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排序方式: 共有515条查询结果,搜索用时 31 毫秒
1.
Omar P. Sangüeza Julie K. Salmon Clifton R. White Jr. Jay H. Beckstead 《Journal of cutaneous pathology》1995,22(4):327-335
Juvenile xanthogranuloma (JXC) is a benign histiocylic proliferation of uncertain histogenesis which usually resolves spontaneously. Histopathologically, classic lesions are characterized by diffuse proliferations of foamy histiocytes, many of which may be multinucleated (Toulon cells), admixed with lymphocytes and eosinophils. Histologic variants of JXG, perhaps representing evolving lesions, may lack these typical histopathological features, showing diffuse infiltrates of non-foamy mononuclear histiocytes without Toulon cells, posing problems in differentiation from other histiocylic or melanocylic proliferations. Immunohistochemically, JXG is characterized by variable expressions of several histiocytic markers as well as the absence of staining for SI00 protein. To assess better the spectrum of histopathological and immunohistochemical features of JXG, we studied nine cases of classic or histologic variant of JXG. The cases were evaluated by light microscopy and with an extensive battery of antibodies. All 9 cases, regardless of their light microscopic appearance, showed markedly positive staining with histiocytic markers including CD68, HAM56, cathepsin B and vimentin, but did not stain for S100 protein. Antibodies to factor XIIIa stained positively in 8 cases while staining for other markers was variable. Our results suggest that the histiocytes in JXG lesions have macrophagic differentiation, probably representing a reactive process to an unknown stimulus. 相似文献
2.
J. R. MacDonald J. H. Beckstead E. A. Smuckler 《International journal of experimental pathology》1987,68(2):189-199
The biochemical basis of the hepatitis-like liver injury produced by D(+)-galactosamine in rats is well-established and is linked to depletion of uridine nucleotides within parenchymal cells. However, the prominent inflammatory response that accompanies this lesion in vivo has been largely overlooked as a component of the hepatic damage. This study examines the cellular components of the inflammatory infiltrate of galactosamine-induced liver injury over time using histochemical and ultrastructural techniques. By 12 h after toxin administration, the infiltrate consisted largely of neutrophils and recently-mobilized monocytes. By 24 to 48 h after the toxin, when hepatocellular necrosis was maximal, few neutrophils were found in the infiltrate. At these times, the infiltrate consisted almost exclusively of large phagocytic cells, histochemically and morphologically consistent with active tissue macrophages apparently derived from circulating monocytes. The extent of the inflammatory response to this experimental hepatotoxin suggests that effects on the generation and development of the inflammatory response should be considered for treatments reported to alter the intrinsic hepatotoxicity of galactosamine. 相似文献
3.
Ghosh D; Stewart DR; Nayak NR; Lasley BL; Overstreet JW; Hendrickx AG; Sengupta J 《Human reproduction (Oxford, England)》1997,12(5):914-920
The present study was undertaken to assess the temporal association between
the profiles of serum concentrations of oestradiol-17beta, progesterone,
chorionic gonadotrophin (CG) and relaxin in pregnancies established
naturally, and after embryo transfer, as well as in failed pregnancies in
rhesus monkeys. In naturally mated cycles (group 1) a conception rate of
75% was obtained. In group 1, the mean day of CG detection in serum was
11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day
post-ovulation. In group 2, embryo transfer to synchronous, non-mated
surrogate recipients was performed; seven embryo transfer cycles yielded
three pregnancies which were allowed to continue to term and normal infants
were delivered. In embryo transfer cycles the mean day of CG detection was
14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day
post-ovulation. A delay of about 3 days was observed in the appearance in
circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between
natural mated and embryo transfer conception cycles. Significant
differences (P < 0.05 for progesterone and P < 0.03 for oestradiol)
were obtained for the areas under the curves for progesterone and
oestradiol between days 12 and 16 in conception cycles compared with failed
pregnancies. These data provide the first observation of the normal
hormonal signals associated with maternal recognition of transferred
embryos during the peri- implantation period, and suggest that the use of
such an experimental primate embryo transfer model may help to elucidate
components of maternal and embryonic signal-response mechanisms during
embryo implantation.
