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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   
4.
Healthy aged adul (24–26 months of age) and young adult (2–4 months of age) C57BL/6J male mice were assessed for intermale aggression, pup-killing behavior (infanticide), and circulating levels of testosterone (T). When compared to young adult male mice, aged adult males were highly variable in the exhibition of both androgen-dependent behaviors. Significant numbers of aged males exhibited deficits in aggression and pup-killing while other animals were as behaviorally active as their young male counterparts. Assessment of serum T showed that aging did not produce a reduction in levels of the steroid and individual variability in androgen-dependent behavior of aged males was not related to plasma levels of the hormone. When aged non-aggressive and non-killer males were exposed to supplemental T by way of subcutaneously implanted silastic capsules, circulating levels of the steroid were elevated but T-dependent behavior was not recovered. These findings, in combination with those previously reported for copulatory behavior, indicate that the deficits observed in the androgen-dependent behavior of aged male mice cannot be attributed to a breakdown in the production of testicular androgens. While neural refractoriness to T may account in part for deficits in androgen-dependent behavior of aged males, the variability that is observed in the reproductive behaviors of aged male rodents ultimately may be related to other sources of variation such as perinatal environment.  相似文献   
5.
6.
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   
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.
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   
9.
Central or systemic administration of morphine disrupts maternal behavior in steroid-primed, pup-induced virgin and lactating rats. Morphine, the prototypical mu agonist, also interacts with different opioid receptor subtypes. The present study examined the effectiveness of five receptor-selective agonists, in addition to morphine, to disrupt maternal behavior in primiparous lactating rats following intracerebroventricular (i.c.v.) infusions in order to characterize opioid receptor subtype involvement in maternal behavior in the female rat. Virgin, Sprague-Dawley rats were mated and implanted with lateral ventricle cannulae on days 13-15 of gestation. On postpartum day 5, mothers were tested for maternal behavior 30 min after i.c.v. vehicle infusion (5 microliters). On day 6, rats received one of the following opioid receptor agonists 30 min before testing: beta-endorphin (mu/epsilon receptor subtype; 0.29, 0.72, 1.45, 2.9 nmol), DAGO (mu; 0.29, 0.72, 1.45, 2.9 nmol), morphine (mu; 0.29, 0.72, 1.45, 2.9, 14.5 nmol), DPDPE (delta; 2.9, 29 nmol), U50488H (kappa l; 2.9, 29, 145 nmol) and SKF10047 (sigma; 2.9, 29, 145 nmol). Only activation of mu opioid receptors dose-dependently disrupted maternal behavior in primiparous lactating rats. DPDPE, U50488 and SKF10047 had no discernible effect on maternal behavior. DAGO, a highly selective mu agonist, was even more potent than beta-endorphin and morphine in disrupting maternal behavior suggesting that maternal behavior is regulated by opioids interacting with the mu opioid receptor.  相似文献   
10.
Paraganglioma in pregnancy is an exceedingly rare and potentially life‐threatening diagnosis. It is important that the clinicians consider secondary causes when women present with hypertension in early pregnancy.  相似文献   
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