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排序方式: 共有871条查询结果,搜索用时 15 毫秒
1.
Alpha-melanocyte-stimulating hormone reduces endotoxin-induced liver inflammation. 总被引:6,自引:1,他引:5 下载免费PDF全文
H Chiao S Foster R Thomas J Lipton R A Star 《The Journal of clinical investigation》1996,97(9):2038-2044
Alpha-Melanocyte-stimulating hormone (MSH) is a potent anti-inflammatory agent in many models of inflammation, suggesting that it inhibits a critical step common to different forms of inflammation. We showed previously that alpha-MSH inhibits nitric oxide (NO) production in cultured macro-phages. To determine how alpha-MSH acts in vivo, we induced acute hepatic inflammation by administering endotoxin (LPS) to mice pretreated with Corynebacterium parvum, alpha-MSH prevented liver inflammation even when given 30 min after LPS administration. To determine the mechanisms of action of alpha-MSH, we tested its influence on NO, infiltrating inflammatory cells, cytokines, and chemokines. Alpha-MSH inhibited systemic NO production, hepatic neutrophil infiltration, and increased hepatic mRNA abundance for TNF alpha, and the neutrophil and monocyte chemokines (KC/IL-8 and MCP-1). We conclude that alpha-MSH prevents LPS-induced hepatic inflammation by inhibiting production of chemoattractant chemokines which then modulate infiltration of inflammatory cells. Thus, alpha-MSH has an effect very early in the inflammatory cascade. 相似文献
2.
Xian ZH Zhang SH Cong WM Wu WQ Wu MC 《第二军医大学学报》2005,26(11):1320-1320
BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most prevalent fatal cancers in the world. Despite advances in early diagnosis and improvements in surgical techniques, the survival of patients with HCC even after resection is poor because of the high incidence of recurrences. Therefore, the identification of prognostic factors may be helpful in the development of new treatment protocols. AIMS: To investigate HER-2/neu status in HCC by immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH), and to explore the possibility of using trastuzumab in the treatment of HCC. METH ODS: Eight hundred and sixty eight surgical samples from patients with primary HCC were examined for their HER-2/neu status. IHC for HER-2/neu was performed with the HercepTest kit; FISH analysis was performed with the PathVysion HER-2 DNA probe kit. The correlations between HER-2/neu overexpression and clinicopathological characteristics were analysed statistically. RESULTS: HER-2/neu overexpression was detected in 21 (2.42%) of the 868 primary HCCs. Only one specimen showed HER-2/neu gene amplification by FISH. No significant associations were found between HER-2/neu overexpression and the clinicopathological parameters. CONCLUSIONS: There is a low frequency of HER-2/neu overexpression/amplification in HCC. There appears to be no role for HER-2/neu as a prognostic marker and no benefit of anti-HER-2/neu trastuzumab treatment in patients with HCC. 相似文献
3.
4.
Capacitively coupled electrical stimulation of bovine growth plate chondrocytes grown in pellet form 总被引:1,自引:0,他引:1
Pellets formed from isolated bovine growth plate chondrocytes were grown in various capacitively coupled electrical fields. The signals chosen were 0, 10, 100, 250, 500, 750, 1,000, and 1,500 V peak-to-peak, 60 kHz. The effect on cell proliferation and matrix production of these different voltages was determined by [3H]thymidine and [35S]sulfate uptake, respectively, Cyclic AMP assays were done to determine if increases in either thymidine or sulfate uptake were associated with changes in cAMP levels. Significantly increased cell proliferation occurred at 500, 750, and 1,000 V peak to peak. The calculated electric fields were 1.5 to 3.0 x 10(-2) V/cm. Proliferation was significantly inhibited at 1,500 V peak-to-peak with a calculated field of 4.5 x 10(-2) V/cm. Little if any change was seen in cAMP levels at 30 or 60 min following application of the appropriate electric signals. 相似文献
5.
