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1.
In this study a new computerized approach and linear models (LMs) to solve the UV/vis spectroscopy interference effects of beta-carotene with lycopene analysis by neural networks (NNs) are considered. The data collected (absorbance values) obtained by UV/vis spectrophotometry were transferred into an NN-trained computer for modeling and prediction of output. Such an integrated NN/UV/vis spectroscopy approach is capable of estimating beta-carotene and lycopene concentrations with a mean prediction error 50 times lower than that calculated by the LM/UV/vis spectroscopy approach (without any previous physicochemical knowledge of the process to be modeled).  相似文献   
2.
The aim was to study the effects of flutamide on cell proliferation, in vivo tumour growth and steroid production in canine and human IBC cell lines. IPC‐366 and SUM149 cell cultures were exposed to flutamide concentrations for 72 hours. Additionally, IPC‐366 and SUM149 xenotransplanted mice were treated subcutaneously with flutamide 3 times a week for 2 weeks. Steroid hormones determination in culture media, serum and tumour homogenates (pregnenolone, progesterone, androstenedione, testosterone, dihydrotestosterone, 17β‐oestradiol and oestrone sulphate) were assayed by EIA. in vitro cell proliferation percentages showed a decrease in all flutamide dosages in IPC‐366 and SUM149. in vivo flutamide reduced tumour size by 55% to 65%, and metastasis rates decreased. In treated groups, androgen levels in culture media, serum and tumour homogenates were increased as oestrogen levels decreased. These results suggest that flutamide treatment inhibits cell proliferation and promotes tumour reduction by increasing androgen levels and also support future therapy approaches.  相似文献   
3.
The chromosomes of sexual diploid plants of Paspalum simplex were colchicine-doubled and the plant obtained were crossed with their aposporous natural tetraploid counterparts to generate a F1 population segregating for apomixis. Analysis of the DNA content during megagametogenesis indicated that although the nuclei of nucellus and developing embryo sacs were in both the G1 and G2 phases, polar nuclei and egg cells of mature embryo sacs tended to remain in the G1 phase. Because both meiotic and aposporous mature embryo sacs are of the 8-nucleated-type in P. simplex and are barely distinguishable, nuclear DNA content of polar nuclei was used to distinguish apomictic and sexual phenotypes and confirmation obtained by progeny testing. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
4.
Background: Feline ureteral obstructions have emerged as a common problem. Ureteral strictures rarely are reported as a cause and the predisposing factors and clinical course of this condition have not been described. Objectives: Evaluate cases of feline ureteral strictures and characterize historical features, clinical signs, diagnostic imaging, surgical and endoscopic findings, histopathology, treatment modalities, and short‐ and long‐term outcomes. Animals: Ten cats diagnosed with ureteral strictures based on compatible findings from at least 2 of the following: ultrasonography, ureteropyelography, surgical exploration, or histopathology. Methods: Retrospective study. Results: Median age, serum creatinine concentration, and size of the renal pelvis were 12 years, 3.7 mg/dL, and 11.75 mm, respectively. Six of 10 cats had hyperechoic periureteral tissue on ultrasound examination at the stricture site. Four cats had evidence of a circumcaval ureter at surgery. Eight cats had an intervention including ureteral stent placement (n = 6) and traditional surgery (n = 2). Seven of 8 cats had decreases in serum creatinine concentration and renal pelvic parameters preceding discharge and 6 had persistently improved results at their last examination. All patients survived to discharge. Median survival time was >294 days (range, 14 to >858 days) with 6/10 cats still alive. Conclusions and Clinical Importance: Ureteral strictures may occur in cats secondary to ureteral surgery, inflammation, a circumcaval ureter, impacted ureterolithiasis, or for unknown causes. With appropriate and timely intervention, the prognosis for long‐term survival is good. In addition to ureteral reimplantation or ureteronephrectomy, ureteral stenting or SC ureteral bypass may be considered as future therapeutic options.  相似文献   
5.
The potential use of RFLP molecular markers for the identification of four creeping bentgrass (Agrostis stolonifera L.) cultivars and one variety of A. tenuis Sibth. used as control, was investigated. Seven probes out of the total 44 screened were able to differentiate all five cultivars at once. On the basis of their genetic similarity the varieties bred at the Pennsylvania State University were grouped closely together, whereas the variety Prominent and the A. tenuis control were more distantly related.  相似文献   
6.
