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61.
Multifocal flash electroretinograms (ERG) were recorded binocularly (n= 18). Areas were equal or scaled with excentricity. The latter were expected to increase the total amplitude if ganglion cell subcomponents were involved. Amplitudes were intercorrelated and the factor structure was established. Scaling had no influence on amplitudes or on factors. Reliability and sensitivity were high. The second kernel first slice from the nine hexagons across the midline showed differences near the macula but no component increasing in latency with distance from the disc. Thus, multifocal flash ERG have linear spatial summation and no ganglion cell subcomponents.  相似文献   
62.
The appendix is an under-appreciated source of chronic pelvic pain. Laparoscopic evaluation of the appendix is limited without intra- operative patient feedback on the presence and absence of pain. New techniques using local anaesthesia with conscious sedation have enabled us to perform operative laparoscopic surgery while the patient is awake. We report the first two cases of microlaparoscopic appendectomies performed under local anaesthesia with conscious sedation following diagnosis obtained during conscious pain mapping.   相似文献   
63.
National admission statistics by diagnosis since 1970, were available from seven WHO member countries. All had officially introduced the ICD 8, but only two countries strictly adhered to the ICD categories in practice. The new 3-digit category 298 (Other psychosis) has met with no success, nor did the new subgroups of schizophrenia with a favourable outcome (295.4, 295.5 and 295.7) gain much acceptance. The discrepancy in diagnostic distribution is virtually unchanged from that before 1970 with a persistent wide concept of schizophrenia in U.S.A. and of depressive illness in England. A new feature is the striking increase in non-psychotic admissions at a time when there is a marked decline in the hospital population. This is taken to indicate that the social stigma attached to the term psychosis persists, and is met with evasion. A preference for unspecified terms (fourth digit 9) is evident, as is the use of terms which leave open whether the patient is psychotic or not (311 in ICD 9). Evidently, instruction in the use of the WHO glossary is called for. In the U.S.A. the replacement of the ICD by the local classification DSM-III is likely to accelerate the reluctance to accept international standards. Moreover, the development of local diagnostic systems for research purposes in England and U.S.A. is not without problems, as there is a disturbing lack of consensus in diagnosis between these two national systems. Obviously, we need the ICD with its clear concepts, and above all the ICD is valuable for securing continuity in diagnostic classification.  相似文献   
64.
Plasma prekallikrein levels, kallikrein activity and antikallikrein levels were investigated in nine premature infants with respiratory distress syndrome (RDS) and six premature infants without. Plasma prekallikrein and kallikrein were determined with a chromogenic substrate measuring amidolytic activity. Antikallikrein was measured with a functional assay. In infants with severe RDS, prekallikrein levels were significantly reduced (median 58% of initial values (p less than 0.01) about 48 hours after onset of symptoms. In infants with moderate RDS prekallikrein level was reduced less, while in babies without RDS there were no significant changes in prekallikrein levels the first 5-7 days of life. Antikallikrein levels did not change significantly in any babies. The results suggest that the kallikrein-kinin system might be involved in RDS. This could explain several features of this syndrome such as hypotension and edema. Furthermore the findings show that homeostatic functions are altered in this disease, and they suggest that other cascade systems as the coagulation, fibrinolytic and complement system may be involved as well. The findings emphasize that trauma might be a significant pathogenetical factor for development of this syndrome and indicate that RDS is not simply a biochemical disease with lack of surfactant as the only pathogenetic factor.  相似文献   
65.
We tested the hypothesis that early brain recovery in hypoxic newborn piglets is improved by resuscitating with an O2 supply close to the minimum level required by the newborn piglet brain. Severely hypoxic 2-5-d-old anaesthetized piglets were randomly divided into three resuscitation groups: hypoxaemic (n = 8), 21% O2 (n = 8), and 100% O2 groups (n = 8). The hypoxaemic group was mechanically ventilated with 12-18% O2 adjusted to achieve a cerebral venous O2 saturation of 17-23% (baseline; 45±1%, mean±SEM). During the 2h resuscitation period, extracellular aspartate and glutamate concentrations in the cerebral striatum were higher during hypoxaemic resuscitation (p = 0.044 and p = 0.055, respectively) than during resuscitation with 21% O2 or 100% O2, suggesting an unfavourable accumulation of potent excitotoxins during hypoxaemic resuscitation. The cell membrane Na+,K+-ATPase activity of cerebral cortical tissue after 2 h resuscitation was similar in the three groups (p = 0.30). In conclusion, hypoxaemic resuscitation did not normalize early cerebral metabolic recovery as efficiently as resuscitation with 21% O2 or 100% O2. Resuscitation with 21% O2 was as efficient as resuscitation with 100% O2 in this newborn piglet hypoxia model.  相似文献   
66.
