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51.
K Kawaguchi-Nagata T Watanabe A Yamatodani M Inoue J Fujita H Okamura T Tamura K Shoji H Wada Y Kitamura 《Journal of biochemistry》1987,102(3):551-557
Injection of Staphylococcal enterotoxin A (SEA) into WBB6F1-W/WV mice genetically deficient in mast cells resulted in a 10-fold increase in the histidine decarboxylase [HDC, L-histidine carboxylase, EC 4.1.1.22] activity of their spleen. The nature of the spleen cells responsible for this increased HDC activity was studied. The HDC induction by SEA was abolished on day 1 after X-ray irradiation of the mice at 400 rad and restored by transplantation of bone marrow cells from normal WBB6F1-+/+ littermates into the X-ray irradiated WBB6F1-W/WV mice. Transplantation of cells from other organs of the normal mice, such as the thymus, mesenteric lymph node and spleen, did not restore the HDC increase significantly. Transplantation of cultured mast cells also did not restore the increase. Moreover, the high HDC activity of spleen cells induced by SEA was not affected by their treatment with anti-Thy-1,2 antibody and complement. Depletion of phagocytes from the spleen by treatment with carbonyl iron resulted in decrease in HDC activity. These results suggested that phagocytic cells derived from haemopoietic stem cells of the bone marrow were responsible for the increase in HDC activity induced by SEA. 相似文献
52.
Tie J Serizawa Y Oshida S Usami R Yoshida Y 《Human biology; an international record of research》2006,78(2):243-247
The human phosphoglycerate kinase (PGK1) gene is located within Xqll-Xql3 and is closely linked to the androgen receptor gene within a region implicated in a number of X-chromosome-linked urologic disorders. A polymorphism of a TATC short tandem repeat (STR) is present downstream from the PGK1 3' nuclease-sensitive site. We present the PGK1 flanking STR sequence and population genetic data for 190 Japanese males and 83 Japanese females. Ten STR alleles and 29 genotypes were identified in the population. Five alleles--*10, *11, *12, *13, and *14--were common in the Japanese with frequencies greater than 10%. No significant deviations from Hardy-Weinberg equilibrium were established. The power of discrimination was 0.993 for females and 0.819 for males; heterozygosity was 0.759 for females; and the polymorphic information content was 0.936. These data indicate that this STR locus shows a high degree of polymorphism in this Japanese population and may prove to be a useful genetic marker in forensic medicine, in determining the clonality of neoplasms, and potentially in studying predisposition to prostate cancer and other urologic diseases. 相似文献
53.
Akinobu Echigo Miki Hino Tadamasa Fukushima Toru Mizuki Masahiro Kamekura Ron Usami 《Aquatic biosystems》2005,1(1):1-13
Background
Natural microbial communities are extremely complex and dynamic systems in terms of their population structure and functions. However, little is known about the in situ functions of the microbial communities.Results
This study describes the application of proteomic approaches (metaproteomics) to observe expressed protein profiles of natural microbial communities (metaproteomes). The technique was validated using a constructed community and subsequently used to analyze Chesapeake Bay microbial community (0.2 to 3.0 μm) metaproteomes. Chesapeake Bay metaproteomes contained proteins from pI 4–8 with apparent molecular masses between 10–80 kDa. Replicated middle Bay metaproteomes shared ~92% of all detected spots, but only shared 30% and 70% of common protein spots with upper and lower Bay metaproteomes. MALDI-TOF analysis of highly expressed proteins produced no significant matches to known proteins. Three Chesapeake Bay proteins were tentatively identified by LC-MS/MS sequencing coupled with MS-BLAST searching. The proteins identified were of marine microbial origin and correlated with abundant Chesapeake Bay microbial lineages, Bacteroides and α-proteobacteria.Conclusion
Our results represent the first metaproteomic study of aquatic microbial assemblages and demonstrate the potential of metaproteomic approaches to link metagenomic data, taxonomic diversity, functional diversity and biological processes in natural environments. 相似文献54.
