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排序方式: 共有6071条查询结果,搜索用时 31 毫秒
201.
Andersson J Sanchez J Ekdahl KN Elgue G Nilsson B Larsson R 《Journal of biomedical materials research. Part A》2003,67(2):458-466
Contact between blood and a biomaterial surface takes place in many applications and is known to activate the coagulation and complement systems. Heparin surface coatings have been shown to reduce blood activation upon contact with artificial surfaces. To establish the optimal heparin surface concentration, blood was incubated in a tubing loop model at 37 degrees C. The tubing was coated with different surface concentrations of heparin and rotated at three different velocities. We demonstrate that the blood compatibility of a surface with regard to coagulation, complement, and platelet activation can be improved by increasing the heparin surface concentration in the 6-12 pmol antithrombin/cm2 concentration interval. The binding of factor H is not influenced by the increased heparin surface concentration, suggesting that this factor is not the primary regulator of complement on heparin surfaces. In addition, the heparin coating has no effect on the complement activation that occurs on gas surfaces in extracorporeal circuits. 相似文献
202.
Gonzalez LO Corte MD Vazquez J Junquera S Sanchez R Viña A Rodriguez JC Lamelas ML Vizoso F 《Histopathology》2008,53(4):403-415
Aims: To analyse the expression of metalloproteinases (MMPs) and their inhibitors (TIMPs) in ductal carcinoma in situ of the breast (DCIS). Methods and results: An immunohistochemical study was performed in 56 patients with pure DCIS, in 39 with DCIS adjacent to invasive carcinoma (IDC) and 63 patients with T1 IDC, using tissue microarrays and specific antibodies against MMPs and TIMPs. Immunohistochemical results were categorized using a specific software program. The data were analysed by unsupervised hierarchical cluster analysis by each cellular type. IDC showed a higher expression rate of MMP‐7 and TIMP‐1 than pure DCIS, as well as a higher expression rate of MMP‐9 and TIMP‐3 than the DCIS component of mixed cases, whereas pure DCIS showed a higher rate of expression of MMP‐9 and ‐11 and TIMP‐3 than in the DCIS component of mixed cases. Pure DCIS with a periductal inflammatory infiltrate showed significantly higher MMP‐2, ‐14 and TIMP‐1. Dendograms identified two cluster groups with distinct MMP/TIMP expression profiles in neoplastic cells and fibroblastic or mononuclear inflammatory cells surrounding the neoplastic ducts of pure DCIS. Conclusions: The results indicate the distinct variability in MMP/TIMP expression by DCIS, which may be of potential biological and clinical interest in breast cancer. 相似文献
203.
Mitnick CD Shin SS Seung KJ Rich ML Atwood SS Furin JJ Fitzmaurice GM Alcantara Viru FA Appleton SC Bayona JN Bonilla CA Chalco K Choi S Franke MF Fraser HS Guerra D Hurtado RM Jazayeri D Joseph K Llaro K Mestanza L Mukherjee JS Muñoz M Palacios E Sanchez E Sloutsky A Becerra MC 《The New England journal of medicine》2008,359(6):563-574
204.
