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991.
PH Wiernik DF Moore JM Bennett SE Vogl JE Harris S Luger MM Oken JH Glick 《Canadian Metallurgical Quarterly》1998,30(5-6):601-607
Mitoguazone, an investigational agent with significant activity in advanced lymphoma, was added to a modified CHOP regimen (COPA) in an effort to improve the activity of standard therapy in 66 previously untreated patients with stages II-IV lymphoma and diffuse histology of intermediate or high grade other than lymphoblastic in this phase II pilot study. The regimen was well tolerated and the complete response rate in diffuse large cell lymphoma was 55%. Sixty-five percent of all complete responders were in complete response for at least one year. Despite these excellent results. it is unlikely that the addition of mitoguazone improved results compared with those obtained with standard therapy alone, since similar results have been frequently reported with the latter. 相似文献
992.
Novel thyrotropin-releasing hormone (TRH, pGlu-His-Pro-NH2) analogs, made by solid phase, were derived from the general scaffold pGlu-(D/L)Agl(X)-Pro-NH2 where Agl = aminoglycine. Analogs ranged from X being a proton to an acylating agent derived from substituted (aromatic heterocyclic rings) formic or acetic acids or an aminotriazolyl moiety (3'-amino-1H-1',2',4'-triazolyl) built on N(alpha) of aminoglycine or Nbeta of alpha,beta-diaminoproprionic acid (Dpr). X was expected to mimic the electronic and structural characteristics of the imidazole ring of histidine. Analogs were purified by HPLC, characterized by mass spectrometry and isolated as either diastereoisomeric mixtures or pure isomers. Analogs, tested for their binding affinity to mouse pituitary TRH receptors, have apparent equilibrium inhibitory constants > 1 microM. 相似文献
993.
JE Foley JM Lapointe P Koblik A Poland NC Pedersen 《Canadian Metallurgical Quarterly》1998,12(6):415-423
Feline infectious peritonitis (FIP) is a fatal Arthus-type immune response of cats to infection with FIP virus, a mutant of the ubiquitous feline enteric coronavirus (FECV). The disease may occur systemically or in any single organ system, and primary neurologic disease is a common subset of such manifestations. We examined 16 domestic cats with clinical neurologic FIP and 8 control cats with nonneurologic FIP, with the intention of identifying the ante- and postmortem diagnostic tests that most contribute to accurate diagnosis. Of the 16 cats with neurologic FIP, 15 were less than 2 years of age and all 16 originated from large multiple-cat households. The most useful antemortem indicators of disease were positive anti-coronavirus IgG titer in cerebrospinal fluid, high serum total protein concentration, and findings on magnetic resonance imaging suggesting periventricular contrast enhancement, ventricular dilatation, and hydrocephalus. Postmortem diagnosis was facilitated by FIP monoclonal antibody staining of affected tissue and coronavirus-specific polymerase chain reaction. Most cats with neurologic and ocular forms of FIP had patchy, focal lesions, suggesting that recently developed technologies described in this report may be useful for evaluation of cats with suspected FIP. 相似文献
994.
Feeding a high-carbohydrate (CHO) diet and administration of alkalinizing agents have both been shown to improve performance in high-intensity exercise. The effect of these treatments in combination was investigated in the present study. Six healthy male subjects exercised to exhaustion on an electrically braked cycle ergometer at a power output equivalent to 100% of their maximum oxygen uptake (VO2,max) on four separate occasions. Each subject consumed either a diet with the same composition as his normal diet (termed the experimental normal (N) diet; 54 +/- 7% CHO, 13 +/- 2% protein, 33 +/- 7% fat) or a high-CHO diet (81 +/- 2% CHO, 13 +/- 2% protein, 6 +/- 1% fat) that had the same energy and protein content for the 3 days prior to the exercise tests. Subjects then ingested either a placebo (CaCO3) or trisodium citrate (0.3 g (kg body mass)-1) 3 h before exercise. Time to fatigue was not different between experimental conditions. Consumption of the high-CHO diet had no effect on blood acid-base status, but the ingestion of sodium citrate induced a mild metabolic alkalosis after both the N diet and the high-CHO diet. This alkalinizing effect was also evident after exercise, since blood pH, plasma bicarbonate and blood base excess were higher (P < 0.05) after the ingestion of sodium citrate than under the placebo conditions. The changes in blood lactate, pyruvate and glucose and plasma glycerol after exercise were similar for all experimental conditions. Blood lactate, glucose and pyruvate and plasma glycerol concentrations increased from resting values (P < 0.01) following exercise but this increase was similar under all experimental conditions. These data demonstrate that when the energy and protein content of the diets is the same, exercise capacity and the metabolic response to intense exercise are similar following consumption either of a high-CHO diet or a more normal diet. Acute ingestion of sodium citrate prior to exercise resulted in a reduction in post-exercise acidosis despite a blood lactate concentration that was similar to that observed after the ingestion of a placebo, but did not affect exercise performance under the conditions of this study. 相似文献
995.
