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排序方式: 共有2707条查询结果,搜索用时 15 毫秒
91.
The study of intrarenal and upper urinary tracts urodynamics in the presence of the ureteropelvic obstruction and of the function of the lower urinary tract shows that congenital hydronephrosis was in 42.8% of cases associated with bladder dysfunction presenting with hyperreflex-type dysfunction. Maladapted hyperreflex bladder was diagnosed in 29.4%, adapted--in 13.5% of cases. The hyporeflex dysfunction occurred in 15.9% of cases. The urinary bladder dysfunction in children with congenital hydronephrosis accounts for 58.7%. These aggravate the same defects of the upper urinary tracts and deteriorate the course of chronic obstructive pyelonephritis. 相似文献
92.
NP Pereira TM Monteiro AC Freitas EJ Barreiro AL Miranda 《Canadian Metallurgical Quarterly》1998,137(3):82-86
A new series 5-thio aryl pyrazole derivatives were proposed aiming analgesic activity. In this work, 8 new compounds of this class were synthesized using usual synthetic methodology, having as key intermediate the 3-methyl-4-nitro-5-chloropyrazole-1-phenyl derivative and subsequent reaction with several nucleophiles sulfides. Pharmacological evaluation of this series showed analgesic activity in the some extent in especially for 5-(4-bromophenyl)-thio-3-methyl-4-nitro-1-phenylpyrazole which was the most potent in this series, presenting an analgesic action comparable to that show by dipyrone. 相似文献
93.
Heart rate (HR) and heart rate variability (HRV) are risk markers in cardiac disease. HRV is also an index of the sympathovagal modulation of heart rate. Their relations have been rarely analyzed. We aimed to study such relations in normal adult conscious rats by using a novel bradycardic agent, a sinus node inhibitor, S-16257. Placebo-drug crossover designs were used while monitoring HR with telemetry and analyzing HRV in both time and frequency domains. S-16257 (2 mg/kg; n = 10) decreased HR by 29% and markedly increased HRV in parallel. By using various combinations of S-16257, atropine (2 mg/kg), and propranolol (4 mg/kg), a positive relation was shown between RR interval and various indexes of HRV: the slower the HR, the greater the HRV. Nevertheless, there is one exception to this correlation. When S-16257 was associated with both atropine and propranolol, the deep bradycardia was accompanied by a reduction of HRV, which indicates that the physiologic negative correlation between HR and HRV is not an intrinsic property of the pacemaker but is highly dependent on the two components of the autonomic system. 相似文献
94.
A tetracyclic, conformationally constrained analogue of delta8-THC (2) has been synthesized in which a two carbon bridge exists between C2 and C2'. Two conceptually related syntheses of 2 are described, both of which employ 5,7-dimethoxy-4-oxo-1,2,3,4-tetrahydronaphthoic acid (11) as starting material. This substrate was converted to 5,7dimethoxy-2-propyl-1,2,3,4-tetrahydronaphthalene (7) and its 4-keto derivative (18). Demethylation of 11 and 18 provided the corresponding resorcinols, which were condensed with trans-p-menthadienol to afford cannabinoid 2, and a keto derivative (20). LiA1H4/A1C1(3) reduction of 20 provided 2. Cannabinoid 2 has relatively low affinity for the cannabinoid brain receptor (Ki = 703+/-98 nM). 相似文献
95.
DF O'Shaughnessy C Tovey AL Miller V O'Neill PS Rana S Akbar MH Thomas 《Canadian Metallurgical Quarterly》1998,15(5):292-293
OBJECTIVE: To assess whether patients with deep vein thrombosis (DVT) could be satisfactorily treated on an outpatient basis with low molecular weight (LMW) heparin and warfarin. DESIGN: A 22 month prospective study of adults attending St Peter's Hospital accident and emergency department with DVT. RESULTS: 1093 patients were referred and assessed; 160 were venogram positive, of which 159 patients between the ages of 22 and 89 years of age have now been treated with LMW heparin as outpatients. Direct liaison with community nurses has minimised the impact on general practitioner workload. CONCLUSIONS: 1272 bed days were saved during this period (an estimated 320,000 pounds). The outpatient treatment of thromboembolism has been shown to be effective and safe. 相似文献
96.
