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151.
This study examined the distribution of muscarinic acetylcholine receptor-immunoreactive neurons in the amygdaloid complex of the rat, with emphasis on the central nucleus. The monoclonal antibody M35 raised against purified muscarinic acetylcholine receptor protein was used to visualize muscarinic acetylcholine receptor-immunoreactive cells. Muscarinic acetylcholine receptor immuno-reactivity was high in the central nucleus and low to moderate in all other regions of the amygdaloid complex. Within the central nucleus, the muscarinic acetylcholine receptor-immunoreactive neurons were found predominantly in the lateral subdivision. This region contained medium-sized neurons (largest diameter ranging from 10 to 15 microns), with a round or slightly ovoid cell shape. At the subcellular level, however, the labeled neurons revealed relatively few muscarinic acetylcholine receptor-immunoreactive postsynaptic densities. Immunofluorescent double-labeling demonstrated that nearly all of the muscarinic acetylcholine receptor-immunoreactive neurons (98.6%) in the central nucleus expressed abundant amounts of nicotinic acetylcholine receptors, further substantiating the cholinoceptive character of these cells. In addition, the vast majority of these muscarinic acetylcholine receptor-immunoreactive neurons (94.3%) were GABAergic neurons. The muscarinic acetylcholine receptor-immunoreactive neurons expressed moderate levels of protein kinase gamma, one of the likely intracellular mediators between muscarinic acetylcholine receptors and their elicited physiological response. The number and staining intensity of muscarinic acetylcholine receptor-immunoreactive neurons in the central nucleus varied dramatically among rats. This individual variation correlated positively with the rat's expression of conditioned immobility and correlated negatively with active shock avoidance performance. These results suggest that the GABAergic/cholinoceptive neuronal elements in the central nucleus are involved in the expression of fear-induced behaviors. This interpretation is further elaborated in a forthcoming paper. 相似文献
152.
The 18S rRNA gene (Rns) phylogeny of Acanthamoeba is being investigated as a basis for improvements in the nomenclature and taxonomy of the genus. We previously analyzed Rns sequences from 18 isolates from morphological groups 2 and 3 and found that they fell into four distinct evolutionary lineages we called sequence types T1-T4. Here, we analyzed sequences from 53 isolates representing 16 species and including 35 new strains. Eight additional lineages (sequence types T5-T12) were identified. Four of the 12 sequence types included strains from more than one nominal species. Thus, sequence types could be equated with species in some cases or with complexes of closely related species in others. The largest complex, sequence type T4, which contained six closely related nominal species, included 24 of 25 keratitis isolates. Rns sequence variation was insufficient for full phylogenetic resolution of branching orders within this complex, but the mixing of species observed at terminal nodes confirmed that traditional classification of isolates has been inconsistent. One solution to this problem would be to equate sequence types and single species. Alternatively, additional molecular information will be required to reliably differentiate species within the complexes. Three sequence types of morphological group 1 species represented the earliest divergence in the history of the genus and, based on their genetic distinctiveness, are candidates for reclassification as one or more novel genera. 相似文献
153.
O Olivieri D Girelli M Azzini AM Stanzial C Russo M Ferroni R Corrocher 《Canadian Metallurgical Quarterly》1995,89(6):637-642
The synthetic retinoid, N-(4-hydroxyphenyl)retinamide (4-HPR; Fenretinide), is a cancer chemopreventive and antiproliferative agent whose mechanism of action is unknown. 4-HPR alone is a poor inducer of differentiation of HL-60 cells compared to all-trans-retinoic acid (RA). Here, we found that combinations of 4-HPR and RA synergistically induced differentiation of HL-60 cells. In addition, 4-HPR increased the level of retinoylation, the covalent binding of RA to proteins. Retinoylation occurs in many eukaryotic cell lines and may be involved in RA-induced differentiation. These results suggest that 4-HPR may be a member of a class of retinoids that are active because they displace RA from extracellular and intracellular sites or because they inhibit RA catabolism. On the basis of these proposed mechanisms, retinoids that do not cause differentiation as sole agents may have utility in the clinic in combination with RA. 相似文献
154.
BACKGROUND: BB injuries continue to be one of the most common causes of severe ocular injury among adolescent males. Extraocular and nonperforating anterior globe injuries most commonly result in favorable visual outcomes. The appropriate medical management of both perforating and nonperforating anterior globe injuries resulting from BB trauma and their potential ocular sequelae are reviewed. CASE REPORTS: Three cases illustrating typical as well as atypical anterior globe injuries caused by BBs are presented. Two cases involve nonperforating anterior globe injuries--one with intracranial and one with intraorbital involvement. The third involves a retained intraocular foreign body. The biomicroscopic and ophthalmoscopic features of these injuries are discussed, as are potential complications and management strategies associated with these types of trauma. CONCLUSIONS: Injuries associated with intraocular BBs often result in enucleation if functional vision is not salvageable. Sequelae to such injuries include endophthalmitis, traumatic hyphema, ocular siderosis, and sympathetic ophthalmia. Plain-film radiography and axial computed tomography are critical first steps in determination of the position of any intracranial or intraorbital metallic foreign body. Routine observation for the development of ocular sequelae resulting from retained intraocular, intracranial, and intraorbital BB injuries is recommended. 相似文献
155.
