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891.
In order to draw attention to this rather rare condition affecting all age groups, 4 cases of fibroepithelial polyps of the ureter are reported. Conservative surgery is mandatory after adequate preoperative work-up. The pathological findings, incidence and diagnostic and therapeutic modalities are discussed and some etiological factors proposed. 相似文献
892.
J P Kappelhof G F Vrensen P T de Jong J Pameyer B Willekens 《American journal of ophthalmology》1986,101(1):58-69
In two pseudophakic human eyes, obtained post mortem, Elschnig's pearls were visible biomicroscopically. One eye contained a medallion lens and the other an iridocapsular lens (implanted for 53 months and 39 months, respectively). The medallion lens was fixed to the iris but was not attached to the Soemmerring's ring. Elschnig's pearls and star-shaped cells were found on the posterior capsule in the pupillary space. One loop of the iridocapsular lens was encased in the Soemmerring's ring whereas the other was located between the iris and the lens remnants. The Elschnig's pearls were on the anterior side of the ring; only a few were in the pupillary space. Two other pseudophakic eyes with clear posterior capsules also contained small numbers of Elschnig's pearls on or just near the peripheral lens remnants. 相似文献
893.
Association between PCBs and lower embryonic weight in black-crowned night herons in San Francisco Bay 总被引:3,自引:0,他引:3
D J Hoffman B A Rattner C M Bunck A Krynitsky H M Ohlendorf R W Lowe 《Journal of toxicology and environmental health》1986,19(3):383-391
Reproductive problems, including congenital malformations, reduced hatching success, and decreased survival of hatchlings, have been observed in colonial-nesting water birds at the San Francisco Bay National Wildlife Refuge (SFBNWR). Twenty-four black-crowned night heron (Nycticorax nycticorax) eggs were collected from SFBNWR in 1983. Twelve of these were collected from separate nests when late-stage embryos were pipping, and an additional egg was randomly collected from each nest for organochlorine analysis. Overt anomalies and skeletal defects were not apparent. Embryonic weights (with partially absorbed yolk sacs removed) were 15% lower (p less than 0.05) in SFBNWR embryos compared to control embryos from the Patuxent Wildlife Research Center (PWRC). Crown-rump length and femur length were shorter for SFBNWR embryos. The geometric mean polychlorinated biphenyl (PCB) concentration in SFBNWR eggs was 4.1 ppm wet weight, with a range of 0.8-52.0 ppm. A negative correlation (r = -0.61; p less than 0.05) existed between embryonic weight and log-transformed PCB residues in whole eggs collected from the same nest at SFBNWR, suggesting a possible impact of PCBs on embryonic growth. A correlation with embryonic weight did not occur for DDE [1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene] residues. Liver microsomal aryl hydrocarbon hydroxylase activity was neither significantly elevated nor correlated with PCB, DDE, or PCB plus DDE log-transformed residues. It is unknown whether the apparent association between PCBs and lower weight is persistent through hatching. 相似文献
894.
The removal of N-linked oligosaccharides by peptide-N4-[N-acetyl-beta-glucoseaminyl]asparagine amidase (previously known as aspartoglycosylamine amidohydrolase and abbreviated N-glycanase) from the surface of blood or insect-transmissible forms of Trypanosoma cruzi markedly increased the capacity of these organisms to associate with (i.e., bind and penetrate) either mouse peritoneal macrophages or rat heart myoblasts. This effect was evidenced by a significant elevation in both the percentage of infected host cells and the average number of parasites per 100 cells. Conversely, N-glycanase treatment of either host cell markedly reduced both parameters to levels significantly below those obtained with cells mock treated with medium alone. The N-glycanase effect on the parasites was inhibited by heat inactivation of the enzyme or by the presence of fetuin, an N-glycanase substrate. The enhanced capacity of N-glycanase-treated T. cruzi to engage the host cells started to subside 2 h after the treatment, indicating the reversibility of the effect. The decreased reactivity of N-glycanase-treated macrophages or myoblasts with T. cruzi suggests that N-linked oligosaccharides on these host cells are involved in the initial phase of the cell infection process. Instead, because T. cruzi interacted more effectively with host cells after treatment with N-glycanase, parasite surface N-linked oligosaccharides would seem to interfere with the association. 相似文献
895.
896.
P A DeSimone C A Martin C B Bacdayan J S Macdonald F J Rizzo J Engelberg 《Hospital practice (Office ed.)》1986,21(1):158, 160, 165-158, 7 passim
897.
Alpha-adrenoreceptor reagents. 4. Resolution of some potent selective prejunctional alpha 2-adrenoreceptor antagonists 总被引:1,自引:0,他引:1
A P Welbourn C B Chapleo A C Lane P L Myers A G Roach C F Smith M R Stillings I F Tulloch 《Journal of medicinal chemistry》1986,29(10):2000-2003
The resolution of three 2-substituted derivatives of idazoxan is described. The enantiomers show large separations in activity in a variety of in vitro and in vivo tests, and the active isomers are all potent and selective antagonists at the alpha 2-adrenoreceptor. The significance of these results in relation to those published on the enantiomers of idazoxan and to those on optically active alpha 2-adrenoreceptor agonists is discussed. 相似文献
898.
Synthesis of Estradiol Haptens Two estradiol haptens, 4-(3β,17β-dihydroxyestran-7α-yl)butanoic acid ( 9 ) and 7α-(4-aminobutyl)-3β,17β-estradiols ( 13 ), were prepared from 19-nortestosterone by partial synthesis. The binding activity for the cytosol estrogen receptor was determined by competition against [3H]-estradiol; at a concentration of 2×10?7mol/l, compound 9 displaces 50% of [3H]-estradiol. Attached to AH-Sepharose 4B compound 9 allows the cytosol estrogen receptor from calf uterus to be concentrated 1800-fold by affinity chromatography. 相似文献
899.
E B Nelson D R Abernethy D J Greenblatt B Ameer 《British journal of clinical pharmacology》1986,22(1):111-113
Disposition of paracetamol oral elixir was determined in two male patients after administration via feeding jejunostomy and compared with four male controls who received the same dose by mouth. Area under the plasma concentration-time curve, elimination half-life, and time to maximum concentration were similar in both groups after 650 mg paracetamol elixir. The absolute amounts and ratio of paracetamol glucuronide to sulphate, the major urinary metabolites after therapeutic paracetamol doses, were similar after jejunal administration as compared to oral administration. Paracetamol is absorbed and biotransformed in a similar manner after either jejunal or oral administration. Therefore, it may be administered effectively via jejunostomy tube in patients who require this route of administration. 相似文献
900.
A survey of pediatricians in private practice in the Denver and Baltimore metropolitan areas was conducted to assess pediatricians' satisfaction with the telephone in their practices. The response rates were 84% (89/106) in Denver and 72% (90/125) in Baltimore. In both cities, 42% of the physicians were dissatisfied with their telephone systems. Dissatisfied physicians were less likely to provide a morning telephone hour (P less than .02), less likely to delegate calls to office staff (P less than .01), more likely to believe that they lacked sufficient time to handle daytime calls (P less than .0001), and more likely to be in group rather than solo practice (P less than .05). Younger age of the respondent approached, but did not reach, statistical significance in its association with dissatisfaction. 相似文献