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1.
2.
Several cases of relapsing attacks during which the ear becomes red and patients experience a burning sensation have been reported in the literature. This combination of symptoms has been described as ‘red ear syndrome’ (RES). We report on a 7‐year‐old boy who had episodes of reddening, swelling and a burning sensation in one ear with local hyperthermia persisting for 3 years. The differential diagnosis included RES and erythromelalgia, as isolated auricular variants of erythromelalgia have been described and the symptoms are difficult to distinguish from RES. In this report, we discuss the similarities and differences between RES and erythromelalgia. 相似文献
3.
Bipolar disorder (manic depressive disease) affects 1% of the United States population. These persons suffer from prolonged episodes of extreme elation and depression. There is a significant incidence of dental pathosis and a need for dental care among these patients. The medications used for the treatment of this disease, their physiologic effects, and their interactions with the drugs used in dentistry are reviewed. 相似文献
4.
无环鸟苷亲脂性前体药物脂质体的制备及体外抗病毒活性(英文) 总被引:2,自引:0,他引:2
本文通过将无环鸟苷(acyclovir,简称ACV)2’位羟基分别与月桂酰氯或棕榈酰氯进行酯化反应,制得亲脂性前体药物无环鸟苷月桂酸酯和无环鸟苷棕榈酸酯(分别简称为C12-ACV和C16-ACV),使脂质体包封率从ACV的29.9%提高到C12-ACV的95.6%和C16-ACV的97.1%;漏泄实验表明在4℃透析60h后,一半以上的ACV从脂质体中漏泄,而C12-ACV和C16-ACV的滞留率分别为70%和80%;体外抗疱疹病毒的试验中,在最低试验浓度0.044μmol/L时,ACV不显示抗病毒活性,而C16-ACV脂质体抑制细胞病变率达75%,说明前体药物通过与脂质体脂膜的结合增加了药物的进入细胞能力,从而提高了ACV的抗病毒能力。 相似文献
5.
Allicin inhibits SDF-1alpha-induced T cell interactions with fibronectin and endothelial cells by down-regulating cytoskeleton rearrangement, Pyk-2 phosphorylation and VLA-4 expression 总被引:2,自引:0,他引:2 下载免费PDF全文
Sela U Ganor S Hecht I Brill A Miron T Rabinkov A Wilchek M Mirelman D Lider O Hershkoviz R 《Immunology》2004,111(4):391-399
Allicin, a major ingredient of fresh garlic extract that is produced during the crushing of garlic cloves, exerts various beneficial biological effects, including a broad spectrum of antimicrobial activity, antihyperlipidaemic and antihypertensive effects. However, how allicin affects the immune system is less well known, and its effect on human T cells has never been studied. Here, we examined the in-vitro effects of allicin on the functioning of T cells related to their entry to inflamed extravascular sites. We found that allicin (20-100 microm) inhibits the SDF-1alpha (CXCL12)-induced T cell migration through fibronectin (FN), and that this inhibition is mediated by the down-regulation of (i) the reorganization of cortical actin and the subsequent T cell polarization, and (ii) T cell adhesion to FN. Moreover, allicin also inhibited T cell adhesion to endothelial cells and transendothelial migration. The mechanisms underlying these inhibitory effects of allicin are associated with its ability to down-regulate the phosphorylation of Pyk2, an intracellular member of the focal adhesion kinases, and to reduce the expression of the VCAM-1- and FN-specific alpha4beta1-integrin (VLA-4). The ability of allicin to down-regulate these chemokine-induced and VLA-4-mediated T cell functions explains its beneficial biological effects in processes where T cells play an important role and suggests that allicin may be used therapeutically with chronic inflammatory diseases. 相似文献
6.
Human natural killer cells mediate killing of intracellular Mycobacterium tuberculosis H37Rv via granule-independent mechanisms 下载免费PDF全文
Brill KJ Li Q Larkin R Canaday DH Kaplan DR Boom WH Silver RF 《Infection and immunity》2001,69(3):1755-1765
Despite the continued importance of tuberculosis as a world-wide threat to public health, little is known about the mechanisms used by human lymphocytes to contain and kill the intracellular pathogen Mycobacterium tuberculosis. We previously described an in vitro model of infection of human monocytes (MN) with virulent M. tuberculosis strain H37Rv in which the ability of peripheral blood lymphocytes to limit intracellular growth of the organism could be measured. In the current study, we determined that lymphocyte-mediated killing of intracellular M. tuberculosis occurs within the first 24 h of coculture with infected MN. Natural killer (NK) cells isolated from both purified protein derivative (PPD)-positive and PPD-negative subjects were capable of mediating this early killing of intracellular H37Rv. NK cell-mediated killing of intracellular M. tuberculosis was not associated with the production of gamma interferon. Transferred supernatants of cocultured NK cells and M. tuberculosis-infected MN could not mediate the killing of intracellular M. tuberculosis, and Transwell studies indicated that direct cell-to-cell contact was required for NK cells to mediate the killing of the organism. Killing was not dependent upon exocytosis of NK cell cytotoxic granules. NK cells induced apoptosis of mycobacterium-infected MN, but neither killing of intracellular M. tuberculosis by NK cells nor NK cell-induced apoptosis of infected MN was inhibited by blocking the interaction of FasL and Fas. Thus, human NK cells may mediate killing of intracellular M. tuberculosis via alternative apoptotic pathways. 相似文献
7.
