全文获取类型
收费全文 | 746篇 |
免费 | 43篇 |
国内免费 | 2篇 |
出版年
2024年 | 1篇 |
2023年 | 6篇 |
2022年 | 14篇 |
2021年 | 37篇 |
2020年 | 24篇 |
2019年 | 22篇 |
2018年 | 23篇 |
2017年 | 30篇 |
2016年 | 40篇 |
2015年 | 49篇 |
2014年 | 70篇 |
2013年 | 65篇 |
2012年 | 73篇 |
2011年 | 56篇 |
2010年 | 48篇 |
2009年 | 30篇 |
2008年 | 21篇 |
2007年 | 43篇 |
2006年 | 32篇 |
2005年 | 26篇 |
2004年 | 19篇 |
2003年 | 22篇 |
2002年 | 10篇 |
2001年 | 5篇 |
2000年 | 2篇 |
1999年 | 4篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 2篇 |
1988年 | 1篇 |
1986年 | 2篇 |
1984年 | 3篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1974年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有791条查询结果,搜索用时 390 毫秒
111.
Flavia E. Saravia Susana L. Gonzalez Paulina Roig Veronique Alves Francoise Homo-Delarche Alejandro F. De Nicola 《Cellular and molecular neurobiology》2001,21(1):15-27
1. Synthesis of oxytocin (OT) and arginine-vasopressin(AVP) is increased in induced models of Type I diabetes, such as thestreptozotocin model. However, these parameters have not yet been evaluated inspontaneous models, such as the nonobese diabetic mouse (NOD). Therefore, we studied in the magnocellular cells of the paraventricular nucleus (PVN)of nondiabetic and diabetic 16-week-old female NOD mice and control C57Bl/6mice, the immunocytochemistry of OT and AVP peptides and their mRNA expression, using nonisotopic in situ hybridization (ISH).2. In nondiabetic and diabetic NOD female mice, the number of OT- and AVP-immunoreactive cells were similar to those of the controls, whereas immunoreaction intensity was significantly higher for both peptides in diabetic NOD as compared with nondiabetic NOD and control C57Bl/6 mice.3. ISH analysis showed that the number of OT mRNA-containing cells was in the same range in the three groups, whereas higher number of AVP mRNA expressing cells was found in diabetic NOD mice. However, the intensity of hybridization signal was also higher for both OT and AVP mRNA in the diabetic group as compared with nondiabetic NOD and control mice.4. Blood chemistry demonstrated that haematrocrit, total plasma proteins, urea, sodium, and potassium were within normal limits in diabetic mice. Thus, NODmice were neither hypernatremic nor dehydrated.5. We suggest that upregulation of OT and AVP reflects a high-stress condition in the NOD mice. Diabetes may affect neuropeptide-producing cells of the PVN, with the increased AVP and OT playing a deleterious role on the outcome of the disease. 相似文献
112.
Juszczyk Paulina Łankiewicz Leszek Kołodziejczyk Aleksandra S. 《International journal of peptide research and therapeutics》2002,9(4-5):187-192
Summary A convenient route to amino acid-based orthogonally protected 1,2-diamines starting from materials readily available for a
peptide chemist is presented. The key step of the procedure is the Mitsunobu reaction ofN-protected aminoalcohol, obtained by the reduction of commercially available Z- or Boc-protected amino acid, with imidodicarbonate
or sulfonylcarbamate related to standard amino-protecting groups used in peptide chemistry yielding triprotected vicinal diamines. 相似文献
113.
114.
115.
116.
We show that, in 1862, Richard Burton collected the type specimen of Pan troglodytes vellerosus not on Mount Cameroon, as has been generally assumed, but in Gabon. Therefore, P. t. vellerosus is not the correct name for the chimpanzee population of western Cameroon and southern Nigeria, if that population is taxonomically
distinct. As First Reviser, we choose the name Pan troglodytes ellioti for this population of chimpanzees, based on Anthropopithecus
ellioti named by Matschie [Matschie P (1914) Neue Affen aus Mittelafrika. Sitzungsber Ges Naturforsch Freunde Berlin 1914:323–342] from a specimen in the Humboldt Museum,
Berlin, collected in Bascho (=Basho), Cameroon, and given to the museum in 1905. 相似文献
117.
