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For determination of the oestrous cycle in rats classical Papanicolaou technique has long been used successfully. Instead of using many stains in Papanicolaou, staining the vaginal secretions with only methylene blue has also been defined. Recently a new technique in which vaginal samples are directly examined under light microscope has been introduced. The aim of this study was to assess the reliability of this new technique by comparing it with the classical staining techniques. From 20 Wistar rats 60 vaginal samples were collected with a micropipette, three from each. Briefly, the vagina was flushed two to three times then the fluid was placed onto a glass slide. The fluid was equally distributed onto three glass slides. The glass slides were coded. Two samples were stained with Papanicolaou and methylene blue while the other one was examined directly. Determination of the phases of the oestrous cycle was made by the same histologist who was blinded to the groups and coding system. After determination of the oestrous phase in all samples, the results were compared and it was found that the results were matching. In conclusion, the same results can be obtained with the direct examination technique and this technique is reliable, so there is no need to use relatively time-consuming, less practical and more expensive techniques such as Papanicolaou or methylene blue.  相似文献   
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E. Tunc    D. Erdogan    R. Gozil    M. Bahcelioglu    E. Calguner    G. Take    G. Caglar    H. Oktem 《Anatomia, histologia, embryologia》2009,38(2):128-132
Methylphenidate hydrochloride (MPH), more commonly known as Ritalin, is a piperidine derivative and is the drug most often used to treat attention deficit/hyperactivity disorder, one of the most common behavioural disorders of children and young adults. The aim of this study was to investigate dose-dependent immunohistochemical Dopamine 2 receptor (D2) expression and apoptosis in the rat cornea and cornea. In this study, 27 female pre-pubertal Wistar albino rats, divided into three different dose groups (5, 10 and 20 mg/kg) and their control groups, were used. They were treated orally with methylphenidate dissolved in saline solution for 5 days per week during 3 months. At the end of the third month, after perfusion fixation, eye tissue was removed. Paraffin sections were collected for immunohistochemical and terminal deoxynucleotidyl-transferase-mediated dUTP-biotin nick end labelling assay studies. In our study, we observed that the cornea D2 receptor reactivity showed a dose-related increase after MPH treatment, especially in basal cells of the epithelium and a dose-dependent decrease in the retinal ganglion cell which was statistically meaningful. Analysis of the cornea thickness results showed no meaningful difference between groups. Apoptotic cell number showed a meaningful increase in the high dose treated group compared to the other groups of the study. The data suggest that Ritalin has degenerative effect on the important functional part of the eye, such as cornea and retina and its activating dopaminergic mechanism via similar neuronal paths, functionally and structurally, to induce morphological changes. As a result, we believe that this morphological changes negatively effecting functional organization of the affected cornea and retina.  相似文献   
4.
An automated wood texture recognition system of 48 tropical wood species is presented. For each wood species, 100 macroscopic texture images are captured from different timber logs where 70 images are used for training while 30 images are used for testing. In this work, a fuzzy pre-classifier is used to complement a set of support vector machines (SVM) to manage the large wood database and classify the wood species efficiently. Given a test image, a set of texture pore features is extracted from the image and used as inputs to a fuzzy pre-classifier which assigns it to one of the four broad categories. Then, another set of texture features is extracted from the image and used with the SVM dedicated to the selected category to further classify the test image to a particular wood species. The advantage of dividing the database into four smaller databases is that when a new wood species is added into the system, only the SVM classifier of one of the four databases needs to be retrained instead of those of the entire database. This shortens the training time and emulates the experts’ reasoning when expanding the wood database. The results show that the proposed model is more robust as the size of wood database is increased.  相似文献   
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Shi drum (Umbrina cirrosa L.) is regarded as a promising new candidate for Mediterranean mariculture but specifically formulated feeds are not yet available due to knowledge gaps in its basic nutritional requirements. Therefore, this study was carried out to determine the effects of dietary lipid levels on growth and feed utilization in shi drum (72.6 g average weight). Four isonitrogenic diets differing in dietary lipid levels between 10 and 19% (named 10L, 13L, 16L, and 19L, respectively) were fed to triplicate groups of fish for 8 weeks. Growth was not affected by treatment whereas feed efficiency was significantly deteriorated in fish fed diets containing lipid higher than 13%. Whole body dry matter and lipid contents were significantly higher in fish fed 19L compared with fish fed the 10L, while whole body protein, ash, and total carbon (C) were statistically unaffected by the dietary treatment. A significant increase in feed, lipid, energy, nitrogen (N), and carbon (C) intake was recorded in fish fed 16L and 19L when compared with 10L. Carbon/nitrogen (C/N) ratio was significantly higher in fish fed 19L than 10L. Moreover, the N and C losses significantly increased in fish fed 19L compared with 10L and 13L. It was concluded that high dietary lipid did neither had any protein-sparing effect nor other positive result, and diets for shi drum are not recommended to contain more than 13% lipid.  相似文献   