Hypoxanthine levels in vitreous humor from 32 infants who died of sudden infant death syndrome (SIDS) were determined and compared with levels found in eight children who died of trauma, drowning, or hanging and with levels from seven neonates dying suddenly without long-standing antemortem hypoxia. Determination of hypoxanthine level was done with either a PO2 electrode method or high-performance liquid chromatography. The results obtained by both methods were significantly correlated; therefore they were pooled. The median hypoxanthine level in victims of SIDS (380 mumol/L) was significantly higher (P less than .001) than in the children who died violently (118 mumol/L). Moreover, the levels from the SIDS victims were significantly higher (P less than .001) than those from the neonates who died without long-standing hypoxia (53 mumol/L). It is concluded that SIDS is probably not a sudden event but may be preceded by a relatively long period of respiratory failure and hypoxia.  相似文献   
67.
68.
It took more than 30 years from the first observations that oxygen may be toxic during resuscitation till international guidelines changed to recommend that term and near term newborn infants should be resuscitated with air instead of 100% oxygen. There are still a number of unanswered questions related to oxygen therapy of the newborn infant. The newborn brain, lungs and other organs are susceptible to oxygen injury, and newborns still develop injury caused by hyperoxia.  相似文献   
69.
The rise in infantile autism, learning problems, cognitive decline with age, Alzheimer's, Parkinson's diseases and the SIDS epidemic, has a common cause in the rising dietary deficit in Omega-3 brain-food. This paper suggests that aside from the wider concept of autism spectrum disorders (ASD) and pervasive developmental disorders (PDD), the rise in infantile autism (IA) in the last decade is the effect of deficient brain-food (Omega-3). The consequent delay of development, prolongs the 2nd regressive event in infancy to pruning of the centre in the Medial Frontal Lobe System that connects hippocampus and singulum. With a consequently defective supplementary motor area (SMA), the Delayed Response Function is affected leading to persistent psychosis. Post-pubertal episodic psychoses are associated with acute reduction of excitation, a risk of breakdown of circuitry, insufficient fill-in mechanisms, and silent spots. An acute psychosis occurs if the silent spots compromise SMA. Only two brain areas have continuous neurogenesis, indicating their important functions: the Hippocampus and Olfactory Bulb that belongs to the lateral frontal lobe system essential to survival. Concerned with necessity of action in response to the environment, it relies upon short-term memory and acute feedback mechanisms influenced by emotion and motivation from the external world. In contrast, the medial frontal lobe network is controlled by feed-forward predictive mechanisms related to storage of information The Delayed Response Function is mastered at 7 months, when 2nd event occurs with pruning of axons and dendrites. An abolished or defective delayed response function seriously incapacitates an individual: a defective "social brain" with an inability for conscious action and to communicate, predominates in IA. There is a near lack of speech, despite normal vision and hearing in the minority without marked adversity in pregnancy, at delivery or in infancy. The recent rise in IA despite no rise in adversity signifies a rising deficiency in brain-food. This is suggested by a changing clinical picture: no Mental Retardation in an IA majority. Deficit in olfaction is pathognomonic in schizophrenia since 30 yrs and distinguishes the Asperger syndrome. If brain-food deficiency alone sufficiently prolongs pruning to cause absent activity in SMA in infancy, less mentally retarded IA from other causes might be observed. Deficit in brain-food was evident in the Sudden Infant Death Syndrome: birthweight averaged 200-300g lower than sibs, Omega-3 levels in brainstem were lower than controls. Only 20% SIDS died in first hypoxic episode, suggesting such episodes are more frequent than we imagined. Children with learning-behaviour problems have similarly depressed birthweight. A general deficiency in omega-3 contributes to the lacking reduction in Schizophrenia, despite early puberty predominates. Olfactory bulb is first affected in the Alzheimer's and Parkinson's disease. Cognitive decline with age, hippocampal dysfunctions rises markedly irrespective of disease, but the major mental illnesses and Infantile Autism in particular, benefit from "brainfood" that might also prevent a development of these disorders. To secure optimal brain function in the coming generations, there is a need to change the diet now from its emphasis on protein for body growth to food for the brain. This means there is a need to increase fish and sea food consumption.  相似文献   
70.
Purification of Hageman factor (factor XII) on columns of popcorn- agarose   总被引:6,自引:0,他引:6  
Ratnoff  OD; Everson  B; Donaldson  VH; Mitchell  BH 《Blood》1986,67(6):1550-1553
Purification of Hageman factor (HF, factor XII) from human plasma is a tedious procedure and the product is not always in the precursor form. Hojima has described a protein derived from corn kernels that inhibits the enzymatic properties of HF. This inhibitor binds to the precursor form of HF. Rapid purification of HF was achieved by using as the major purification step adsorption of this clotting factor to popcorn inhibitor bound to agarose. The product had a specific activity of 50.0 to 67.1 coagulant units of HF per milligram protein, and the yield was 33% to 40% of the HF content of the starting plasma. The purified protein displayed a single band upon unreduced or reduced sodium dodecyl sulfate polyacrylamide gel electrophoresis and less than 0.1% was in an activated form, as measured in coagulant assays. The technique described is more rapid and reliable than methods described earlier.  相似文献   
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