This system is composed of: (1) a perspective table, (2) TV camera, (3) a high-resolution image displayer, (4) a computer, (5) a laser printer The functions of this system are as follows: (1) It can perform cephalometries directly from image of X-ray film, (2) it can diagnose and analyse the deformity and provide treatment plan. This system is valuable for orthodontics and surgical orthodontics. 相似文献
Beta-interferon (IFN-β) is a promising treatment in multiple sclerosis (MS), reducing the exacerbation rate and MRI lesion burden, as well as the disease progression in relapsing-remitting MS. IFN-β was originally defined by its antiviral effects, but the interest has recently been focused on its immunomodulatory properties. Myelin basic protein (MBP) is one of several autoantigens considered to be the target for autoaggressive immune responses, which eventually might lead to the development of MS. To study in-vitro effects of IFN-β1b on MBP induced cytokine expression, mRNA for the Th1 cytokines IFN-γ and TNF-α, the Th2 related IL-4 and IL-6, the cytolytic perforin and the immune response downregulating TGF-β was measured with in situ hybridization after culture of blood mononuclear cells (MNC) in the presence and absence of MBP. Numbers of cells expressing IFN-γ, TNF-α, perforin and IL-4 mRNA were significantly suppressed after culture with 10 U/ml IFN-β1b. No such effect was seen on MBP induced IL-6 or TGF-β mRNA expression. These observations suggest that one of the major effects of IFN-β1b is the induction of a shift in the cytokine mRNA profile towards a more immunosuppressive pattern. In parallel in vitro tests, the control substance dexametasone (40 μg/ml) reduced the numbers of cells expressing mRNA for all cytokines under study with the exception of TGF-β, to an extent equal to or even more pronounced than IFN-β1b. 相似文献
Lesbianism in China has a long but usually hidden history. This paper examines the historical and literary sources of the past to illustrate the history of lesbianism and then turns to a survey of lesbianism in the China of today. As in the past, lesbianism remains more or less hidden, and comes to light only occasionally. Data for contemporary China comes from a visit to an institution for delinquent young women, recent police records, and contemporary fiction. It has only been in the past 4 or 5 years that it was possible to talk about lesbianism and most lesbians are fearful of becoming identified. 相似文献
Summary Increased neural activity of neurosecretory cells is accompanied by large increases in extracellular K+. The possibility that elevations of this ion might involve fluid redistribution and thus affect the size of the extracellular space and the relationship between pituicytes and axons in the rat neural lobe was explored using rapid freezing and freeze-substitution. Neural lobes were incubated for 15 min before freezing either in a normal medium or one containing a 10 mM increase in KCl (high KCl), a 10 mM increase in KCl balanced by an equimolar reduction in NaCl (high KCl-low NaCl), or only a 10 mM reduction in NaCl (low NaCl). A quantitative assessment of the region of good fixation was made to determine the relative fractions occupied by axons, pituicytes and the extracellular space near the neurohaemal contact zone. In addition, the percentage of basal lamina contacted by pituicytes and axons was calculated, as was the degree of enclosure of axons by pituicytes.In neural lobes incubated in normal medium, the extracellular space accounted for approximately 30% of the cross-sectional area of the neuropil and could be divided into two domains: an extended perivascular space (28–29% of total area); and a narrow (approximately 24 nm; approximately 1% of total) space between closely apposed neurosecretory processes or between these processes and pituicytes. Pituicytes occupied almost 60% of the basal lamina at the neurohaemal contact zone, while axons occupied approximately 20%. Neural lobes incubated in either the high KCl solution, or in the high KCl-low NaCl solution, exhibited a significantly reduced extracellular space, to about 20% of the total area, or a reduction from controls of about one-third. The reduction was complemented by an increased area occupied by axons plus pituicytes. In the high KCl group, the contribution of the narrow spaces (22–24 nm) between apposed processes to the total extracellular space was greatly increased. The group exposed to low NaCl showed high variability in the size of extracellular space, and was thus not significantly different from any other group. No changes in any group were observed in the enclosure of axons by pituicytes, or in the relative amounts of axon and pituicyte apposition to the basal lamina.The subsequent buffering of K+ and other ions during periods of increased neuronal activity may be affected by changes in the extracellular space, thereby influencing stimulus-secretion coupling. A shrinkage of the extracellular space and the relative increase in the narrow spaces between processes initiated by elevated K+ could also alter the diffusion properties of the neural lobe. 相似文献
Background: Investigators in the authors' laboratory previously established the critical participation of the cerulospinal noradrenergic pathway in muscular rigidity elicited by fentanyl. The identification of colocalization of glutamate with tyrosine hydroxylase in most locus ceruleus neurons suggests a role for cerulospinal glutamatergic neurotransmission in fentanyl-induced muscular rigidity. This suggestion and the subtype(s) of glutamate receptors involved were investigated here.
