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1.
2.
Application of Fluorescent Antibody for Detecting Capsular Substances in Staphylococcus aureus 总被引:2,自引:2,他引:0
K. YOSHIDA M. TAKAHASHI T. OHTOMO Y. MINEGISHI Y. ICHIMAN K. HAGA E. KONO C. L. SAN CLEMENTE 《Journal of applied microbiology》1979,46(1):147-152
A fluorescent antibody technique was developed for the determination of the capsular-type of strains of Staphylococcus aureus. It compared favourably with the method using serum-soft agar (Yoshida 1972). With the new technique, many populations of encapsulated and unencapsulated strains were investigated. Of 1421 fresh isolates of Staph. aureus , 54 were encapsulated and among these 54·8% and 48·1% were mono- and polyvalent, respectively. Capsular-type antigens A and B were found in 92·5% and 44·4% of strains respectively; capsular-types C and D were found relatively infrequently. In the other group, of unencapsulated strains, capsular-type antigen production was demonstrated in 125 out of 163 strains examined. Mono- and polyvalent capsular-types (A and B antigen producing strains) comprised 77·6% and 22·4%. respectively. In these capsular-types A and B were found in 54·4% and 62·4%, respectively: capsular-type antigen C and D producing strains were again infrequent. These results indicate that a majority of ordinary Staph . aureus strains produce capsular-type antigens although isolation of the encapsulated strains is infrequent. 相似文献
3.
Takuma Watanobe Naotaka Ishiguro Naohiko Okumura Masuo Nakano Akira Matsui Hitomi Hongo Hiroshi Ushiro 《Journal of molecular evolution》2001,52(3):281-289
The Kabukai A site (5 to 8C A.D.) of the Okhotsk cultural area is on Rebun Island, a small island near the coast, north–northwest
of Hokkaido, Japan. Specimens of Sus scrofa, called the Sakhalin pig, were discovered in five cultural layers at the Kabukai A site. Ancient DNA was extracted from the
remains of 42 Sakhalin pig bones. Thirty-nine nucleotide sequences of the 574-bp mitochondrial DNA control region, estimated
to have originated from at least 21 individuals, were amplified and analyzed phylogenetically. Nine distinct haplotypes (A1,
A2, A3, B1, B2, C1, C2, D1, and D2) from this site were classified into four haplotype groups (A, B, C, and D) by parsimonious
network analysis. Phylogenetic analysis of 9 ancient and 55 modern haplotypes indicated that the population of Sakhalin pigs
at the Kabukai A site belonged to two distinct clusters; haplotype groups A and B formed a cluster comprised only of themselves,
and haplotype groups C and D belonged to the cluster of one of the two genetic groups of Japanese wild boars uniquely distributed
in the western part of Japan, including one northeast Mongolian wild boar. Analysis of the haplotype distribution among three
archaeological sites and their historical transitions among the five layers reflecting the cultural periods at the Kabukai
A site suggests that the Sakhalin pig populations were introduced from Sakhalin island and the Amur River basin in the northeastern
Eurasian continent together with some cultural influences.
Received: 18 April 2000 / Accepted: 24 November 2000 相似文献
4.
