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61.
M. S. Cunha F. A. F. Soares W. R. Clarindo L. A. O. Campos D. M. Lopes 《Insect molecular biology》2021,30(4):379-389
Genome changes, evidenced through karyotype or nuclear genome size data, can result in reproductive isolation, diversification and speciation. The aim of this study was to understand how changes in the karyotype such as chromosome number and nuclear genome size accompanied the evolution of neotropical stingless bees, and to discuss these data in a phylogenetic context focusing on the karyotype evolution of this clade. We sampled 38 species representing the three Neotropical Meliponini groups; 35 for karyotype analyses and 16 for 1C value measurement. The chromosome number varied from 2n = 16 to 2n = 34, with distinct karyotypic formulae and the presence of a few polymorphisms, such as B chromosomes in one species and arm size differences between homologous chromosomes in two species. The mean 1C value varied from 0.31 pg to 0.92 pg. We associated empirical data on chromosome number and mean 1C value to highlight the importance of Robertsonian fusion rearrangements, leading to a decrease in chromosome number during the Neotropical Meliponini evolution. These data also allowed us to infer the independent heterochromatin amplification in several genera. Although less frequent, Melipona species with 2n = 22 represent evidence of Robertsonian fissions. We also pointed out the importance of chromosomal rearrangements that did not alter chromosome number, such as inversions and heterochromatin amplification. 相似文献
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近年来,世界各国对天然药物日益重视,而中药配方颗粒既能在中医理论指导下随证加减,又有服用便捷、适宜工业生产等优点,成为推动中药"走出去"的有力助力。通过回顾中药配方颗粒的发展历程、分析相关数据和国内外发展形势,对中药配方颗粒的研究现状、市场情况及国际化发展面临的主要挑战进行探讨,提出利用政府间交往推进中药国际贸易、充分发挥海外资源平台作用、帮助监管部门建立符合中药配方颗粒特点和审批国政策的合理化国际审批方案、争取国际标准主导权的建议,为推动中药配方颗粒产业在世界范围内高质量发展提供参考。 相似文献
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What can be learned from historical anatomical drawings and how to incorporate these drawings into anatomical teaching? The drawing “A skull sectioned” (RL 19058v) by Leonardo da Vinci (1452–1519), hides more detailed information than reported earlier. A well‐chosen section cut explores sectioned paranasal sinuses and ductus nasolacrimalis. A dissected lateral wall of the maxilla is also present. Furthermore, at the level of the foramen mentale, the drawing displays compact and spongious bony components, together with a cross‐section through the foramen mentale and its connection with the canalis mandibulae. Leonardo was the first to describe a correct dental formula (6424) and made efforts to place this formula above the related dental elements. However, taking into account, the morphological features of the individual elements of the maxilla, it can be suggested that Leonardo sketched a “peculiar dental element” on the position of the right maxillary premolar in the dental sketch. The fact that the author did not make any comment on that special element is remarkable. Leonardo could have had sufficient knowledge of the precise morphology of maxillary and mandibular premolars, since the author depicted these elements in the dissected skull. The fact that the author also had access to premolars in situ corroborates our suggestion that “something went wrong” in this part of the drawing. The present study shows that historical anatomical drawings are very useful for interactive learning of detailed anatomy for students in medicine and dentistry. Clin. Anat., 2013. © 2012 Wiley Periodicals, Inc. 相似文献
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国家中医药管理局颁布的《古代经典名方目录(第一批)》中小续命汤出自《备急千金要方》卷八·诸风,该文对小续命汤来源的追溯、历史发展、变化的进程及临床应用均进行系统的考证。考证结果表明,续命汤及其类方是唐宋以前治疗中风的主要方剂,延绵七八百年,为治风准绳,其中以小续命汤最具代表性。小续命汤由续命汤衍变而来,方名最早出现于东晋《小品方》,唐代孙思邈将其纳入《备急千金要方》,对其治疗中风的疗效推崇备至,曰“诸风服之皆验”,后经《外台秘要》及多部医著记载,被列为治疗中风第一要方。宋以后,随着医家对中风病机认识的变化及对小续命汤认识的局限性导致其在中风证的临床应用中逐渐减少,近现代以来又被重新认知和应用,期间其临床应用也发生了较大的变迁。其临床应用范围广泛,涉及多种脑部及神经系统相关疾病,包括但不限于①脑卒中及其后遗症,②周围性面瘫,③类风湿关节炎,④高血压,⑤其他运动神经系统疾病等。主治为脑卒中及其后遗症,其次为周围性面瘫,还有其他新的适应证正逐渐被发现,以上为小续命汤的临床定位、新药转化研究提供有效性安全性的参考依据。 相似文献
