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871.
872.
YL Wang JR Hsieh HS Chung CL Yu AC Ho PP Lu PP Tan 《Canadian Metallurgical Quarterly》1998,89(6):1414-1417
BACKGROUND: Postepidural backache is a common postoperative complaint after lumbar epidural anesthesia. Useful interventions to decrease the incidence of postepidural backache would be helpful. METHODS: We performed a prospective, randomized, double-blind study to compare the effect of local addition of tenoxicam on the incidence of postepidural backache after nonobstetric surgery. One thousand unpremedicated ASA physical status I or II patients scheduled for hemorrhoidectomy were assigned randomly to tenoxicam or control groups. Patients in the control group received 25 ml lidocaine, 2%, with epinephrine 1:200,000 epidurally and 4 ml lidocaine, 1%, for local skin infiltration. Patients in the tenoxicam group received 25 ml lidocaine, 2%, with epinephrine 1:200,000 epidurally and 4 ml lidocaine, 1%, with tenoxicam (2 mg) 1:2,000 for local skin infiltration. Patients were interviewed at 24, 48, and 72 h postoperatively using a standard visual analog scale for evaluation of postepidural backache. A patient was considered to have postepidural backache when the postoperative visual analog scale score was higher than the preoperative score. RESULTS: The incidence of postepidural backache in patients in the control group for the 3 days were 22.8%, 17.4%, and 9.2%, all of which were significantly more frequent than observed in the patients in the tenoxicam group (6.8%, 4.0%, and 1.2%, P < 0.01). There was a significant association between backache and multiple attempts at epidural needle insertion. CONCLUSION: In summary, the local addition of tenoxicam reduced the incidence and severity of postepidural backache. 相似文献
873.
CL Green TP Pretlow KA Tucker EL Bradley WJ Cook AM Pitts TG Pretlow 《Canadian Metallurgical Quarterly》1980,40(6):1791-1796
The Furth murine mastocytoma was adapted to the ascitic form and separated into fractions enriched with respect to lymphocytes and malignant cells by velocity sedimentation in the SZ-14 reorienting zonal rotor or in the isokinetic gradient. Lymphocytes were more highly purified (p less than 0.01) in the isokinetic gradient than in the zonal rotor, i.e., lymphocytes comprised 99.1% of the nucleated cells in the purest fraction from the isokinetic gradient and 80.1% of the nucleated cells in the purest fraction from the zonal rotor. Neoplastic mast cells were similarly purified by the two methods; they comprised 67.7 and 78.5% of the nucleated cells in the purest fractions from the isokinetic gradient and zonal rotor, respectively. Up to 160 million tumor cells can be purified in a single step with the reorienting zonal rotor, whereas 30 to 40 million cells per gradient approach the limit of the isokinetic gradient. After centrifugation in the zonal rotor, recovery was 85.6 +/- 12% (S.D.) of the cells layered over the gradient; and the separated tumor cells retained their ability to form tumors when transplanted into mice. The separation of large numbers of lymphocytes and malignant cells from the same tumor in the SZ-14 rotor should aid in the biochemical and immunological characterization of cancer. 相似文献
874.
The aim of this study was to examine the interaction between N-methyl-D-aspartate (NMDA) receptor activation and the low threshold calcium spike (LTS) of phasically firing neurons in the rostral part of the substantia nigra pars compacta (SNpc) in mid-brain slices. Bath perfusion of 10 microM NMDA gradually increased the LTS area and the effect reached a maximum after 6 min of perfusion. This enhancement of the LTS by NMDA was blocked both by a competitive and non-competitive NMDA receptor antagonist, 50 microM D-AP5 and 10 microM MK801, respectively, demonstrating that this effect of NMDA was mediated through NMDA receptors. Prolonged exposure to increasing concentrations of NMDA (0.1-100 microM) progressively decreased the LTS area. The higher doses led to an irreversible marked depolarization and decrease of the membrane resistance. These results suggest that the LTS of SNpc neurons can trigger a NMDA receptor-dependent response which may have physiological and pathological roles. 相似文献
875.
