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91.
The purpose of this study was to investigate whether anandamide induces cannabimimetic responses, mainly mobilization of arachidonic acid, in primary cultures of rat brain cortical astrocytes. Confluent monolayer cultures of astrocytes, prelabeled with [3H]arachidonic acid, were incubated with anandamide or delta9-tetrahydrocannabinol (delta9-THC) in the presence or absence of thimerosal, a fatty acid acyl CoA transferase inhibitor and phenylmethylsulfonyl fluoride, an amidohydrolase inhibitor. Anandamide and delta9-THC induced a time- and concentration-dependent release of arachidonic acid in the presence, but not in the absence, of thimerosal. Anandamide- and delta9-THC-stimulated arachidonic acid release was pertussis toxin-sensitive, indicating a receptor/G-protein involvement. A novel and selective cannabinoid receptor antagonist, SR141716A [N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4- methyl-1H-pyrazole-3-carboximide hydrochloride], blocked the arachidonic acid release, suggesting a cannabinoid receptor-mediated pathway. In astrocytes, the magnitude of anandamide-induced arachidonic acid release was equal to that released by equimolar concentrations of delta9-THC. Furthermore, direct assay of amidohydrolase activity indicated that degradation of anandamide into arachidonic acid and ethanolamine was negligible in cortical astrocytes. Our results suggest that anandamide stimulates receptor-mediated release of arachidonic acid, and the receptor may be the cannabinoid receptor. Astrocytes, containing a cannabinoid receptor and lower or negligible amidohydrolase activity, may be an important brain cell model in which to study the cannabimimetic effects of anandamide at a cellular and molecular level.  相似文献   
92.
It is the position of the American College of Sports Medicine that adequate fluid replacement helps maintain hydration and, therefore, promotes the health, safety, and optimal physical performance of individuals participating in regular physical activity. This position statement is based on a comprehensive review and interpretation of scientific literature concerning the influence of fluid replacement on exercise performance and the risk of thermal injury associated with dehydration and hyperthermia. Based on available evidence, the American College of Sports Medicine makes the following general recommendations on the amount and composition of fluid that should be ingested in preparation for, during, and after exercise or athletic competition: 1) It is recommended that individuals consume a nutritionally balanced diet and drink adequate fluids during the 24-hr period before an event, especially during the period that includes the meal prior to exercise, to promote proper hydration before exercise or competition. 2) It is recommended that individuals drink about 500 ml (about 17 ounces) of fluid about 2 h before exercise to promote adequate hydration and allow time for excretion of excess ingested water. 3) During exercise, athletes should start drinking early and at regular intervals in an attempt to consume fluids at a rate sufficient to replace all the water lost through sweating (i.e., body weight loss), or consume the maximal amount that can be tolerated. 4) It is recommended that ingested fluids be cooler than ambient temperature [between 15 degrees and 22 degrees C (59 degrees and 72 degrees F])] and flavored to enhance palatability and promote fluid replacement. Fluids should be readily available and served in containers that allow adequate volumes to be ingested with ease and with minimal interruption of exercise. 5) Addition of proper amounts of carbohydrates and/or electrolytes to a fluid replacement solution is recommended for exercise events of duration greater than 1 h since it does not significantly impair water delivery to the body and may enhance performance. During exercise lasting less than 1 h, there is little evidence of physiological or physical performance differences between consuming a carbohydrate-electrolyte drink and plain water. 6) During intense exercise lasting longer than 1 h, it is recommended that carbohydrates be ingested at a rate of 30-60 g.h(-1) to maintain oxidation of carbohydrates and delay fatigue. This rate of carbohydrate intake can be achieved without compromising fluid delivery by drinking 600-1200 ml.h(-1) of solutions containing 4%-8% carbohydrates (g.100 ml(-1)). The carbohydrates can be sugars (glucose or sucrose) or starch (e.g., maltodextrin). 7) Inclusion of sodium (0.5-0.7 g.1(-1) of water) in the rehydration solution ingested during exercise lasting longer than 1 h is recommended since it may be advantageous in enhancing palatability, promoting fluid retention, and possibly preventing hyponatremia in certain individuals who drink excessive quantities of fluid. There is little physiological basis for the presence of sodium in n oral rehydration solution for enhancing intestinal water absorption as long as sodium is sufficiently available from the previous meal.  相似文献   
93.
