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161.
The International Journal of Cardiovascular Imaging - Few data are available on the prevalence of right ventricle (RV) systolic dysfunction, assessed including RV strain, and RV to pulmonary artery...  相似文献   
162.
To compact the extracellular sides of myelin, an important transition must take place: from membrane sliding, while building the wraps, to membrane adhesion and water exclusion. Removal of the negatively charged glycocalyx becomes the limiting factor in such transition. What is required to initiate this membrane‐zipping process? Knocking‐out the Lipocalin Apolipoprotein D (ApoD), essential for lysosomal functional integrity in glial cells, results in a specific defect in myelin extracellular leaflet compaction in peripheral and central nervous system, which results in reduced conduction velocity and suboptimal behavioral outputs: motor learning is compromised. Myelination initiation, growth, intracellular leaflet compaction, myelin thickness or internodal length remain unaltered. Lack of ApoD specifically modifies Plp and P0 protein expression, but not Mbp or Mag. Late in myelin maturation period, ApoD affects lipogenic and growth‐related, but not stress‐responsive, signaling pathways. Without ApoD, the sialylated glycocalyx is maintained and ganglioside content remains high. In peripheral nervous system, Neu3 membrane sialidase and lysosomal Neu1 are coordinately expressed with ApoD in subsets of Schwann cells. ApoD‐KO myelin becomes depleted of Neu3 and enriched in Fyn, a kinase with pivotal roles in transducing axon‐derived signals into myelin properties. In the absence of ApoD, partial permeabilization of lysosomes alters Neu1 location as well. Exogenous ApoD rescues ApoD‐KO hypersialylated glycocalyx in astrocytes, demonstrating that ApoD is necessary and sufficient to control glycocalyx composition in glial cells. By ensuring lysosomal functional integrity and adequate subcellular location of effector and regulatory proteins, ApoD guarantees the glycolipid recycling and glycocalyx removal required to complete myelin compaction.  相似文献   
163.
BACKGROUND: Progestin-only methods are among the contraceptive options available for breastfeeding women, however the doses of progestin used in emergency contraception (EC) have not been evaluated in nursing mothers. We therefore investigated the pharmacokinetics of 1.5 mg levonorgestrel (LNG) in lactating women. METHODS: Twelve healthy exclusively breastfeeding volunteers received 1.5 mg LNG. Women refrained from nursing for 72 h after dosing and fed their infants with milk frozen beforehand. Serial blood and milk samples were collected for 120 h and assayed for LNG and sex hormone binding globulin. RESULTS: LNG concentrations peaked in plasma and in milk 1-4 h and 2-4 h after dosing, respectively. Concentrations in milk (M) paralleled those in plasma (P) but were consistently lower (mean M:P ratio 0.28). Estimated infant exposure to LNG is 1.6 microg on the day of dosing (1 microg in the first 8 h), 0.3 microg on the second day and 0.2 microg on the third day. CONCLUSIONS: Nursing mothers may need EC. These results suggest that to limit infant exposure to the period of maximum LNG excretion in milk, mothers should discontinue nursing for at least 8 h, but not more than 24 h, after EC.  相似文献   
164.
Human antibodies raised in response to human herpesvirus 7 (HHV-7) infection are directed predominantly to one or more HHV-7-infected cell proteins with apparent molecular masses of about 85 to 89 kDa. The genes that encode these proteins are unknown. However, several HHH-7 genes that possibly encode proteins in this molecular mass range have been identified. Thus, the proteins encoded by open reading frame U14 (85 kDa) and U11 (86 kDa) were expressed as recombinant proteins in bacteria. Of 13 human serum specimens that recognized the 85- to 89-kDa protein(s) of HHV-7-infected cells by immunoblotting, 12 were also reactive with recombinant pp85(U14) and 8 were reactive with p86(U11). It is concluded that (i) the HHV-7 immunodominant protein is pp85(U14) and (ii) the lack of posttranslational modifications in procaryotically expressed pp85 does not adversely affect the reactivity of human sera. Monoclonal antibody (MAb) 5E1 is an HHV-7-specific MAb directed to pp85(U14). Here, the HHV-7-specific epitope in pp85(U14) was finely mapped to the C' terminal region between amino acid residues 484 and 502. However, as indicated by the low level of reactivity of human sera with the HHV-7-specific epitope recognized by MAb 5E1, human sera recognize additional epitopes of pp85(U14) that are required for their full reactivity.  相似文献   
165.