JM Imparl-Radosevich P Li L Zhang AL McKean PL Keeling H Guan 《Canadian Metallurgical Quarterly》1998,353(1):64-72
A number of imidazole-based compounds were tested for their utility as (1)H NMR molecular probes of intracellular pH. Imidazole, previously found useful as a probe of erythrocyte pH, reported a pH in perfused canine glioma cells that was more than 1 pH unit lower than that reported by inorganic phosphate, consistent with the known lysosomal compartmentation of the molecule. Imidazole acetate, also proposed as an NMR probe of cellular pH, was found not to enter the cells of this study. Histidine was found to be readily taken up by cells and reported a pH consistent with that reported by inorganic phosphate. Using the chemical shift of the histidine H2 proton in cells incubated with 10 mM histidine, cellular pH measurements could be obtained in less than 1 s. This compares quite favorably with the measurement time, typically several minutes, needed to assess in vivo pH by (31)P NMR. The use of histidine as a probe of pH is demonstrated in perfused canine and rat glioma cells subjected to ischemia or to low extracellular pH. 相似文献
97.
KH Yeh MT Lin DT Lin JL Tang LT Lui JF Lin YS Chang AL Cheng SC Yu KJ Chang YC Chen 《Canadian Metallurgical Quarterly》1998,49(3):237-244
BACKGROUND: Epidemiologic studies are necessary to determine the prevalence of allergic diseases. This varies widely depending on allergen preparations and patients studied. OBJECTIVE: To investigate the prevalence of atopic disease, skin test reactivity, total and specific IgE to common allergens, and other variables in a sample of students from Málaga, southern Spain. METHODS: Three hundred sixty-five students (age 17.9 +/- 1.18) were interviewed by an allergist. Skin prick tests were performed with Dermatophagoides pteronyssinus, Artemisia vulgaris, Plantago lanceolata, Chenopodium album, Olea europaea, Phleum pratense, Parietaria judaica, Cynodon dactylon, Alternaria tenuis, and cat dander. Total and specific IgE to D. pteronyssinus, Olea, and Parietaria were determined. RESULTS: Of all subjects studied, 19.9% suffered from rhinoconjunctivitis, 4.1% rhinoconjunctivitis plus asthma, 3.1% asthma alone, and 0.8% atopic dermatitis; 46.4% had a positive skin test to at least one allergen (28.2% to D. pteronyssinus, 20.4% to Olea, 13.8% to Phleum); and 43% had total IgE > 100 kU/L and 44.7% a family history of atopy. Allergic symptoms were strongly associated with skin test positivities and family allergic history. Patients with asthma or skin prick test positive had higher total IgE values than others (P < .01). There was a significant correlation between specific IgE values and wheal size in skin test. CONCLUSIONS: Our findings confirm the high prevalence of atopic diseases, and the close relationship of skin tests reactivity (or presence of specific IgE) to allergens with symptoms of asthma and rhinitis. The presence of a family history of allergic diseases influences the development of positive skin tests and atopic illness. Dermatophagoides pteronyssinus and pollen of Olea europaea were found to be the most common allergens. 相似文献
98.