Unstretched films of natural rubber (NR) from Hevea brasiliensis were exposed to ozone flow of 15 ml min?1 from 4 to 300 min. The efficiency of reaction was determined by ozone consumption of NR films. Plots of reacted ozone mass versus film thickness show that the ozone penetration and the ozone reaction progressed into deeper layers (170 µm) than described in the literature (~0.5 µm). The previous proposed model based on viscometry measurements was corroborated by ozone consumption results. The effect of thickness on the O3/NR stoichiometric ratio indicated that the diffusion process that controls the ozonation in unstretched film does not consist of the boundary progression behind which all reactive sites have been saturated. Ozonation in unstretched rubber film, while being less efficient than ozonolysis in solution, does have a reaction efficiency of the same order of magnitude. NMR spectroscopy was used to characterise the products formed by ozonation. Copyright © 2004 Society of Chemical Industry  相似文献   
94.
This study compared the effects of angiotensin converting enzyme (ACE) inhibitors captopril versus enalapril on left ventricular (LV) muscle mass and LV systolic and diastolic function in 58 patients with primary glomerulonephritis and moderate chronic renal failure. The design was a 6-8 week titration phase and 6-month maintenance phase. Mean myocardial mass calculated by M-mode echocardiography in the captopril group was 153 +/- 26 g/m2 before, and 130 +/- 14 g/m2 after 6 months of treatment, in enalapril group 147 +/- 22 g/m2 before, and 126 +/- 23 g/m2 after 6 months of treatment (p < 0.05). LV ejection fraction, early and late transmitral flow velocities and early to late LV inflow velocities ratio were not significantly affected by both ACE inhibitors.  相似文献   
95.
96.
From January 1981 through October 1995, a total of 28 patients underwent surgery for metastatic lung tumors in our institute. A retrospective review and survival analysis of these patients are reported. There were 12 males and 16 females, with the mean age of 57 years. Of them, 20 patients had solitary lesions. Pulmonary metastasis was from the colon in 8 patients, from the breast in 5, from the stomach and the uterus in each 3, from the bladder, the rectum and the soft tissue in each 2, and from the kidney, the ovarium and the thyroid in each 1. A lobectomy was performed in 22 patients, 17 of whom were accompanied with mediastinal lymph node dissection (R2a). Partial resection without lymph node dissection was performed in 6 patients (R0). Overall 5-year survival was 24.7%. Four-year or over survivor were 4 patients who underwent a lobectomy with R2a. The patients undergoing lobectomy had a significantly better prognosis compared with patients with partial resection (p<0. 05). The patients with R2a had significantly less local recurrence than patients with R1 or R0 (p<0.05). We conclude that lobectomy with R2a is suitable treatment for metastatic lung cancer.  相似文献   
97.
Mutations in the gene encoding the Survival Motor Neuron (SMN) protein are responsible for autosomal recessive proximal spinal muscular atrophy (SMA). SMN orthologues have been identified in the nematode worm Caenorhabditis elegans and the yeast Schizosaccharomyces pombe but, to date, no human paralogues have been described. Here we describe identification and characterization of an SMN-related protein (SMNrp) gene that encodes a novel protein of 239 amino acids, which has recently been identified as a constituent of the spliceosome complex and designated SPF30. Significant similarity to the SMN protein is apparent only within a central region of SMNrp that represents a tudor domain. The SMNrp/SPF30 gene has been mapped to chromosome 10q23. It is differentially expressed, with abundant levels in skeletal muscle. An exclusively nuclear localization for SMNrp in cultured cells and muscle sections was revealed using GFP fusion constructs and thereafter confirmed with a polyclonal antibody raised against SMNrp. Overexpression of SMNrp as a fusion protein in HeLa cells in culture induced dose-dependent apoptosis with positive TUNEL staining. In addition to a possible role for this protein as a pro-apoptotic factor, SMN and its related protein share significant similarities in sequence and cellular function.  相似文献   
98.
