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61.
Recent clinical studies have addressed the utility of sensory evoked potentials (auditory, somatosensory, and visual) in head injury. The clinical significance of evoked potentials in head trauma, states of increased intracranial pressure, and post-traumatic syndrome is discussed. Emphasis is placed on up-to-date studies discussing evoked potential correlation with clinical findings, lesion localization, intracranial pressure, brain herniation, and prognosis. 相似文献
62.
A 36-year-old man who sustained an industrial hyperextension injury of the wrist complained of dysesthesia and pain in the ulnar nerve distribution, aggravated for months by wrist movement until exploration. The operation revealed an anomalous insertion of the flexor carpi ulnaris tendon disrupting a major portion of the ulnar nerve proximal to the pisiform. the symptoms were relieved completely after neurolysis and modification of the insertion of the tendon. 相似文献
63.
64.
True fibromas develop as painless slow-growing nodular tumours. They may appear in any portion of the nail apparatus. The clinical features vary according to their anatomical site. In contrast, the histological features, consisting of a dermal hypocellular reticular nodule with ill-defined demarcation, were similar in all our patients, and factor XIIIa was negative. 相似文献
65.
Denise K Chou Yinzhi Zhao Song Gao Iih-Nan Chou Paul Toselli Phillip Stone Wande Li 《Toxicological sciences》2007,99(1):267-276
To probe mechanisms of cadmium (Cd) damage to the lung extracellular matrix (ECM), we developed Cd-resistant (CdR) rat lung fibroblasts (RFL6) by incubation with graded concentrations of Cd. CdR cells downregulated lysyl oxidase (LO), a copper (Cu)-dependent enzyme essential for crosslinking of collagen and elastin in the ECM, in conjunction with upregulation of other Cu-binding proteins including Cu,Zn-superoxide dismutase (SOD1), copper chaperone for SOD1 (CCS1), metallothionein (MT), and Menkes P-type ATPase (ATP7A), a Cu transporter in the membrane of the Golgi apparatus, as well as gamma-glutamylcysteine synthetase (gamma-GCS), an enzyme for glutathione biosynthesis. Reduction and loss of cytoplasmic distribution of LO in CdR cells were accompanied by its dislocation with the Menkes P-type ATPase and the endoplasmic reticulum marker. CdR cells displayed a defect in LO catalytic activity but an enhancement in Cu,Zn-SOD catalytic activity consistent with the protein expression levels of these enzymes. Although long-term Cd exposure of cells enhanced the Menkes P-type ATPase protein expression, actually, it reduced Cu-dependent catalytic activity of this enzyme in parallel with the deficiency of LO. The low level of 64Cu bound to the LO fraction and the high level of 64Cu bound to the MT fraction provide direct evidence for limitation of Cu bioavailability for LO existing in the CdR cells. These results suggest that downregulation of LO is linked with upregulation of other Cu-binding proteins and with alteration in Cu homeostasis in the CdR phenotype. 相似文献
66.
67.
N. Jain N. Kemp O. Adeyemo P. Buchanan T. W. Stone 《British journal of pharmacology》1995,116(3):2127-2133
1. Purine analogues have been examined for anxiolytic- and anxiogenic-like activity in mice, by use of the elevated plus-maze. 2. The selective A1 receptor agonist, N6-cyclopentyladenosine (CPA) had marked anxiolytic-like activity at 10 and 50 microg kg(-1), with no effect on locomotor performance at these doses. 3. The A1 selective adenosine receptor antagonist, 1,3-dipropyl-8-cyclopentylxanthine (CPX) had no significant effect on anxiety-related measures or locomotor behaviour, but blocked the anxiolytic-like activity of CPA. The hydrophilic xanthine, 8-(p-sulphophenyl) theophylline did not prevent anxiolysis by CPA. 4. Caffeine had anxiogenic-like activity at 30 mg kg(-1) which was prevented by CPA at 50 micro kg(-1). 5. The A2 receptor agonist, N6-[2-(3,5-dimethoxyphenyl)-2(2-methylphenyl)-ethyl]adenosine (DPMA) had no effect on anxiety behaviour but depressed locomotor activity at the highest dose tested of 1 mg kg(-1). The A2 receptor antagonist, 1,3-dimethyl-l-propargylxanthine (DMPX) had no effect on anxiety-related measures or locomotion and did not modify the anxiolytic-like activity of CPA. 6. Administration of DPMA in combination with anxiolytic doses of CPA prevented the anxiolytic-like activity of the latter. 7. The results suggest that the selective activation of central A1 adenosine receptors induces anxiolytic-like behaviour, while the activation of A2 sites causes locomotor depression and reduces the effects of A1 receptor activation. The absence of any effect of CPX alone suggests that the receptors involved in modulating behaviour in the elevated plus-maze in mice are not activated tonically by endogenous adenosine. 相似文献
68.