相似文献
4.
We performed a randomized doubled-blind study to evaluate whether there was a benefit in delay in tourniquet deflation with intra-articular administration of morphine and bupivacaine following operative arthroscopic surgery. In 34 patients the tourniquet was deflated immediately and in 38 patients the tourniquet remained inflated for 10 min following injection. The analgesic efficacy was assessed using pain scores and the amount of supplementary analgesia required. The results demonstrate no benefit in delay in tourniquet deflation. 相似文献
5.
A case of adenocarcinoma with significant Paneth cell differentiation arising in a villoglandular polyp at the ampulla of Vater is presented. Paneth-like cells, containing distinct fuchsinophilic granules, were a prominent component of the nonglandular invasive adenocarcinoma and were also seen in the associated adenomatous polyp. Lysozyme, trichrome, and periodic acid-Schiff digest stains, and electron microscopy confirmed that the granules were lysosomal in nature. This case confirms that cells with Paneth-like features can be a significant component in invasive neoplasms and can occur at unusual sites such as the ampulla of Vater. 相似文献
6.
Diffuse malignant lymphoma with cerebriform nuclei: A B-cell lymphoma studied with monoclonal antibodies 总被引:2,自引:0,他引:2
J S Burke R A Warnke J M Connors J H Beckstead 《American journal of clinical pathology》1985,83(6):753-759
A lymph node biopsy performed on a 55-year-old woman with asymptomatic generalized lymphadenopathy revealed a diffuse, malignant lymphoma composed of small to intermediate-sized lymphocytes with cerebriform-shaped nuclei; electron microscopy confirmed the nuclear complexity. The cerebriform nuclear configuration, coupled with an interfollicular pattern of nodal involvement with encroachment upon residual germinal centers, was presumptive of either mycosis fungoides or a peripheral T-cell lymphoma. Immunologic evaluation, however, indicated that the cerebriform lymphocytes represented a monoclonal B-cell population (IgM-IgD, lambda). Staining with monoclonal antibodies disclosed a phenotype of Ia+, B1+, BA-1+, BA-2+, Leu-1+; the neoplastic cells were unreactive with T-cell, lineage-specific antibodies (anti-Leu-2a, -3a, -4, -5) and with J5 (CALLA). In light of the immunophenotype and the distributional pattern, the cerebriform-shaped lymphocytes may represent an extreme morphologic variant of intermediate lymphocytic lymphoma. 相似文献
7.
C Ahluwalia M Bernstein-Singer J Beckstead R K Brynes 《American journal of clinical pathology》1991,95(4):561-564
The authors report a case of Kaposi's sarcoma (KS) involving the bone marrow of a patient with acquired immune deficiency syndrome (AIDS). The morphologic features, differential diagnosis, immunostaining pattern, and unusually low frequency of marrow involvement by AIDS-related KS are discussed. 相似文献
8.