BACKGROUND: Heart transplantation (HT) as a therapeutic option for end-stage chronic Chagas' heart disease (CCHD) is controversial. Reactivation of Trypanosoma cruzi infection and recurrence of the disease in the allograft are likely to occur. Furthermore, active myocarditis has been reported to predispose patients to an increased incidence and severity of rejection. METHODS AND RESULTS: We prospectively investigated the long-term follow-up of 10 patients with CCHD who underwent HT. Immunosuppression was based on cyclosporine A and azathioprine. T cruzi reactivation was prevented with benzonidazole. Besides allograft rejection surveillance, T cruzi infection was monitored through blood tests, myocardial biopsies, and serological tests. Over a mean follow-up period of 34 +/- 38 months (range, 73 to 124 months), 7 patients are alive and in NYHA functional class I. Life expectancy was 78% for the second year and 65% for 10 years. Rejection was less frequent in chagasic than in age- and sex-matched control patients (mean +/- SD, 1.60 +/- 1.26 versus 5.70 +/- 1.89 episodes per patient, respectively; P = .0001); decreased severity of rejection was also observed (P = .006). T cruzi parasitemias detected on three occasions were successfully treated with benzonidazole. There were no signs of recurrence of the disease in the allograft. CONCLUSIONS: These results suggest an important role of HT in the treatment of CCHD. There was a low frequency of T cruzi infection reactivation and no signs of recurrence of the disease in the allograft. The surprisingly decreased rejection incidence and severity require further studies for elucidation.  相似文献   
99.
Multiple biologic effects of interferon-alpha (IFN-alpha), including cell growth inhibition and antiviral protection, are initiated by tyrosine phosphorylation of STAT proteins. Although this signal pathway has been intensively investigated, the relevance of STAT signal persistence has received scant attention. Using paired isogenic lymphoma cells (Daudi), which either are sensitive or resistant to growth inhibition by IFN-alpha, we found comparable initial tyrosine phosphorylation of multiple STAT proteins; however, the phosphorylation durations and associated DNA-binding activities diverged. Phosphorylation and DNA-binding capacity of STAT1 decreased after 4 to 8 hours in resistant cells, as compared with 24 to 32 hours in sensitive cells, whereas phosphorylation of STAT3 and STAT5b was briefer in both lines. Functional significance of the prolonged STAT1 signal, therefore, was explored by experimental interruption of tyrosine phosphorylation, either by premature withdrawal of the IFN-alpha or deferred addition of pharmacologically diverse antagonists: staurosporine (protein kinase inhibitor), phorbol 12-myristate 13-acetate (growth promoter), or aurintricarboxylic acid (ligand competitor). Results indicated that an approximately 18-hour period of continued STAT1 phosphorylation was associated with growth arrest, but that antiviral protection developed earlier. These differences provide novel evidence of a temporal dimension to IFN-alpha signal specificity and show that duration of STAT1 activation may be a critical variable in malignant cell responsiveness to antiproliferative therapy.  相似文献   
100.
To clarify the characteristic features of nosocomial pneumonia in a community hospital, we performed a clinical analysis of 147 patients (155 episodes) with nosocomial pneumonia. The following results were obtained. 1, Regarding the risk factors for nosocomial pneumonia, factors such as the patient whose age was over 65 years, a duration of admission of over one month, performance status 4 and underlying respiratory diseases associated with the appearance of nosocomial pneumonia. 2, The causative microorganism isolated from the sputum of the patient with nosocomial pneumonia was frequently a multi-drug resistant microorganism such as Methicillin-resistant Staphylococcus aureus (MRSA). 3, regarding treatment, although several antibiotics were administered for a long time, mechanical ventilation was used on 31% of the patients, and steroid pulse therapy was carried out on 24%. The clinical efficacy was poor with a 50% mortality rate. The reason why treatment of nosocomial pneumonia was difficult is thought to be been related to the general condition of these inpatients and to the appearance of a multi-drug resistant, polymicrobial microorganisms.  相似文献   
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