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101.
Sixty-three patients with the clinical diagnosis of acute pancreatitis were submitted to contrast enhanced CT examination. As compared to Ranson's objective clinical parameters, CT grading according to Hill et al. as modified by Balthazar et al. was found to reflect accurately the severity of acute pancreatitis. Evaluation of serial CT examination did not reveal any significant progression in classification during the course of acute pancreatitis. The presence of hypodense areas in the pancreas as a single parameter seems to have a distinct prognostic value. In only one out of five pancreatic abscesses was the presence of gas bubbles observed on CT. It is concluded that contrast enhanced CT has a definite place in the management of acute pancreatitis. 相似文献
102.
AbstractMonitoring Motor Evoked Potential (MEP) to Transcranial Stimulation (TMS) monitoring (MEP) is a growing technique to assess motor function under anesthesia. The following primate study was conducted to analyze the non-myogenic spinal motor and sensory volleys and to examine their reproducibility under nitrous oxide-methohexidone anesthesia. The traveling periodic spinal descending MEP to TMS and ascending somatosensory (SEP) to posterior tibial nerve stimulation across the thoracic cord were recorded in 12 cynomolgus monkeys. Through a small Tn~Tu laminotomy, an insulated stainless steel electrode was inserted into the epidural thoracic space. The potentials were analyzed under 50 vol% NO in 02 with methohexital (0.1-0.2 mg kg~1 min~1). A well-defined periodic TMS-MEPs and PTN-SEPs were recorded with high reproducibility and consistency in repeated trials under N20-methohexital anesthesia. MEP tracing consisted of an initial peak (direct (D) wave), occurring at 2.43 (±0.28) msec followed by subsequent five positive (indirect (I) waves). Spinal SEPs-MEPs were clearly defined, morphologically stable, and consistent over time under N20-methohexitone anesthesia. The present primate study may set a model to monitor both modalities in anesthetized neurosurgical patients.[Neurol Res 1999; 21: 359-367] 相似文献
103.
Byron L. Zamboanga Seth J. Schwartz Lindsay S. Ham Brian Borsari Kathryne Van Tyne 《Cognitive therapy and research》2010,34(2):124-133
Pregaming is a risky drinking behavior that occurs when students drink alcohol before a primary social gathering or event.
The paucity of research on pregaming highlights the need for research on the correlates of drinking behaviors, such as alcohol
expectancies, that might increase the likelihood of pregaming. Thus, we sought to examine how alcohol expectancies and the
valuations (i.e., desirability) of these expectancies are associated with frequency of pregaming, drinking game (DG) participation,
and hazardous alcohol use. Students (N = 1327) from nine U.S. colleges and universities completed self-report surveys. Results showed sufficient discriminant validity
among pregaming behaviors, DG participation, and hazardous alcohol use. Findings also revealed that pregaming mediated the
associations between positive alcohol expectancies and hazardous drinking behaviors. Finally, when we tested for invariance
across gender, ethnicity, and legal versus underage alcohol users, we found full invariance across gender and ethnicity, but
not for legal versus underage alcohol users. Future research directions and potential implications for prevention efforts
are discussed. 相似文献
104.
105.
A surgical tissue adhesive can be made from the patient's own blood. We have been refining the procedures for manufacturing autologous fibrin tissue adhesive to facilitate its use in the operating room and to increase its bonding strength. Fibrin tissue adhesive efficacy depends on fibrinogen concentration. We found that fibrinogen precipitation using the ammonium sulfate method produced the highest concentration. Bonding power was compared with that of the commercial glue 10 minutes and 30 minutes after glueing two pieces of 1 X 1 cm2 human dura together. Bonding strength of the autologous product was close to that of the commercial product. Comparisons of fibrinolysis inhibition time of autologous fibrin tissue adhesive and commercial glue in experiments on rats over a period of one hour to six days after subcutaneous injection are described. 相似文献
106.
