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31.
To analyze the relationship among characteristics of buits, degree of underlying stenosis, and neurologic symptom complexes, the authors studied 157 patients with bruits undergoing digital subtraction angiography. Symptom status assignment (definite lateralizing, possible lateralizing, vertebrobasilar, diffuse, and asymptomatic) and cervical auscultation for location, duration, and other bruit characteristics were performed independently. Bruit occurrence was associated with stenosis of greater than or equal to 50% of the underlying vessel with the association being no stronger at higher levels of stenosis (greater than or equal to 80%). No relationship existed between the side of bruit and side of symptoms in those with lateralized symptoms. The authors found more severe degrees of carotid stenosis in two symptomatic groups (vertebrobasilar insufficiency [VBI] and definite lateralized) compared with asymptomatic patients. Those with VBI had more high-grade stenosis, whereas those with lateralized symptoms had more occlusions, which tended to be ipsilateral to the symptoms.  相似文献   
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We present a case of a newborn with congenital rickets and radiographic evidence of secondary hyperparathyroidism in which the infant's mother had severe, longstanding untreated renal insufficiency.  相似文献   
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BACKGROUND: Patients with cystic fibrosis have received more intravenous antibiotic courses as median survival has steadily increased. A number of centres have adopted a policy of regular (three monthly) rather than on demand intravenous antipseudomonal antibiotics. More widespread bacterial antibiotic resistance has resulted from this increased antibiotic use. Most Pseudomonas aeruginosa strains remain fully sensitive to colistin but its use has been resisted owing to concerns about neurotoxicity and nephrotoxicity. A study was carried out to assess the safety and efficacy of intravenous colistin in the treatment of acute respiratory exacerbations in adult patients with cystic fibrosis. METHODS: Patients with chronic Pseudomonas aeruginosa colonisation who presented with protocol defined respiratory tract exacerbations were randomised to receive treatment for 12 days with either colistin (2 MU tds intravenously) alone or with a second anti- pseudomonal antibiotic. Comparisons of the absolute values of respiratory function tests on days 1, 5, and 12 and of overnight oxygen saturation on days 1 and 12 were the primary outcome measures. Patient's weight, clinical and chest radiographic scores, and peripheral blood markers of inflammation were also documented. The effect of each treatment regimen individually was assessed by the change in clinical measurements from baseline values. Adverse renal effects were monitored by measurement of serum levels of urea and electrolytes, creatinine clearance, and ward urine testing. Neurotoxicity was monitored by direct questioning for symptoms. RESULTS: Fifty three patients, 18 of whom entered the study twice, were enrolled. The mean forced expiratory volume in one second (FEV1) increased significantly in both groups, mean forced vital capacity (FVC) only with dual therapy. Both groups showed a non-significant increase in overnight oxygen saturation. All patients showed clinical improvement. Thirty seven adverse neurological events (two severe) were reported in 33 patients in the monotherapy group and 37 (none severe) in 36 patients in the dual therapy group. One patient withdrew because of severe weakness and dizziness. All other adverse neurological events were well tolerated and resolved during or shortly after treatment. Significant changes were seen in mean serum urea levels in both groups, but in only four patients to a level above the normal range, and in creatinine clearance in the dual therapy group. At 24 month follow up no long term adverse consequences from intravenous colistin were found in patients who completed the study. CONCLUSIONS: Intravenous colistin is an effective treatment for Pseudomonas aeruginosa associated pulmonary exacerbations in patients with cystic fibrosis. Assessment of the individual effect of each treatment regimen suggests a greater efficacy when colistin is combined with a second antibiotic to which the pseudomonas shows in vitro sensitivity. Changes in renal function should be monitored.


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Juvenile hormone (JH)-III 10-11-diol is intrinsically synthesized and released from the corpora allata (CA) of adult locust females in vitro, together with JH-III. JH-III synthesis is preferentially stimulated and diol production only slightly enhanced, by cerebral locust allatotropin. The identification of JH-III diol is based on: similar ratio of incorporation of 14C/3H from radiolabelled [2-14C]acetate and [methyl-3H]methionine, to that of JH-III; similar chromatographic properties to those of synthetic diol on an RP-18 column eluted with acetonitrile, and similar chromatographic properties of acetylated derivatives; mass spectrometric analysis of derivatives and fragmentation products. Exogenous radiolabelled JH-III is not degraded during incubation with locust CA in vitro, corroborating the endogenous production of JH-III diol. Allatal diol formation may be an additional mechanism for the control of JH-III levels in locusts, preceding release into the hemolymph.  相似文献   
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