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11.
The effect of a new dihydropyridine slow-channel calcium blocking agent, nisoldipine, on hemodynamics and myocardial blood flow in normal and collateral-dependent areas distal to a chronic coronary artery occlusion were studied in chronically instrumented, conscious dogs. Nisoldipine produced significant and dose-related decreases in arterial blood pressure, an elevation of heart rate and large increases in coronary blood flow velocity. In dogs with an Ameroid constrictor previously implanted to enhance coronary collateral development, this agent produced large increases in perfusion distal to a chronic coronary artery occlusion. In addition, despite a reduction in arterial pressure, nisoldipine preserved renal cortical, intestinal and skeletal muscle blood flow while increasing tissue flow within liver and cerebral cortex. Thus, nisoldipine increases oxygen supply to collateral-dependent myocardium in the presence of reduced driving pressure for collateral perfusion. 相似文献
12.
13.
Incidence of cataract operations in Finnish male smokers unaffected by alpha tocopherol or beta carotene supplements 总被引:1,自引:0,他引:1
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J. M. Teikari M. Rautalahti J. Haukka P. Jarvinen A. M. Hartman J. Virtamo D. Albanes O. Heinonen 《Journal of epidemiology and community health》1998,52(7):468-472
OBJECTIVE: To examine the effect of alpha tocopherol and beta carotene supplementation on the incidence of age related cataract extraction. SETTING: The Alpha-tocopherol Beta-carotene (ATBC) Study was a randomised, double blind, placebo controlled, 2 x 2 factorial trial conducted in south western Finland. The cataract surgery study population of 28,934 male smokers 50-69 years of age at the start. INTERVENTION: Random assignment to one of four regimens: alpha tocopherol 50 mg per day, beta carotene 20 mg per day, both alpha tocopherol and beta carotene, or placebo. Follow up continued for five to eight years (median 5.7 years) with a total of 159,199 person years. OUTCOME MEASURE: Cataract extraction, ascertained from the National Hospital Discharge Registry. RESULTS: 425 men had cataract surgery because of senile or presenile cataract during the follow up. Of these, 112 men were in the alpha tocopherol alone group, 112 men in the beta carotene alone group, 96 men in the alpha tocopherol and beta carotene group, and 105 men in the placebo group. When supplementation with alpha tocopherol and with beta carotene were introduced to a Cox proportional hazards model with baseline characteristics (age, education, history of diabetes, body mass index, alcohol consumption, number of cigarettes smoked daily, smoking duration, visual acuity, and total cholesterol), neither alpha tocopherol (relative risk, RR, 0.91, 95% confidence intervals, CI, 0.74, 1.11) nor beta carotene (RR 0.97, 95% CI 0.79, 1.19) supplementation affected the incidence of cataract surgery. CONCLUSION: Supplementation with alpha tocopherol or beta carotene does not affect the incidence of cataract extractions among male smokers.
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14.
Potent inhibition of HIV-1 entry by (s4dU)35 总被引:2,自引:0,他引:2
Horváth A Tokés S Hartman T Watson K Turpin JA Buckheit RW Sebestyén Z Szöllosi J Benko I Bardos TJ Dunn JA Fésüs L Tóth FD Aradi J 《Virology》2005,334(2):214-223
15.
V D Bokkenheuser N J Richardson J H Bryner D J Roux A B Schutte H J Koornhof I Freiman E Hartman 《Journal of clinical microbiology》1979,9(2):227-232
Campylobacter fetus subsp. jejuni was recovered as the sole bacterial pathogen from 31% of 0- to 8-month-old children with acute gastroenteritis and from 5% of asymptomatic children (P less than 0.05). In children 8 to 24 months old, the respective recovery rates were 38 and 40%. With the exception of one case of simultaneous bacteremia, the clinical course of the symptomatic infection was benign and rarely lasted more than a week. The isolates were sensitive to most commonly used antibiotics. Several isolates shared antigenic determinants with C. fetus subsp. intestinalis. A bacteriophage specific for C. fetus subsp. jejuni lysed 73% of the strains. Several phage-resistant isolates carried a phage that lysed the stock strain of C. fetus subsp. jejuni (NADC 917). 相似文献
16.
D. A. Hartman L. A. Tomchek J. R. Lugay A. C. Lewin T. T. Chau R. P. Carlson 《Inflammation research》1991,34(1-2):84-88
Melittin (MLT) (10 g/paw) and D49 (0.4 g/paw) were injected into the hind paw of male CD-1 mice and elicited 70–80% of maximal paw edema responses at 60 and 30 min after injection, respectively. D49 paw edema was significantly inhibited by anti-histamine/serotonin agents, a PAF antagonist, a PLA2 inhibitor, and some but not all 5-LO and CO inhibitors, indicating that this edema is produced by several classes of inflammatory mediators with mast cell degranulation apparently playing a major role. In contrast, MLT paw edema was not inhibited effectively using the same pharmacological agents except theophylline, suggesting it was elicited via a different sequence of inflammatory events. In summary, D49 and MLT paw edema models were found to be ineffective models to identify experimental PLA2 compounds in our laboratory. 相似文献
17.
