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991.
Fifty women with pyelonephritic renal scarring were prospectively followed for five years and the changes in renal function were related to blood pressure control, plasma renin activity, urinary albumin excretion and the incidence of urinary tract infections (UTI). Five patients (10%) developed end stage renal disease. All these patients had bilateral disease, proteinuria and anti-hypertensive treatment at presentation. The mean +/- SD glomerular filtration rate (GFR) of all patients with renal scarring was 74 +/- 27 ml/min x 1.73 m2 at presentation which was significantly lower than the GFR in 55 patients with a recent episode of acute pyelonephritis (p less than 0.001) and 10 healthy controls (p less than 0.001). GFR and age corrected GFR decreased significantly during follow-up (p less than 0.001) and p less than 0.02 respectively). The decrease in GFR was significantly higher in patients with bilateral scarring, in patients on blood pressure treatment and in patients with an episode of symptomatic UTI during follow-up. Eight patients (16%) had antihypertensive treatment at presentation and another 11 patients (26%), of whom 10 had bilateral scarring, developed hypertension (greater than 140/90 mmHg) during follow-up. Seventy-five per cent of all patients had symptomatic UTI and 40% had an episode of acute pyelonephritis during follow-up. In conclusion, patients with pyelonephritic scarring have a high incidence of UTI and are at high risk of developing renal failure and hypertension. It is essential that recurrent episodes of symptomatic UTI are treated promptly and that blood pressure is monitored carefully in these patients.  相似文献   
992.
In this paper, we will discuss a phase-contrast imaging method that avoids the complications of interferometry to provide phase contrast in weakly absorbing samples. A transversely coherent neutron beam is used with the traditional radiography scheme. Images taken with this scheme show dramatic intensity variations due to sharp changes in the neutron wave refractive index. With some numerical processing these images may be used to reconstruct a quantitative phase radiograph of specimens imaged with this technique.  相似文献   
993.
994.
Background: Prenatal exposure to methylmercury (MeHg) and polychlorinated biphenyls (PCBs) has been associated with impaired performance on attention tasks in previous studies, but the extent to which these cognitive deficits translate into behavioral problems in the classroom and attention deficit/hyperactivity disorder (ADHD) remains unknown. By contrast, lead (Pb) exposure in childhood has been associated with ADHD and disruptive behaviors in several studies.Objectives: In this study we examined the relation of developmental exposure to MeHg, PCBs, and Pb to behavioral problems at school age in Inuit children exposed through their traditional diet.Methods: In a prospective longitudinal study conducted in the Canadian Arctic, exposure to contaminants was measured at birth and at school age. An assessment of child behavior (n = 279; mean age = 11.3 years) was obtained from the child’s classroom teacher on the Teacher Report Form (TRF) from the Child Behavior Checklist, and the Disruptive Behavior Disorders Rating Scale (DBD).Results: Cord blood mercury concentrations were associated with higher TRF symptom scores for attention problems and DBD scores consistent with ADHD. Current blood Pb concentrations were associated with higher TRF symptom scores for externalizing problems and with symptoms of ADHD (hyperactive-impulsive type) based on the DBD.Conclusions: To our knowledge, this study is the first to identify an association between prenatal MeHg and ADHD symptomatology in childhood and the first to replicate previously reported associations between low-level childhood Pb exposure and ADHD in a population exposed to Pb primarily from dietary sources.  相似文献   
995.
996.