Induction of a novel form of hippocampal long-term depression by muscimol: involvement of GABAA but not glutamate receptors. 总被引:1,自引:0,他引:1 下载免费PDF全文
1. Unlike long-term potentiation, long-term depression (LTD) in the central nervous system remains poorly understood. The present study was undertaken to investigate the role of GABAA receptors in LTD and synaptic plasticity. 2. Extracellular recordings were made in the CA1 pyramidal cell layer of rat hippocampal slices following orthodromic stimulation of Schaffer collateral fibres in stratum radiatum (0.01 Hz). 3. Muscimol induced a time- and concentration-dependent LTD of the amplitude of orthodromic potentials. Increasing the stimulation frequency from 0.01 Hz to 1 Hz for 10 s reversed the LTD induced by muscimol. Muscimol also induced LTD in the absence of electrical stimulation. 4. Adenosine decreased the spike size in a concentration-dependent manner, but failed to induce LTD. 5. Alphaxalone and 5 alpha-pregnan-3 alpha-ol-20-one at concentrations that did not have any effect themselves on the population spike (0.5 and 1 microM), potentiated the inhibitory effect of muscimol on the population spike size, including concentrations which were not effective by themselves. Both steroids were able to potentiate the ability of muscimol to induce LTD. 6. Bicuculline, 5 microM, reversed the LTD induced by muscimol, 10 microM. 7. The NMDA receptor antagonist (+/-)-2-amino-5-phosphonopentanoic acid (2-AP5), the NMDA/metabotropic antagonist 2-AP3 and selective metabotropic antagonist L-(+)-2-amino-3-phosphonopropionic acid (L(+)-AP3) failed to modify the LTD. Similarly, quisqualic acid and (1S, 3R)-aminocyclopentane dicarboxylic acid (ACPD) a selective agonist at metabotropic receptors did not induce LTD or short-term depression, whereas kynurenic acid prevented the reversal of the LTD obtained at 1 Hz.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
69.
Dr. Steven A. Curley MD Robert A. Newman PhD Thomas B. Dougherty MD PhD George M. Fuhrman MD Diana L. Stone BS Jeffrey A. Mikolajek CRNA Sal Guercio CCP Ann Guercio CCP C. Humberto Carrasco MD M. Tien Kuo PhD David C. Hohn MD 《Annals of surgical oncology》1994,1(5):389-399
Background: We performed a phase I study of a novel system of complete hepatic venous isolation and extracorporeal chemofiltration in
patients with unresectable hepatocellular carcinoma (HCC) to determine (a) whether systemic exposure to doxorubicin could
be limited after high-dose hepatic arterial infusion (HAI), and (b) the hepatic maximum tolerated dose (MTD) of doxorubicin.
Methods: Ten patients with biopsy-proven HCC were treated with 20-min HAI of doxorubicin (17 total treatments). Two patients were
treated with doxorubicin 60 mg/m2, three patients were treated at 90 mg/m2, and five patients received 120 mg/m2. A newly developed dual-balloon vena cava catheter was advanced from the femoral vein, and the balloons were inflated to
isolate and capture total hepatic venous outflow. The hepatic venous blood was pumped through extracorporeal carbon chemofilters
before return of the blood to the systemic circulation.
Results: Peak systemic doxorubicin levels were an average 85.6% lower than were peak prefilter levels (p<0.01). Because all catheters
were placed percutaneously and because the chemofiltration markedly limited systemic chemotherapy exposure, patients were
discharged 1 day after 16 of the 17 treatments. The hepatic and systemic MTD of doxorubicin in this treatment protocol was
120 mg/m2.
Conclusions: This novel system of complete hepatic venous isolation and chemofiltration limits systemic chemotherapy toxicity and will
allow use of higher doses of chemotherapeutic agents to treat HCC.
The results of this study were presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles,
California, March 18–21, 1993. 相似文献
70.