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排序方式: 共有639条查询结果,搜索用时 15 毫秒
631.
Moritz Späth Martin Hohmann Maximilian Rohde Benjamin Lengenfelder Florian Stelzle Florian Klämpfl 《Journal of biophotonics》2021,14(4):e202000465
Multiple diseases are associated with a wide spectrum of microvascular dysfunctions, microangiopathies and microcirculation disorders. Monitoring the microcirculation could thus be useful to diagnose many local and systemic circulatory disorders and to supervise critically ill patients. Many of the scores currently available to help identify the condition of a microcirculation disorder are invasive or leave scope for interpretation. Thus, the present study aims to investigate with Monte-Carlo simulations (as numerical solutions of the radiative transfer equation) whether shifted position-diffuse reflectance imaging (SP-DRI), a non-invasive diagnostic technique, reveals information on the capillary diameter to assess the state of the microcirculation. To quantify the SP-DRI signal, the modulation parameter K is introduced. It proves to correlate almost perfectly with the capillary diameter (), making it a valid parameter for reliably assessing microcirculation. SP-DRI is emerging as an important milestone on the way to early and conveniently diagnosing microcirculation associated diseases. 相似文献
632.
《Endocrine practice》2023,29(7):509-516
ObjectiveThe cardiovascular (CV) and renal benefits of sodium-glucose cotransporter-2 inhibitors (SGLT2i) in people with type 2 diabetes are well known. However, similar beneficial effects of SGLT2i in combination with dipeptidyl peptidase-4 inhibitors (DPP4i) are unknown. It is of interest to explore a trial-level meta-analysis to fill this knowledge gap.MethodsA literature search was conducted in the PubMed and Embase databases until January 31, 2023. All CV outcome trials (CVOTs) reporting the CV and renal outcomes of SGLT2i with or without background DPP4i therapy against the placebo were retrieved. A meta-analysis was subsequently conducted by applying the inverse variance-weighted averages of pooled logarithmic hazard ratio using primarily random-effects analysis.ResultsThis meta-analysis showed that the beneficial 3-point major adverse cardiovascular events composite (3 CVOTs; N = 32 418), the composite of CV death or heart failure hospitalization (hHF) (4 CVOTs; N = 37 687), hHF (3 CVOTs; N = 27 545), CV death (4 CVOTs; N = 34 565), and renal outcomes (2 CVOTs; N = 25 406) with SGLT2i were similar with or without background DPP4i therapy against the placebo (Pheterogeneity = .71, .07, .87, .72, and .25; respectively). However, against the placebo, the summary estimates for the 3-point major adverse cardiovascular events composite, hHF, and renal outcomes were stronger with SGLT2i alone, whereas the summary estimates for CV death or hHF composite were larger with SGLT2i with background DPP4i therapy.ConclusionBeneficial CV and renal effects of SGLT2i are similar against the placebo regardless of background DPP4i therapy. 相似文献
633.
Chrisna Veldsman Marleen M. Kock Theresa Rossouw Martin Nieuwoudt Mark Maeurer Anwar A. Hoosen & Marthie M. Ehlers 《FEMS immunology and medical microbiology》2009,57(3):269-273
Tuberculosis is a life-threatening infection worldwide. Despite improvements in therapy, it results in 2 million deaths and 9 million new cases annually. This study evaluated the use of the QuantiFERON-TB GOLD enzyme-linked immunosorbent assay in a high HIV/TB burden setting in an ARV clinic at the Tshwane District Hospital, South Africa. The sensitivity and specificity of the QF assay in the clinic were 30% (9/30) and 63% (19/30), respectively, when compared with the gold standard culture results. Analysis also suggested that the sensitivity of the QuantiFERON assay is determined by a limiting patient CD4 value between 150 and 200. 相似文献
634.
Luz P. Blanco Cecilia S. Toro Jaime M. Romero Carlos A. Santiviago Guido C. Mora 《Microbiology and immunology》1997,41(12):999-1003
The immunogenic effect of Salmonella typhi OmpC porin during typhoid fever in humans was evaluated in vitro. Peripheral blood mononuclear cells from 17 patients were challenged with outer membrane preparations from Escherichia coli UH302 and UH302/pSTP2K2 strains, both lacking E. coli OmpF and OmpC porins, although UH302/pSTP2K2 expressed a plasmid-encoded S. typhi Ty2 OmpC. The mononuclear cell supernatants, immunized in vitro with OmpC antigen, derived from 10 out of 17 patients activated U937 bactericidal capacity. In contrast, the supernatants from the immunization with outer membrane preparation lacking S. typhi Ty2 OmpC induced a significantly reduced bactericidal capacity of U937 cells. This procedure should prove useful for in vitro characterization of cellular immunogens from exclusive human pathogens. 相似文献
635.