The aim of the study was to evaluate the potential of autologous bone marrow‐derived nucleated cells to enhance the rate of healing of full‐thickness excisional skin wounds in rabbits. The study was conducted on 20 New Zealand white rabbits of either sex. Two, 2 × 2 cm full‐thickness skin (thoracolumabar region) excisional wounds were created; one on each side of the dorsal midline in each animal. The wounds were randomly assigned to either injection of autologous bone marrow‐derived nucleated cells into the wound margins (BI), or topical application of sterile saline solution (normal saline, NS), which served as control. The wound healing was assessed by evaluation of granulation tissue formation, wound contraction, epithelisation and histopathological and histochemical changes up to 28 days after creation of the wound. Granulation tissue appeared significantly faster in BI‐treated wounds (3.22 ± 0.22 days) than in NS‐treated wounds (4.56 ± 0.47 days). Better epithelisation was seen histologically in BI wounds than in NS‐treated wounds. Wound contraction was significantly more in BI wounds when compared with NS wounds on 21 post‐surgery. Histopathological examination of the healing tissue showed early disappearance of inflammatory reaction, significantly more neovascularisation, and more fibroplasias and early lay down and histological maturation of collagen in BI wounds than in control wounds. It was concluded that injection of autologous bone marrow‐derived nucleated cells in the wound margins induced faster and better quality healing of excisional skin wounds in rabbits when compared with normal saline. The injection of autologous bone marrow‐derived nucleated cells can be used to promote healing of large full‐thickness skin wounds in rabbits.  相似文献   
997.
998.
A systematic survey of in-patient accidents and injuries in an inner London hospital over 9 years established that, after incisions and overdoses, self-incineration was one of the commoner methods of violent self-harm. A case-controlled study of in-patient suicide attempts compared a series of 12 self-incinerators with 12 patients using other methods. Irrespective of method, the suicide attempt was predominantly a psychotic act of young single people with chronic, severe disorders and considerable past parasuicide, in a setting of escalating self-harm. Younger age, greater psychiatric morbidity, absence of alcoholism, a history of childhood arson, past and current self-burning were the features specific to self-incineration, which had a 25% mortality rate.  相似文献   
999.
2,5-Dimethyl-2'-hydroxy-9 alpha-(3-methylbutyl)-6,7-benzomorphan, the 9 beta-analogue, and 9 alpha-N-substituted (N-ethyl, propyl, butyl, pentyl, hexyl, phenylethyl, allyl, and cyclopropylmethyl) compounds were synthesized and evaluated biochemically and pharmacologically. The 9 beta N-methyl compound was found to be as potent as morphine in the mouse hot plate assay and had one-seventh the affinity of morphine for the opioid receptor. The N-alkyl and N-phenethyl 9 alpha-substituted compounds were either inactive or relatively ineffective as antinociceptive agents. None of the examined compounds substituted for morphine in single-dose suppression studies in the rhesus monkey. The N-cyclopropylmethyl compound in the 9 alpha series had half the narcotic antagonist potency of nalorphine and one-eighth of its affinity for the opioid receptor. The 9 alpha-(3-methylbutyl) moiety, unlike bulky substituents in the 9 beta position of 6,7-benzomorphans, generally lowers affinity for the mu opioid receptor and diminishes their in vivo activity as agonists or antagonists.  相似文献   
1000.
Metaphit, 1-(1-(3-isothiocyanatophenyl) cyclohexyl) piperidine, an analog of phencyclidine (PCP) has been shown previously to selectively block PCP receptors and to irreversibly antagonize the depressant effect of PCP in cerebellum. In this study, we examined the electrophysiological interactions of metaphit and naloxone with stereoisomers of cyclazocine, an agent known to have analgesic and psychotomimetic activity in behavioral studies, effects that have been ascribed to opiate and PCP receptor activity. A dose-dependent and reversible slowing of Purkinje neuron discharge was seen with local application of (+)- or (-)-cyclazocine. We found that the blockade of (-)-cyclazocine effects required both high doses of naloxone and the presence of metaphit, whereas the responses to (+)-cyclazocine were blocked by metaphit alone on most cerebellar Purkinje neurons. These findings suggest that the depressant reaction of (+)-cyclazocine in cerebellar Purkinje neurons is primarily mediated through PCP receptors. (-)-Cyclazocine responses, on the other hand, appear to be due to activity at both PCP and kappa opioid receptors.  相似文献   
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