S T Flock S L Jacques B C Wilson W M Star M J van Gemert 《Lasers in surgery and medicine》1992,12(5):510-519
Intralipid is an intravenous nutrient consisting of an emulsion of phospholipid micelles and water. Because Intralipid is turbid and has no strong absorption bands in the visible region of the electromagnetic spectrum, and is readily available and relatively inexpensive, it is often used as a tissue simulating phantom medium in light dosimetry experiments. In order to assist investigators requiring a controllable medium that over a finite range of wavelengths is optically equivalent to tissue, we have compiled previously published values of the optical interaction coefficients of Intralipid, most of which were measured at a wavelength of 633 nm. We have extended the measurements of the absorption and reduced scattering coefficients from 460 to 690 nm and the total attenuation coefficient from 500 to 890 nm. These measurements show that, for stock 10% Intralipid, the absorption coefficient varies from 0.015 to 0.001 cm-1 between 460 and 690 nm, the reduced scattering coefficient varies from 92 to 50 cm-1 between 460 and 690 nm, the total attenuation coefficient varies from 575 to 150 cm-1 between 500 and 890 nm, and the average cosine of scatter varies from 0.87 to 0.82 between 460 and 690 nm. With these data, we discuss the design of an optically tissue-equivalent phantom consisting of Intralipid and black India ink. 相似文献
6.
BACKGROUND: The WHO Foundation Collaborating Centre for International Drug Monitoring (Uppsala Monitoring Centre [UMC]) has received many individual case safety reports (ICSRs) associating HMG-CoA reductase inhibitor drug (statin) use with the occurrence of muscle damage, including rhabdomyolysis, and also peripheral neuropathy. A new signal has now appeared of disproportionally high reporting of upper motor neurone lesions. AIM AND SCOPE: The aim of this paper is to present the upper motor neurone lesion cases, with other evidence, as a signal of a relationship between statins and an amyotrophic lateral sclerosis (ALS)-like syndrome. The paper also presents some arguments for considering that a spectrum of severe neuromuscular damage may be associated with statin use, albeit rarely. The paper does not do more than raise the signal for further work and analysis of what must be regarded as a potentially very serious and perhaps avoidable or reversible adverse reaction, though it also suggests action to be taken if an ALS-like syndrome should occur in a patient using statins. METHODS: The 43 reports accounting for the disproportional reports in Vigibase (the database of the WHO Programme for International Drug Monitoring) are summarised and analysed for the diagnosis of an ALS-like syndrome. The issues of data quality and potential reporting bias are considered. RESULTS: 'Upper motor neurone lesion' is a rare adverse event reported in relationship to drugs in Vigibase (a database containing nearly 4 million ICSRs). Of the total of 172 ICSRs on this reported term, 43 were related to statins, of which 40 were considered further: all but one case was reported as ALS. In 34/40 reports a statin was the sole reported suspected drug. The diagnostic criteria were variable, and seven of the statin cases also had features of peripheral neuropathy. Of a total of 5534 ICSRs of peripheral neuropathy related to any drug in Vigibase, 547 were on statins. The disproportional reporting of statins and upper motor neurone lesion persisted after age stratification, and such disproportionality was not seen for statins and Parkinson's disease, Alzheimer's disease, extrapyramidal disorders, or multiple sclerosis-like syndromes. DISCUSSION: Because the cases were sometimes atypical we propose the use of the term 'ALS-like syndrome' and speculate whether this is part of a spectrum of rare neuromuscular damage. The diagnosis of ALS is often problematic, and the insidiousness and chronicity of the disease make causality with a drug difficult to assess. The disproportionally high reporting makes this an important signal nevertheless, since ALS is serious clinically and statins are so widely used. Wide use of the statins also makes a chance finding more probable, but is unlikely to cause disproportional reporting when there are no obvious biases identified. CONCLUSION: We emphasise the rarity of this possible association, and also the need for further study to establish whether a causal relationship exists. We do advocate that trial discontinuation of a statin should be considered in patients with serious neuromuscular disease such as the ALS-like syndrome, given the poor prognosis and a possibility that progression of the disease may be halted or even reversed. 相似文献
7.
