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61.
Q Chen  P Sun  I Prigione  H Xie  S Ferrini 《Tumori》1992,78(2):79-86
In an attempt to construct bispecific monoclonal antibodies (bimAbs) able to target cytotoxic T lymphocytes against human hepatoma cells, an HGPRT-deficient mutant of the Hepama-6 hybridoma, which produces an antihuman-hepatoma mAb, was directly fused with splenocytes from Balb/C mice immunized by a polyclonal cytotoxic T-cell line. Hybrid hybridomas were selected in HAT medium, and their supernatants were directly screened for the ability to induce IL-2-cultured cytotoxic T lymphocytes to kill hepatoma cells in a 51Cr-release assay. The selected hybrid hybridoma, termed DQ-33, secretes a bimAb, which reacts with a CD3-associated determinant. When resting peripheral-blood lymphocytes were used as effector cells, virtually no cytolytic activity could be induced by DQ-33, whereas phytohemagglutinin-activated lymphocytes that had been expanded in vitro in IL-2-containing medium could be efficiently targeted against hepatoma cells. Targeting by DQ-33 bimAb was analyzed on different subsets of IL-2-cultured lymphocytes. It was evident that CD+4-8+ TCR alpha/beta+ and CD3+4-8-TCR gamma/delta+ lymphocytes were efficiently induced by bimAb to lyse human hepatoma cells, whereas no induction of cytolysis could be observed when CD3 + 4 + 8-TCR alpha/beta+ cells were used as effectors. DQ-33 bimAb was also able to induce lymphokine secretion (IL-2, GM-CSF and TNF-alpha) by all the different subsets of lymphocytes analyzed in the presence of target cells expressing the relevant antigen, independent of the expression of cytolytic activity.  相似文献   
62.
C Q Wang  H Q Xu  Z P Luo 《中华内科杂志》1992,30(10):643-5, 660
61 patients with cerebellar hemorrhage were studied. The age at onset ranged from 15 to 84 years with a mean of 57.4 years. 49 cases were treated conservatively and 12 surgically and the mortality rates of the two groups were 32.5% and 25% respectively. Based on this study, it is suggested that the clinical and CT indications of surgical treatment of hematoma are as follows; Severe disturbance of consciousness; Bilateral eyeball fixation; Volume of hematoma over 10 ml; Size of hematoma over 4 cm in diameter; Marked acute obstructive hydrocephalus; Compression of cisterna ambieus and quadrigeminus.  相似文献   
63.
64.
There is little information concerning the effects of passive exercise training in healthy humans. This prompted an investigation to evaluate muscle activity and the associated changes in strength and lean body mass resulting from a passive exercise program. Twenty-eight healthy volunteers, aged 26 to 44 years, participated in this six-week study. Lean body mass changes were evaluated by tetrapolar bioelectric impedance measurements, strength changes by isokinetic strength evaluation, and muscle activity by surface EMG techniques. Reproducible muscle activity was recorded in all three muscles studied during two of three preselected exercises. This involuntary muscle activity was attributed to fusimotor and postural reflexes. No significant change (p greater than .05), however, occurred in muscle strength or lean body mass at the end of the six weeks. Lack of these physiologic changes in light of the documented muscle activity is attributed to insufficient training effect.  相似文献   
65.
66.
Although glucocorticoids are widely used to stimulate fetal/neonatal lung function, they also interfere with cellular development in the central nervous system. Dexamethasone was administered to pregnant rats in late gestation at a dose (0.8 mg/kg) that lies just above the threshold for stimulation of lung surfactant synthesis, and the impact on ornithine decarboxylase (ODC) was evaluated in three brain regions. Dexamethasone treatment produced an initial inhibition of basal ODC activity followed by postnatal elevations, a pattern known to be associated with delays in cell replication and differentiation. Dexamethasone also interfered with the ability of the 1-day-old neonate to turn off ODC acutely in response to a 2-h period of maternal separation; as this response conserves energy in the absence of the dam, the effect of dexamethasone is maladaptive. Additionally, dexamethasone sensitized the neonatal brain to hypoxia: the acute increase of ODC associated with a 2-h exposure to 7% O2 was exacerbated in 8-day-old rats exposed to dexamethasone prenatally. These results suggest that administration of dexamethasone, in doses that promote respiratory competence, delays cell development in the central nervous system and renders the brain more vulnerable to adverse neonatal conditions, such as maternal separation or hypoxia.  相似文献   
67.
Soda pop vending machine tipping continues to be a dangerous behavior that can result in lethal or crippling injuries. This study analyzes 64 cases of injuries secondary to crushing by a soda machine. All were male victims except one. The average age was 19.8 years with a range of 5-39 years. Thirteen victims sustained multiple trauma. Fifteen victims were killed. Increased public awareness coupled with support by the government and private industry has contributed to a sharp reduction in incidence of accidents and improved public safety.  相似文献   
68.
This review is intended to provide a balanced view of the role of surgical burn wound excision and closure within the larger context of the total care and rehabilitation of patients with burn injury. The historical background leading to present practice is outlined. The salient technical and logistical problems associated with the performance of wound excision are discussed, with emphasis on the necessity for expeditiously completing these procedures which are associated with major blood loss. A realistic analysis of the results of excisional therapy in patients with burns of varying severity is presented. Benefits attributable to the surgical phase of therapy become progressively more difficult to identify as the size of deep burns increases beyond 20% of total body surface area.
Resumen La presente revisión propone proveer una visión equilibrada del papel de la resección tangencial quirúrgica de la quemadura y su cierre en el contexto más amplio del cuidado total y la rehabilitación de pacientes con lesiones térmicas. Se hace un recuento de los antecedentes históricos y se discuten los más prominentes problemas técnicos y logísticos relacionados con la resección tangencial de la quemadura con énfasis en la necesidad de implementar en forma expedita estos procedimientos, los cuales se asocian con pérdidas mayores de sangre. Se presenta el análisis realista de los resultados de la resección tangencial en pacientes con quemaduras de gravedad variable. Los beneficios atribuibles a la fase quirúrgica de la terapia se hacen progresivamente más difíciles de identificar en cuanto la extensión y profundidad sobrepasan el 20% de la superficie corporal.

Résumé Cette article fait le point sur les avantages et inconvénients respectifs de l'excision et la suture dans le cadre du traitement et la rééducation des grands brûlés. L'historique de cette technique est résumée. Les principaux problèmes de technique et de logistique de l'excision des brûlures sont discutés, en soulignant la nécessité d'assurer un geste rapide enfin de réduire les pertes sanguines. Une analyse réaliste des résultats de la technique excisionnelle des brûlures de sévérité variable est présentée. Les bénéfices directement en rapport avec la chirurgie deviennent plus difficiles à apprécier lorsque la surface brûlée dépasse 20 % de la surface corporéelle.
  相似文献   
69.
70.
Open reduction combined with external compressive skeletal fixation was used to treat twenty-seven patients who had a separated fracture of the patella. Fixation was obtained by the use of two compressive clamps applied to stainless-steel pins that were inserted just proximal and distal to the proximal and distal poles of the patella. Range-of-motion exercises for the knee were begun at two weeks and the pins were removed at three to four weeks. All of the fractures healed. Twenty-four patients regained a range of motion that was equal to that of the opposite knee. There was no evidence of chronic osteomyelitis. Osteoarthritis was noted in one patient who refused excision of a portion of the patella.  相似文献   
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