Serologic tests play an important role in diagnosis of typhoid fever. In an effort to develop a more defined reagent for these tests, purified Salmonella enterica serovar Typhi (ST) O:1,9,12 polysaccharide was conjugated to human serum albumin (HSA), and the conjugate was purified chromatographically to yield a reagent with 2 moles ST O polysaccharide per mole HSA. In 40 patients with bacteriologically confirmed typhoid fever, significant dot immunobinding titers (> or =20,000) were present in 28 (70%) tested with 100 ng of ST O antigen-HSA (ST O-HSA) conjugate, in 38 (95%) tested with 100 ng of ST lipopolysaccharide, and in 16 (40%) tested with purified unconjugated ST O chains. In sera from 22 patients with other nontyphoid fevers, 2 (9.1%) had such reactivities with 100 ng of ST O-HSA, 1 (4.5%) had such reactivity with 100 ng of ST lipopolysaccharide (4.5%), and none reacted with 100 ng of unconjugated ST O chains. None of the 17 healthy-control sera reacted significantly with any of the ST reagents. None of the patient or control sera reacted with unconjugated HSA. The sensitivity of dot immunobinding for typhoid fever was 70% with 100 ng of ST O-HSA, somewhat lower than that with 100 ng of ST lipopolysaccharide (95%) but similar to that of the Widal H agglutination test with a > or =1/160 cutoff (74%). Specificities of these tests were 91%, 95%, and 86%, respectively. These preliminary results suggest that ST O polysaccharide-protein conjugates could provide a nontoxic, easily quality-controlled synthetic reagent for analysis of human immune responses to ST as well as for the development of new diagnostics and vaccines for typhoid fever.  相似文献   
166.
The Naval Medical Research Institute currently conducts hyperbaric research in a Man-Rated Chamber Complex (MRCC) originally installed in 1977. Significant engineering alterations to the MRCC and rusting of some of its interior sections necessitated repainting, which was completed in 1988. Great care was taken in selecting an appropriate paint (polyamide epoxy) and in ensuring correct application and curing procedures. Only very low levels of hydrocarbons were found in the MRCC atmosphere before initial pressurization after painting and curing. After pressurization, however, significant chemical contamination was found. The primary contaminants were aromatic hydrocarbons: xylenes (which were a major component of both the primer and topcoat paint) and ethyl benzene. The role that pressure played in stimulating off-gassing from the paint is not clear; the off-gassing rate was observed to be similar over a large range in chamber pressures from 1.6 to 31.0 atm abs. Scrubbing the chamber atmosphere with the chemical absorbent Purafil was effective in removing the contaminants. Contamination has been observed to slowly decline with chamber use and is expected to continue to improve with time. However, this contamination experience emphasizes the need for a high precision gas analysis program at any diving facility to ensure the safety of the breathing gas and chamber atmosphere.  相似文献   
167.
Described are the results of an international collaborative study to evaluate the use of whole blood samples spotted on filter-paper (BSP) for the detection of antibodies to human immunodeficiency virus type 1 (HIV-1). BSP samples were collected from 40 patients at risk for HIV-1 infection and tested blindly using commercially available HIV antibody test kits, either specifically manufactured or modified for this purpose. Parallel serum samples were also collected, and the antibody reactivity was defined and confirmed by Western blot. The results demonstrate that recovery of antibodies from BSP samples after elution can be comparable to that from serum. Some kits can be easily adapted to test BSP samples, while others cannot. At present, detection of HIV antibodies in BSP samples should therefore be carried out using kits specifically manufactured for this purpose or by the development of a modified protocol using a panel of BSP and their corresponding serum specimens.  相似文献   
168.
3DCT allows the solid modeling of body structures from contiguous slices. The 3D images are free to rotate on the x, y, and z axes. It is possible to evidentiate structures with various densities by means of threshold operators, which allow a 3D model of both soft tissues and bones to be obtained. Shading operations allow image quality to be improved by varying the elementary units to surface units ratio. Implemented 3D rendering reduces the spatial edges by means of anti-aliasing functions. The 3D images allow the study of the complexity of maxillofacial bony structures, and they are especially useful in both surgical planning and in postoperative follow-up. We studied 58 patients with maxillofacial diseases (34 traumatic, 14 malformations, 4 dysplastic, and 6 neoplastic). In most cases (96.5%), we obtained high-quality images, which allowed both the site and the extension of the lesions to be evaluated, together with their relationships to adjacent structures. In 65% of traumatic cases, the 4 basic views thoroughly demonstrated lesion spread, while in the extant 35% of cases cutting operations and rotatory translations were necessary. In all malformation cases a clear visualization of somatic asymmetries was obtained. In both dysplastic and neoplastic cases, the best lesion evidence was obtained in superficial lesions with cortical bone involvement. This technique was always easy and quick to perform, with no need for supplemental dose exposure to the patient.  相似文献   
169.
Antioxidant activity of a Mediterranean food product: "fig syrup"   总被引:1,自引:0,他引:1  
In this work, the efficacy of fig syrup, a Mediterranean fig derivative, as a nutraceutical supplement, was demonstrated. Fig syrup is a fruit concentrate used as a common ingredient in the preparation of typical foods, and particularly in cakes. In vitro assays were performed to determine the amount of nutraceutical ingredients, such as phenolic compounds (3.92 mg equivalent of gallic acid per g) and flavonoids (0.35 mg equivalent of catechin per g), while HPLC analyses provided specific information about the composition of antioxidants in the syrup. Furthermore, total antioxidant activity, scavenging properties against DPPH and peroxyl radicals, and the anticholinesterase activity, clearly showed the efficacy of the syrup in preventing damage induced by free radicals and, thus, the applicability of this food derivative as a nutraceutical supplement.  相似文献   
170.
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