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J W Huff 《Investigative ophthalmology & visual science》1990,31(7):1288-1293
The relationship of contact lens-induced edema to epithelial and endothelial function was determined in isolated superfused rabbit corneas. Placement of a polymethyl methacrylate (PMMA) contact lens on the cornea caused swelling rates of 15-28 microns/hr compared to 0-6 microns/hr in paired control corneas. The edema increased with temperature (P less than 0.01). PMMA-induced swelling was significant in: 1) bicarbonate-free Ringer's solution; 2) chloride-free Ringer's; 3) 0.3 mM furosemide-treated corneas; and 4) deepithelialized corneas. The swelling did not occur in corneas with silicone oil replacing the endothelium to block fluid uptake. The effluent aqueous bathing fluid from edematous corneas did not induce edema in normoxic corneas. These studies demonstrate that contact lens-induced edema depends on metabolism, involves a significant stromal contribution, and requires fluid absorption across the endothelial layer, but is not a direct result of epithelial and endothelial ion transport inhibition. 相似文献
3.
P C Chan J Huff J K Haseman J A Quest W Hall 《Japanese journal of cancer research》1992,83(3):258-263
Short-term and long-term carcinogenicity of methyl carbamate (MCB) was evaluated in F344 rats and B6C3F1 mice. In experiments lasting 6, 12, and 18 months, MCB was given in water by gavage to groups of 10 male and 10 female rats at 0 or 400 mg/kg body weight, 5 days per week, and to similar groups of mice at 0 or 1,000 mg/kg. At 6 months, MCB induced atypical mitoses, cytologic alterations, cytomegaly, pigmentation, necrosis, and neoplastic nodules of the liver in rats. At 12 and 18 months, carcinomas of the liver were induced by MCB in 80-90% of male rats and in 60-80% of female rats. None was observed in control rats or in mice. In the 2-year studies, MCB was given to groups of 50 male and 50 female rats at 0, 100, or 200 mg/kg and to similar groups of mice at 0, 500, or 1,000 mg/kg, 5 days/week. Chronic focal inflammation, cytologic alteration, hyperplasia, and neoplastic nodules and carcinomas (200 mg/kg groups only) of the liver were induced by MCB in rats. Liver tumor incidence data for combined experiments in rats were: males--5% in controls, 0% in 100 mg/kg group, 14% in 200 mg/kg group, and 77% in 400 mg/kg group; females--5% in controls, 0% in controls, 0% in 100 mg/kg group, 12% in 200 mg/kg group, and 63% in 400 mg/kg group. MCB was not shown to be carcinogenic in mice. 相似文献
4.
G E Stokker A W Alberts P S Anderson E J Cragoe A A Deana J L Gilfillan J Hirshfield W J Holtz W F Hoffman J W Huff 《Journal of medicinal chemistry》1986,29(2):170-181
The syntheses of a series of 7-(3,5-disubstituted [1,1'-bephenyl]-2-yl)-3,5-dihydroxy-6-heptenoic acids and their lactones are reported. Intrinsic 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitory activity is enhanced markedly when the biphenyl moiety is substituted by chloro or methyl groups at positions 3 and 5 and a fluoro group at position 4'. These substitutions, followed by resolution, provided compounds 100(+) and 110(+) with 2.8 times the intrinsic inhibitory activity of compactin. Compound 100(+) was shown to possess the same chirality in the lactone ring as compactin by single-crystal X-ray crystallography. 相似文献
5.
M Ganguli G Ratcliff F J Huff S Belle M J Kancel L Fischer E C Seaberg L H Kuller 《Neuroepidemiology》1991,10(1):42-52
A random sample of 1,350 persons aged 65 years and older in a rural community underwent cognitive screening as part of a survey to establish a population-based registry of dementing disorders. The screening battery included the neuropsychological tests of the assessment protocol used in the National Institute on Aging multicenter Consortium to Establish a Registry for Alzheimer's Disease (CERAD). This paper reports a large body of normative neuropsychological data from this sample with members of relatively low socioeconomic status. Age, sex, and educational level were found to have statistically significant effects on test scores. The implications of these findings for the establishment of screening cutoff scores are discussed. 相似文献
6.
GP SCHWAB AL BLUM E BODNER B DALLEMAGNE K GLASER H KOOP F PACE W RÖSCH JR SIEWERT G WETSCHER 《Journal of gastroenterology and hepatology》1997,12(12):785-789
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper. 相似文献
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Time course of hypo-osmotic swellings of human spermatozoa: evidence of ordered transition between swelling subtypes 总被引:2,自引:1,他引:2
Hossain AM; Rizk B; Barik S; Huff C; Thorneycroft IH 《Human reproduction (Oxford, England)》1998,13(6):1578-1583
The hypo-osmotic swelling test (HOST or HOS test) usually takes into
consideration the total HOS response value with no emphasis either on the
value of the response subtypes or the response evaluation time. This study
investigated the time course of HOS responses and analysed their
physiological relevance. Raw semen spermatozoa and Percoll washed
spermatozoa were used in the experiment. The morphological changes in the
sperm tail were monitored by incubating the spermatozoa in the hypo-
osmotic solution for 16 different time periods. The HOS reactive
spermatozoa and the type of HOS reaction (swelling subtypes) of the samples
subjected to different duration of treatment were identified under a phase
contrast microscope. Also the fate of individual spermatozoa in a
hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed
to a hypo-osmotic solution, the motility lasted usually less than 2 min and
motility characteristics were uniquely different from that of the
spermatozoa under iso-osmotic conditions. The HOS response development was
permanent but the motility loss due to hypo-osmotic shock was reversible up
to 1 min of incubation. There was an indication of ordered transition among
the HOS swelling subtypes apparently initiating with subtype b destined to
c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and
increase, respectively, while subtype b showed abrupt initial increase and
then gradual decrease. Transition from b to g could be direct or via one or
more than one subtypes. Ultrastructure based analysis indicated that HOS
response subtypes are the apparent reflection of the differences in the
cytoskeletal assembly of the sperm tail and thus may be identifying
different physiological variants in the sperm population. These results
indicate that shorter incubation is essential to document the kinetics of
various HOS responses but the conventional HOS test misses these important
HOS features because of lengthy incubation. Since the time course of
ordered transition of HOS responses will vary more than the total HOS
response in semen of different aetiologies, the importance of HOS response
subtypes and response evaluation time should be taken into consideration
when applying HOS test.
相似文献