Methods: Electromyographic signals activated by bilateral microinjection of 2.5 micro gram fentanyl into the locus ceruleus were recorded differentially from the left sacrococcygeus dorsi lateralis muscle of adult male Sprague-Dawley rats. The effect of intrathecal administration at the lower lumbar spinal cord of various N-methyl-D-aspartate (NMDA) and non-NMDA receptor antagonists or agonists on this index of muscular rigidity was studied. Rats were under mechanical ventilation, and intravenous infusion of ketamine (30 mg [center dot] kg sup -1 [center dot] h sup -1) was maintained until 10 min before fentanyl was administered.
Results: Microinjection of fentanyl bilaterally into the locus ceruleus increased the root mean square and decreased the mean power frequency values of electromyographic signals. The efficacy of fentanyl to elicit muscular rigidity in this manner was significantly reduced by previous intrathecal administration of either 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801), D-(-)-2-amino-5-phosphonovaleric acid (AP5), or (+/- (CPP). Intrathecal administration of kainic acid or NMDA also resulted in significant electromyographic activation. 相似文献
The skeletal extracellular matrix produced by osteoblasts contains the glycoprotein fibronectin (Fn), which regulates the adhesion, differentiation, and function of osteoblasts. Fn fibrillogenesis is involved in the process of bone mineralization. Bone morphogenetic proteins (BMPs) can be isolated from organic bone matrix and are able to initiate de novo cartilage and bone formation. In this study, the effect of BMP-4 on Fn fibrillogenesis in cultured rat osteoblasts was examined. BMP-4 enhanced Fn synthesis and extracellular Fn assembly in primary cultured osteoblasts. In addition, the extracellular assembly of Fn from exogenously applied soluble human Fn was also increased by BMP-4. It has been reported that alpha5beta1 integrin is related to Fn fibrillogenesis. The synthesis of both alpha5 and beta1 integrins was upregulated by BMP-4. Immunocytochemistry showed that the clustering of alpha5 and beta1 integrins was also increased by BMP-4. BMP-4 increased fibril formation of Fn and the adhesion of osteoblasts onto Fn matrix, which was inhibited by disintegrin triflavin and Gly-Arg-Gly-Asp-Ser (GRGDS) peptide. Phosphorylation of extracellular signal-regulated kinase (ERK) and focal adhesion kinase (FAK) was increased by BMP-4. Enhancement of extracellular Fn fibrillogenesis and the mRNA expression of beta1 integrin by BMP-4 were inhibited by ERK kinase (MEK) inhibitor PD98059. These results suggest that the enhancement of extracellular Fn fibrillogenesis by BMP-4 in cultured osteoblasts is related to the increase of the synthesis of Fn and clustering of alpha5 and beta1 integrins. ERK is involved in the signaling pathway of BMP-4 in regulating Fn fibrillogenesis in osteoblasts. 相似文献
A new DRB1 allele, DRB1*0902, has been identified in an individual of the Jing ethnic minority. Its sequence was confirmed by sequencing of PCR products and clones. This allele differed by three nucleotides from DRB1*09012 at positions 157, 161 and 166, and resulted in amino acid motif substitution from VAES to DAEY. 相似文献