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排序方式: 共有3163条查询结果,搜索用时 16 毫秒
1.
AIDS and Behavior - We investigated the rate and predictors of ineffective HIV protection in men who have sex with men (MSM) taking pre-exposure prophylaxis (PrEP) in a prospective cohort study...  相似文献   
2.
Willeke  V. M.  Anderson  M. P.  Mahadevan  A.  Rojas  R.  Bhadelia  R.  Thomas  A. J.  Kasper  E. M. 《Journal of neuro-oncology》2020,147(2):247-260
Purpose

Epstein Barr virus (EBV)-associated smooth muscle tumors (SMT) in the central nervous system are rare tumors. EBV-associated SMT mainly occur in patient with compromised immune status. We report on a case of a HIV positive patient, who developed multiple EBV-SMTs, intracranially and in the spine. We systematically review the literature on the topic.

Case report

A 46 years old female with HIV was imaged for complaints of headaches for 2 years, when an intracranial lesion was found. The patient was followed with sequential MRI scans before an excision was performed 5 years later. Pathology revealed an EBV-associated SMT. Multiple other lesions appearing in the brain and in the spine over years were treated by stereotactic radiosurgery or by surgery. At the time of this report, the patient is alive under HARRT treatment without recurrence.

Methods

A systematic PRISMA guided literature research was conducted on the topic reviewing multiple databases for EBV-associated SMT located in brain or spine. We identified 52 patients from the literature and performed a pooled analysis.

Results

All patients in this cohort except one were immuno-suppressed from HIV, post-transplant therapy or because of CIS. Female predominance and a median age of 35 years was identified as was frequent multifocality. Therapeutic strategies varied but were mostly multidisciplinary with surgery.

Conclusion

Based on our results, EBV-associated SMT should be included in the differential diagnosis of intracranial lesions mimicking meningiomas in immuno-suppressed patients. Stereotactic radiosurgery can be offered as an alternate treatment option for suitable lesions. Long-term surveillance via MRI scanning is recommended for follow up.

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IntroductionLarge variability among Alzheimer's disease (AD) cases might impact genetic discoveries and complicate dissection of underlying biological pathways.MethodsGenome Research at Fundacio ACE ([email protected]) is a genome-wide study of dementia and its clinical endophenotypes, defined based on AD's clinical certainty and vascular burden. We assessed the impact of known AD loci across endophenotypes to generate loci categories. We incorporated gene coexpression data and conducted pathway analysis per category. Finally, to evaluate the effect of heterogeneity in genetic studies, [email protected] series were meta-analyzed with additional genome-wide association study data sets.ResultsWe classified known AD loci into three categories, which might reflect the disease clinical heterogeneity. Vascular processes were only detected as a causal mechanism in probable AD. The meta-analysis strategy revealed the ANKRD31-rs4704171 and NDUFAF6-rs10098778 and confirmed SCIMP-rs7225151 and CD33-rs3865444.DiscussionThe regulation of vasculature is a prominent causal component of probable AD. [email protected] meta-analysis revealed novel AD genetic signals, strongly driven by the presence of clinical heterogeneity in the AD series.  相似文献   
5.
Phase-change contrast agents (PCCAs) possess advantages over microbubble contrast agents, such as the ability to extravasate and circulate longer in the vasculature that could enhance the diagnostic capabilities of contrast-enhanced ultrasound. PCCAs typically have a liquid perfluorocarbon (PFC) core that can be vaporized into echogenic microbubbles. Vaporization of submicron agents filled with liquid PFCs at body temperature usually requires therapeutic pressures higher than typically used for diagnostic imaging, but low-boiling-point PCCAs using decafluorobutane or octafluoropropane can be vaporized using pressures in the diagnostic imaging regime. Low-boiling-point PCCAs produce a unique acoustic signature that can be separated from tissue and bubble signals to make images with high contrast-to-tissue ratios. In this work, we explore the effect of pulse length and concentration on the vaporization signal of PCCAs and a new technique to capture and use the signals to make high contrast-to-tissue ratio images in vivo. The results indicate that using a short pulse may be ideal for imaging because it does not interact with created bubbles but still produces strong signals for making images. Furthermore, it was found that capturing PCCA vaporization signals produced higher contrast-to-tissue ratio values and better depth of penetration than imaging the bubbles generated by droplet activation using conventional contrast imaging techniques. The resolution of the vaporization signal images is poor because of the low frequency of the signals, but their high sensitivity may be used for applications such as molecular imaging, where the detection of small numbers of contrast agents is important.  相似文献   
6.
Righesso  L. A. R.  Terekhov  M.  Götz  H.  Ackermann  M.  Emrich  T.  Schreiber  L. M.  Müller  W. E. G.  Jung  J.  Rojas  J. P.  Al-Nawas  B. 《Clinical oral investigations》2021,25(10):5843-5854
Clinical Oral Investigations - Micro-computed tomography (μ-CT) and histology, the current gold standard methods for assessing the formation of new bone and blood vessels, are invasive and/or...  相似文献   
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Journal of NeuroVirology - The objective of the present study was to identify the frequency of MS patients in Latin America (LATAM) that received the influenza vaccine during the most recent season...  相似文献   
10.
Compelling pieces of evidence derived from both clinical and experimental research has demonstrated the crucial contribution of diabetes mellitus (DM) as a risk factor associated with increased cancer incidence and mortality in many human neoplasms, including gastric cancer (GC). DM is considered a systemic inflammatory disease and therefore, this inflammatory status may have profound effects on the tumor microenvironment (TME), particularly by driving many molecular mechanisms to generate a more aggressive TME. DM is an active driver in the modification of the behavior of many cell components of the TME as well as altering the mechanical properties of the extracellular matrix (ECM), leading to an increased ECM stiffening. Additionally, DM can alter many cellular signaling mechanisms and thus favoring tumor growth, invasion, and metastatic potential, as well as key elements in regulating cellular functions and cross-talks, such as the microRNAs network, the production, and cargo of exosomes, the metabolism of cell stroma and resistance to hypoxia. In the present review, we intend to highlight the mechanistic contributions of DM to the remodeling of TME in GC.  相似文献   
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