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1.
Transversal, horizontal and sagittal sections of the brain were stained by the ancient but efficient Mulligan method, a procedure that establishes a clear macroscopic difference between the white and grey substances. Different structures of each section were studied and most of the details were identified and named according to the NAV. All sections were projected onto the whole brain. By means of this easy and basic procedure the students increase their understanding of (1) the size and/or the form and/or the topography of several prominent structures of the brain, (2) the general distribution of the substancia alba and grisea, and they begin to understand the complexity of the brain.  相似文献   
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Most mammals have two different structures in which we found glomerular layers at the same time: the main olfactory bulb (MOB) and the accessory olfactory bulb (AOB). Both bulbs have the same pattern of organization, but there are some differences: although the size is considerably bigger in MOB than in AOB, probably the most important difference is that the principal cells are not differentiated into mitral and tufted cells in the AOB, and are usually described as mitral/tufted cells. We have previously observed that in some mammals, like pigs and sheep, the AOB reaches maturity before birth, but this is not a rule for other species. Surprisingly, mice need several days of life to achieve full stratification of its cellular components. We have studied the chronology of this process, focusing our attention on the glomerular layer, the last to appear. We concluded that there are two critical periods, between E11.5 and E16.5 (migration phase) and between E17.5 and P3.5–7 (true morphological constitution).  相似文献   
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The aim of this study was to investigate the variability of the internal pudendal artery. Two hundred and thirty‐two pelvic halves from 116 adult dogs were examined. Twenty‐six anatomical variations were found, thirteen occurring in more than 5% of the dogs. Anatomical variations were grouped in relation to the origin of the prostatic/vaginal arteries, middle rectal artery, urethral artery, ventral perineal and caudal rectal arteries. The chi‐squared test was used to analyse differences in sex, side of the body, profile and size, and the results were considered statistically significant when  0.05. An identical vascular pattern in both hemipelvises was found for most of the anatomical variations described.  相似文献   
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The aim of this study was to analyse and describe the variability of the umbilical artery. Two hundred and thirty‐two pelvic halves from 116 adult dogs were examined. To study the permeability of the umbilical artery, ten adult dogs, nine newborns and thirteen foetuses between 35 and 50 days of gestation were also used. In relation to the origin of the umbilical artery, six anatomical variations were found. From which five involved a cranial (= 4) or caudal (= 1) relocation of its origin, and in one case (= 1), the umbilical artery arose from the median sacral artery. In eight cases, the umbilical artery gave off the prostatic (= 1) or vaginal (= 7) arteries. The permeability of the umbilical artery was the most significant anatomical variation: permeability was detected in 45% (106 of 232 pelvic halves) of all cases, from which 36 were males and 70 females. Interestingly, an equal vascular permeability in both hemipelvises was found for 82% of the dogs, thus additional data related to such feature of the umbilical artery was also recorded. In accordance with the statistical study, the main anatomical variations described showed significant values for gender, side of the body, size and profile variables.  相似文献   
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Surface properties of fibrous and ground cotton and linen were investigated by inverse gas chromatography (IGC) and the contact angle with different liquids was also measured on fabrics composed of both fibers. Results proved that dispersion component of surface tension (γ s d ) determined by IGC depends not only on the surface energy, but also on several factors influencing the adsorbability of probe molecules on the cellulosic substrates. For cotton samples, the trapping of n-alkanes among waxy molecules in the outer layer of fibers can be presumed. This effect results in larger γ s d for cotton fibers than for linen in spite of the higher wettability of the linen fabrics. Besides the surface energy and trapping effects, the grinding also influences the γ s d values. Specific enthalpy of adsorption (ΔH A ab ) of polar probes could be determined on all linen samples, but only on the ground cotton sample. Lewis acid-base character calculated for linen and ground cotton samples depends on the same effects as the γ s d does. The similar ΔH A ab values of chloroform (acidic) and THF (basic) measured on each of the samples support the conclusion that the surface character is amphoteric, which is also proved by the high ΔH A ab values of the amphoteric ethyl acetate and acetone probes.  相似文献   
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MicroRNAs (miRNAs) are a class of small non-coding RNAs with a critical role in development and environmental responses. Efficient and reliable detection of miRNAs is an essential step towards understanding their roles in specific cells and tissues. However, gel-based assays currently used to detect miRNAs are very limited in terms of throughput, sensitivity and specificity. Here we provide protocols for detection and quantification of miRNAs by RT-PCR. We describe an end-point and real-time looped RT-PCR procedure and demonstrate detection of miRNAs from as little as 20 pg of plant tissue total RNA and from total RNA isolated from as little as 0.1 μl of phloem sap. In addition, we have developed an alternative real-time PCR assay that can further improve specificity when detecting low abundant miRNAs. Using this assay, we have demonstrated that miRNAs are differentially expressed in the phloem sap and the surrounding vascular tissue. This method enables fast, sensitive and specific miRNA expression profiling and is suitable for facilitation of high-throughput detection and quantification of miRNA expression.  相似文献   
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