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21.
A scoring system specific for day 3 embryos has not been extensively explored. Most IVF laboratories continue to grade embryos solely on the basis of cell number and percentage fragmentation as was traditionally done for day 2 embryos. Additional morphological features, some unique to day 3 embryos, may be useful in selecting embryos most likely to blastulate and implant. The objective of this study was to derive an embryo scoring system for day 3 transfers which is predictive of positive pregnancy outcomes. A total of 316 transferred embryos from 93 patients was recorded on videotape and evaluated. The following parameters were used to grade the embryos: cell number, fragmentation pattern (FP), cytoplasmic pitting, compaction, equal sized blastomeres, blastomere expansion and absence of vacuoles. The clinical pregnancy rate was 41.9%, with an implantation rate of 18% per embryo transferred. The mean number of embryos transferred per patient was 3.4. Three formulae were derived to score embryo quality in each transfer based on the average score of individual embryos transferred. In the first scoring system, cell number alone was used to predict pregnancy outcome. The second scoring system was based on blastomere number and the observed FP. The third scoring system utilized both blastomere number and FP but also combined this with five morphological criteria to yield a final day 3 embryo quality (D3EQ) score. We found the D3EQ score to be prognostic of pregnancy outcome. This study suggests that although cell number and FP are certainly predictors of positive pregnancy outcomes, additional parameters specific to day 3 embryos should be used to stratify a cohort of embryos further.  相似文献   
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Self-report validity of recent drug use among heroin abusers depends on many factors including the population being studied and the setting in which the study is carried out. This study was conducted by the treating physicians to assess the self-report validity of recent heroin use by heroin dependent patients in the outdoor setting using 'thin layer chromatography' (TLC) and two highly sensitive methods of urinalysis viz. 'gas liquid chromatography' (GLC) and 'high performance liquid chromatography' (HPLC). Out of seventy-six heroin dependent patients who entered the study, 64 provided urine sample on the same day. Patients' self-report about recent opiate use was found to have a moderate agreement with urinalysis report. However, it is important to validate it with urinalysis during the treatment process because a substantial proportion of patients fails to report recent opiate use. It is recommended that all drug dependence treatment centres should be equipped with a sensitive urinalysis facility. Otherwise, the outcome of the treatment process should be considered with caution.  相似文献   
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Few data exist on the etiology, presentation, prognosis, and management of fungal endophthalmitis (FE) in cancer patients. FE cases were identified by reviewing the ophthalmology reports and microbiology cultures of patients at The University of Texas M. D. Anderson Cancer Center. We retrospectively reviewed the medical records and obtained information related to malignancy, fungal infection and its management, visual outcome, and mortality. We compared FE caused by Candida spp. (CE) to FE caused by molds (ME). Of the 102 cancer patients with a fungal infection for whom an ophthalmology consult was requested, 23 met the criteria for definite (N = 6) or probable (N = 17) FE (8 with CE, 15 with ME). All of the patients with ME had hematologic malignancies, whereas half of the patients with CE had solid tumor (P = .008). Only patients with CE had a history of surgery within 30 days of FE diagnosis (38%, P = .03). Fungal pneumonia [17 (74%)] and disseminated infection [14, (61%)] were common. The most common presenting symptoms were decreased vision [16 (70%)] and ocular pain [14 (61%)]. All treated patients received systemic antifungals (combination therapy in 72% of the cases). Seven patients (30%) underwent vitrectomy. Only one patient received intraocular injection of amphotericin B along with systemic antifungals. Four-week mortality was high [13 (57%)], especially in ME (73%, P = .04). Among the eight surviving patients where visual acuity could be assessed, visual outcome improved or remained stable in five (63%). FE in cancer patients occurs in the setting of severe, frequently disseminated opportunistic mycoses, is caused predominantly by hyalohyphomycetes, and is a marker for high 4-week mortality.  相似文献   
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Effect of temperature, pH, and ions on sweet taste   总被引:1,自引:0,他引:1  
The purpose of this experiment was to determine the effects of temperature (50 degrees C and 6 degrees C), pH (pH 3.0, 4.0, 5.0, 6. 0, and 7.0) and the addition of monovalent and divalent cations (5 mM Na(+), 5 mM K(+), and 5 mM Ca(2)+ ) on the sweetness intensity ratings of sweeteners ranging widely in chemical structure. A trained panel provided intensity evaluations for prototypical tastes (sweet, bitter, sour, and salty) as well as aromatic and mouth-feel attributes. The following sweeteners were included in this experiment: three sugars (fructose, glucose, sucrose), three terpenoid glycosides (monoammonium glycyrrhizinate, rebaudioside-A, stevioside), two polyhydric alcohols (mannitol, sorbitol), two dipeptide derivatives (alitame, aspartame), two N-sulfonylamides (acesulfame-K, sodium saccharin), one sulfamate (sodium cyclamate), one protein (thaumatin), one dihydrochalcone (neohesperidin dihydrochalcone), and one chlorodeoxysugar (sucralose). Two to five levels of each sweetener reflecting a range of sweetness intensities were tested, using formulae developed by DuBois et al. The main finding from this three-part study was that temperature, pH, and ions had little effect on perceived sweetness intensity. Even when significant differences were found in the temperature study, the effects were very small.  相似文献   
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Summary Fenfluramine, an amphophilic compound which is a halogenated derivative of amphetamine, is still used as an anorectic agent for weight reduction, as it acts on the satiety center of the hypothalamus. Holtzman strain rats aged 6 days were daily injected s.c. fenfluramine hydrochloride at the dose of 75 mg/kg body weight. The animals were killed at different time intervals between days 7 and 40, and different parts of the brain were examined by light and electron microscopy. About half of the animals showed intralysosomal membrano-cytoplasmic bodies in the oligodendroglia, neurons, and neuropil, maximally in the animals receiving 8–19 injections. They were seen as concentrically arranged, single-layered lamellae; small dense bodies; or larger heterogeneous bodies. The mechanism of production of such inclusions could be the formation of complexes of this amphophilic compound with tissue phospholipids, or some enzyme-inhibiting action. A marked prominence of dark cells, predominantly oligodendroglia, was also noticed in the brains of experimental animals. Some of these cells appeared to be dark neurons, probably resulting from the serotonin-depleting effect of fenfluramine. A few dark cells were identified as resting microglial cells, while macrophagic reactive microglia were detected in the brains of very young animals. Fenfluramine appears to provide a model for studying neuroglial reactions.Paper presented at the Erwin Riesch symposium on Lysosomal Disorders of the Nervous System, Berlin (Convenor, Prof. Cervos-Navarro); and as poster-talk at the 9th International Congress of Neuropathology, Vienna, September 1982  相似文献   
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