L. Magni D.M. Raimondo C. Dalla Man G. De Nicolao B. Kovatchev C. Cobelli 《Biomedical signal processing and control》2009,4(4):338-346
In this paper, the feedback control of glucose concentration in type I diabetic patients using subcutaneous insulin delivery and subcutaneous continuous glucose monitoring is considered. A recently developed in silico model of glucose metabolism is employed to generate virtual patients on which control algorithms can be validated against interindividual variability. An in silico trial consisting of 100 patients is used to assess the performances of a linear output feedback and a nonlinear state-feedback model predictive controller, designed on the basis of the in silico model. More than satisfactory results are obtained in the great majority of virtual patients. The experiments highlight the crucial role of the anticipative feedforward action driven by the meal announcement information. Preliminary results indicate that further improvements may be achieved by means of a nonlinear model predictive control scheme. 相似文献
636.
Mantovani G. Macciò A. Lai P. Turnu E. Del Giacco G. S. 《Cell biochemistry and biophysics》1994,24(1-3):301-305
The aim of the study was to evaluate the subset distribution and the IL-2 R p55–p75 subunit expression on unstimulated and
phytohemagglutinin (PHA)-stimulated (at 3-d) peripheral blood mononuclear cells (PBMC), of patients with solid cancers of
different sites. Indeed the expression of the two subunits of IL-2R is an essential prerequisite for The action of the IL-2
on CD8+, CD16+ lymphocytes as effectors in antitumor activity (LAK-cells). The subset distribution (CD3, CD4, CD8, CD16, DR) was assessed
by cytofluorometry with specific monoclonal antibodies (MAbs); the p55 (CD25) and p75 subunit expression was evaluated by
specific MAb (OKT26a and anti-p75). Ninety patients with advanced cancer (mainly non-small cell lung cancer [NSCLC], head
and neck cancer, and gynecological cancer; mean age 55 yr; range 27–80) were studied. Thirty-five age- and sex-matched healthy
subjects were studied as controls. Our data show that there is no significant difference in the subset distribution between
cancer patients and controls. Furthermore, no difference has been found in the expression of p55 subunits on unstimulated
PBMC between cancer patients and controls. No difference has been found in the expression of both p55 and p75 subunits on
PHA-stimulated PBMC between cancer patients and controls. Our results can support the rationale for further clinical trials
with IL-2 in solid malignancies. 相似文献
637.
Sissel Evy Monstad Anette Knudsen Helga B. Salvesen Jan H. Aarseth Christian A. Vedeler 《Cancer immunology, immunotherapy : CII》2009,58(11):1795-1800
Purpose We assessed the frequency and levels of onconeural antibodies in 974 patients with various types of tumours, but without apparent
paraneoplastic neurological syndromes (PNS).
Patients and methods We included patients with the following tumours: 200 small-cell lung cancer (SCLC) patients, 253 breast cancer patients, 182
ovarian cancer patients, 266 uterine cancer patients and 73 thymoma patients, as well as 52 patients with PNS and cancer and
300 healthy blood donors. Sera were screened for amphiphysin, CRMP5, Hu, Ma2, Ri and Yo antibodies using a multi-well immunoprecipitation
technique.
Results The most frequently detected antibodies were Hu followed by CRMP5. Ma2, Yo, amphiphysin and Ri antibodies were less common,
but each was found at similar frequencies. Onconeural antibodies were present at similar levels in sera from the PNS control
group and from cancer patients. Hu antibodies were rare in cancers other than SCLC. CRMP5 was the only antibody found in patients
with thymoma and this antibody was more common among patients with thymoma than in other tumour patients. With one exception,
coexisting antibodies were only found in patients with SCLC. The presence of onconeural antibodies in SCLC patients was not
associated with prolonged survival.
Conclusion Onconeural antibodies are associated with various types of tumours suggesting that all antibodies should be included in the
serological screening for possible PNS. The levels of onconeural antibody are not sufficiently sensitive to discriminate between
cancer patients with PNS and those without. 相似文献
638.
639.
Slobodan Christopher A. Jeffrey J. Rahul 《Journal of electromyography and kinesiology》2005,15(6):556-563
The purpose of the study was to evaluate a method for testing bimanual prehension based on a novel experimental device. The device consists of two handles allowing for simultaneous measurement of bimanual hand grip forces (GF) and different patterns of load forces (LF) exerted during compression and tension along the longitudinal axis. In order to assess the reliability of the obtained measures, eight healthy subjects were tested over three consecutive test, while three moderately impaired neurological patients were tested once. In healthy subjects, high coordination was observed between GFs and LFs, as well as between two GFs and two LFs. The results also suggest a satisfactory task performance in regards to exerting the instructed LF profile, as well as a sufficient, but not excessive GF. The reliability of most of the assessed variables proved to be either moderate or high. When compared to healthy subjects, the data obtained from neurological patients mainly revealed irregular patterns of LFs, excessive GFs, as well as a relatively weak relationship between GFs and LFs. It was concluded that the evaluated methodological approach can be applied not only to explore uni- and bi-manual coordination of arm and hand grip forces in various prehensile activities, but also to serve as a basis for future development of specific clinical tests for neurological patients and other populations that demonstrate impaired hand function. 相似文献