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1.
A continuous production of fructooligosaccharides from sucrose was investigated by fructosyltransferase immobilized on a high porous resin, Diaion HPA 25. The optimum pH (5.5) and temperature (55°C) of the enzyme for activity was unaltered by immobilization, and the immobilized enzyme became less sensitive to the pH change. The optimal operation conditions of the immobilized enzyme column for maximizing the productivity were as follows: 600 g/L of sucrose feed concentration, flow rate of superficial space velocity 2.7 h?1. When the enzyme column was run at 50°C, about 8% loss of the initial activity of immobilized enzyme was observed after 30 days of continuous operation, during which high productivity of 1174 g/L·h was achieved. The kinds of products obtained using the immobilized enzyme were almost the same as those using soluble enzymes or free cells. 相似文献
2.
Kyung Ah Koo Randal L. Walker Emily S. Davenport Charles S. Hopkinson 《Wetlands Ecology and Management》2017,25(2):235-256
An understanding of the environmental factors that determine how clam growth varies in space and time improves effective mariculture and shellfish management. We examined the importance of temperature, salinity and chlorophyll-a in controlling the spatial pattern of Mya arenaria growth, the commercially important soft-shell clam, in the Plum Island Sound estuary in northeastern Massachusetts, USA. We collected clams (>5.08 cm) monthly during the April to November growing season from which we determined growth rate, maximum size (L-infinity), and time to reach a harvestable size. We also surveyed selected sites along the estuary to estimate the relationship between clam size and weight. We collected environmental data along the estuary, and our data were complemented with data collected and maintained by the Plum Island ecosystems long-term ecological research project. Clams reached harvestable size fastest and had the greatest L-infinity at the most oceanic site (Yacht Club) in the estuary. Clams had the smallest L-infinity and were slowest to reach the harvestable size at the least oceanic site (Railroad Meander). The spatial patterns of clam growth were best explained by a positive distribution of salinity. Salinity significantly accounted for 95 % of the spatial variation of clam growth in the estuary. Snow melt in spring increases freshwater input to the estuary and results in the lowest spring salinity during a year, and this explained the upper estuary limit of clam distribution. IPCC-projected climate change will cause sea-level rise and increasing precipitation in the northeastern USA, which will modify the spatial pattern of salinity in the region’s estuaries. Our research therefore suggests that future management of M. arenaria, an important economic resource for the local economy, should be concerned with the changes of salinity distribution under climate and land-use change. 相似文献
3.
Dal-Hoe?Koo Wenxuan?Liu Bernd?FriebeEmail authorView authors OrcID profile Bikram?S.?Gill 《Chromosoma》2017,126(4):531-540
A crossover (CO) and its cytological signature, the chiasma, are major features of eukaryotic meiosis. The formation of at least one CO/chiasma between homologous chromosome pairs is essential for accurate chromosome segregation at the first meiotic division and genetic recombination. Polyploid organisms with multiple sets of homoeologous chromosomes have evolved additional mechanisms for the regulation of CO/chiasma. In hexaploid wheat (2n = 6× = 42), this is accomplished by pairing homoeologous (Ph) genes, with Ph1 having the strongest effect on suppressing homoeologous recombination and homoeologous COs. In this study, we observed homoeologous COs between chromosome 5Mg of Aegilops geniculata and 5D of wheat in plants where Ph1 was fully active, indicating that chromosome 5Mg harbors a homoeologous recombination promoter factor(s). Further cytogenetic analysis, with different 5Mg/5D recombinants, showed that the homoeologous recombination promoting factor(s) may be located in proximal regions of 5Mg. In addition, we observed a higher frequency of homoeologous COs in the pericentromeric region between chromosome combination of rec5Mg#2S·5Mg#2L and 5D compared to 5Mg#1/5D, which may be caused by a small terminal region of 5DL homology present in chromosome rec5Mg#2. The genetic stocks reported here will be useful for analyzing the mechanism of Ph1 action and the nature of homoeologous COs. 相似文献
4.
A mini-microscope-based system for multisite detection of cardiovascular toxicity was developed. The mini-microscope consisted of an image sensor and lens module extracted from an inexpensive webcam. The flipped lens module enabled cells to be magnified and monitored during testing. The portability and compactness of this system enables short-term and potential long-term experimentation inside a conventional incubator. The toxicity test results demonstrated that the normalized beating rates of cardiac muscle cells selected from multiple regions increased over time when treated with 100 nM isoprenaline. The presented system could be a promising cost-effective cell-based testing tool for discovering and screening drugs. 相似文献
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Anondho Wijanarko Dianursanti Misri Gozan Sang Made Krisna Andika Paramita Widiastuti Heri Hermansyah Arief Budi Witarto Kazuhiro Asami Roekmijati Widaningroem Soemantojo Kazuhisa Ohtaguchi Song Seung Koo 《Biotechnology and Bioprocess Engineering》2006,11(6):484-488
Alteration of illumination with optimum carbon dioxide fixation-based curve in this research successfully enhanced the CO2-fixation (qco2) capability ofChlorella vulgaris Buitenzorg cultivated in a bubble column photo bioreactor. The level of CO2 fixation was up to 1.91 times that observed from cultivation with intensification of illumination on an optimum growth-based curve. During 144 h of cultivation, alteration of light intensity on an optimum CO2-fixation-based curve produced a qCO2 of 6.68 h?1. Increases in light intensity based on a curve of optimum CO2-fixation produced a final cell concentration of about 5.78 g/L. Both cultivation methods were carried out under ambient pressure at a temperature of 29°C with a superficial gas velocity of 2.4 m/h (UG). Cells were grown on Beneck medium in a 1.0 L Bubble Column Photo bioreactor illuminated by aPhillips Halogen Lamp (20 W/12 V/50 Hz). The inlet gas had a carbon dioxide content of 10%. 相似文献
8.
