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91.
Benoit SC Air EL Wilmer K Messerschmidt P Hodge KM Jones MB Eckstein DM McOsker CC Seeley RJ Woods SC Sheldon RJ 《Physiology & behavior》2003,79(4-5):761-766
The conditioned taste aversion (CTA) is routinely used to assess the aversive consequences of anorexic agents, including potential pharmacological therapies for obesity. In a typical CTA paradigm, rats briefly sampling a novel tastant (e.g., saccharin) are acutely administered with toxin (e.g., lithium chloride, LiCl). After as few as one taste-toxin pairing, rats will reliably avoid the novel tastant. This paradigm is frequently used for the assessment of possible aversive consequences of drugs that are candidates for pharmacological therapies. The degree to which the drug supports development of a CTA is interpreted as an index of its aversive properties. Difficulties with previous work include the inability to assess affects on food intake and CTA simultaneously, particularly during chronic drug administration. We report here two novel CTA paradigms for the assessment of appetitive and aversive consequences of anorexic agents, simultaneously. In the first experiment, animals receive an intraoral infusion of a novel and highly palatable tastant immediately prior to administration of increasing doses of LiCl. In the second experiment, rats were implanted intraperitoneally with osmotic minipumps that chronically delivered a low dose of LiCl for 7 days. LiCl did not affect short or long term food intake in either experiment. However, LiCl did support the development of a CTA in both paradigms. These results suggest that both the appetitive and aversive consequences of anorexic agents can be assessed simultaneously during either acute or chronic drug administration. 相似文献
92.
Oxidative capacity interacts with oxygen delivery to determine maximal O2 uptake in rat skeletal muscles in situ 总被引:2,自引:1,他引:2
When intracellular recordings were made from the antral region of murine stomach, cells with three different patterns of electrical activity were detected. One group of cells generated follower potentials, the second group generated pacemaker potentials and the third group generated slow waves that consisted of primary and secondary components. Slow waves recorded in different regions of the gastric antrum had similar amplitudes but different characteristic shapes. At the greater curvature, slow waves had large initial components. Midway between the greater and lesser curvature, the amplitude of the initial component was reduced and at the lesser curvature an initial component was difficult to detect. When the distributions of myenteric (ICC-MY) and intramuscular interstitial cells of Cajal (ICC-IM) were determined, using an antibody to Kit, ICC-MY were found to be present at the greater curvature but were greatly reduced in density at the lesser curvature. In contrast, ICC-IM were found in the circular layer of each region. When recordings were made from the antrum of W/WV mice, which lack ICC-IM, incomplete slow waves were detected and their amplitudes fell from the greater to the lesser curvature. Again, a corresponding fall in the density of ICC-MY was detected. The observations indicate that the contribution of ICC-MY and ICC-IM to the generation of slow waves varies in different regions of the mouse gastric antrum. 相似文献
93.
Gregg D. Phillips Russell A. Whitehead David R. Knighton 《Developmental dynamics》1991,192(3):257-262
The object of this study was to examine the initiation and pattern of capillary growth associated with wound healing. Collagen sponges were implanted subcutaneously in the hind limbs of adult male rats to stimulate the formation of granulation tissue. Blood vessels of the hind limbs of euthanized rats were perfused with Mercox (an acrylic monomer) via the abdominal aorta at selected periods of time following sponge implantation. When the perfusate was completely cured, the sponge and parajacent tissues were excised and subsequently macerated by alternating immersion in 40% KOH and distilled water. Cast replicas of the vascular lumina were coated with gold and imaged by scanning electron microscopy. At 6 hr, punctate depressions at the periphery of the replicas of vein and venule lumina were noted. The depressions represented sites of leukocyte margination. By 24 hr, the depressions increased numerically, indicating a great increase in the sites of leukocyte margination. The number of these depressions decreased by 48 hr. Concomitantly, the depressions representing endothelial cell nuclei became more pronounced, indicating nuclear hypertrophy of these cells. In addition, capillary bud formation was initiated. At 72 hr, capillary buds were quite apparent and arose solely from venules. Between 7 and 14 days, replicas of capillary lumina were longer and formed an elaborate network, presumably by end-to-end, side-to-side, and end-to-side anastomoses. The network was formed circumferential to the sponge and then capillary sprouts entered the sponge's interstitial spaces. 相似文献
94.
Prerequisites for translating intervention research findings into practice are maintenance of results, generalization of effects and consistency of implementation. This report presents 12 months follow-up information on a randomized 2x2 factorial trial evaluating the incremental effects of adding (1) telephone follow-up or (2) a community resources utilization component to a basic touchscreen computer-assisted dietary goal-setting intervention for 320 type 2 diabetes patients. All conditions evidenced significant improvement from baseline to the 12 months follow-up across behavioral, biological and psychosocial measures. There were few consistent differences between conditions, but results were robust across interventionists and clinics. The telephone follow-up component appeared to enhance long-term results on some measures. When considered along with earlier results from a randomized trial that included a control condition without goal setting, it is concluded that this basic goal-setting intervention can be consistently implemented by a variety of interventionists and produce lasting improvements. 相似文献
95.
