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311.
Kohya Uematsu Tomoyuki Kawase Masaki Nagata Kenji Suzuki Kazuhiro Okuda Hiromasa Yoshie Douglas M. Burns Ritsuo Takagi 《Stem cell research》2013,10(1):1-19
We have previously demonstrated that multilayered periosteal sheets prepared from the explant culture of alveolar periosteum serve as a promising osteogenic grafting material in periodontal tissue regeneration. For the preparation of more potent periosteal sheets, we examined the applicability of stem-cell culture media. Compared to the control medium (Medium 199 + 10% FBS), periosteal sheets expanded with MesenPRO-RS? medium exhibited these features: Cells grew three-dimensionally and deposited collagen in the extracellular spaces to form thicker multilayers of cells. Chondrocytic markers were not significantly upregulated. Contractile force was generated in proportion with the increased thickness of the periosteal sheets and the formation of cytoplasmic α-smooth muscle actin fibers. However, myofibroblastic markers were not significantly upregulated. The surface marker CD146 was substantially upregulated, while both CD73 and CD105 were downregulated. Alkaline phosphatase, a representative osteoblastic marker, was not upregulated by osteogenic induction. However, these expanded periosteal sheets exhibited substantially stronger osteogenic differentiation when implanted in nude mice. Therefore, despite our reservations, MesenPRO medium effectively expanded the cells contained in periosteal sheets to promote the formation of thicker multilayers of cells in vitro, and these enhanced periosteal sheets expressed increased osteogenic potential at implantation sites in vivo. In conjunction with data indicating that CD146-positive cells were notably expanded and the recently proposed concept that CD146 is a marker for osteogenic progenitor cells found in the bone marrow stroma, our findings suggest that MesenPRO medium improves the preparation of highly osteogenic periosteal sheets suitable for clinical application largely through the induction of CD146-positive cells. 相似文献
312.
N. Yamaguchi K-I. Tokita A. Uematsu K. Kuno M. Saeki E. Hiraoka K. Uchida M. Hotta F. Nakayama M. Takahashi H. Nakamura & H. Higuchi 《Journal of Zoology》2008,276(1):54-62
We describe the detoured migration route of the Oriental honey-buzzard Pernis ptilorhyncus , showing differences between autumn and spring migration, using data from 10 adult individuals marked with satellite transmitters. In autumn, the migration routes were very similar from Japan to the south end of the Malay Peninsula. The wintering sites were distributed within the Philippines, Borneo and the Malay Archipelago. During autumn, migration of the birds had few long-term stopover sites, instead, sometimes decidedly slowing their migration rate while proceeding in a consistent direction. During spring migration, the honey-buzzards penetrated into southern China, moving north to the base of the Korean Peninsula. The birds then went south through the Korean Peninsula to reach Japan. Before travelling to China, all spring migrants stopped for several weeks in south-east Asia. The slow rate of travel in the autumn suggests that migrants were foraging and replenishing their energy reserves. Instead of a migration strategy that uses only a few long-term stopover sites, honey-buzzards may adopt a strategy based on a number of short-term stay sites. 相似文献
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317.
I Kakuta K Namba K Uematsu S Murachi 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1991,100(3):405-411
1. Carp were exposed to 280 ppm formalin. Haematocrit and plasma glucose and lactic acid increased. In moribund fish, blood pH was remarkably lower and plasma protein increased. 2. When exposed to formalin, heart rate (HR) and respiration increased briefly, and then decreased. 3. Some fish increased urine flow (UF) immediately and maintained higher values for a while, followed by gradual decrease, and others decreased UF consistently. UF stopped at 30 min or longer prior to fish death. Urine osmotic pressure was higher at the 1st to 2nd hour and immediately before UF stopped. 4. The relationship between UF, HR and respiration was also discussed. 相似文献
318.
Kazumasa Uematsu 《Ichthyological Research》1986,33(3):293-303
The autonomic innervation of the ovary of the dab was studied histologically and physiologically. The ovary receives a branch of nerve bundles that emerge into the abdominal cavity at the postero-ventral end of the kidney and can be traced back to the sympathetic chain in the vicinity of the 5th vertebra. Almost all the nerve fibers are AChE-positive, and some of them also emit adrenergic fluorescence. Electrical stimulation of the ovarian nerves caused ovarian contractions, and administration of ACh elicited contractions of the ovary preparations, supporting the hypothesis that the ovary is innervated by excitatory cholinergic fibers. In the ovarian nerve bundles, many AChE-positive and non-fluorescent ganglion cells are scattered. Ultrastructural studies suggest that nerve endings situated on the ovarian smooth muscle and on ganglion cells are cholinergic. These results also suggest that the cells are the post-ganglionic neurons of the cholinergic innervation and the axons of the cells reach to the muscle cells. On the other hand, the adrenergic fluoresecent fibers possibly participate in the inhibitory innervation, since the presence of inhibitory beta-adrenoceptors were demonstrated by pharmacological studies. 相似文献
319.
S Uematsu A E Rosenbaum D L Abel Y S Erozan P K Gupta B S Carson A J Kumar 《Applied neurophysiology》1987,50(1-6):114-118
A thermoplastic helmet was designed to allow the use of the Leksell stereotactic frame in infants. 相似文献
320.
Takeshi Osawa Hiromune Mitsuhashi Yuta Uematsu Atushi Ushimaru 《Ecological Informatics》2011,6(5):270-275
Species-occurrence data sets tend to contain a large proportion of zero values, i.e., absence values (zero-inflated). Statistical inference using such data sets is likely to be inefficient or lead to incorrect conclusions unless the data are treated carefully. In this study, we propose a new modeling method to overcome the problems caused by zero-inflated data sets that involves a regression model and a machine-learning technique. We combined a generalized liner model (GLM), which is widely used in ecology, and bootstrap aggregation (bagging), a machine-learning technique. We established distribution models of Vincetoxicum pycnostelma (a vascular plant) and Ninox scutulata (an owl), both of which are endangered and have zero-inflated distribution patterns, using our new method and traditional GLM and compared model performances. At the same time we modeled four theoretical data sets that contained different ratios of presence/absence values using new and traditional methods and also compared model performances. For distribution models, our new method showed good performance compared to traditional GLMs. After bagging, area under the curve (AUC) values were almost the same as with traditional methods, but sensitivity values were higher. Additionally, our new method showed high sensitivity values compared to the traditional GLM when modeling a theoretical data set containing a large proportion of zero values. These results indicate that our new method has high predictive ability with presence data when analyzing zero-inflated data sets. Generally, predicting presence data is more difficult than predicting absence data. Our new modeling method has potential for advancing species distribution modeling. 相似文献