R M Beckstead 《Neuroscience》1988,27(3):851-863
To ascertain the cellular associations of the D1 and D2 dopamine receptor subtypes in components of the basal ganglia, cats were prepared with unilateral, axon-sparing, ibotenic acid lesions of the striatum (n = 6) or lesions of the nigrostriatal dopamine system by intranigral infusion of 6-hydroxydopamine (n = 8). After 42 days survival, tissue sections from the brains were processed for quantitative, in vitro receptor autoradiography with [3H]SCH23390 (D1 radioligand) or [3H]spiroperidol (D2 radioligand). Lesion-induced changes in basal ganglia nuclei were assessed by comparing them to the corresponding nuclei on the intact side and in naive brains. Ibotenate lesions cause a decline in specific D1 and D2 receptor-binding in the area of the striatal lesion of 94% and 85%, respectively, and completely eliminate the uneven patterns of high- and low-density binding that are characteristic of the cat's caudate nucleus. The globus pallidus, entopeduncular nucleus and pars reticulata of the substantia nigra also show marked reductions in binding after striatal ibotenate lesions. Thus, after caudate nucleus lesions, D2 binding in the two pallidal segments declines by approximately 50%, but remains unchanged in the substantia nigra. Binding of the D1 radioligand (which is not measurable in the globus pallidus) declines by about 75% in the affected regions of the entopeduncular nucleus and pars reticulata, and by about 30% in the pars compacta. Lesions of the nigral dopamine neurons reduce D2 receptor-binding by 95% in the pars compacta and 40% in the pars reticulata, but have no effect on the concentration of D1 or D2 radioligand-binding in the striatum or pallidum. Moreover, such lesions failed to alter the uneven patterns of binding in the striatum. These data suggest that most, if not all, D1 receptors in the basal ganglia are associated with cells of the striatum and their axons in the entopeduncular nucleus and substantia nigra, and likewise, a large majority of D2 receptors are associated with striatal cells and their axons in pallidal structures. Nearly all D2 receptors in the substantia nigra are associated with dopamine neurons (autoreceptors). Finally, the heterogeneous patterns of D1 and D2 receptors in the striatum are a consequence of intrinsic neuronal distributions. 相似文献
9.
急性有机磷农药中毒120例的救治 总被引:1,自引:0,他引:1
0 引言 近年来 ,我科在救治急性有机磷农药 (organophos-phorus,OP)中毒方面 ,积累了一些经验 ,现报告如下 .1 对象和方法1 .1 对象 本组 1 2 0例符合《急诊急救学》中的诊断标准 [1 ](男 2 9例 ,女 91例 ) ,年龄 1 .5~ 70岁 ,平均 2 8.6岁 .经口中毒 99例 ,经皮肤中毒 2 1例 .轻度中毒 1 5例 ,中度中毒 42例 ,重度 (含极重度 )中毒 6 3例 . 1 996年 39例 ,1 997年 43例 ,1 998年 38例 . DDV 79例 ,乐果 2 0例 ,混合性中毒 1 0例 ,水胺磷 3例 ,氧化乐果、 391 1、 1 0 5 9、对硫磷各 2例 ,敌百虫 1例 ,药名不详 1 0例 .服毒量 >2 5 … 相似文献
10.
Hydrogen peroxide inhibits gap junctional intercellular communication in glutathione sufficient but not glutathione deficient cells 总被引:7,自引:5,他引:7
Cell to cell communication via gap junctions is essential in the
maintenance of the homeostatic balance of multicellular organisms. Aberrant
intercellular gap junctional communication (GJIC) has been implicated in
tumor promotion, neuropathy and teratogenesis. Oxidative stress has also
been implicated in similar pathologies such as cancer. We report a
potential link between oxidative stress and GJIC. Hydrogen peroxide, a
known tumor promoter, inhibited GJIC in WB-F344 rat liver epithelial cells
with an I50 value of 200 microM. Inhibition of GJIC by H2O2 was reversible
as indicated by the complete recovery of GJIC with the removal of H2O2 via
a change of fresh media. Free radical scavengers, such as t-butyl alcohol,
propylgallate, and Trolox, did not prevent the inhibition of GJIC by H2O2,
which indicated that the effects of H2O2 on GJIC was probably not a
consequence of aqueous free radical damage. The depletion of intracellular
GSH reversed the inhibitory effect of H2O2 on GJIC. The treatment of
glutathione- sufficient cells with H2O2 resulted in the
hyperphosphorylation of connexin43, which is the basic subunit of the
hexameric gap junction protein, as determined by Western blot analysis.
TPA, a well-known tumor promoter, also inhibits GJIC via
hyperphosphorylation of GJIC, which is a result of protein kinase-C
activation. However, H2O2 also induced hyperphosphorylation in
GSH-deficient cells that had normal rates of GJIC. Therefore, the mechanism
of GJIC inhibition must be different from the TPA-pathway and involves GSH.
相似文献