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91.
92.
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   
93.
To investigate the functional organization of higher brain levels in fish we test the hypothesis that the dorsal gray mantle of the telencephalon of a mormyrid fish has discrete receptive areas for several sensory modalities. Multiunit and compound field potentials evoked by auditory, visual, electrosensory, and water displacement stimuli in this weakly electric fish are recorded with multiple semimicroelectrodes placed in many tracks and depths in or near telencephalic area dorsalis pars medialis (Dm). Most responsive loci are unimodal; some respond to two or more modalities. Each modality dominates a circumscribed area, chiefly separate. Auditory and electrical responses cluster in the dorsal 500 micrometer of rostral and caudolateral Dm, respectively. Two auditory subdivisions underline specialization of this sense. Mechanoreception occupies a caudal area overlapping electroreception but centered 500 micrometer deeper. Visual responses scatter widely through ventral areas. Auditory, electrosensory, and mechanosensory responses are dominated by a negative wave within the first 50 msec, followed by 15-55 Hz oscillations and a slow positive wave with multiunit spikes lasting from 200 to 500 msec. Stimuli can induce shifts in coherence of certain frequency bands between neighboring loci. Every electric organ discharge command is followed within 3 msec by a large, mainly negative but generally biphasic, widespread corollary discharge. At certain loci large, slow ("deltaF") waves usually precede transient shifts in electric organ discharge rate. Sensory-evoked potentials in this fish pallium may be more segregated than in elasmobranchs and anurans and have some surprising similarities to those in mammals.  相似文献   
94.
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   
95.
OBJECTIVE: To provide recommendations for the treatment of acquired immunodeficiency syndrome-related cytomegalovirus (CMV) end-organ diseases, including retinitis, colitis, pneumonitis, and neurologic diseases. PARTICIPANTS: A 17-member panel of physicians with expertise in clinical and virological research and inpatient care in the field of CMV diseases. EVIDENCE: Available clinical and virological study results. Recommendations are rated according to the quality and strength of available evidence. Recommendations were limited to the treatment of CMV diseases; prophylaxis recommendations are not included. PROCESS: The panel was convened in February 1997 and met regularly through November 1997. Subgroups of the panel summarized and presented available information on specific topics to the full panel; recommendations and ratings were determined by group consensus. CONCLUSIONS: Although the epidemiological features of CMV diseases are changing in the setting of potent, combination antiretroviral therapy, continued attention must be paid to CMV diseases in patients infected with the human immunodeficiency virus to prevent irreversible endorgan dysfunction. The initial and maintenance treatment of CMV retinitis must be individualized based on the characteristics of the lesions, including location and extent, specific patient factors, and characteristics of available therapies among others. Management of relapse or refractory retinitis must be likewise individualized. Ophthalmologic screening for patients at high risk for retinitis or who have a prior diagnosis of extraretinal disease is recommended. Recommendations for gastrointestinal, pulmonary, and neurologic manifestations are included.  相似文献   
96.
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   
97.
98.
A review of 35 patients > 60 years of age with odontoid fractures showed that a type II injury (Anderson and D'Alonso) was the most common fracture pattern (82% of cases). On the basis of mechanism of injury and sex incidence, we deduced that osteopenia is a contributory factor in the occurrence of odontoid fractures. A fall in a domestic setting was the cause in 53%. The peg was posteriorly displaced in 88% of type II fractures, and primary union occurred in 23%. The incidence of concomitant spinal cord injury with type II fractures was higher in older patients than it was in those < 60 years of age. The outcome for these patients was largely determined by their neurological status at presentation. Myelopathy as a late complication of nonunion was not observed in nine patients with an average follow-up of 21 months. The data suggest that vigorous attempts to secure both primary union and a sound arthrodesis for non-union are questionable in the elderly except in unusual circumstances.  相似文献   
99.
The pharmacokinetics of vancomycin were evaluated simultaneously using both arterial and venous plasma data in five rabbits after a rapid bolus intravenous (i.v.) dosing. Initial arterial to venous concentration ratios at 5 s after i.v. injection were the highest, with values of 27.1, 36.2, 36.6, 43.7 and 29.7 for rabbits 1-5, respectively. This could be the result of diffusion of vancomycin from the arterial plasma into the extravascular tissues. Both curves decayed in parallel at the terminal phase with the venous levels higher than the arterial levels by 23, 37, 34, 13 and 14% for rabbits 1-5, respectively. This difference could be the result of continuous release of vancomycin from the extravascular tissues to the venous blood. Detailed analysis showed differences in various pharmacokinetic parameters based on arterial and venous data. For example, values for venous Vc were 9.2, 11, 1.9, 7.2 and 8.8 times greater than the arterial values for rabbits 1-5, respectively. The values for both venous Vss and MRT were higher than those of the arterial values in all five rabbits studied. This could be due to more extensive distribution of vancomycin in the extravascular tissues. A plot of 1/Q (urine flow rate) versus 1/ClR of vancomycin yielded a straight line in rabbits 6-10, indicating that the renal clearance of vancomycin in rabbits is dependent upon urine flow.  相似文献   
100.
The purpose of this study was to examine the effects of low density lipoprotein (LDL) on Ca2+ transients of isolated rabbit cardiomyocytes. Incubation of cardiomyocytes with > or = 1 mg of LDL cholesterol/ml of perfusion medium induced a slow (> or = 30 min) but significant increase (2-fold) in the cellular Ca2+ transient. The time course for the effect was similar to that observed for the accumulation of cholesterol in the cells. Using Dil- labeled LDL as a fluorescent marker for LDL interaction with the cardiomyocytes, it was concluded that LDL interacted via a receptor-mediated event, but probably this was not the primary mechanism whereby the lipid entered the cell. LDL-treated cells were resistant to the depressant actions for ryanodine, nicardipine, and dichlorobenzamil on the cellular Ca2+ transient. Lowering the extracellular Ca2+ concentration removed the stimulatory effect of LDL on the Ca2+ transient. It is concluded that LDL can induce an increase in the magnitude of the Ca2+ transient in isolated cardiomyocytes. This is a relatively slow process. The mechanism appears to involve a stimulation of a transsarcolemmal Ca2+ transport pathway. These findings have important implications for cardiac contractile function in hypercholesterolemic and drug-treated hypercholesterolemic subjects.  相似文献   
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