S Ziebe B Bech K Petersen AL Mikkelsen A Gabrielsen AN Andersen 《Canadian Metallurgical Quarterly》1998,13(1):178-181
A new oxidative pathway for the degradation of caffeine(1,3,7-Trimethylxanthine, I) by a mixed culture consisting of strains belonging to the genera Klebsiella and Rhodococcus is presented. The mixed culture does not initiate degradation by N-demethylation either complete or partial, but instead carries out oxidation at the C-8 position resulting in the formation of 1,3,7-trimethyluric acid (TMU, II) which further gets degraded to 3,6,8-trimethylallantoin (TMA, III). Both TMU and TMA are hitherto not shown to be formed in the microbial system. Further degradation of TMA (III) by caffeine grown cells yields dimethylurea (VII) as one of the metabolites. Oxygen uptake studies indicated that caffeine(I) grown cells oxidized TMU(II), TMA (III), glyoxalic acid (VI), dimethylurea(VII), and monomethylurea(V), but not monomethyl and dimethyluric acids. The mixed culture does not accept theophylline(1,3-dimethylxanthine), theobromine(3,7-dimethylxanthine), and paraxanthine(1,7-dimethylxanthine) as the carbon source. 相似文献
99.
T Hawk YQ Zhang G Rajakumar AL Day JW Simpkins 《Canadian Metallurgical Quarterly》1998,796(1-2):296-298
This study was undertaken to determine the effects of estrogen and testosterone on cerebral ischemic lesion size induced by middle cerebral artery (MCA) occlusion in male rats. Rats were gonadectomized and treated with testosterone, estrogen, or testosterone plus estrogen filled Silastic pellets. The animals were divided into 6 groups: intact, intact + estrogen (E2), castrate, castrate + testosterone (T), castrate + E2, and castrate + T + E2. One week after treatment, cerebral ischemia was induced by MCA occlusion for 40 min, followed by reperfusion. After 24 h, rats were sacrificed and slices were then stained to assess lesion size. The presence of testosterone increased and the removal of testosterone decreased lesion size. A strong positive correlation (r2 = 0.922) between plasma testosterone concentrations and ischemic lesion size was observed. Estradiol treatment reduced ischemic area. In summary, the present study provides evidence that testosterone exacerbates and estrogens ameliorate ischemic brain damage in an animal model of cerebral ischemia. 相似文献
100.
J Niebauer CD Pflaum AL Clark CJ Strasburger J Hooper PA Poole-Wilson AJ Coats SD Anker 《Canadian Metallurgical Quarterly》1998,32(2):393-397
BACKGROUND: Recent studies of growth hormone supplementation in chronic heart failure have been associated with variable results. Acquired abnormalities of biochemical parameters of the growth hormone insulin-like growth factor I axis have been associated with severe chronic heart failure. There are suggestions of an acquired growth hormone resistance with deficient insulin-like growth factor I in some patients. OBJECTIVES: Therefore, we set out to investigate the clinical and functional status and the degree of cytokine and neurohormonal alteration of chronic heart failure patients with deficient insulin-like growth factor I responses. METHODS: Patients with chronic heart failure were divided into two groups according to their insulin-like growth factor I levels (classified according to the manufacturer's assay range in normal controls): low insulin-like growth factor I <104 (n = 20; 89 +/- 9.6 ng/ml), and normal/high >104 ng/ml (n = 32; 169 +/- 52 ng/ml). Between groups there was no difference in age (low versus high: 65.3 +/- 12.1 versus 61.6 +/- 9.1 years, p = 0.21), body mass index, aerobic capacity (peak oxygen consumption: low versus high: 15.5 +/- 5.2 versus 17.3 +/- 6.3 mL/kg/min, p = 0.23), left ventricular ejection fraction, New York Heart Association classification. RESULTS: During quadriceps strength testing, patients with low insulin-like growth factor I had reduced absolute strength (-24%), and strength per unit area muscle (- 14%) than patients with normal/high insulin-like growth factor I. Leg muscle cross-sectional area was lower in the low insulin-like growth factor I group (-12% and -13% for right and left legs, respectively). These alterations were accompanied by increased levels of growth hormone (+145%), tumor necrosis factor-alpha (+46%), cortisol/ dehydroepiandrosterone ratio (+60%), noradrenaline (+49%) and adrenaline (+136%) (all at least p < 0.05). CONCLUSIONS: Patients with low insulin-like growth factor I levels show signs of altered body composition, cytokine and neuroendocrine activation, to a greater extent than patients with normal/high levels. 相似文献