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31.
The MURCS association is traditionally regarded as a disorder limited to the female sex. It has been hypothesized that men displaying the combination of azoospermia, segmentation abnormalities of the cervicothoracic spine and renal anomalies may have a male analogue of MURCS. Here we describe a patient with non-obstructive azoospermia and Klippel-Feil anomaly type II and suggest that this may represent another case of 'MURCS in the male'. 相似文献
32.
Activity-dependent competition between afferents in the primary visual cortex of many mammals is a quintessential feature of neuronal development. From both experimental and theoretical perspectives, understanding the mechanisms underlying competition is a significant challenge. Recent experimental work suggests that geniculocortical afferents might compete for retrograde neurotrophic factors. We show that a mathematically well-characterized model of retrograde neurotrophic interactions, in which the afferent uptake of neurotrophic factors is activity-dependent and in which the average level of uptake determines the complexity of the axonal arbors of afferents, permits the anatomical segregation of geniculocortical afferents into ocular dominance columns. The model induces segregation provided that the levels of neurotrophic factors available either by activity-independent release from cortical cells or by exogenous cortical infusion are not too high; otherwise segregation breaks down. We show that the model exhibits changes in ocular dominance column periodicity in response to changes in interocular image correlations and that the model predicts that changes in intraocular image correlations should also affect columnar periodicity. 相似文献
33.
NR MacIntyre 《Canadian Metallurgical Quarterly》1998,26(12):1955-1956
34.
We have studied the intubating conditions in 60 ASA I or II patients, after induction of anaesthesia with propofol 2 mg kg-1, allocated to one of the following three groups: group 1, remifentanil 1 microgram kg-1; group 2, remifentanil 1 microgram kg-1 and lignocaine 1 mg kg-1; group 3, remifentanil 2 micrograms kg-1. No neuromuscular blocking agents were administered. Intubating conditions were assessed using a four-point scoring system based on ease of laryngoscopy, jaw relaxation, position of vocal cords, degree of coughing and limb movement. Overall intubating conditions were acceptable in 35% of patients in group 1, 100% of patients in group 2 and 85% of patients in group 3. There was a statistically significant drop in blood pressure after induction in groups 2 and 3, and two patients in each group required ephedrine 6 mg i.v. boluses, as dictated by the intervention criteria (mean arterial pressure fall > 25% from baseline). Similarly, there was a drop in heart rate in groups 2 and 3, but this did not reach statistical or clinical significance, and no patient required atropine. 相似文献
35.
NR Kamani 《Canadian Metallurgical Quarterly》1996,17(3):301-304
36.
The use of capacitors to correct for poor power factor is a well-established and cost-effective means of reducing demand and system losses. Utilities routinely apply capacitors on transmission and distribution systems. Additional gains may be made by installing capacitors in customer facilities and many utilities are encouraging such installations for demand-side management (DSM) purposes. Unfortunately, many industrial customers have serious problems with capacitor installations because of interactions with harmonic distortion from plant loads. Capacitors may cause one or more harmonics to be accentuated through resonance. The capacitors themselves may be damaged or the resulting voltage distortion may make it impossible to operate some process equipment. It is often difficult to predict which capacitor installations will be troublesome, particularly when there are numerous capacitors and harmonic-producing loads scattered over a plant's power system. A simplified approach that depends on less input data is described. The method is based on the voltage distortion at the main bus and the currents in the capacitors. Two test cases are presented 相似文献
37.
38.
D Parry A Hextall VP Robinson NR Banner MH Yacoub 《Canadian Metallurgical Quarterly》1996,51(11):1162-4; discussion 1164-5
Successful pregnancy in a single lung transplant recipient has not been reported previously. The long term effect of pregnancy on graft function and management of deteriorating pulmonary function is not defined. This case describes the management, outcome, and problems encountered when a single lung transplant recipient developed a progressive deterioration in pulmonary function during pregnancy, attributed to accelerated obliterative bronchiolitis. 相似文献
39.
Spermine decreased distinctly the activity of Ca2+ -phospholipid-dependent protein kinases, whereas not affected the protein kinase A activity. Content of cytosol estradiol receptors was drastically decreased in rat uterine in presence of the polyamine. The data obtained and literature data suggest that activation of estradiol receptors appears to occur after phosphorylation by means of Ca2+ - dependent protein kinases, which are regulated via phosphoinositide-involving mechanism, i.e. these receptors acquire the ability to bind hormones. 相似文献
40.
During the past 20 years, biologists have become used to finding that proteins first identified in simple, genetically manipulable eukaryotic organisms are conserved in higher eukaryotes. This article draws attention to the similarity between NUDF protein, which is required for nuclear migration in the filamentous fungus Aspergillus nidulans, and a mammalian homologue, LIS1, whose malfunction causes lissencephaly, a neuronal migration disease. The authors suggest that there might be an underlying similarity of mechanism between nuclear migration in the fungus and neuronal migration in the brain. 相似文献