Development of hatching blastocysts from immature human oocytes following in-vitro maturation and fertilization using a co-culture system 总被引:8,自引:0,他引:8
Hwu YM; Lee RK; Chen CP; Su JT; Chen YW; Lin SP 《Human reproduction (Oxford, England)》1998,13(7):1916-1921
Recently, in-vitro maturation (IVM) of immature human oocytes recovered
from non-stimulated follicles has been applied in the treatment of
infertility. However, in previous reports, very few embryos cultured in
conventional medium have reached the expanded blastocyst stage following
in-vitro maturation and fertilization (IVM/IVF). The objective of this
study was to investigate whether the developmental competence of human
embryos following IVM/IVF could be enhanced by the use of a human ampullary
cell co-culture system. Immature human oocytes were aspirated from small
follicles at Caesarean section and then cultured in medium containing human
menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes
were randomly cultured either in conventional culture medium alone or in
the co-culture system. Of 48 embryos cultured in conventional medium alone,
all arrested at the 2-16- cell stage on day 3 after insemination. Of 46
embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at
the 2-16-cell stage. Six embryos (13%) developed to the morula stage.
Fourteen embryos (30.4%) developed to expanded blastocysts and two
blastocysts were hatching on day 7 after insemination. We conclude that
co-culture significantly enhances the development of blastocysts in embryos
resulting from IVM/IVF.
相似文献
8.
The syndrome of ectrodactyly, ectodermal dysplasia and cleft lip and palate: report of a family demonstrating a dominant inheritance pattern 总被引:1,自引:0,他引:1
The syndrome of ectrodactyly, ectodermal dysplasia and cleft lip and palate (EEC syndrome) is described in a mother and 3 of her 4 children. Autosomal dominant inheritance was suggested in this family. However, genetic heterogeneity may exist in this syndrome. The significance of associated finClings, incluCling carcinoma of the cervix uteri, lacrimal duct stenosis and urinary tract strictures in patients with ectodermal dysplasia is considered. 相似文献
9.
We studied a patient with Klippel-Feil anomaly and subclavian steal due to isolation of the right subclavian artery. Other anomalies included hypoplasia of the right clavicle and right vertebral artery, low bifurcation of the left common carotid artery and left choanal atresia. The patient was mentally retarded with corticospinal, cerebellar, and brain stem signs. The entire brain and cervical spinal cord were small; there was no central nervous system malformation, hydrocephalus, or bony impingement on neural structures. Embryologic vascular disorders have been found to be responsible for various congenital systemic and neurologic anomalies such as intestinal atresia and hydranencephaly. Subclavian artery supply disruption sequence has been hypothesized to result in Klippel-Feil, Poland, and M?bius anomalies. In this case the vertebral and facial abnormalities may well be related to anomalous subclavian and carotid supply. An embryonic vascular "steal" has been thought to cause the sirenomelia anomaly. We postulate that the subclavian steal, during the embryonic period, may have been responsible for the small size of this patient's cerebral hemispheres, brain stem, cerebellum, and cervical spinal cord. 相似文献
10.
Kaliraman V Mullen JR Fricke WM Bastin-Shanower SA Brill SJ 《Genes & development》2001,15(20):2730-2740
The RecQ DNA helicases, human BLM and yeast Sgs1, form a complex with topoisomerase III (Top3) and are thought to act during DNA replication to restart forks that have paused due to DNA damage or topological stress. We have shown previously that yeast cells lacking SGS1 or TOP3 require MMS4 and MUS81 for viability. Here we show that Mms4 and Mus81 form a heterodimeric structure-specific endonuclease that cleaves branched DNA. Both subunits are required for optimal expression, substrate binding, and nuclease activity. Mms4 and Mus81 are conserved proteins related to the Rad1-Rad10 (XPF/ERCC1) endonuclease required for nucleotide excision repair (NER). However, the Mms4-Mus81 endonuclease is 25 times more active on branched duplex DNA and replication fork substrates than simple Y-forms, the preferred substrate for the NER complexes. We also present genetic data that indicate a novel role for Mms4-Mus81 in meiotic recombination. Our results suggest that stalled replication forks are substrates for Mms4-Mus81 cleavage-particularly in the absence of Sgs1 or BLM. Repair of this double-strand break (DSB) by homologous recombination may be responsible for the elevated levels of sister chromatid exchange (SCE) found in BLM(-/-) cells. 相似文献