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排序方式: 共有802条查询结果,搜索用时 15 毫秒
1.
2.
We followed 18,490 infants from their first visit to a county child health clinic (CHC) in Maryland through visits through their third year of age to investigate whether their continued use of the CHCs was related to their characteristics or to the services they were provided as an infant. We classified as provided services immunization, an Early and Periodic Screening, Diagnosis, and Treatment Program (EPSDT) recommended screening, and number of visits. Immunization was associated with an increased percentage of infants who returned to the CHCs at two and three years of age. Half of the children, on the other hand, never returned to the clinics if they were not immunized as infants. These findings persisted, regardless of race, Medicaid status, completion of a screening, or number of visits in the first year of life. One-fifth of infants did not receive an immunization during one or more visits to CHCs in their first year. Failure to administer an immunization to infants appears to impede subsequent use of public health clinics for well child care. 相似文献
3.
LN Weinberger MJ Zirwas JC English III 《Journal of the European Academy of Dermatology and Venereology》2007,21(2):156-162
Male genital oedema can be defined as swelling or the appearance of swelling of the scrotum and/or the penile shaft and prepuce. Despite the various causes of genital oedema reported in the published work, a concise approach to the evaluation and management has not been sufficiently addressed. 相似文献
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The hitherto unknown 2,3-dihydro-1,4-dioxin-2-one ( 7 ) and its 3-methyl derivative 8 have been synthesized for the first time. The olefinic double bond is inserted into the saturated 1,4-dioxanone precursors 3 and 6a/b by a retro-Diels-Alder reaction in the last step of the synthesis. The 1,4-dioxanone systems of 3 and 6 are prepared by reacting a vicinal dialkoxide with α-halogenated acyl halides, thus forming the ester and the ether bond in a one-pot reaction. Monomers 7 and 8 are polymerized by cationic initiation. The resulting products undergo fragmentation to form oligomers in the presence of protic solvents, indicting that ring-opening polymerization of the δ-lactone apparently leads to polyester chain segments. 相似文献
6.
M Bjarnadottir B S Wulff M Sameni B F Sloane D Keppler A Grubb M Abrahamson 《Molecular pathology》1998,51(6):317-326
AIM: To study the cellular transport of L68Q cystatin C, the cystatin variant causing amyloidosis and brain haemorrhage in patients suffering from hereditary cystatin C amyloid angiopathy (HCCAA). METHODS: Expression vectors for wild-type and L68Q cystatin C were constructed and used to transfect mouse NIH/3T3 cells. Stable cell clones were isolated after cotransfection with pSV2neo. Clones expressing human wild-type and L68Q cystatin C were compared with respect to secreted cystatin C by enzyme linked immunosorbent assay (ELISA), and for intracellular cystatin C by western blotting and immunofluorescence cytochemistry. Colocalisation studies in cells were performed by double staining with antibodies against human cystatin C and marker proteins for lysosomes, the Golgi apparatus, or the endoplasmic reticulum, and evaluated by confocal microscopy. RESULTS: Concentrations of human cystatin C secreted from transfected NIH/3T3 cells were similar to those secreted from human cells in culture. In general, clones expressing the gene encoding L68Q cystatin C secreted slightly lower amounts of the protein than clones expressing wild-type human cystatin C. Both immunofluorescence cytochemistry and western blotting experiments showed an increased accumulation of cystatin C in cells expressing the gene encoding L68Q cystatin C compared with cells expressing the gene for the wild-type protein. The intracellularly accumulating L68Q cystatin C was insoluble and located mainly in the endoplasmic reticulum. CONCLUSIONS: The cellular transport of human cystatin C is impeded by the pathogenic amino acid substitution Leu68-->Gln. The resulting intracellular accumulation and increased localised concentration of L68Q cystatin C might be an important event in the molecular pathophysiology of amyloid formation and brain haemorrhage in patients with HCCAA. 相似文献
7.
8.
Cyclocopolymerization of two new monomers, D-mannitol 3,4-O-carbonate 1,2:5,6-bis-O-[(2-vinylphenyl)boronate] ( 2 ) and D-mannitol 3,4-O-carbonate 1,2:5,6-bis-O-[(3-vinylphenyl)boronate] ( 3 ), was investigated. While copolymers of monomer 2, which has the double bond in ortho position, do not show optical activity after splitting off the chiral D-mannitol template, optically active copolymers were obtained from monomer 3 with its double bond in meta position. The residual optical activity is due to the configuration of the main chain (main chain chirality). With the aid of circular dichroic (CD) spectra and optical rotation measurements the configuration of the (3-vinylphenyl)boronic acid diads in the copolymer chain could be determined. When methyl methacrylate (MMA) was used as comonomer, the diads possessed (R,R) configuration. The mechanism of cyclopolymerization of monomer 3, which involves a 17-membered transition state, could be explained by approximating its conformations of lowest energy with semiempirical methods (AM1). 相似文献
9.
G. Wulff W. Vesper R. Grobe-Einsler A. Sarhan 《Macromolecular chemistry and physics.》1977,178(10):2799-2816
With the aid of a chiral template molecule functional groups could be placed in a highly crosslinked polymer in such a way that they are present in a chiral cavity in a given stereochemistry. By this method methyl, resp. 4-nitrophenyl α-D -mannopyranoside-2,3; 4,6-di-O-(4-vinylphenylboronate) ( 1a , resp. 1b ) were copolymerized to macroporous polymers from which the templates methyl, resp. 4-nitrophenyl α-D -mannopyranoside ( 2a , resp. 2b ) could be split off in return. It could be shown that such polymers with two boronic acid groupings within the chiral cavity possess a good ability for the resolution of racemates of the template used. In the case of the separation of the enantiomers of 2b separation factors up to 2,27 could be obtained. The overall optical enrichment in a chromatographic separation amounted to 87%. 相似文献
10.
Yang PY Almofti MR Lu L Kang H Zhang J Li TJ Rui YC Sun LN Chen WS 《第二军医大学学报》2006,27(6):637-637
Polygonum multiflorum stilbeneglycoside (PMS) is a water-soluble fraction of Polygonum multiflorum Thunb. , one of the most famous tonic traditional Chinese medicines, that has protective effects on the cardiovascular system. The purpose of the present study is to elucidate the effects of PMS on macrophage-derived foam cell functions and the reduction of severity of atherosclerosis in hypercholesterolemic New Zealand White (NZW) rabbits. NZW rabbits were fed for 12 weeks with a normal diet, a high cholesterol diet, or a high cholesterol diet associated with irrigation with different doses of PMS (25, 50, or 100 mg/kg). Treatment of NZW rabbits fed with high cholesterol diet with 100 mg/kg PMS attenuated the increase in plasma cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and plasma triglyceride. Treatment with 50 and 100 mg/kg PMS caused 43% and 60% decrease in atherosclerotic lesioned area ratio to total surface area, respectively. In U937 foam cells, PMS could decrease the high expression of intercellular adhesion molecule (ICAM)-1 protein and the vascular endothelial growth factor (VEGF) protein levels in the medium induced by oxidized lipoprotein when analyzed by flow cytometry. The results proved that PMS is a powerful agent against atherosclerosis and that PMS action could possibly be through the inhibition of the expression of ICAM-1 and VEGF in foam cells. 相似文献