A series of experiments was conducted to investigate the rate of Autologous Fibrin Tissue Adhesive (AFTA) degradation by the fibrinolysis inhibitor, epsilon amino caproic acid (EACA). The duration of AFTA clots in vitro, subcutaneous, and in the middle ear was prolonged for a time interval that was proportional to the concentration of EACA in Component II of the adhesive. No toxic reactions were observed in the middle or inner ear. Systemic pathology (thrombosis or emboli) could not be related to the presence of EACA applied in the middle ear or directly into the blood stream at concentrations (mg/kg body weight) up to 1,500 times that expected to occur during surgery on humans. 相似文献
107.
c-Jun and the transcriptional control of neuronal apoptosis 总被引:17,自引:0,他引:17
There has been considerable interest in the molecular mechanisms of apoptosis in mammalian neurons because this form of neuronal cell death is important for the normal development of the nervous system and because inappropriate neuronal apoptosis may contribute to the pathology of human neurodegenerative diseases. The aim of recent research has been to identify the key components of the cell death machinery in neurons and understand how the cell death programme is regulated by intracellular signalling pathways activated by the binding of neurotrophins or death factors to specific cell surface receptors. The aim of this commentary was to review research that has investigated the role of the Jun N-terminal kinase (JNK)/c-Jun signalling pathway in neuronal apoptosis, focusing in particular on work carried out with developing sympathetic neurons. Experiments with sympathetic neurons cultured in vitro, as well as with cerebellar granule neurons and differentiated PC12 cells, have demonstrated that JNK/c-Jun signalling can promote apoptosis following survival factor withdrawal. In addition, experiments with Jnk(-/-) knockout mice have provided evidence that Jnk3 may be required for apoptosis in the hippocampus in vivo following injection of kainic acid, an excitotoxin, and that Jnk1 and Jnk2 are required for apoptosis in the developing embryonic neural tube. However, in the embryonic forebrain, Jnk1 and Jnk2 have the opposite function and are necessary for the survival of developing cortical neurons. These results suggest that JNKs and c-Jun are important regulators of the cell death programme in the mammalian nervous system, but that their biological effects depend on the neuronal type and stage of development. 相似文献
108.
Crockett RJ Dennett JA Ham CM Nunez RD Meisch MV 《Journal of the American Mosquito Control Association》2002,18(1):68-69
Aqua Reslin and Biomist 30:30 technical permethrin and piperonyl butoxide were applied via ground ultra-low volume at a rate of 237 ml/min and 0.00196 kg active ingredient/ha against wild-caught adult Anopheles quadrimaculatus. The 2 formulations did not differ significantly at 31 m from the spray path (P < or = 0.05). However, at 61 and 91 m, percent mortality for 30:30 was significantly higher than for Aqua Reslin at each time after treatment (P < or = 0.05). Between 12 and 24 h, about 8% recovery was observed in mosquitoes treated with Aqua Reslin at 31 m. 相似文献
109.
Little is known about the natural history and management of choroidal neovascularization (CNV) which developed as a complication of laser photocoagulation for central serous chorioretinopathy (CSC). We experienced two patients with CNV which developed after laser treatment for CSC. Submacular membranectomy was performed on both cases after the confirmation of subretinal CNV with optical coherence tomography. One patient received photodynamic therapy for recurrent CNV. The vision of both patients has been improved over 6 months of follow up. These cases suggest that active intervention, including submacular surgery, improves the visual prognosis of this condition. 相似文献
110.
Park KH Shin HJ Song YB Hyun HC Cho HJ Ham HS Yoo YB Ko YC Jun WT Park HJ 《Biological & pharmaceutical bulletin》2002,25(4):457-460
We have studied the effects of ginsenoside Rb1 (GRb1) on the change in lipid contents in rat liver. When GRb1 was administered intraperitoneally to rats, liver microsomal cytochrome P-450 content and NADPH-cytochrome P-450 reductase activity were lower than those in control rats. The contents of triglyceride (TG) and cholesterol were decreased, but those of total phospholipid, phosphatidylcholine, and phosphatidylethanolamine were increased in the GRb1-treated group compared with controls. These results indicate that GRb1 might be involved in lipid metabolism by regulating the activity of microsomal cytochrome P-450 monooxygenase. Although liver TG levels were reduced by GRb1, the levels of TG and beta-lipoprotein in serum from the GRb1-treated group did not change as compared with those in controls. Thus we suggest that the decrease in liver TG levels with GRb1-treatment is not associated with the secretion of TG-rich very low-density lipoprotein. Furthermore, the level of cAMP was also significantly increased in the GRb1-treated group as compared with that in controls. Additionally, the cAMP level was more markedly increased as compared with that in the GRb1-treated group or control group when GRb, was exogenously added to the reaction system for measuring cAMP production in homogenates from control group liver. Accordingly, these results demonstrate that GRb1 might lower TG levels via cAMP-production in the liver, and GRb1 might be an interesting candidate to for a modulator of cAMP-mediated effects, especially within the liver steatosis system. 相似文献