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Tears of the retinal pigment epithelium (RPE) are a recognized complication of pigment epithelium detachments associated with age-related macular degeneration (ARMD). The RPE tears are often associated with a poor visual prognosis and typically do not occur with subretinal hemorrhage. We report the case of a 76-year-old man with ARMD who developed an RPE tear associated with subretinal hemorrhage, without a demonstrable subretinal neovascular membrane. Temporally, there was a marked decrease in his vision that returned to his earlier baseline visual acuity over the course of six months of observation. 相似文献
4.
Central and peripheral effects of oxytocin administration in prairie voles (Microtus ochrogaster) 总被引:3,自引:0,他引:3
The present study examined the hypothesis that oxytocin (OT) may influence female sexual behavior in prairie voles (Microtus ochrogaster). The effectiveness of OT to induce sexual behavior was tested in ovariectomized females that were injected daily with estradiol benzoate (EB, 0.02 micrograms, twice), a dose insufficient for estrus induction. On the third day females received intracerebroventricular (ICV) injections of OT (1, 300, or 1000 ng) or saline vehicle. In the presence of minimal estrogen stimulation, OT did not induce sexual receptivity, or influence autogrooming or other social interactions. The behavioral effects of OT were examined in another group of ovariectomized females that received daily oil or EB injections (10 micrograms, twice) followed on the third day by either ICV (1, 300, or 1000 ng) or intraperitoneal (IP) (1, 3, or 10 micrograms) injections of OT. Among EB-treated females, only those in confirmed estrus, prior to ICV or IP injection, were included in these studies. There was a dose-related decrease in the percentage of females that remained in behavioral estrus after ICV OT. In those females that continued to show sexual behavior, lordosis frequencies and durations were unaffected by ICV OT. Nonsexual behavior did not differ between mated females and those exhibiting OT-inhibited sexual behavior. In females that were EB-treated, autogrooming and side-by-side behavior increased after ICV OT, while there was a decline in aggression. Female sexual and nonsexual behaviors were not significantly affected by IP OT.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
S.L. Atkin A.M. Coady D. Horton N. Sutaria L. Sellars C. Walton 《Diabetic medicine》1995,12(3):267-270
A 15-year-old girl presented de novo in diabetic ketoacidosis having been comatose for 24 h (day 1). A CT scan and lumbar puncture performed on admission were normal and her conscious level slowly improved over several days. On day 7 she had central neurological signs of bilateral knee clonus and an extensor plantar response. In addition, she had developed lower motor neurological signs of an ulnar nerve palsy of the left forearm, and ulnar, median, and radial nerve palsies of the right forearm. Magnetic resonance imaging (MRI), performed on day 12, showed multiple small cerebral haematomata with appearances at least several days of age. The scattered lesions were localized particularly to the parieto-occipital region, with sparing of the basal ganglia and without cerebral oedema, a novel feature not previously described in juvenile ketoacidosis. Four months later there was minimal residual disability of her right arm. The clinical findings together with the MRI images suggested that the peripheral nerve and central lesions were temporally related, suggesting a common aetiology. However, it is likely that MRI showed cerebral lesions which may have been missed by the conventional CT scanning performed initially. 相似文献
6.
Crohn's disease of the vulva 总被引:1,自引:0,他引:1
We have reported a case of Crohn's disease of the vulva, an unusual manifestation of inflammatory bowel disease. The initial management of this condition should be medical, using antibiotics and established regimens to control gastrointestinal symptoms. Surgical therapy is appropriate when medical management fails, as it did in our patient. 相似文献
7.
Ittel TH; Steinhausen C; Kislinger G; Kinzel S; Nolte E; Sieberth HG 《Nephrology, dialysis, transplantation》1997,12(7):1369-1375
BACKGROUND: Developments in accelerator mass spectrometry (AMS) now permit
the determination of femtogram amounts of 26Al in blood and in various
tissues with good precision and free of external contamination. METHODS: In
the present study we used trace quantities of 26Al to investigate the
intestinal absorption and compartmentalization of aluminium in rats with
renal failure (Nx, 5/6 nephrectomy) and in pair- fed controls (C). Single
oral doses of 20 ng 26Al were administered to six animals in each group
and, subsequently, 24-h post-load 26Al was analysed in serum, urine, bone,
liver, and spleen by means of AMS. RESULTS: Serum concentrations of 26Al
were significantly lower in uraemic rats compared to controls, whereas
urinary excretion was comparable (Nx, 7.11 +/- 5.78 pg/day vs C, 9.46 +/-
6.10 pg/day), suggesting a higher fraction of ultrafiltrable serum 26Al in
uraemia. The target tissues of cellular transferrin-mediated 26Al uptake,
liver and spleen, tended to show a larger degree of aluminium accumulation
in controls (0.26 +/- 0.31 pg/g vs Nx, 0.14 +/- 0.10 pg/g and 0.37 +/- 0.27
pg/g vs Nx, 0.25 +/- 0.27 pg/g respectively). In contrast, in bone, a site
of extracellular aluminium deposition, 26Al concentrations were more
elevated in uraemia (1.22 +/- 0.59 pg/g vs C: 0.68 +/- 0.30 pg/g).
