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871.
872.
Medical education in mainland China has undergone massive expansion and reforms in the past decades. A nation-wide survey of the five-year clinical medicine programs aimed to examine the course hours, pedagogies, learning resources and teaching staff of anatomy both at present and over the past three decades (1990–1999, 2000–2009, and 2010–2018). The directors or senior teachers from 90 out of the 130 five-year clinical medicine programs were invited to fill out a factual questionnaire by email. Ultimately, sixty-five completed questionnaires were received from 65 different schools. It was found that the total number of gross anatomy course hours has decreased by 11% in the past 30 years and that systematic and regional anatomy have been increasingly taught separately among the surveyed medical schools. Problem-based learning has been adopted in thirty-five (54%) of the surveyed schools, and team-based learning is used in ten (15%) of the surveyed schools. The surveyed schools reported receiving more donated cadavers in recent years, with the average number increasing from 20.67 ± 20.29 in 2000–2009 to 36.10 ± 47.26 in 2010–2018. However, this has not resulted in a decrease in the number of students who needed to share one cadaver (11.85 ± 5.03 in 1990–1999 to 14.22 ± 5.0 in 2010–2018). A decreasing trend regarding the teacher-student ratio (1:25.5 in 2000–2009 to 1:33.2 in 2010–2018) was also reported. The survey demonstrated the historical changes in gross anatomy education in China over the past thirty years. 相似文献
873.
874.
利用组织透明法、石蜡切片法及薄切片法对木兰科10属82种1亚种植物叶片的结构和油细胞的
分布密度、结构及其在叶肉中的分布进行了比较研究。鹅掌楸亚科和木兰亚科在叶结构上的主要区别是:鹅掌楸亚科两种植物叶的部分下表皮细胞乳突状,且整个细胞外壁只形成一个乳突,而在木兰亚科植物中有单列多细胞或单细胞的表皮毛,却未发现乳突;鹅掌楸亚科植物叶主脉维管组织环分隔呈束状,且其外包被的纤维也排列成束状,而木兰亚科的80种1亚种植物中,叶主脉维管组织连成轮状,其外面也由一圈连续的纤维环所包围。从而支持木兰科中木兰亚科和鹅掌楸亚科两个亚科的划分。并且,从叶主脉的演化趋势来看,鹅掌楸亚科较木兰亚科进化。另外,木莲属植物叶片的结构与木兰属具有明显差异,因而进一步证明木莲属是不同于木兰属的一个独立的属。油细胞是木兰科植物叶片解剖的显著特征,在叶肉中的分布可划分为3种类型:(A)主要分布于栅栏组织;(B)主要分布于海绵组织;(c)均匀散布于整个叶肉中。油细胞的大小及其在叶中的分布与叶厚、栅栏组织层数、栅栏组织与海绵组织厚度间的比值以及下皮层的有无、表皮毛的类型、叶脉的结构等特征相结合,可作为属、甚至种的鉴别特征。 相似文献
875.
Ramya Chandrasekaran Shairah Radzi Peh Zhen Kai Preman Rajalingam Jerome Rotgans Sreenivasulu Reddy Mogali 《Anatomical sciences education》2022,15(5):850-862
Due to the modernization of the medical curriculum and technological advancements, anatomy education has evolved beyond cadaveric dissection alone. Plastination techniques, three-dimensional (3D) modeling, and 3D printing technologies have progressively gained importance. However, there are limited valid and reliable surveys to evaluate students' perceptions of these new anatomy tools. Hence, this study aimed to develop a validated instrument to measure students' learning satisfaction, self-efficacy, humanistic values, and perceived limitations of plastinated and 3D printed models. A 41-item survey (five-point Likert scale, 1 = strongly disagree to 5 = strongly agree) was administered to Year 1 undergraduate medical students following a randomized controlled crossover study that evaluated plastinated and 3D printed cardiac and neck models. Ninety-six responses were received, and a factor analysis was performed with the Kaiser–Meyer–Olkin sampling adequacy of 0.878. The confirmatory factor analysis yielded a 4-factor, 19 items model that had a good fit with the latent constructs of 2 (147) = 211.568, P < 0.001, root mean square error of approximation = 0.068, root mean square residual = 0.064, comparative fit index = 0.946, and Tucker Lewis index = 0.937. The Cronbach's alpha for the individual factors ranged from 0.74 to 0.95, indicating good internal consistency. This demonstrated a psychometrically valid and reliable instrument to measure students' perceptions toward plastinated and 3D printed models. 相似文献