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21.
  • 1 There is strong evidence for a renal basis to the development of hypertension in the spontaneously hypertensive rat (SHR). Alterations of the SHR renal vasculature, including the glomerulus, may be involved in the initiation and maintenance of hypertension in this animal model.
  • 2 The arterial walls of pre-glomerular vessels of the SHR are hypertrophied compared with WKY vessels. Unlike other vascular beds in the SHR, this hypertrophy is independent of angiotensin II (AngII).
  • 3 Glomerular number and volume are similar between SHR and the normotensive Wistar-Kyoto (WKY) rats. These results provide no support for the theory that a reduced filtration surface area within the kidneys of the SHR contributes to the elevated blood pressure in these animals.
  • 4 Intrarenal hypertrophy may have similar haemodynamic consequences to clipping of the main renal artery, as in Goldblatt hypertension. Further analysis of the role of pre-glomerular arterial hypertrophy is warranted to determine its involvement in the initiation and maintenance of hypertension in the SHR.
  相似文献   
22.
EDITORIAL COMMENT: This case report was accepted for publication because of the clinical lesson it delivers, namely that intracranial tumours, although rare in pregnancy, may as the authors state 'produce a wide variety of symptoms that are difficult to distinguish from the more common symptoms of pregnancy, including nausea, vomiting and headache'. This case suggests that examination of the optic fundi is essential in patients with neurological symptoms even when/especially when there is a history of psychiatric illness.  相似文献   
23.
The literature on subjective memory concerns (SMC) as a predictor for future cognitive decline is varied. Furthermore, recent research has pointed to additional complexity arising from variability in the experience of SMC themselves (i.e. whether they are remitting or sustained over time). We investigated the associations between SMC and objectively measured cognition in an Australian population-based cohort. Four waves (4-year intervals between waves) of data from 1236 participants (aged 62.4 ± 1.5 years, 53% male) were used. We categorized participants as experiencing SMC, when they indicated that their memory problems might interfere with their day-to-day life and/or they had seen a doctor about their memory. SMC was categorized as “no” reported SMC, “remitting”, “new-onset” or “sustained” SMC. Cognitive assessment of immediate and delayed recall, working memory, psychomotor speed, attention and processing speed were assessed using a neuropsychological battery. Eighteen percent of participants were characterised as having SMC: 6% (77) “remitting”, 6% (77) “new-onset” and 6% (69) “sustained” SMC. There was no consistent evidence for an association between SMC and subsequent decline in cognition. However, SMC was associated with poorer performance on contemporaneous tasks of attention and processing speed compared to “no” SMC. Asking about SMC may indicate a current decline in cognitive function but, in this sample at least, did not indicate an increased risk of future decline.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10433-022-00694-2.  相似文献   
24.
二氢青蒿素的变旋作用与差向异构体转化研究   总被引:5,自引:0,他引:5  
王仲山  曹秀玲 《药学学报》1988,23(8):610-615
二氢青蒿素在极性溶媒中,其旋光度随时间而变化,可达一恒定值。高效液相色谱测定表明,在溶液中,该物质有一自β差向异构体向α型转化的动力学过程,此过程与旋光度的变化相对应,其转化速率常数随溶剂、温度而异,酸具催化作用。这一现象的本质是半缩醛的变旋作用。  相似文献   
25.
Diabetes mellitus associated with cystic fibrosis   总被引:4,自引:0,他引:4  
The prevalence of overt diabetes mellitus and carbohydrate intolerance was studied in 448 patients with cystic fibrosis (CF). Insulin-dependent diabetes (IDDM) developed in 7.6% of patients (13 male and 21 female). Survival was significantly lower (P less than 0.01) in the IDDM-CF group, with fewer than 25% surviving to age 30 years, whereas nearly 60% of the nondiabetic CF population reached this age. A significant deterioration in CF clinical status, based on NIH score, became apparent 2 years before onset of overt IDDM (P less than 0.05 at 2 years prior, P less than 0.01 at IDDM diagnosis). Total glycosylated hemoglobin (HbA1) was significantly (P less than 0.001) higher for the total CF population (7.3% +/- 1.2%) than for the general non-CF population (6.5% +/- 0.7%), and in the IDDM-CF group (P less than 0.05) compared with normoglycemic CF control patients. Female patients had a higher mean HbA1 after 12 years of age than their male counterparts did (P less than 0.02). HBA1 did not predict the development of IDDM, but there was a weak inverse relationship between HbA1 and both NIH clinical score (r = -0.41, P less than 0.02) and standard pulmonary function tests (forced vital capacity, r = -0.25, P less than 0.01) in the general CF population. Therefore, impaired carbohydrate tolerance in CF is associated with progressive clinical deterioration.  相似文献   
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