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Starting enteral nutrition with preterm single donor milk instead of formula affects time to full enteral feeding in very low birthweight infants 下载免费PDF全文
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Mathematical formulae are commonly used to estimate intra-cranial haematoma volume. Such formulae tacitly assume an ellipsoid geometrical morphology. Recently, the ‘XYZ/2’ formula has been validated and recommended for chronic subdural haematoma (CSDH) volumetric estimation. We aimed to assess the precision and accuracy of mathematical formulae specifically in estimating CSDH volume, and to determine typical CSDH 3-D morphology. Three extant formulae (‘XYZ/2’, ‘π/6·XYZ’ and ‘2/3S·h’) were compared against computer-assisted 3D volumetric analysis as Gold standard in CTs where CSDH sufficiently contrasted with brain. Scatter-plots (n = 45) indicated that, in contrast to prior reports, all formulae most commonly over-estimated CSDH volume against 3-D Gold standard (‘2/3S·h’: 44.4%, ‘XYZ/2’: 48.84% and ‘π/6·XYZ’: 55.6%). With all formulae, imprecision increased with increased CSDH volume: in particular, with clinically-relevant CSDH volumes (i.e. >50 ml). Deviations >10% of equivalence were observed in 60% of estimates for 2/3S·h, 77.8% for ‘XYZ/2’ and 84.4% for ‘π/6·XYZ’. The maximum error for ‘XYZ/2’ was 142.3% of a clinically-relevant volume. Three-D simulations revealed that only 4/45 (9%) CSDH remotely conformed to ellipsoid geometrical morphology. Most (41/45, 91%) demonstrated highly irregular morphology neither recognisable as ellipsoid, nor as any other regular/non-regular geometric solid. Conclusions: Mathematical formulae, including ‘XYZ/2’, most commonly proved inaccurate and imprecise when applied to CSDH. In contrast to prior studies, all most commonly over-estimated CSDH volume. Imprecision increased with CSDH volume, and was maximal with clinically-relevant CSDH volumes. Errors most commonly related to a flawed assumption regarding ellipsoid 3-D CSDH morphology. The validity of mean comparisons, or correlation analyses, used in prior studies is questioned. 相似文献
70.
Yun-Xiao Zhou Yun-Qing Qiu Li-Qian Xu Jing Guo Lan-Juan Li 《African journal of traditional, complementary, and alternative medicines》2012,9(3):405-411
This study explored the effects of a classical Chinese medicine formula- Xiao-Chai-Hu Tang(XCHT) on the model mice with D-galactosamine -induced liver injury. Sixty male imprinting control region (ICR) mice were used in the present study, and they were separated randomly into 6 groups: a normal control group (Group A, n=10), a model control (Group B, n=10), a positive control (Group C, n=10), a low dose of XCHT group (Group D, n=10), a medium dose of XCHT group (Group E, n=10), and a high dose of XCHT group (Group F, n=10). ELISA was used to detect the IL-6 and TNF-α levels in the serum. Real-time PCR was performed to assess the expression of FasmRNA, Fas-LmRNA, Bcl-2mRNA of the liver tissues. Western blotting was used to detect the Bax protein expression of the liver tissues. The serum IL-6 and TNF-α levels of Group B were significantly higher than the other groups (P<0.05). The expression of Fas mRNA, Fas-LmRNA, and Bax protein of the liver tissues of Group B were significantly higher than those of the other groups (P<0.05). The expression of Bcl-2 mRNA of the liver tissues of Group B was significantly lower than other groups (P<0.05). Both of XCHT and biphenyl dicarboxylate significantly decreased the serum IL-6 and TNF-α levels and FasmRNA, FasLmRNA, Bax protein expression and increased the Bcl-2 mRNA expression of the liver tissues of model mice (P<0.05). It may be through decreasing the serum IL-6 and TNF-α levels and FasmRNA, FasLmRNA, Bax protein expression and increasing the Bcl-2 mRNA expression of the liver tissues that XCHT significantly relieved the D-galactosamine -induced liver injury. 相似文献