Garcia-Portilla MP Saiz PA Fonseca E Al-Halabi S Bobes-Bascaran MT Arrojo M Benabarre A Goikolea JM Sanchez E Sarramea F Bobes J 《The journal of sexual medicine》2011,8(5):1371-1382
IntroductionSexual dysfunction in patients with severe mental disorders is often underestimated or overlooked by psychiatrists. A brief and valid self-report instrument for assessing sexual functioning may well contribute to changing this situation.AimsTo validate the Short Form of the Changes in Sexual Functioning Questionnaire (CSFQ-14) in Spanish patients with severe mental disorders.MethodsNaturalistic, cross-sectional, multicenter, validation study. Eighty-nine patients with schizophrenia and 82 with bipolar disorder were evaluated using the CSFQ-14, the Visual Analogue Scale for Sexual Functioning Satisfaction (VAS-SFS), and the Clinical Global Impression—Severity scales for mental disorders (CGI-S) and for Sexual Dysfunction (CGI-SSD).Main Outcome MeasuresThe 14-item Changes in Sexual Functioning Questionnaire.ResultsInternal reliability (Cronbach's alpha) = 0.90. Construct validity = 3 principal components, of which the first, arousal-orgasm, explained 46.4% of the total variance. Convergent validity: Pearson correlation coefficients between CSFQ-14 and VAS-SFS = 0.33 (P < 0.01) and between CSFQ-14 and CGI-SDS = ?0.71 (P < 0.01). Discriminant validity: The CSFQ-14 was able to discriminate among patients with no, mild, moderate, and severe sexual dysfunction according to CGI-SDS scores, both in males (P < 0.001) and females (P < 0.001). In males, the area under the curve (AUC) was 0.833 and a cutoff point of 49 provided a sensitivity of 92.9% and a specificity of 59.5%. In females, the AUC was 0.834 and a cutoff point of 43 provided a sensitivity of 91.9% and a specificity of 62.5%.ConclusionThe Spanish version of the CSFQ-14 is a reliable and valid instrument for assessing sexual functioning in patients with severe mental disorders. As a brief, self-rated instrument, the CSFQ-14 scale seems to be appropriate for use in everyday clinical practice as a means of identifying and monitoring changes in sexual functioning. Garcia-Portilla MP, Saiz PA, Fonseca E, Al-Halabi S, Bobes-Bascaran MT, Arrojo M, Benabarre A, Goikolea JM, Sanchez E, Sarramea F, and Bobes J. Psychometric properties of the Spanish version of the Changes in Sexual Functioning Questionnaire Short-Form (CSFQ-14) in patients with severe mental disorders. 相似文献
205.
Paternal isodisomy of chromosome 5 in a patient with recessive multiple epiphyseal dysplasia 下载免费PDF全文
206.
Roney?Santos?CoimbraEmail author Bruno?Frederico?Aguilar?Calegare Talitah?Michel?Sanchez?Candiani Vania?D’Almeida 《BMC clinical pathology》2014,14(1):43
Background
Acute bacterial meningitis frequently causes cortical and hippocampal neuron loss leading to permanent neurological sequelae. Neuron death in acute bacterial meningitis involves the excessive activation of NMDA receptors and p53-mediated apoptosis, and the latter is triggered by the depletion of NAD?+?and ATP cellular stores by the DNA repair enzyme poly(ADP-ribose) polymerase. This enzyme is activated during acute bacterial meningitis in response to DNA damage induced, on its turn, by reactive oxygen and nitrogen species. An excess of homocysteine can also induce this cascade of events in hippocampal neurons.The present work aimed at investigating the possible involvement of homocysteine in the pathophysiology of meningitis by comparing its concentrations in cerebrospinal fluid (CSF) samples from children with viral or acute bacterial meningitis, and control individuals.Methods
Homocysteine and cysteine concentrations were assessed by high-performance liquid chromatography in CSF samples from nine patients with acute bacterial meningitis, 13 patients with viral meningitis and 18 controls (median age: 4 years-old; range: <1 to 13) collected by lumbar puncture at admission at the Children's Hospital Joao Paulo II - FHEMIG, from January 2010 to November 2011.Results
We found that homocysteine accumulates up to neurotoxic levels within the central nervous system of patients with acute bacterial meningitis, but not in those with viral meningitis or control individuals. No correlation was found between homocysteine and cysteine concentrations and the cerebrospinal fluid standard cytochemical parameters.Conclusions
Our results suggest that HCY is produced intrathecally in response to acute bacterial meningitis and accumulates within the central nervous system reaching potentially neurotoxic levels. This is the first work to propose a role for HCY in the pathophysiology of brain damage associated with acute bacterial meningitis.207.