Shigella flexneri IpaH(7.8) facilitates escape of virulent bacteria from the endocytic vacuoles of mouse and human macrophages
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Fernandez-Prada CM Hoover DL Tall BD Hartman AB Kopelowitz J Venkatesan MM 《Infection and immunity》2000,68(6):3608-3619
The behavior of Shigella flexneri ipaH mutants was studied in human monocyte-derived macrophages (HMDM), in 1-day-old human monocytes, and in J774 mouse macrophage cell line. In HMDM, strain pWR700, an ipaH(7.8) deletion mutant of S. flexneri 2a strain 2457T, behaved like the wild-type strain 2457T. This strain caused rapid host cell death by oncosis, and few bacterial CFU were recovered after incubation in the presence of gentamicin as previously described for 2457T-infected HMDM. However, analysis of bacterial compartmentalization within endocytic vacuoles with gentamicin and chloroquine indicated that more pWR700 than 2457T was present within the endocytic vacuoles of HMDM, suggesting that ipaH(7.8) deletion mutant transited more slowly from the vacuoles to the cytoplasm. In contrast to findings with HMDM, CFU recovered from pWR700-infected mouse J774 cells were 2 to 3 logs higher than CFU from 2457T-infected J774 cells. These values exceeded CFU recovered after infection of J774 cells with plasmid-cured avirulent strain M4243A1. Incubation with gentamicin and chloroquine clearly showed that pWR700 within J774 cells was mostly present within the endocytic vacuoles. This distribution pattern was similar to that seen with M4243A1 and contrasted with the pattern seen with 2457T. Complementation of pWR700 with a recombinant clone expressing ipaH(7. 8) restored the intracellular distribution of bacteria to that seen with the wild-type strain. Strains with deletions in ipaH(4.5) or ipaH(9.8), however, behaved like 2457T in both HMDM and J774 cells. The distribution profile of pWR700 in 1-day-old monocytes was similar to that seen in J774 cells. Like infected J774 cells, 1-day-old human monocytes demonstrated apoptosis upon infection with virulent Shigella. These results suggest that a role of the ipaH(7. 8) gene product is to facilitate the escape of the virulent bacteria from the phagocytic vacuole of monocytes and macrophages. 相似文献
18.
We identified functional anatomical subdivisions of human lateral and basal temporal cortex related to recent verbal memory for object names, text and auditory words. Extracellular neuronal activity was recorded during memory encoding compared to identification, during encoding, storage or recall retrieval stages of the memory task, during recognition memory, and during implicit memory as measured by repetition priming. Changes in frequency of activity during encoding were recorded from most neurons. In lateral temporal cortex, these encoding changes in the dominant hemisphere were more likely to be polymodal, whereas those in nondominant hemisphere were unimodal. There was substantial separation of neurons with changes in other aspects of memory, defining additional subdivisions. Inferior lateral and basal cortex were related to memory stages, and superior-posterior lateral cortex was related to implicit and recognition memory. 相似文献
19.
Lorne M. Hartman Dr. 《Clinical psychology review》1983,3(4):435-456
This article represents an attempt to clarify questions posed by evidence of varying pathways to change in social anxiety. A new perspective is developed which addresses these questions and, importantly, lays the foundation for an innovative treatment approach. Essentially, social anxiety is construed here as the product of a disorganization in which feelings and cognitions (both conscious and preconscious) about the self, about other people, and about the relations between self and others are organized. Specifically, the socially anxious client experiences others autocentrically: that is, in terms of how the other person perceives, evaluates and affects one's own self. The result is a narrowed capacity for experiencing others. The goal of treatment in the new approach advocated here is to allow the individual to understand, appreciate and share the feelings, thoughts and experience of other people. Therapy is directed toward getting clients out of themselves and into other people. 相似文献
20.
Byron H Hartman Toshinori Hayashi Branden R Nelson Olivia Bermingham-McDonogh Thomas A Reh 《Developmental dynamics》2007,236(10):2875-2883
Notch mediates the process of lateral inhibition that controls the production of hair cells in the inner ear. Hair cells are known to express Notch ligands Dll1 and Jag2, which signal through Notch1 in adjacent supporting cells. However, recent genetic and pharmacological studies indicate that the level of Notch-mediated lateral inhibition is greater than can be accounted for by Dll1 and Jag2. Here, we report that another Notch ligand, Dll3, is expressed in developing hair cells, in a pattern that overlaps that of Dll1 and Jag2. We analyzed the cochleae of Dll3(pu) mutant mice, but did not detect any abnormalities. However, earlier studies have demonstrated that there is functional redundancy among Notch ligands in cochlear development and loss of one ligand can be at least partially compensated for by another. Thus Dll3 may play a role in lateral inhibition similar to that of Dll1 and Jag2. 相似文献