BACKGROUND: There is limited published information regarding feline multiple myeloma. Diagnostic criteria are derived from canine studies and to our knowledge, have not been critically reviewed for cats. OBJECTIVE: To evaluate the clinical and laboratory findings in cats with multiple myeloma and appraise diagnostic criteria. METHODS: Retrospective evaluation of medical records was performed. Inclusion required an antemortem diagnosis of multiple myeloma using 2 of 4 criteria: 1) >or=20% plasma cells in the bone marrow, or >or=10% if atypical plasma cells; 2) paraproteinemia; 3) radiographically-evident osteolysis; 4) light chain proteinuria. Alternatively, a postmortem diagnosis was based on the findings of multiple plasma cell neoplasms, with marrow involvement. RESULTS: Sixteen cats were diagnosed with multiple myeloma between 1996 and 2004, with a median age of 14.0 years; 9 of 16 (56%) were castrated males, and 7 of 16 (44%) were spayed females. Laboratory abnormalities included hyperglobulinemia (14/16, 87.5%), with 11/14 (78.5%) monoclonal and 3/14 (21.4%) biclonal gammopathies; hypoalbuminemia (4/16, 25%); light chain proteinuria, (4/9, 44.4%); hypocholesterolemia (11/16, 68.7%); hypercalcemia, (3/15, 20%); nonregenerative anemia, (11/16, 68.7%); regenerative anemia, (1/16, 6.2%); neutropenia (5/15, 33.3%); thrombocytopenia (8/16, 50%); and marrow plasmacytosis (14/15, 93.3%). Plasma cells were markedly immature, atypical, or both in 10 of 12 (83.3%) cats. Focal or multifocal osteolysis was noted in 6 of 12 (50%) cats for which radiographs were available for review; generalized osteopenia was found in 1 (8.3%) cat. Noncutaneous, extramedullary tumors were found in all cats assessed, 7/7 (100%), including spleen (6), liver (3), and lymph nodes (4). The disease in 1 of 2 cats with cutaneous tumors progressed to plasmacytic leukemia. CONCLUSIONS: Common findings in feline multiple myeloma include atypical plasma cell morphology, hypocholesterolemia, anemia, bone lesions, and multi-organ involvement. Based on the results of this study, we advocate modifying diagnostic criteria in cats to include consideration of plasma cell morphology and visceral organ infiltration.  相似文献   
7.
Cotton and snap bean were selected for a multi-year, multi-state regional (south-eastern USA) research project to evaluate the efficacy of both commercial and experimental bacterial and fungal biological control agents for the management of damping-off diseases. The goal for this portion of the project was to determine the viability and stability of biological agents after application to seed. The biological seed treatments used included: (1) Bacillaceae bacteria, (2) non-Bacillaceae bacteria, (3) the fungus Trichoderma and (4) the fungus Beauveria bassiana. Seed assays were conducted to evaluate the following application factors: short-term (< or = 3 months) stability after seed treatment; quality (i.e. isolate purity); compatibility with chemical pesticides and other biocontrol agents; application uniformity between years and plant species. For the bacterial treatments, the Bacillaceae genera (Bacillus and Paenibacillus) maintained the greatest population of bacteria per seed, the best viability over time and the best application uniformity across years and seed type. The non-Bacillaceae genera Burkholderia and Pseudomonas had the least viability and uniformity. Although Beauveria bassiana was only evaluated one year, the seed fungal populations were high and uniform. The seed fungal populations and uniformity for the Trichoderma isolates were more variable, except for the commercial product T-22. However, this product was contaminated with a Streptomyces isolate in both the years that it was evaluated. The study demonstrated that Bacillaceae can be mixed with Trichoderma isolates or with numerous pesticides to provide an integrated pest control/growth enhancement package.  相似文献   
8.
We derived a formula for estimating the relationship between stem carbon weight and stem volume, which was calculated from DBH and tree height using a combination of stem analysis and soft X-ray densitometry. The results indicate carbon weight in a 33-year-old coastal Japanese black pine (Pinus thunbergii) forest is approximately 68,186 kg ha?1 in Yamagata Prefecture and 38,253 kg ha?1in a 42-year-old black pine forest in Hokkaido Prefecture, Japan. Also, age-related changes in the stem density following oven-drying of samples of black pine trees are small: the oven-dried density (hereafter “density”) of black pine trees in the two locations mentioned above were 425.6 (kg m?3) and 523.2 (kg m?3) respectively, which is comparable to the density (converted from basic density) of black pine of Land Use, Land-Use Change and Forestry (LULUCF) (533 kg m?3). When compared with the carbon weight by the oven-dried density of LULUCF, the carbon weights calculated from each density were 27 % lower in Yamagata and 6 % lower in Hokkaido. This difference directly affects carbon weight for large-scale estimation and thus can create an error at a regional scale. This methodology can contribute to the management of forests acting as carbon sinks.  相似文献   
9.
Isoflavones are the most common phytoestrogens found in human diets. However, it is still not clear whether isoflavones have effects on the reproductive and the endocrine systems under normal dietary intake and overdose. The aim of this study was to determine how the most important isoflavones, genistein and daidzein, affect androgen and glucorticoid levels on male prepuberal rats. A hundred and seventy‐five 30‐day‐old male Wistar rats were dosed orally by stomach tube every day for 35 days, with saline solution, low and high doses of genistein, daidzein and a mixture of both. Serum samples were analysed by an enzyme immunoassay for hormone determinations. In control group, there was a peak of testosterone (T) and dihydrotestosterone levels associated to the onset of puberty, at the third week. However, in low‐dose groups, the same peak was found at the fourth week (p < 0.05), indicating a delay in the onset of puberty in these groups. Moreover, high doses groups serum androgen levels were significantly lower (p < 0.05) than the control group from the first week until fifth week. This fact was supported by a epididymal histological analysis that indicate in low doses there were several content of spermatozoa at fourth week and in high doses there were few content of spermatozoa. Besides, corticosterone levels followed the same pattern of androgens in all groups. We can conclude that oral administration of isoflavones in male rats decreased the secretion of androgens and glucocorticoids causing a delay in the onset of puberty and may cause physiological and developmental problems.  相似文献   
10.
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