By using indirect immunofluorescence we demonstrated the localisation of extracellular matrix (ECM) proteins (laminin--LAM, collagen IV--COL IV, fibronectin--FN) and the basic fibroblast growth factor (bFGF) in rabbit and mouse primary embryonic fibroblasts (PEF). Proliferating mitotically arrested PEF (by mitomycin C) were compared in both species. The stability of protein expression was ascertained during the first five successive passages. In addition, STO cells (i.e. permanent line of irradiated mouse fibroblasts) were similarly analysed. Rabbit PEF showed very high extracellular staining for FN and a negligible cytoplasmic positivity for LAM and COL IV. A totally reversed staining pattern for ECM proteins was found in mouse PEF. A dense cytoplasmic granulation (concentrated around the nucleus) was revealed for LAM and COL IV and almost no reaction for FN. The staining patterns were very stable at the culture conditions we applied. They were maintained during the first five successive passages in proliferating as well as non-proliferating mouse and rabbit PEF and were independent of cell concentration (individually dispersed cells versus cells in a confluent layer). STO cells showed the same staining for ECM proteins as the mouse PEF, thus confirming their origin from the same animal species. Light granular staining for bFGF was found in the cytoplasm of proliferating and mitotically arrested rabbit and mouse PEF and STO cells. The differences in expression of ECM proteins between the rabbit and mouse PEF, as well as the synthesis of bFGF, should be taken into consideration when these cells are used in vitro as a feeder layer for various cells (e.g. embryonic stem cells). 相似文献
996.
JE Semple 《Canadian Metallurgical Quarterly》1998,8(18):2501-2506
Potent serine protease inhibitor 1a featuring a hybrid P3-P4 quaternary lactam dipeptide surrogate was prepared based upon SAR and molecular modeling investigations and in order to further probe the S2/S3 thrombin and FXa subsites. An efficient and concise synthetic route to the key aminolactam intermediate 4 was developed. The design, synthesis, and biological activity of this target and its P3-P4 diastereomer 1b is presented. 相似文献
997.
998.
JG Villa G Cuadrado JE Bayón J González-Gallego 《Canadian Metallurgical Quarterly》1998,77(1-2):106-111
The effects of physical conditioning on antipyrine clearance were studied in two groups of subjects. Healthy men not engaged in the systematic practice of any sport were compared with endurance runners (defined as men running > 80 km/week). Studies were carried out at three different periods of the annual plan training at 4-month intervals. Antipyrine was administered orally and pharmacokinetic parameters were obtained from saliva samples by the multiple-sample method. Endurance performance, expressed in terms of the maximal oxygen uptake (VO2max), the ventilatory threshold and the 4-mM x l(-1) lactate threshold (OBLA), was higher in trained than in control subjects at each of the three periods. Antipyrine clearance was also significantly elevated and antipyrine half-life reduced in runners during all periods. No significant difference in VO2max or antipyrine clearance was found between the various periods in either trained or control subjects. Both ventilatory threshold and OBLA increased significantly along the training period in conditioned subjects. Significant correlations were found between antipyrine clearance and VO2max, ventilatory threshold and OBLA. In summary, these results indicate an association between aerobic conditioning and increased hepatic oxidative metabolism of low-clearance drugs. 相似文献
999.
JE Nestler DJ Jakubowicz AF de Vargas C Brik N Quintero F Medina 《Canadian Metallurgical Quarterly》1998,83(6):2001-2005
To determine whether insulin stimulates human ovarian testosterone production in the polycystic ovary syndrome by activating its own receptor and using inositolglycan mediators as the signal transduction system, thecal cells from polycystic ovary syndrome women were isolated and cultured. Insulin and insulin-like growth factor I stimulated thecal testosterone biosynthesis. Antibody blockade of the insulin receptor abolished insulin's stimulatory action, whereas effective antibody blockade of the insulin-like growth factor I receptor did not alter insulin's stimulation of thecal testosterone biosynthesis. A chiro-inositol containing glycan (INS-2) increased thecal testosterone biosynthesis. Preincubation of cells with an antiinositolglycan antibody (A23939 or alpha IGP) abolished insulin's stimulatory effect, but not that of hCG. These findings suggest that inositolglycans serve as the signal transduction system for insulin's stimulation of human thecal testosterone biosynthesis. 相似文献
1000.
MD Klaiman JA Shrader JV Danoff JE Hicks WJ Pesce J Ferland 《Canadian Metallurgical Quarterly》1998,30(9):1349-1355
PURPOSE: The purpose of this study was to determine whether the pain response after phonophoresis (PH) differs from the pain response after ultrasound (US) alone. METHODS: Forty-nine subjects with soft tissue injuries including epicondylitis, tendinitis, and tenosynovitis were randomly assigned (double blinded technique) to PH or US treatment groups. Both groups received 8 min of continuous US at 1.5 w x cm(-2), three times per week for 3 wk. For the PH group a gel containing 0.05% fluocinonide was used as a coupling agent. An identical gel absent the steroid was used for the US group. Subjects indicated their pain level by marking on a visual analog scale (VAS) at the start of treatment and at the end of weeks 1, 2, and 3. Pressure algometry was used to note tolerance to direct pressure over the target tissue. ANOVA for repeated measures was used to analyze data. RESULTS: At the end of 3 wk of treatment, both groups combined showed a significant decrease in pain level and an increase in pressure tolerance (P < 0.05), but there were no differences between groups from the onset of treatment to the end of week 3 (VAS: US 5.5-1.9, PH 5.0-2.0; algometry (involved limb): US 4.7 lb-7.1 lb, PH 5.1 lb-6.6 lb). CONCLUSIONS: We conclude that US results in decreased pain and increased pressure tolerance in these selected soft tissue injuries. The addition of PH with fluocinonide does not augment the benefits of US used alone. 相似文献