Overexpression of an Arabidopsis thaliana galactinol synthase gene improves drought tolerance in transgenic rice and increased grain yield in the field 下载免费PDF全文
Michael Gomez Selvaraj Takuma Ishizaki Milton Valencia Satoshi Ogawa Beata Dedicova Takuya Ogata Kyouko Yoshiwara Kyonoshin Maruyama Miyako Kusano Kazuki Saito Fuminori Takahashi Kazuo Shinozaki Kazuo Nakashima Manabu Ishitani 《Plant biotechnology journal》2017,15(11):1465-1477
Drought stress has often caused significant decreases in crop production which could be associated with global warming. Enhancing drought tolerance without a grain yield penalty has been a great challenge in crop improvement. Here, we report the Arabidopsis thaliana galactinol synthase 2 gene (AtGolS2) was able to confer drought tolerance and increase grain yield in two different rice (Oryza sativa) genotypes under dry field conditions. The developed transgenic lines expressing AtGolS2 under the control of the constitutive maize ubiquitin promoter (Ubi:AtGolS2) also had higher levels of galactinol than the non‐transgenic control. The increased grain yield of the transgenic rice under drought conditions was related to a higher number of panicles, grain fertility and biomass. Extensive confined field trials using Ubi:AtGolS2 transgenic lines in Curinga, tropical japonica and NERICA4, interspecific hybrid across two different seasons and environments revealed the verified lines have the proven field drought tolerance of the Ubi:AtGolS2 transgenic rice. The amended drought tolerance was associated with higher relative water content of leaves, higher photosynthesis activity, lesser reduction in plant growth and faster recovering ability. Collectively, our results provide strong evidence that AtGolS2 is a useful biotechnological tool to reduce grain yield losses in rice beyond genetic differences under field drought stress. 相似文献
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Maiko Matsushita Yohei Otsuka Naoya Tsutsumida Chiaki Tanaka Akane Uchiumi Koji Ozawa Takuma Suzuki Daiju Ichikawa Hiroyuki Aburatani Shinichiro Okamoto Yutaka Kawakami Yutaka Hattori 《PloS one》2016,11(1)
The homeobox protein, PEPP2 (RHOXF2), has been suggested as a cancer/testis (CT) antigen based on its expression pattern. However, the peptide epitope of PEPP2 that is recognized by cytotoxic T cells (CTLs) is unknown. In this study, we revealed that PEPP2 gene was highly expressed in myeloid leukemia cells and some other hematological malignancies. This gene was also expressed in leukemic stem-like cells. We next identified the first reported epitope peptide (PEPP2271-279). The CTLs induced by PEPP2271-279 recognized PEPP2-positive target cells in an HLA-A*24:02-restricted manner. We also found that a demethylating agent, 5-aza-2’-deoxycytidine, could enhance PEPP2 expression in leukemia cells but not in blood mononuclear cells from healthy donors. The cytotoxic activity of anti-PEPP2 CTL against leukemic cells treated with 5-aza-2’-deoxycytidine was higher than that directed against untreated cells. These results suggest a clinical rationale that combined treatment with this novel antigen-specific immunotherapy together with demethylating agents might be effective in therapy-resistant myeloid leukemia patients. 相似文献
7.
Objective
We examined metabolic and endocrine responses during rest and exercise in moderate hypoxia over a 7.5 h time courses during daytime.Methods
Eight sedentary, overweight men (28.6±0.8 kg/m2) completed four experimental trials: a rest trial in normoxia (FiO2 = 20.9%, NOR-Rest), an exercise trial in normoxia (NOR-Ex), a rest trial in hypoxia (FiO2 = 15.0%, HYP-Rest), and an exercise trial in hypoxia (HYP-Ex). Experimental trials were performed from 8:00 to 15:30 in an environmental chamber. Blood and respiratory gas samples were collected over 7.5 h. In the exercise trials, subjects performed 30 min of pedaling exercise at 60% of VO2max at 8:00, 10:30, and 13:00, and rested during the remaining period in each environment. Standard meals were provided at 8:30, 11:00, and 13:30.Results
The areas under the curves for blood glucose and serum insulin concentrations over 7.5 h did not differ among the four trials. At baseline, %carbohydrate contribution was significantly higher in the hypoxic trials than in the normoxic trials (P<0.05). Although exercise promoted carbohydrate oxidation in the NOR-Ex and HYP-Ex trials, %carbohydrate contribution during each exercise and post-exercise period were significantly higher in the HYP-Ex trial than in the NOR-Ex trial (P<0.05).Conclusion
Three sessions of 30 min exercise (60% of VO2max) in moderate hypoxia over 7.5 h did not attenuate postprandial glucose and insulin responses in young, overweight men. However, carbohydrate oxidation was significantly enhanced when the exercise was conducted in moderate hypoxia. 相似文献8.
9.
Takuma Tanada 《Physiologia plantarum》1984,61(1):35-37
The interactions of green or red light with blue light on the dark closing of Albizzia julibrissin Durazz. pinnules have been investigated. Irradiations at 430, 450 and 470 nm progressively delay dark closing with increasing photon fluence rates. Red or green light alone has no effect. However, when the blue fluence rate is low, both red and green light interact with it and increase the delaying effect of the blue light. When the blue fluence rate is high, green light interacts with it to negate some of the effectiveness of the blue light, while red light has no effect. This is similar to results obtained previously with far-red light. It is suggested that the same unidentified photoreceptor is operating in both the far-red and blue regions. The results also indicate the presence of a blue-only absorbing photoreceptor whose action is increased by phytochrome. 相似文献
10.