Estimated total 26Al accumulation in all measured target tissues was
significantly higher in uraemic rats (28.15 +/- 9.90 pg vs C: 17.03 +/-
7.03 pg) and total recovery of 26Al from tissue and urine was 26.58 +/-
6.74 pg in controls and 35.75 +/- 7.03 pg in uraemic animals, suggesting a
fractional absorption of 0.133% and 0.175% respectively. CONCLUSIONS: Our
data suggest that fractional absorption from a dietary level dose of 26Al
is about 0.13%. Compartmentalization occurs in transferrin-dependent target
tissues such as liver and spleen; however, in quantitative terms
extracellular deposition in bone is more important. Uraemia has a
significant effect on the intestinal absorption and compartmentalization of
aluminium. It enhances fractional absorption and increases subsequent
extracellular deposition of aluminium in bone. However, at the same time
uraemia does not increase transferrin-dependent cellular accumulation of
aluminium in liver and spleen.
相似文献
8.
Canal Master instruments have a short, fluted cutting area and a small flexible shaft; they may be predisposed to rapid wear and breakage. This study examined new and used files as to tip, flute, and shaft design when new and with increasing time of canal preparation. One hundred files prepared 140 curved canals. Sizes #20, #40, and #60 files were examined unused and after 1, 3, 5, and 7 min of use. Evaluation was for uniformity when new and for deterioration and breakage with usage. The smaller sizes (#20 and #40) had some inconsistencies when new and were most predisposed to wear and breakage with time. Findings suggest that smaller files could have had improved quality control by the manufacturer. Also, they should be used with caution and discarded after short times of use in small, curved canals. This should minimize instrument separation and maximize cutting efficiency. 相似文献
9.
M W Robinson D G Scott P A Bacon K W Walton J S Coppock D L Scott 《Annals of the rheumatic diseases》1989,48(6):496-501
The proteins present in 4% polyethylene glycol (PEG) precipitates of 10 normal sera and 60 samples from patients with rheumatic diseases were studied. A variety of immunochemical methods were used, including estimation of the percentages of total serum proteins precipitated by PEG, gel filtration analyses of the precipitates, and affinity chromatography with protein A and anti-immunoglobulin columns. Substantial amounts of protein were precipitated from normal sera. Many non-immunoglobulin proteins were precipitated from patients' sera, including fibronectin, haptoglobin, albumin, transferrin, and alpha 1-antitrypsin. Affinity chromatography with anti-immunoglobulin columns bound non-immunoglobulin proteins from PEG precipitates, but the protein A affinity column did not do so. The view that circulating antibody-antigen complexes alone are precipitated by 4% PEG is too simplistic; many non-immunoglobulin proteins are involved. They may either bind to immune complexes or be coprecipitated owing to non-specific protein aggregation. 相似文献
10.
Genetic diversity and molecular identification of mosquito species in the Anopheles maculatus group using the ITS2 region of rDNA. 总被引:2,自引:0,他引:2
C Walton P Somboon S M O'Loughlin S Zhang R E Harbach Y-M Linton B Chen K Nolan S Duong M-Y Fong I Vythilingum Z D Mohammed Ho Dinh Trung R K Butlin 《Infection, genetics and evolution》2007,7(1):93-102
The species diversity and genetic structure of mosquitoes belonging to the Anopheles maculatus group in Southeast Asia were investigated using the internal transcribed spacer 2 (ITS2) of ribosomal DNA (rDNA). A molecular phylogeny indicates the presence of at least one hitherto unrecognised species. Mosquitoes of chromosomal form K from eastern Thailand have a unique ITS2 sequence that is 3.7% divergent from the next most closely related taxon (An. sawadwongporni) in the group. In the context of negligible intraspecific variation at ITS2, this suggests that chromosomal form K is most probably a distinct species. Although An. maculatus sensu stricto from northern Thailand and southern Thailand/peninsular Malaysia differ from each other in chromosomal banding pattern and vectorial capacity, no intraspecific variation was observed in the ITS2 sequences of this species over this entire geographic area despite an extensive survey. A PCR-based identification method was developed to distinguish five species of the group (An. maculatus, An. dravidicus, An. pseudowillmori, An. sawadwongporni and chromosomal form K) to assist field-based studies in northwestern Thailand. Sequences from 187 mosquitoes (mostly An. maculatus and An. sawadwongporni) revealed no intraspecific variation in specimens from Thailand, Cambodia, mainland China, Malaysia, Taiwan and Vietnam, suggesting that this identification method will be widely applicable in Southeast Asia. The lack of detectable genetic structure also suggests that populations of these species are either connected by gene flow and/or share a recent common history. 相似文献