Dae Hwan Lee Ji Hyeon Ahn Joon Ha Park Bing Chun Yan Jeong-Hwi Cho In Hye Kim Jae-Chul Lee Sang-Hun Jang Myoung Hyo Lee In Koo Hwang Seung Myung Moon Bonghee Lee Jun Hwi Cho Hyung-Cheul Shin Jin Sang Kim Moo-Ho Won 《Cellular and molecular neurobiology》2013,33(5):615-624
Aging is an inevitable process that occurs in the whole body system accompanying with many functional and morphological changes. Inflammation is known as one of age-related factors, and inflammatory changes could enhance mortality risk. In this study, we compared immunoreactivities of inflammatory cytokines, such as interleukin (IL)-2 (a pro-inflammatory cytokine), its receptor (IL-2R), IL-4 (an anti-inflammatory cytokine), and its receptor (IL-4R) in the cervical and lumbar spinal cord of young adult (2–3 years old) and aged (10–12 years old) beagle dogs using immunohistochemistry and western blotting. IL-2 and IL-2R-immunoreactive nerve cells were found throughout the gray matter of the cervical and lumbar spinal cord of young adult and aged dogs. In the spinal cord neurons of the aged dog, immunoreactivity and protein levels were apparently increased compared with those in the young adult dog. Change patterns of IL-4- and IL-4R-immunoreactive cells and their protein levels were also similar to those in IL-2 and IL-2R; however, IL-4 and IL-4R immunoreactivity in the periphery of the neuronal cytoplasm in the aged dog was much stronger than that in the young adult dog. These results indicate that the increase of inflammatory cytokines and their receptors in the aged spinal cord might be related to maintaining a balance of inflammatory reaction in the spinal cord during normal aging. 相似文献
9.
Hyo Jae Kang Young Sik Park Chang-Hoon Lee Sang-Min Lee Jae-Joon Yim Chul-Gyu Yoo Young Whan Kim Sung Koo Han Jong-Yil Chai Jinwoo Lee 《The Korean journal of parasitology》2013,51(5):569-572
Dirofilariasis is a rare disease in humans. We report here a case of a 48-year-old male who was diagnosed with pulmonary dirofilariasis in Korea. On chest radiographs, a coin lesion of 1 cm in diameter was shown. Although it looked like a benign inflammatory nodule, malignancy could not be excluded. So, the nodule was resected by video-assisted thoracic surgery. Pathologically, chronic granulomatous inflammation composed of coagulation necrosis with rim of fibrous tissues and granulations was seen. In the center of the necrotic nodules, a degenerating parasitic organism was found. The parasite had prominent internal cuticular ridges and thick cuticle, a well-developed muscle layer, an intestinal tube, and uterine tubules. The parasite was diagnosed as an immature female worm of Dirofilaria immitis. This is the second reported case of human pulmonary dirofilariasis in Korea. 相似文献
10.
Lai-Ping Wong Rick?Twee-Hee Ong Wan-Ting Poh Xuanyao Liu Peng Chen Ruoying Li Kevin?Koi-Yau Lam Nisha?Esakimuthu Pillai Kar-Seng Sim Haiyan Xu Ngak-Leng Sim Shu-Mei Teo Jia-Nee Foo Linda?Wei-Lin Tan Yenly Lim Seok-Hwee Koo Linda?Seo-Hwee Gan Ching-Yu Cheng Sharon Wee Eric?Peng-Huat Yap Pauline?Crystal Ng Wei-Yen Lim Richie Soong Markus?Rene Wenk Tin Aung Tien-Yin Wong Chiea-Chuen Khor Peter Little Kee-Seng Chia Yik-Ying Teo 《American journal of human genetics》2013,92(1):52-66
Whole-genome sequencing across multiple samples in a population provides an unprecedented opportunity for comprehensively characterizing the polymorphic variants in the population. Although the 1000 Genomes Project (1KGP) has offered brief insights into the value of population-level sequencing, the low coverage has compromised the ability to confidently detect rare and low-frequency variants. In addition, the composition of populations in the 1KGP is not complete, despite the fact that the study design has been extended to more than 2,500 samples from more than 20 population groups. The Malays are one of the Austronesian groups predominantly present in Southeast Asia and Oceania, and the Singapore Sequencing Malay Project (SSMP) aims to perform deep whole-genome sequencing of 100 healthy Malays. By sequencing at a minimum of 30× coverage, we have illustrated the higher sensitivity at detecting low-frequency and rare variants and the ability to investigate the presence of hotspots of functional mutations. Compared to the low-pass sequencing in the 1KGP, the deeper coverage allows more functional variants to be identified for each person. A comparison of the fidelity of genotype imputation of Malays indicated that a population-specific reference panel, such as the SSMP, outperforms a cosmopolitan panel with larger number of individuals for common SNPs. For lower-frequency (<5%) markers, a larger number of individuals might have to be whole-genome sequenced so that the accuracy currently afforded by the 1KGP can be achieved. The SSMP data are expected to be the benchmark for evaluating the value of deep population-level sequencing versus low-pass sequencing, especially in populations that are poorly represented in population-genetics studies. 相似文献