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排序方式: 共有182条查询结果,搜索用时 15 毫秒
131.
This study was part of a multidisciplinary investigation of the effects of gestational ethanol exposure in nonhuman primates. Thirty-one pregnant Macaca nemestrina were exposed to weekly ethanol doses of 0.0, 0.3, 0.6, 1.2, 1.8, 2.5, 3.3, or 4.1 g/kg maternal weight. Dose cohorts 0.0 through 1.8 were exposed to the initial ethanol dose within 10 days postconception. Dose cohorts 2.5 through 4.1 received their initial dose after the fifth week of gestation. Morphometric analyses performed on cranial radiographs showed that animals exposed to high doses of gestational ethanol had, on average, slightly smaller, distorted crania than control animals. A dysmorphic, flat face characteristic of fetal alcohol syndrome was recognized in one animal of the 1.8 g/kg cohort. The animal that received the highest doses of gestational ethanol was microcephalic. Similar malformations were not seen with low ethanol exposures or in controls. These data suggest a pattern of cranial distortion that may be recognizable and characteristic of ethanol teratogenesis. 相似文献
132.
Panomycocin, a novel exo-beta 1,3 glucanase, was tested as an antifungal agent against green and blue mold diseases, the most
important causes of post harvest decay in citrus fruits. All tested isolates of Penicillium digitatum and Penicillium italicum were susceptible to panomycocin in vitro. Effective panomycocin concentrations for 50% growth inhibition (MIC-2) for P. digitatum and P. italicum were 2 and 1 μg ml−1, respectively. Complete (MIC-0) growth inhibition of all isolates observed at a panomycocin concentration of 16 μg ml−1. Treatment of spores with panomycocin at values lower than the MIC-0 led to slower germ tube elongation and mycelium growth.
In tests on fruit, panomycocin at concentrations equal to in vitro MIC-0 value protected lemon fruit from decay. 相似文献
133.
Demet Toprak Ahmet Toprak Wei Chen Ji Hua Xu Sathanur Srinivasan Gerald S. Berenson 《Obesity (Silver Spring, Md.)》2011,19(1):185-190
To determine the association between cardiovascular (CV) risk factors in childhood and high‐sensitivity C‐reactive protein (hsCRP) and adiponectin in adulthood, 835 eligible white and African‐American young adult subjects (age range 24–42 years, average 34 years, 43% men, 31% African Americans) who had CV risk‐factor variable data from their childhood (20 years earlier, age range 5–18 years, average 14 years) were selected. Stepwise linear regression models revealed that mean logarithmic hsCRP level in adulthood was 0.02 greater with every increase of 1 mm in skinfold thickness in childhood, 0.25 greater for African Americans than whites, 0.36 greater for girls than boys, and 0.15 greater for every unit increase in BMI z score. Mean logarithmic adiponectin level in adulthood was 0.36 greater for girls than boys, 0.22 greater for whites than African Americans, and 0.01 less with every increase of 1 mm of childhood skinfold thickness. Seventy participants (8%) were overweight or obese in their childhood, and 64 of these (91%) remained obese in their young adulthood. In conclusion, childhood adiposity and African‐American race were associated with higher hsCRP and lower adiponectin levels in their adulthood. Skinfold thickness and BMI z score in childhood were the main obesity determinants for higher hsCRP and lower adiponectin levels in young adulthood. 相似文献
134.
Kurt Hulyam Bayramoglu Aysegul Gunes Hasan Veysi Ozbabalik Demet Degirmenci Irfan Colak Ertugrul Cosan Turgut Didem Bayram Banu Dikmen Miris 《Journal of cellular and molecular medicine》2013,17(4):475-481
This study was performed in acute stroke patients in the Turkish population to determine the frequency of the A1166C polymorphism in the AT1 gene and to examine the role of this polymorphism in acute stroke development. In this study, 257 genomic DNA samples were analysed (from 206 acute stroke patients and 51 healthy individuals). Genomic DNA was prepared from peripheral blood using the salt‐extraction method. The presence of the A1166C polymorphism in the AT1 gene was determined using the polymerase chain reaction (PCR)‐restriction fragment length polymorphism (RFLP) method. PCR products were separated by 2% agarose gel electrophoresis and visualized by a charge‐coupled device (CCD) camera. In this study, the allele frequency at the A1166C position was 92% A and 8% C for control and 97% A and 3% C for patients. This difference in allele frequency between the control group and the patient group was not statistically significant. However, genotype and allele frequencies showed a significant difference (P < 0.001) in the control and the patient groups. The results of this study show no relationship between the A1166C polymorphism in the AT1 gene and acute stroke in the Turkish population. 相似文献
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137.
Andrea Santangeli Tuuli Toivonen Federico Montesino Pouzols Mark Pogson Astley Hastings Pete Smith Atte Moilanen 《Global Change Biology Bioenergy》2016,8(5):941-951
Reliance on fossil fuels is causing unprecedented climate change and is accelerating environmental degradation and global biodiversity loss. Together, climate change and biodiversity loss, if not averted urgently, may inflict severe damage on ecosystem processes, functions and services that support the welfare of modern societies. Increasing renewable energy deployment and expanding the current protected area network represent key solutions to these challenges, but conflicts may arise over the use of limited land for energy production as opposed to biodiversity conservation. Here, we compare recently identified core areas for the expansion of the global protected area network with the renewable energy potential available from land‐based solar photovoltaic, wind energy and bioenergy (in the form of Miscanthus × giganteus). We show that these energy sources have very different biodiversity impacts and net energy contributions. The extent of risks and opportunities deriving from renewable energy development is highly dependent on the type of renewable source harvested, the restrictions imposed on energy harvest and the region considered, with Central America appearing at particularly high potential risk from renewable energy expansion. Without restrictions on power generation due to factors such as production and transport costs, we show that bioenergy production is a major potential threat to biodiversity, while the potential impact of wind and solar appears smaller than that of bioenergy. However, these differences become reduced when energy potential is restricted by external factors including local energy demand. Overall, we found that areas of opportunity for developing solar and wind energy with little harm to biodiversity could exist in several regions of the world, with the magnitude of potential impact being particularly dependent on restrictions imposed by local energy demand. The evidence provided here helps guide sustainable development of renewable energy and contributes to the targeting of global efforts in climate mitigation and biodiversity conservation. 相似文献
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139.
The function of synaptotagmin as a Ca2+ sensor in neurotransmitter release involves Ca2+-dependent phospholipid binding to its two C2 domains, but this activity alone does not explain why Ca2+ binding to the C2B domain is more critical for release than Ca2+ binding to the C2A domain. Synaptotagmin also binds to SNARE complexes, which are central components of the membrane fusion machinery, and displaces complexins from the SNAREs. However, it is unclear how phospholipid binding to synaptotagmin is coupled to SNARE binding and complexin displacement. Using supported lipid bilayers deposited within microfluidic channels, we now show that Ca2+ induces simultaneous binding of synaptotagmin to phospholipid membranes and SNARE complexes, resulting in an intimate quaternary complex that we name SSCAP complex. Mutagenesis experiments show that Ca2+ binding to the C2B domain is critical for SSCAP complex formation and displacement of complexin, providing a clear rationale for the preponderant role of the C2B domain in release. This and other correlations between the effects of mutations on SSCAP complex formation and their functional effects in vivo suggest a key role for this complex in release. We propose a model whereby the highly positive electrostatic potential at the tip of the SSCAP complex helps to induce membrane fusion during release. 相似文献
140.
Gerda Bernhard Ronald A. Knibbe Alessa von Wolff Demet Dingoyan Holger Schulz Mike M?sko 《PloS one》2015,10(12)