118.
Hepatoprotective,Hypoglycemic, and Hypolipidemic Effect of Chokeberry Pomace on Polish Merino Lambs*
To properly understand the biological effect of polyphenol compounds, it should not be assumed that they are generally bioavailable and are reaching tissues as expected. It is important to fully understand how polyphenol compounds are absorbed, metabolized, and finally eliminated from the organism. Most polyphenol compounds occur in the forms that cannot be absorbed in their primary form. Sheep make compounds bioavailable due to their unique digestive system properties. Despite this, several species of ruminants likely to serve as an experimental model were considered. However, due to the high costs for cattle and low popularity in the region of goats, sheep were selected as the experimental model. In the study, 24 Polish Merino lambs were randomly divided into a control and two experimental groups. The experimental groups were administered diets with the addition of 150 or 300?g of chokeberry pomace per each kg of complete feed mixture. Phenolics present in the chokeberry pomace were found to modulate biochemical blood parameters, resulting in hypoglycemic and hypolipidemic effects. Finally, the increase in total phenolics in the serum and liver of lambs induced a health-promoting effect on liver metabolic profile parameters. 相似文献
119.
Suzanne T. E. Lommen Caspar A. Hallmann Eelke Jongejans Bruno Chauvel Melinda Leitsch-Vitalos Alla Aleksanyan Peter Tóth Cristina Preda Maja Šćepanović Huseyin Onen Barbara Tokarska-Guzik Paulina Anastasiu Zita Dorner Annamária Fenesi Gerhard Karrer Katalin Nagy Gyula Pinke Viktor Tiborcz Gergely Zagyvai Mihály Zalai Gabriella Kazinczi Robert Leskovšek Danijela Stešević Guillaume Fried Levani Kalatozishvili Andreas Lemke Heinz Müller-Schärer 《Biological invasions》2018,20(6):1475-1491
To better manage invasive populations, it is vital to understand the environmental drivers underlying spatial variation in demographic performance of invasive individuals and populations. The invasive common ragweed, Ambrosia artemisiifolia, has severe adverse effects on agriculture and human health, due to its vast production of seeds and allergenic pollen. Here, we identify the scale and nature of environmental factors driving individual performance of A. artemisiifolia, and assess their relative importance. We studied 39 populations across the European continent, covering different climatic and habitat conditions. We found that plant size is the most important determinant in variation of per-capita seed and pollen production. Using plant volume as a measure of individual performance, we found that the local environment (i.e. the site) is far more influential for plant volume (explaining 25% of all spatial variation) than geographic position (regional level; 8%) or the neighbouring vegetation (at the plot level; 4%). An overall model including environmental factors at all scales performed better (27%), including the weather (bigger plants in warm and wet conditions), soil type (smaller plants on soils with more sand), and highlighting the negative effects of altitude, neighbouring vegetation and bare soil. Pollen and seed densities varied more than 200-fold between sites, with highest estimates in Croatia, Romania and Hungary. Pollen densities were highest on arable fields, while highest seed densities were found along infrastructure, both significantly higher than on ruderal sites. We discuss implications of these findings for the spatial scale of management interventions against A. artemisiifolia. 相似文献
120.
Adamus-Białek Wioletta Baraniak Anna Wawszczak Monika Głuszek Stanisław Gad Beata Wróbel Klaudia Bator Paulina Majchrzak Marta Parniewski Paweł 《Molecular biology reports》2018,45(5):1055-1065
Molecular Biology Reports - The spreading mechanisms of antibiotic resistance are related to many bacterial and environment factors. The overuse of antibiotics is leading to an unceasing emergence... 相似文献