Real-time imaging of Rab3a and Rab5a reveals differential roles in presynaptic function 总被引:2,自引:0,他引:2
We investigated the roles of two Rab-family proteins, Rab3a and Rab5a, in hippocampal synaptic transmission using real-time fluorescence imaging. During synaptic activity, Rab3a dissociated from synaptic vesicles and dispersed into neighbouring axonal regions. Dispersion required calcium-dependent exocytosis and was complete before the entire vesicle pool turned over. In contrast, even prolonged synaptic activity produced limited dispersion of Rab5a. A GTPase-deficient mutant, Rab3a (Q81L), dispersed more slowly than wild-type Rab3a, and decreased the rate of exocytosis and the size of the recycling pool of vesicles. While overexpression of Rab3a did not affect vesicle recycling, overexpression of Rab5a reduced the recycling pool size by 50%. We propose that while Rab3a preferentially associates with recycling synaptic vesicles and modulates their trafficking, Rab5a is largely excluded from recycling vesicles. 相似文献
8.
The t(X;1)(p11.2;q21.2) translocation in papillary renal cell carcinoma fuses a novel gene PRCC to the TFE3 transcription factor gene 总被引:4,自引:2,他引:4
9.
Catt SL; Sakkas D; Bizzaro D; Bianchi PG; Maxwell WM; Evans G 《Molecular human reproduction》1997,3(9):821-825
Controlling the sex of offspring by the separation of X and Y
chromosome-bearing spermatozoa using flow cytometry has been reported as a
clinical technique aiding prevention of X-linked diseases. Although this
technique has resulted in several hundred normal births in animals and at
least one human birth, there is still concern over its genetic safety due
to the involvement of two potentially mutagenic agents: UV light and the
fluorochrome dye, Hoechst 33342 (H33342). Human spermatozoa, particularly
those considered abnormal, may be more likely to suffer DNA damage
following exposure to mutagenic agents, compared with other mammalian
species. The stability of normal fresh and decondensed human spermatozoa
were examined after exposure to a range of levels of UV and H33342
staining, using an assay that detects endogenous nicks in the DNA of
spermatozoa. The stability of abnormal and normal, fresh and frozen-thawed
human spermatozoa was examined following UV laser, H33342 staining and flow
cytometry treatments utilizing the same assay. There was an increase in the
presence of endogenous nicks when spermatozoa were decondensed compared
with fresh spermatozoa. There was no increase in the incidence of nicks in
any group of spermatozoa after UV and fluorochrome exposure compared with
controls without exposure.
相似文献
10.
Christian B. Ong Chad A. Krueger Andrew M. Star 《The Journal of arthroplasty》2021,36(8):2658-2664.e2
BackgroundMedically complex patients require more resources and experience higher costs within total joint arthroplasty (TJA) bundled payment models. While risk adjustment would be beneficial for such patients, no tool currently exists which can reliably identify these patients preoperatively. The purpose of this study is to determine if the Hospital Frailty Risk Score (HFRS) is a valid predictor of high-TJA treatment costs.MethodsRetrospective analysis was performed on patients who underwent primary TJA between 2015 and 2020 from a single large orthopedic practice. ICD-10 codes from an institutional database were used to calculate HFRS. Cost data including inpatient, postacute, and episode of care (EOC) costs were collected. Charlson comorbidity index, demographics, readmissions, and complications were analyzed.Results4936 patients had a calculable HFRS and those with intermediate and high scores experienced more frequent readmissions/complications after TJA, as well as higher EOC costs. However, HFRS did not reliably predict EOC costs, yielding a sensitivity of 49% and specificity of 66%. Multivariate analysis revealed that both patient age and sex are superior individual cost predictors when compared with HFRS. Secondary analyses indicated that HFRS more effectively predicts TJA complications and readmissions but is still nonideal for clinical applications.ConclusionHFRS has poor sensitivity as a predictor of high-EOC costs for TJA patients but has adequate specificity for predicting postoperative readmissions and complications. Further research is needed to develop a scale that can appropriately predict orthopedic cost outcomes. 相似文献