A 73 year old woman presented with a right sided adnexal cystic mass. At laparotomy, this proved to be a benign serous ovarian cyst and an aggregation of thin walled subserosal and soft tissue cysts and spongy nodules up to 16 mm in diameter involving the side wall of the uterus and adjacent parametrium. These were removed by total abdominal hysterectomy and bilateral salpingo-oophorectomy. Histologically, the cystic spaces and smaller acini were lined by benign tubo-endometrioid epithelium, with smaller areas typical of serous differentiation and rare microfoci of endocervical-type mucinous epithelium. These features indicated multidirectional Mullerian differentiation in a process that, overall, was consistent with so called florid cystic endosalpingiosis. This lesion is to be distinguished from other benign conditions including multicystic mesothelioma, endometriosis, endocervicosis, florid deep glands of the uterine cervix, and deep Nabothian cysts of the uterine cervix. 相似文献
96.
A circadian context has been used to develop information about the proliferative and functional behavior of the cell populations that function to model the long bones of growing rats. We asked: Are the proliferating cells in the growth cartilages and diaphyseal bone of young adult growing rats distributed within single or multiple populations? Can cytomorphometry (TEM-C) be used to determine ultrastructural correlates to the well-defined circadian rhythm of matrix formation displayed by functionally synchronous populations of metaphyseal osteoblasts? Can TEM-C reveal changes in osteoclast ultrastructure that could index a biological rhythm for osteoclastic bone mineralysis/resorption? Kinetic results derived from multiple radiothymidine labeling (DNA synthesis) support the single population model for chondrocytes and diaphyseal osteoprogenitor cells. TEM-C studies at the midpoints of the daily light and dark spans show that osteoblast RER-membrane development and cysternal volumes are maximal at the recorded daytime peak of net collagen synthesis. The extent of metaphyseal osteoclast surface ruffling (mineralysis) is also twofold greater during the day than the night--an observation supporting the concept that bone formation and resorption activities are coupled. 相似文献
97.
Data from a random survey of household residents in the urban area of Buffalo, stratified by race and education, showed relations between anger-coping styles and age-weight adjusted blood pressure (BP) among males (N = 720). Findings show that older black males with a high reflective mode of anger (constrain anger and try to solve the problem) had significantly lower blood pressure than those with low scores on this mode. In contrast, older black males with a high Anger-out mode (impulsive anger strongly expressed) had significantly higher blood pressure than those low on this mode. This Anger-out pattern was also found for older white men; but for younger whites, only higher alcohol and lower education were significantly related to higher BP levels. An Anger-in mode (impulsive anger not expressed) was not significantly related to blood pressure. The limitations of the Anger-in measures are examined. and a concept of a resentful anger style is discussed and presented for further research. 相似文献
98.
Expression of gtfS is essential for normal insoluble glucan synthesis by Streptococcus downei. 总被引:1,自引:0,他引:1 下载免费PDF全文
The gtfI and gtfS genes of Streptococcus downei were investigated to determine the contribution of the respective enzymes to glucan production in the presence and absence of other glucosyltransferases. Extracts of Escherichia coli expressing cloned gtfS produced a short linear dextran from sucrose which could act as a primer for insoluble glucan synthesis when mixed with extracts of a strain expressing recombinant gtfI. To elucidate the contribution of gtfS to glucan production by S. downei, a mutant was constructed by insertionally inactivating gtfS. S. downei (gtfS mutant) colonies exhibited a marked phenotypic change on sucrose-containing media and a decreased ability to adhere to glass and produced no detectable water-insoluble glucan. These experiments confirm that expression of gtfS is essential for normal insoluble glucan synthesis by S. downei. 相似文献
99.
Russell JH 《Immunologic research》2005,32(1-3):225-229
Much of the understanding of tolerance has focused on the requirements for antigen-specific lymphocyte activation and function.
However, there is increasing evidence for anatomic regulation of effector access to self antigens. Recently, a number of studies
have provided evidence for tissue-specific “addressins” in chemokine/chemokine receptor pairs. The central nervous system
(CNS) provides special anatomic barriers to the movement of cells from the vascular compartment to the parenchyma. Herein
I raise the possibility that antigen, perhaps through specialized antigen-presenting cells, may play a role in regulating
access of activated lymphocytes into the CNS parenchyma. The results suggest that a reexamination of the widely held dogma
that all activated lymphocytes have access to the CNS parenchyma is nessary to understand the relationship between the immune
and central nervous systems. 相似文献
100.
The familial prevalence in second-degree relatives of patients with anxiety neurosis (panic disorder) 总被引:1,自引:0,他引:1
A family history study of second-degree relatives of 19 patients with anxiety neurosis (panic disorder) and 19 controls showed a morbidity risk of 9.5% among the former compared with 1.4% among the latter. These risks were approximately half those found among first-degree relatives. Female relatives were at higher risk for anxiety neurosis. The risk for other psychiatric illnesses did not differ between the relatives of anxiety neurosis and controls. 相似文献