RD York H Yao T Dillon CL Ellig SP Eckert EW McCleskey PJ Stork 《Canadian Metallurgical Quarterly》1998,392(6676):622-626
Activation of mitogen-activated protein (MAP) kinase (also known as extracellular-signal-regulated kinase, or ERK) by growth factors can trigger either cell growth or differentiation. The intracellular signals that couple growth factors to MAP kinase may determine the different effects of growth factors: for example, transient activation of MAP kinase by epidermal growth factor stimulates proliferation of PC12 cells, whereas they differentiate in response to nerve growth factor, which acts partly by inducing a sustained activation of MAP kinase. Here we show that activation of MAP kinase by nerve growth factor involves two distinct pathways: the initial activation of MAP kinase requires the small G protein Ras, but its activation is sustained by the small G protein Rap1. Rap1 is activated by CRK adaptor proteins and the guanine-nucleotide-exchange factor C3G, and forms a stable complex with B-Raf, an activator of MAP kinase. Rap1 is required for at least two indices of neuronal differentiation by nerve growth factor: electrical excitability and the induction of neuron-specific genes. We propose that the activation of Rap1 by C3G represents a common mechanism to induce sustained activation of the MAP kinase cascade in cells that express B-Raf. 相似文献
876.
OBJECTIVE: Dyspeptic symptoms are common in patients with cervical spinal cord injury (SCI). The supraspinal control of sympathetic innervation to the stomach is interrupted in these patients. Gastric emptying has been reported to be delayed in some patients with cervical SCI. Gastric myoelectrical activity is known to regulate gastric motility and is correlated with gastric emptying. The change in gastric myoelectrical activity after cervical SCI is unknown; our aim was to investigate it. METHODS: The study was performed in 12 cervical SCI patients and 14 healthy controls. Gastric myoelectrical activity was recorded using surface electrogastrography for 30 min in the fasting state and 1 h after a standard test meal. Spectral analysis was performed to compute the following parameters from the electrogastrogram; investigated were the percentage of 2-4 cycles/min (cpm) slow waves, the instability coefficient (IC) of the dominant frequency, the postprandial increment of dominant frequency (deltaF), and its power (deltaP). RESULTS: In both fasting and fed states, regular and stable gastric slow waves were observed in both the control group and patients with cervical SCI. The percentage of normal 2-4 cpm slow waves (preprandial, 80.7+/-3.6% vs 91.5+/-3.7%, p > 0.05; postprandial, 82.0+/-4.4% vs 87.2+/-4.2%, p > 0.05) and IC (preprandial, 0.19+/-0.04% vs 0.28+/-0.05%; postprandial, 0.24+/-0.04% vs 0.27+/-0.02%, p > 0.05) were not significantly different between the two groups. The dominant frequency and its power were also similar between the two groups, no matter whether in the fast (frequency, 2.92+/-0.3 vs 2.93+/-0.06 cpm; power, 30.05+/-1.29 vs 29.08+/-1.23 dB, p > 0.05) or fed (frequency, 3.17+/-0.07 vs 3.02+/-0.06 cpm; power, 32.55+/-0.90 vs 32.07+/-1.18 dB,p > 0.05) state. The postprandial response measured by deltaF (0.25+/-0.09 vs 0.09+/-0.07 cpm, p > 0.05) and deltaP (2.52+/-1.10 vs 2.24+/-1.20 dB, p > 0.05) were also similar between the two groups. CONCLUSION: Gastric myoelectrical activity was not altered after cervical SCI. 相似文献
877.
878.
BM Tyler DJ McCormick CV Hoshall CL Douglas K Jansen BW Lacy B Cusack E Richelson 《Canadian Metallurgical Quarterly》1998,421(3):280-284
Peptide nucleic acids (PNAs) are DNA analogs that can hybridize to complementary sequences with high affinity and stability. Here, we report the first evidence of intracellular delivery of PNAs in vivo. Two CNS receptors, an opioid (mu) and a neurotensin (NTR-1), were targeted independently by repeated microinjection of PNAs into the periaqueductal gray. Behavioral responses to neurotensin (antinociception and hypothermia) and morphine (antinociception) were lost in a specific manner. Binding studies confirmed a large reduction in receptor sites. The loss of behavioral responses was long lasting but did fully recover. The implications of specifically and readily turning off gene expression in vivo are profound. 相似文献
879.
An inbred Arab family with three neonates affected by microlissencephaly syndrome is reported. Brain magnetic resonance imaging in the index case revealed very thin brain mantle with agyria-pachygyria, agenesis of the corpus callosum, and hypoplasia of the brainstem and cerebellum. All three neonates had microcephaly, arthrogryposis multiplex congenita, and micropenis. The presence of three affected newborn infants in a consanguineous family suggests an autosomal-recessive mode of inheritance of this syndrome. The spectrum of microlissencephaly syndrome is reviewed. 相似文献
880.