A case of a mandibular cyst, missing of wall lining and containing some solid material is described. The histologic examination showed that this material consisted of osteofibrous tissue with regressive phenomena, inflammatory cells and hyperplastic nervous tissue. On the basis of clinical and histologic findings it is suggested to be a solitary cyst and the solid material due to a local response to an injury suffered by the patient who is a sport practitioner. 相似文献
156.
S Kreindel R Rosetti R Goldberg J Savageau J Yarzebski J Gore A Russo C Bigelow 《Canadian Metallurgical Quarterly》1997,157(7):758-762
The potential of scintigraphy with technetium 99m-labelled J001 (99mTc-J001) to detect synovitis was studied in 15 rabbits with osteoarthritis (OA) of the right knee (section of cruciate ligaments), in five sham-operated rabbits and in four non-operated rabbits. J001 is a non-pyrogenic, acylated poly (1,3) galactoside isolated from the membrane of a non-pathogenic strain of Klebsiella pneumoniae which is able to bind selectively to macrophages via the binding to CD11b and CD14 molecules. The results of 99mTc-J001 scintigraphy were compared with those of scintigraphy with 99mTc-labelled methylene diphosphonate (99mTc-MDP) and GC-APG (a derivative of J001 unable to bind macrophages in vitro). The mean scintigraphic ratios (diseased healthy knee) of 99mTc-J001 were significantly higher in OA rabbits than in sham- and non-operated rabbits, from as early as day 18 until day 90. 99mTc-J001 scintigraphy demonstrated earlier increased uptake than 99mTc-MDP scintigraphy. The mean scintigraphic ratios of 99mTc-J001 were significantly higher than those of 99mTc-GC-APG (which remained normal) in OA rabbits. The normal scintigraphic ratios of 99mTc-J001 in sham-operated and non-operated rabbits, as well as of 99mTc-GC-APG in OA rabbits, suggested that the increased uptake demonstrated with 99mTc-J001 in OA rabbits, as early as day 18 corresponded to imaging of synovitis via elective macrophage targeting. These results showed that 99mTc-J001 scintigraphy should be a specific method of detecting synovitis in OA. 相似文献
157.
In a recent book called Becoming, Gordon Allport points out that there are two approaches to psychology which historically have been called empiricism and rationalism and which he prefers to designate as Lockean and Leibnitzian. The former put the emphasis on the external world and described the human mind as essentially passive; the latter stressed the activity of the individual rather than the environment. With considerable philosophical insight, Allport showed that American psychology followed the leadership of British empiricism-behaviorism and operationalism are good examples of it. The rational position has been more current in Europe. In the psychology of personality, the Leibnitzian position has slowly gained some prominence. But despite the emphasis we are putting on the self and its creative nature, the terminology we use unfortunately is the old language of empiricism. When the word data is used, whether the writer is trying to emphasize what is empirically given or what is phenomenally taken is uncertain. This article recommends a different terminology for the phenomenologist. One might use the word capta for that which is taken from experience or sumpta for that which one takes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
158.
Vitaliano Peter P.; Russo Joan; Scanlan James M.; Greeno Catherine G. 《Canadian Metallurgical Quarterly》1996,11(1):155
Relationships of changes in body mass index (BMI) were examined with changes in psychobehavioral variables in spouse caregivers of individuals with Alzheimer's disease (n?=?81) and matched spouses of controls (n?=?86). Men caregivers had significantly greater BMI and obesity than men controls at both times. Over 15–18 months, women caregivers gained significantly more weight than did women controls. A trend for greater obesity occurred in women caregivers than in women controls at follow-up. Although weight gain was not related to psychobehavioral variables in controls, in men caregivers decreased perceived control and increased fat intake explained significant variance in weight gain. In women caregivers, increased anger control and increased calories explained weight gain. Such caregivers may be at risk for health problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
159.
Replication-defective retroviruses are frequently used as gene carriers for gene transfer into target cells. Here we show that the short half-lives of retroviruses limit the distance that they can effectively travel in solution by Brownian motion, and thus the possibility of successful gene transfer. This physiochemical limitation can be overcome, and effective contact between the retroviral gene carrier and the target cell can be obtained, by using net convective flow of retrovirus-containing medium through a layer of target cells. Using model cell lines (NIH-3T3 and CV-1), it was shown that gene transfer rates can be increased by more than an order of magnitude using the same concentration infection medium. High transduction rates could be obtained even in the absence of polycations, such as Polybrene, which heretofore have been required to achieve reasonable transduction rates. This development may play an important role in realizing human gene therapy. 相似文献