Philip M. Grant Lauren Komarow Alejandro Sanchez Fred R. Sattler David M. Asmuth Richard B. Pollard 《HIV clinical trials》2014,15(4):133-139
Background: In the pre–antiretroviral therapy (ART) era, markers of increased disease severity during an acute opportunistic infection (OI) were associated with mortality. Even with ART, mortality remains high during the first year after an OI in persons with advanced HIV infection, but it is unclear whether previous predictors of mortality remain valid in the current era. Objective: To determine clinical and immunological predictors of death after an OI. Methods: We used clinical data and stored plasma from ACTG A5164, a multicenter study evaluating the optimal timing of ART during a nontuberculous OI. We developed Cox models evaluating associations between clinical parameters and plasma marker levels at entry and time to death over the first 48 weeks after the diagnosis of OI. We developed multivariable models incorporating only clinical parameters, only plasma marker levels, or both. Results: The median CD4+ T-cell count in study participants at baseline was 29 cells/µL. Sixty-four percent of subjects had Pneumocystis jirovecii pneumonia (PCP). Twenty-three of 282 (8.2%) subjects died. In univariate analyses, entry mycobacterial infection, OI number, hospitalization, low albumin, low hemoglobin, lower CD4, and higher IL-8 and sTNFrII levels and lower IL-17 levels were associated with mortality. In the combined model using both clinical and immunologic parameters, the presence of an entry mycobacterial infection and higher sTNFrII levels were significantly associated with death. Conclusions: In the ART era, clinical risk factors for death previously identified in the pre-ART era remain predictive. Additionally, activation of the innate immune system is associated with an increased risk of death following an acute OI. 相似文献
208.
Yeranddy A. Alpizar Brett Boonen Maarten Gees Alicia Sanchez Bernd Nilius Thomas Voets Karel Talavera 《Pflügers Archiv : European journal of physiology》2014,466(3):507-515
The powerful plant-derived irritant allyl isothiocyanate (AITC, aka mustard oil) induces hyperalgesia to heat in rodents and humans through mechanisms that are not yet fully understood. It is generally believed that AITC activates the broadly tuned chemosensory cation channel transient receptor potential cation channel subfamily A member 1 (TRPA1), triggering an inflammatory response that sensitizes the heat sensor transient receptor potential cation channel subfamily V member 1 (TRPV1). In the view of recent data demonstrating that AITC can directly activate TRPV1, we here explored the possibility that this compound sensitizes TRPV1 to heat stimulation in a TRPA1-independent manner. Patch-clamp recordings and intracellular Ca2+ imaging experiments in HEK293T cells over-expressing mouse TRPV1 revealed that the increase in channel activation induced by heating is larger in the presence of AITC than in control conditions. The analysis of the effects of AITC and heat on the current–voltage relationship of TRPV1 indicates that the mechanism of sensitization is based on additive shifts of the voltage dependence of activation towards negative voltages. Finally, intracellular Ca2+ imaging experiments in mouse sensory neurons isolated from Trpa1 KO mice yielded that AITC enhances the response to heat, specifically in the subpopulation expressing TRPV1. Furthermore, this effect was strongly reduced by the TRPV1 inhibitor capsazepine and virtually absent in neurons isolated from double Trpa1/Trpv1 KO mice. Taken together, these findings demonstrate that TRPV1 is a locus for cross sensitization between AITC and heat in sensory neurons and may help explaining, at least in part, the role of this channel in AITC-induced hyperalgesia to heat. 相似文献
209.
André C Perrin-Fayolle M Grosclaude M Couturier P Basset D Cornillon J Piperno D Girodet B Sanchez R Vallon C Bellier P Nasr M 《International archives of allergy and immunology》2003,131(2):111-118
BACKGROUND: There is a growing consensus on the benefits of sublingual-swallow immunotherapy in the treatment of allergic diseases. METHODS: This randomized, double-blind placebo-controlled study was undertaken to assess the efficacy and safety of sublingual immunotherapy with standardized ragweed pollen extract tablets, in patients with an allergic rhinitis. A total of 110 outpatients were randomized (immunotherapy [I]: 55; placebo [P]: 55), of whom 99 were analyzable for efficacy (I: 48; P: 51) and 106 analyzable for safety (I: 53; P: 53). After a 28-day progression phase, the patients received a maintenance treatment during 6.5 months. Efficacy variables included a global assessment of efficacy (patient/ investigator), symptoms and medication scores as well as the frequency of asthma attacks. RESULTS: In the active treatment group, 43 patients completed the study, versus 49 on placebo. During the whole period of pollination, the difference favoring immunotherapy was highly significant for the global assessment by the patient (p = 0.004) and by the investigator (p = 0.005). Adverse reactions were reported more often in the active treatment but mild or moderate, and they abated after dose adjustment. A subgroup analysis of those patients receiving the highest dose of immunotherapy (3 tablets 3 times a week) showed a highly significant response for rhinitis and conjunctivitis total scores by comparison to lower dosages. CONCLUSION: This study confirms the efficacy and safety of sublingual immunotherapy and strongly suggests a dose-response relationship. 相似文献
210.