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A two-year field study was conducted to determine the effects on the growth, yield, heavy metal content, and water use of cauliflowers and on the soil chemical properties of irrigation with reclaimed urban wastewaters (filtered, aerated, diluted) by comparing with fresh water under semi-arid climate conditions. Cauliflower curd yield, water use efficiency, and heavy metal contents were found to be the highest in the filtered wastewater application. Cadmium (Cd) content was just over the critical level for human health. Filtered and aerated wastewater applications created higher soil salinity, organic matter, and total nitrogen (N), dipotassium oxide (K2O), and phosphorus pentoxide (P2O5) contents. Copper (Cu), iron (Fe), and manganese (Mn) contents in the surface soil were also found to be significantly higher. Treated-wastewater irrigation could increase cauliflower yield and water productivity. However, higher heavy metal contaminations under these conditions may increase health risks. Therefore, the diluted wastewater application may be preferred, but it must be utilized while taking human health into account.  相似文献   
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[目的]N2作保护气,用管式热解炉对新疆棉秆进行热解实验研究,确定液相产率最高时的最佳工艺条件.[方法]通过设计L9(34)正交试验及单因素实验,以液相产率为目标函数,分析讨论升温速率、热解温度、恒温时间、粒径对产率的影响.[结果]四个因素的显著性从主到次的顺序为:升温速率>热解温度>恒温时间>粒径,最佳工艺条件为:升温速率27℃/min、热解温度550℃C、恒温时间20 min、粒径10 mm >dp >1mm.[结论]在最佳工艺条件下棉秆热解所得生物质油的得率为49.7;.  相似文献   
8.
Methylphenidate, more commonly known as Ritalin, is a piperidine derivative and is the drug most often used to treat attention deficit/hyperactivity disorder, one of the most common behavioural disorders of children and young adults. Our aims were to investigate dose-dependent immunohistochemical D2 expression and ultrastructural changes of the rat heart tissue, and to demonstrate possible toxicity of the long-term and high dose use of the methylphenidate. In this study, 27 female pre-pubertal Wistar albino rats, divided into three different dose groups (5, 10 and 20 mg/kg) and their control groups, were used. They were treated orally with methylphenidate dissolved in saline solution for 5 days/week during 3 months. At the end of the third month, after perfusion fixation, left ventricle of cardiac tissue was removed. Paraffin, semi-thin and thin sections were collected and immunohistochemical, terminal deoxynucleotidyl transferase-mediated Dig-dUTP nick end labelling assay and ultrastructural studies were performed. In conclusion, we believe that Ritalin is dose-related affecting dopaminergic system to increase heart rhythm and contraction. Thus, this drug may cause degenerative ultrastructural changes in mitochondrial path.  相似文献   
9.
This study was undertaken to determine the dietary protein requirement of shi drum (Umbrina cirrosa L.) with an initial weight of 86.3±0.4 g. The fish were fed five isoenergetic diets containing dietary protein levels ranging from 35% to 59% by 6% increments [the estimated digestible protein (DP) levels ranged between 29.6% and 52.8%], and the growth response over a 10‐week period was monitored. Each experimental diet was given to triplicate groups of fish. The final weight, weight gain and daily growth coefficient increased with the dietary protein level, reaching a plateau at the dietary level of 47% protein. The feed conversion ratio improved with increasing dietary protein level. The daily feed intake was significantly lower in fish fed 53% and 59% protein diets compared with those fed 35% protein diet. However, protein intake showed an increasing trend with increasing dietary protein and became significantly different between the 59% and the 35% protein diets. The protein efficiency ratio, protein retention and condition factor were not affected significantly by the dietary treatments. The final body composition was not influenced by the treatments. The recommended dietary protein percentage and DP/digestible energy (DE) ratio for juvenile shi drum diets are 51.4% (45.6% DP) and 28.5 g DP MJ DE?1 respectively.  相似文献   
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A field study was conducted to determine effects of seasonal deficit irrigation on plant cob, leaf, stem and total fresh yield, plant height and water use efficiency (WUE) of silage maize for a 2-year period in the semiarid region. In addition, the crop and pan coefficients k c and k p of silage maize were determined in full irrigation conditions. Irrigations were applied when approximately 50% of the usable soil moisture was consumed in the effective rooting depth at the full irrigation treatment. In deficit irrigation treatments, irrigations were applied at the rates of 80, 60, 40, 20 and 0% of full irrigation treatment on the same day. Irrigation water was applied by hose-drawn traveler with a line of sprinklers. Increasing water deficits resulted in a relatively lower cob, leaf, stem and total fresh yields. The linear relationship between evapotranspiration and total fresh yield were obtained. Similarly, WUE was the highest in full irrigation conditions and the lowest in continuous stress conditions. According to the averaged values of 2 years, yield response factor (k y) was 1.51 for silage maize. When combined values of 2 years, seasonal pan coefficient (k p) and seasonal crop coefficient (k c) were determined as 0.84 and as 1.01 for silage maize, respectively.  相似文献   
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