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991.
Bong Hyo Lee Rong Jie Zhao Jin Young Moon Seong Shoon Yoon Jung-Ae Kim Heeduk An Young Kyu Kwon Meeyul Hwang Seong Hun Choi Insop Shim Bong Hyun Kim Chae Ha Yang 《Neuroscience letters》2008
In our previous study we demonstrated that acupuncture at Shenmen (HT7) points suppressed a decrease of accumbal dopamine (DA) release in ethanol-withdrawn rats. Furthermore, here we found that it inhibited behavioral withdrawal signs of ethanol. In an effort to better understand the mechanisms underlying this inhibition, the potential role of GABA receptor system in acupuncture was investigated. Male Sprague–Dawley rats were treated with 3 g/kg/day of ethanol (20%, w/v) or saline by intraperitoneal injection for 21 days. Following 48 or 72 h of ethanol withdrawal, acupuncture was applied at bilateral HT7 for 1 min. The selective GABAA antagonist bicuculline and the selective GABAB antagonist SCH 50911 were injected intraperitoneally 20 min before acupuncture, respectively. Importantly, suppressive effects of acupuncture on DA deficiency were completely abolished by SCH 50911, but not by bicuculline, whereas ameliorating effects of acupuncture on ethanol withdrawal syndrome were completely blocked either by SCH 50911 or bicuculline. These results suggest that acupuncture at specific acupoint HT7 may normalize the DA release in the mesolimbic system and attenuate withdrawal syndrome through the GABAB receptor system in ethanol-withdrawn rats. 相似文献
992.
Traditionally, radiology has been conceived as a support department providing patient scanning services to the other clinical
departments in a hospital. However, recent advancements in networking technology and related information systems such as picture
archiving and communication system (PACS) and radiology information system (RIS) provide new opportunities for inventing different
types of diagnostic imaging businesses such as teleradiology. In this article, we examined the business processes of currently
operating imaging centers and proposed a prototype of an information system that can facilitate their workflows in a more
efficient way. The principal component of our proposed system is a report management module built on extensible markup language
(XML) technologies that allows much flexibility and convenience for both imaging technicians and radiologists. 相似文献
993.
在休克过程中,体内活性氧代谢与细胞内钙超负荷存在着相互影响。为了研究林克和复苏过程中钙拮抗剂对脂质过氧化的影响,用17只杂种犬快速放血使平均动脉压为5.32kpd,并维持90min。然后回输全部失血。在休克30min时,各组别静脉注射(15min内)硫氮酮(40g/kg·min ̄(-1)),异搏定(10μg/kg·min ̄(-1)),或等量生理盐水。复苏后150min处死动物,取心、肝、肺、肾、胰和小肠组织备检。结果显示,用硫氮酮和异搏定治疗组,各主要脏器组织中黄嘌呤氧化酶活性和丙二醛含量均显著低于休克对照组。而各检测组织中超氧化物歧化酶活性变化不一。这些资料显示钙拮抗剂抗休克的机制与其阻滞Ca2+内流,降低组织中黄嘌呤氧化酶活性,抑制脂质过氧化有密切关系。 相似文献
994.
一个遗传性痉挛性截瘫家系的临床特点与spastin基因突变分析 总被引:1,自引:0,他引:1
目的探讨遗传性痉挛性截瘫(hereditary spastic paraplegia,HSP)一家系的临床特点及其与spastin基因突变关系。方法对整个家系进行详细的临床检查,先证者和家系内另两例患者进行了肌电图检查,先证者还进行了胸髓核磁共振检查。应用聚合酶链反应结合DNA序列分析方法,检测该家系中先证者和其父亲spastin基因的突变情况。结果家族中所有患者具有遗传性痉挛性截瘫的典型表现,先证者胸髓核磁共振成像显示胸髓明显萎缩,PCR-DNA序列分析患者spastin基因的17个外显子均未发现有异常的突变。结论该HSP家系的患者具有典型的临床表现,并非spastin基因外显子突变所致。 相似文献
995.
