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941.
CardioVascular and Interventional Radiology - Chyluria is characterized by the presence of chyle in the urine and often presents clinically as urinary obstruction. Traditional treatments include...  相似文献   
942.

Purpose

To assess the feasibility of validating the position of the needle in groin lymph nodes using injection of ultrasound (US) contrast prior to magnetic resonance (MR) lymphangiography.

Materials and Methods

In 28 patients (average age, 52 y; 15 women, 13 men), 25G needles were placed in bilateral groin lymph nodes using US guidance outside the MR suite. The confirmation of the position of the needles in lymph nodes and efferent lymphatic flow was performed by injecting 1 mL of the US contrast agent (Lumason) mixed with 2 mL of lidocaine and observing contrast enhancement of the efferent lymphatic ducts leading to the pelvis from the lymph node. The patients were then transferred to the MR suite, and MR lymphangiography was performed.

Results

In 6 patients, the needle was repositioned due to nonvisualization of the efferent lymphatic flow toward pelvis at the first attempt. MR lymphangiogram was then performed in all patients with good opacification of the central lymphatic system. No extravasation of gadolinium contrast agent was observed.

Conclusions

Injection of US contrast to confirm the position of the needles inside the lymph nodes is a safe and effective technique. This technique can serve as a substitute for fluoroscopic confirmation of needle position, allowing performance of MR lymphangiography on any MR machine with a detachable table.  相似文献   
943.
944.
Recent intracellular and local field potential recordings from thalamic reticular (RE) neurons in vivo as well as computational modeling of the isolated RE nucleus suggest that, at relatively hyperpolarized levels of membrane potentials, the inhibitory postsynaptic potentials (IPSPs) between RE cells can be reversed and gamma-aminobutyric acid-A (GABA(A)) -mediated depolarization can generate persistent spatio-temporal patterns in the RE nucleus. Here we investigate how this activity affects the spatio-temporal properties of spindle oscillations with computer models of interacting RE and thalamocortical (TC) cells. In a one-dimensional network of RE and TC cells, sequences of spindle oscillations alternated with localized patterns of spike-burst activity propagating inside the RE network. New sequences of spindle oscillations were initiated after removal of I(h)-mediated depolarization of the TC cells. The length of the interspindle lulls depended on the intrinsic and synaptic properties of RE and TC cells and was in the range of 3-20 s. In a two-dimensional model, GABA(A)-mediated 2-3 Hz oscillations persisted in the RE nucleus during interspindle lulls and initiated spindle sequences at many foci within the RE-TC network simultaneously. This model predicts that the intrinsic properties of the reticular thalamus may contribute to the synchrony of spindle oscillations observed in vivo.  相似文献   
945.
Our recent results on the plum pox virus (PPV) epidemiology show that PPV spreads very rapidly in plum tree plantations in the contaminated areas. A clearing of the PPV-infected trees reduces significantly the spread of the virus but does not eliminate the disease. Some plum tree cultivars, hybrids and rootstocks (Scoldus, Alina, Cristi, BN 1/8Fl, BN 2Gr. etc) showing field resistance could not be infected with PPV by natural way. However, they could be infected with PPV by artificial inoculation except for the plum tree cv. Local of Dragasani and the BN 4Kr myrobalan, which proved to be immune to PPV. PPV was not transmitted through seeds in plum tree and myrobalan in the nursery. The Hyalopterus pruni aphids were found PPV-positive by an enzyme-linked immunosorbent assay (ELISA).  相似文献   
946.
The need to simulate the normal operating conditions of the human body is the key factor in every study and engineering process of bioelectronic devices designed for implantation. The Fontan procedure is an example of such a process aimed to support the human body function. It is a standard treatment method for patients with a functionally univentricular heart. However, it has significant drawbacks such as overload of the only functional heart ventricle that often leads to the necessity of the heart transplantation. In this study, we analyze the total cavopulmonary connection (TCPC) influence on the blood with and without connected auxiliary blood circulation pump. We investigate four different types of TCPC configurations, analyze blood pressure and different flow rate, study the turbulent kinetic energy distribution, and evaluate hydraulic and power losses for various cases. Finally, we calculate volumetric scalar shear stresses distribution and demonstrate the high potential of TCPC configuration with connected rotary pump as a tool for the load redistribution in the functional heart ventricle. This work is particularly relevant for improving existing TCPCs’ quality that can extend the life of Fontan patients. Moreover, it also applies to the reduction of morbidity and mortality of the patients waiting for the heart transplantation.  相似文献   
947.
The authors present results of combined treatment of 60 patients with chronic atrophic gastritis with riboxine. A favorable effect was registered on clinical symptoms, acid-forming function, ultrastructure of gastric mucosa. The above positive effects of riboxine make it useful in combined treatment of chronic atrophic gastritis.  相似文献   
948.
Bentonite, a clay with numerous industrial and consumer applications, is mined and processed in many countries of the world. Its many beneficial uses also create the potential for widespread occupational and consumer exposure. The available studies on toxicity and epidemiology indicate that the principal exposure pathway of concern is inhalation of respirable dust by occupationally exposed cohorts. Bentonite itself is probably not more toxic than any other particulate not otherwise regulated and is not classified as a carcinogen by any regulatory or advisory body, but some bentonite may contain variable amounts of respirable crystalline silica, a recognized human carcinogen. Therefore, prudent management and adherence to occupational exposure limits is appropriate. This review summarizes the literature available on production, applications, exposure, toxicity, and epidemiology of bentonite and identifies data gaps and limitations.  相似文献   
949.
Exomes of 27 Russian subjects were analyzed for the presence of medically relevant alleles, such as protein-truncating variants (PTVs) in known recessive disease-associated genes and pathogenic missense mutations included in the ClinVar database. 36 variants (24 PTVs and 12 amino acid substitutions) were identified and then subjected to the analysis in 897 population controls. 9/36 mutations were novel, however only two of them (POLH c.490delG associated with xeroderma pigmentosum variant (XPV) and CATSPER1 c.859_860delCA responsible for spermatogenic failure) were shown to be recurrent. 27 out of 36 pathogenic alleles were already described in prior genetic studies; seven of them occurred only in the index cases, while 20 demonstrated evidence for persistence in Russian population. In particular, non-random occurrence was revealed for SERPINA1 c.1096G > A (alpha-1 antitrypsin deficiency), C8B c.1282C > T and c.1653G > A (complement component 8B deficiency), ATP7B c.3207C > A (Wilson disease), PROP1 c.301_302delAG (combined pituitary hormone deficiency), CYP21A2 c.844G > T (non-classical form of adrenogenital syndrome), EYS c.1155T > A (retinitis pigmentosa), HADHA c.1528G > C (LCHAD deficiency), SCO2 c.418G > A (cytochrome c oxidase deficiency), OTOA c.2359G > T (sensorineural deafness), C2 c.839_866del (complement component 2 deficiency), ACADVL c.848T > C (VLCAD deficiency), TGM5 c.337G > T (acral peeling skin syndrome) and VWF c.2561 G > A (von Willebrand disease, type 2N). These data deserve to be considered in future medical genetic activities.  相似文献   
950.
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