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31.
Computed tomography (CT) was performed in 189 individuals: in 44 children of schizophrenic parents (high risk group, HRG), in 39 parents with schizophrenia or with schizophrenic disturbance, in 56 children with schizophrenia, in 50 children with consequences of early organic damages of central nervous system (mental retardation syndrome and generalized tic syndrome). The frequency of CT changes was equal in the mentioned groups but their character was quite different. The widening of brain's liquor system (89.7%), the signs of frontal and temporal atrophia (31%), foci of decreased density of cerebral brain's matter, closer in subcortical ganglia and periventricular zone, and different anomalies of brain were observed in HRG children.  相似文献   
32.
90 infants with intrauterine growth retardation (IGR) and 100 normal infants (control group) were followed up from 5 days till 3 years of life. In IGR infants there was a more frequent combination of several neurologic syndromes, an early manifestation of motor disorders (from the very moment of birth), a delay of neuro-psychic development (during the first year of life), a tendency to development of moderate hydrocephalus by the age of 6 months. Autonomic-visceral disorders in them were mostly characterized by the symptoms of abaissement, but not of irritation.  相似文献   
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Two noninvasive tests for assessing pancreatic exocrine function, the cholesteryl-[14C]octanoate breath test and the HPLCN-benzoyl-tyrosyl-p-aminobenzoic acid/p-aminosalicylic acid (NBT-PABA/PAS) test, were simultaneously performed in nine patients with pancreatic exocrine insufficiency due to chronic pancreatitis and in nine healthy volunteers. 14CO2 output in breath and plasma PABA concentration rose slowly in patients but increased rapidly in healthy subjects. The measurement time giving the best discrimination between both groups was 120 min for the cholesteryl-[14C]octanoate breath test and 90 min for the plasma PABA test. At these points, both single-sample tests had essentially identical diagnostic sensitivity. The diagnostic sensitivities of the two single-sample tests were equal to that of the cumulative 6-h urinary PABA recovery and the cumulative 6-h urinary PABA/PAS ratio. We conclude that, for both the cholesteryl-[14C]octanoate breath test and the plasma PABA test, a single test sample is sufficient for rapid detection of impaired exocrine pancreatic function.  相似文献   
35.
Marrow stromal layers were used to investigate the potential role of negative regulators produced by the marrow microenvironment as one potential cause of hematopoietic suppression after chemotherapy and cytokines. Stromal layers were established from marrow of normal or prechemotherapy donors and breast cancer patients after hematological recovery from one cycle of 5-fluorouracil, leucovorin, doxorubicin, and cyclophosphamide and GM-CSF or PIXY321 (GM-CSF/IL-3 fusion protein). Normal donor CD34+ cells were placed in contact with stromal layers, and the number of colony-forming units for granulocytes and macrophages (CFU-GM) was determined. There were 25-79% fewer CFU-GM in post-chemotherapy stromal layer cocultures than in no chemotherapy cocultures. With neutralizing antibody to TNF-alpha the number of CFU-GM in no chemotherapy and post-chemotherapy stromal cocultures was, respectively, 96 +/- 7% (n = 5) and 142 +/- 8% (n = 5) of the number with no antibody treatment. PIXY321 and GM-CSF pretreated stromal layers also suppressed production of CFU-GM. Anti-TNF-alpha promoted an increase in CFU-GM numbers from GM-CSF, but not PIXY321, pretreated stromal cocultures. The results demonstrate that post-chemotherapy marrow stromal layers were deficient in supporting in vitro hematopoiesis and suggest that negative regulators induced by chemotherapy and cytokines may be one cause for this defect.  相似文献   
36.
Escherichia coli primase synthesizes RNA primers on DNA templates for the initiation of DNA replication. The sole known activity of primase is to catalyze synthesis of short RNA chains de novo. We now report a novel activity of primase, namely that it can synthesize RNA from the 3'-hydroxyl terminus of a pre-existing oligodeoxynucleotide. The oligonucleotide-primed synthesis of RNA by primase occurs in both of the G4oric-specific priming system and the dnaB protein associated general priming system. This priming reaction of primase is verified by a number of biochemical methods, including inhibition by modified 3'-phosphate of oligonucleotides and deoxyribonuclease I and ribonuclease H cleavages. We also show that the primed RNA is an effective primer for the synthesis of DNA chain by E. coli DNA polymerase III holoenzyme. The significance of this finding to primases generating multimeric length RNA is discussed.  相似文献   
37.
BACKGROUND: This report describes the complication of pulmonary vein stenosis with resultant severe pulmonary hypertension that developed in 2 patients after successful catheter ablation of chronic atrial fibrillation. METHODS AND RESULTS: Three months after successful catheter ablation of atrial fibrillation, both patients developed progressive dyspnea and pulmonary hypertension. Both were found to have severe stenosis of all 4 pulmonary veins near the junction with the left atrium. Balloon dilation of the stenotic pulmonary veins was performed in these patients, with improvement in dyspnea and pulmonary hypertension. CONCLUSIONS: The complication of pulmonary vein stenosis is potentially life-threatening, and the application of radiofrequency current within the pulmonary veins with standard catheter technology should be avoided. This complication can be treated with balloon dilation, although the long-term course is unknown.  相似文献   
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Experimental determinations were made of the electrical conductivity of ion-exchange membranes as a function of degree of hydration and temperature, as well as determinations of membrane moisture content as a function of the partial water-vapor pressure above the membrane and of temperature.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 21, No. 4, pp. 619–626, October, 1971.  相似文献   
40.
Transections of the chicken spinal cord after the developmental onset of myelination at embryonic day (E) 13 results in little or no functional regeneration. However, intraspinal injection of serum complement proteins with complement-binding GalC or 04 antibodies between E9-E12 results in a delay of the onset of myelination until E17. A subsequent transection of the spinal cord as late as E15 (i.e., during the normal restrictive period for repair) results in neuroanatomical regeneration and functional recovery. Utilizing a similar immunological protocol, we evoked a transient alteration of myelin structure in the posthatching (P) chicken spinal cord, characterized by widespread "unravelling" of myelin sheaths and a loss of MBP immunoreactivity (myelin disruption). Myelin repair began within 7 d of cessation of the myelin disruption protocol. Long term disruption of thoracic spinal cord myelin was initiated after a P2-P10 thoracic transection and maintained for > 14 d by intra-spinal infusion of serum complement proteins plus complement-binding GalC or 04 antibodies. Fourteen to 28 d later, retrograde tract tracing experiments, including double-labeling protocols, indicated that approximately 6-19% of the brainstem-spinal projections had regenerated across the transection site to lumbar levels. Even though voluntary locomotion was not observed after recovery, focal electrical stimulation of identified brainstem locomotor regions evoked peripheral nerve activity in paralyzed preparations, as well as leg muscle activity patterns typical of stepping in unparalyzed animals. This indicated that a transient alteration of myelin structure in the injured adult avian spinal cord facilitated brainstem-spinal axonal regrowth resulting in functional synaptogenesis with target neurons.  相似文献   
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