Chee-Kin Hui Eva Lau Helen Wu Alexander Monto Michael Kim John M Luk George K K Lau Teresa Lyn Wright 《Journal of clinical virology》2006,35(2):185-192
Occult hepatitis B virus (HBV) infection in individuals without hepatitis B surface antigen (HBsAg) can be identified in hepatitis C virus (HCV) infected patients. However, its role in fibrosis progression remains uncertain. This retrospective study compared the fibrosis progression (defined as fibrosis progression by at least one stage) and progression to severe fibrosis (fibrosis stage 3 or 4) in HCV patients with occult HBV infection. Occult HBV infection was diagnosed by the detection of HBV DNA in the serum of 74 consecutive anti-HCV positive patients by PCR. Thirty-one patients (41.9%) had occult HBV infection. All 74 patients had a median of 2 (range 2-3) liver biopsies. The median time between the first and last liver biopsy was 57.7 (range 15.0-132.8) months. Eleven of the 31 patients with occult HBV infection compared with 12 of the 43 patients without occult HBV infection had fibrosis progression (35.5% versus 27.9%, respectively, p=0.608). Six of the 31 patients with occult HBV infection compared with 8 of the 43 patients without occult HBV infection developed severe fibrosis (19.4% versus 18.6%, respectively, p=0.946). In conclusion, chronic HCV patients with occult HBV co-infection does not seem to progress more than patients without occult HBV infection. However, more large-scale studies are needed before a definite conclusion can be obtained. 相似文献
996.
X. Chen D. Yang W. Shen H.F. Dong J.M. Wang J.J. Oppenheim O.M.Z. Howard 《Inflammation research》2000,49(12):744-755
OBJECTIVE AND DESIGN: To demonstrate the role of bile acids in immune modulation we examined the ability of select bile acids to inhibit leukocyte migration and chemoattractant receptor function. MATERIALS: To elucidate this mechanism, we employed primary human monocytes, neutrophils and cell lines transfected to express either the high affinity fMLP receptor (FPR) or the low affinity fMLP receptor like 1 (FPRL1). Treatment: Cells were treated with chenodeoxycholic acid (CDCA) and related bile acids in a 0-400 micromolar range. METHOD: Cell viability, chemotaxis and calcium flux analysis were preformed. RESULTS: We observed that pathophysiological levels (< or = 150 micromolar) of CDCA competitively inhibited 3H-fMLP binding to human monocytes, FPR and FPRL1 transfected cells. Additionally, CDCA reduced both the chemotactic and calcium flux responses induced by fMLP or "W" peptide. Further, CDCA inhibited anti-FPR antibody binding to monocytes. CONCLUSIONS: CDCA selectively inhibited human leukocyte chemotaxis and calcium flux induced by fMLP, but not other chemoattractants, suggesting a mechanism for inhibition of inflammation and suppression of innate immune response. 相似文献
997.
BACKGROUND: The relation between latex-specific IgE titer and the type or total number of latex-induced symptoms has not been previously investigated. OBJECTIVE: We sought to determine the association of latex-IgE in vitro assay results with the type, number, or severity of symptoms in patients allergic to latex. METHODS: Ninety-one patients with positive histories and positive skin test responses were identified as having type I allergy. Data was collected for reported symptoms after latex exposure. Symptom severity was quantitated by 2 scores: (1) the total number of symptoms to latex exposure and (2) a symptom severity score (3 = anaphylaxis, 2 = asthma, and 1 = rhinoconjunctivitis, urticaria, or both). All subjects underwent AlaSTAT and CAP tests. RESULTS: AlaSTAT class was associated with total number of symptoms (r = 0.32, P <.001) and severity score (r = 0.33, P <.002). Similarly, CAP class was associated with both number of symptoms (r = 0.32, P <. 0001) and severity score (r = 0.31, P <.001). Among the symptoms reported, asthma had the strongest association with a positive in vitro IgE assay (odds ratio = 6.7 [95% confidence interval = 1.9, 25. 6]), followed by urticaria (odds ratio = 1.9 [95% confidence interval = 0.8, 4.6]). Contact dermatitis had no statistical association with in vitro assays in this study. AlaSTAT and CAP class correlated together significantly (r = 0.58, P <.001). CONCLUSION: Patients allergic to latex with higher AlaSTAT or CAP class were more symptomatic. Increasing class or titer also predicted more severe symptoms. Higher class of either the AlaSTAT or CAP assay to latex was strongly associated with latex-related asthma and urticaria and marginally associated with latex-related rhinoconjunctivitis. 相似文献
998.
999.
Neurofibromatosis 2 (NF2) is an inherited cancer syndrome resulting from
mutations in the NF2 tumor suppressor gene. Analysis of NF2 mutations has
revealed some general genotype-phenotype correlations. Severe disease has
been associated with mutations that produce a premature termination while
more mild disease has been associated with missense mutations. Here, we
provide experimental proof for these genotype-phenotype correlations by
demonstrating that nonsense mutations fail to produce stable merlin protein
while missense mutations result in the generation of merlin proteins
defective in negative growth regulation. This inability to suppress cell
growth may result from defects in the function of merlin at several levels,
including failure to form an intramolecular complex. Based on these
findings, we propose a model for merlin growth suppression that provides a
framework for analyzing NF2 patient mutations and merlin function.
相似文献
1000.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献