuals for whom a referral was made, 24% were aged 60 or older. Among those older adults referred, 63% were seen by screening service personnel; 37% did not meet screening criteria or voluntarily sought mental health services. Diagnoses of individuals evaluated included dementia (27%), affective disorders (27%), schizophrenia (16%), psychosis (12%), alcohol abuse (7), and diagnosis deferred (11%). Findings highlight the limited options available for mental health care of the aged.  相似文献   
7.
AIMS: To study the effect of prone and supine sleep on infant behaviour, peripheral skin temperature, and cardiorespiratory parameters to aid understanding of why prone sleeping is associated with an increased risk of sudden infant death syndrome. METHODS: Of 33 enrolled infants, 32 were studied at 2.5 and 28 at 5 months of age. A computer aided multichannel system was used for polysomnographic recordings. Behaviour was charted separately. RESULTS: Prone REM (active) sleep was associated with lower frequencies of short arousals, body movements and sighs, and a shorter duration of apnoeas than supine REM sleep at both ages. At 2.5 months there were less frequent episodes of periodic breathing during prone sleep in non-REM (quiet) and REM sleep. Heart rate and peripheral skin temperature were higher in the prone position during both sleep states at both ages. CONCLUSIONS: The observation of decreased variation in behaviour and respiratory pattern, increased heart rate, and increased peripheral skin temperature during prone compared with supine sleep may indicate that young infants are less able to maintain adequate respiratory and metabolic homoeostasis during prone sleep.  相似文献   
8.
Many of the common molecular alterations associated with prostate cancer progression involve genes known to regulate cell death susceptibility. The significance of these molecular events is discussed in the context of developing and implementing new strategies designed to restore cell death susceptibility in prostate cancer cells and overcome therapeutic resistance.  相似文献   
9.
Purpose: To review literature specific to the use of AAC with adults who have severe aphasia. Method: The authors reviewed studies involving AAC interventions for adults with severe aphasia. Results: Published data support the use of aided and unaided AAC with adults with severe aphasia in controlled treatment contexts. Reported gains in communication typically have not generalized to everyday settings. Conclusions: The application of AAC with persons with severe aphasia must address factors potentially limiting treatment success outside of training environments.  相似文献   
10.
Heat shock protein (HSP) 70 and HSP90 are released by primary human acute myeloid leukemia (AML) cells during stress-induced spontaneous in vitro apoptosis. The AML cells also show constitutive release of several cytokines and the systemic serum levels of several soluble mediators are altered in patients with untreated AML. In the present study, we have investigated serum levels of HSP70/HSP90 and the serum cytokine profiles of patients with untreated AML and patients receiving AML-stabilizing palliative treatment based on all-trans retinoic acid (ATRA) plus valproic acid. Patients with untreated AML showed increased HSP90 levels and a distinct serum cytokine profile when compared with healthy controls, and low pre-therapy HSP90 levels were associated with a prolonged survival during treatment with ATRA + valproic acid + theophyllin. Hierarchical cluster analysis showed a close association between HSP70, HSP90, IL-1 receptor antagonist (IL-1ra), and hepatocyte growth factor (HGF) levels. Furthermore, disease-stabilizing therapy altered the serum-cytokine profile, but the correlations between HSP70/HSP90/IL-1ra/HGF were maintained only when ATRA + valproic acid were combined with theophyllin but not when combined with cytarabine. We conclude that both HSP levels and serum cytokine profiles are altered and may represent possible therapeutic targets or prognostic markers in human AML.  相似文献   
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