A new approach to the community-level BIOLOG assay was proposed. This assay, which we call the BIOLOG-MPN assay, is a most-probable-number (MPN) assay that uses BIOLOG plates and multiple sole carbon sources, and the profiles obtained by this assay consist of MPNs estimated for the substrates in the BIOLOG plates. In order to demonstrate the performance of the BIOLOG-MPN assay, it was applied to pure cultures, model bacterial communities that contain two strains in different ratios, and microbial community samples. MPN estimation using BIOLOG plates worked well for the substrates on which utilizers can grow at a sufficiently high rate for color development under the conditions of the assay procedure. Furthermore, the results obtained using model communities showed that the MPNs obtained reflected the mixing ratios of pure cultures in the model communities. The profiles obtained using model communities and community samples were differentiated properly by statistical analyses. The results suggest that the BIOLOG-MPN assay is a promising procedure for obtaining a quantitative picture of the community structure. 相似文献
55.
The hexadeoxynucleotide analog, L-d(CGCGCG) composed of L-deoxyribose was synthesized and clearly shown to have the same conformation and dynamic properties with natural D-d(CGCGCG) except for chirality with CD spectra. This unnatural hexanucleotide was not cleaved by bleomycin, an antitumor DNA cleaving drug, but was able to bind to the DNA binding domain of bleomycin to a similar extent with the natural one. These results strongly suggest the importance of the other moiety than the DNA binding domain for the specific DNA recognition of bleomycin. Thus, L-oligonucleotides are useful for the study of DNA-drug interactions. 相似文献
56.
Hirotaka Shoji Hideo Hagihara Keizo Takao Satoko Hattori Tsuyoshi Miyakawa 《Journal of visualized experiments : JoVE》2012,(60)
Forced alternation and left-right discrimination tasks using the T-maze have been widely used to assess working and reference memory, respectively, in rodents. In our laboratory, we evaluated the two types of memory in more than 30 strains of genetically engineered mice using the automated version of this apparatus. Here, we present the modified T-maze apparatus operated by a computer with a video-tracking system and our protocols in a movie format. The T-maze apparatus consists of runways partitioned off by sliding doors that can automatically open downward, each with a start box, a T-shaped alley, two boxes with automatic pellet dispensers at one side of the box, and two L-shaped alleys. Each L-shaped alley is connected to the start box so that mice can return to the start box, which excludes the effects of experimenter handling on mouse behavior. This apparatus also has an advantage that in vivo microdialysis, in vivo electrophysiology, and optogenetics techniques can be performed during T-maze performance because the doors are designed to go down into the floor. In this movie article, we describe T-maze tasks using the automated apparatus and the T-maze performance of α-CaMKII+/- mice, which are reported to show working memory deficits in the eight-arm radial maze task. Our data indicated that α-CaMKII+/- mice showed a working memory deficit, but no impairment of reference memory, and are consistent with previous findings using the eight-arm radial maze task, which supports the validity of our protocol. In addition, our data indicate that mutants tended to exhibit reversal learning deficits, suggesting that α-CaMKII deficiency causes reduced behavioral flexibility. Thus, the T-maze test using the modified automatic apparatus is useful for assessing working and reference memory and behavioral flexibility in mice. 相似文献
57.
Pumiko Matsui Atsuhiko Oohira Ryujiro Shoji Hiroshi Nogami 《Differentiation; research in biological diversity》1986,31(1):29-34
The sulfated glycosaminoglycans synthesized in the forelimb plates of rats on days 12, 13, 14, and 15 of gestation were characterized by their susceptibility to various glycosaminoglycan lyases. On days 12 and 13, heparan sulfate accounted for approximately 65% of the newly synthesized sulfated glycosaminoglycans. Small amounts of dermatan sulfate and chondroitin sulfates were also observed. On day 14, the relative amount of chondroitin 4-sulfate began to increase, there being a compensatory decrease in the amount of heparan sulfate. 35S-Sulfate-labeled material was extracted from day-13 forelimb plates with 4 M guanidine/HCl without proteolysis. Using ultracentrifugation on a sucrose density gradient, the extract was separated into two peaks: a light peak (L) mainly composed of heparan sulfate, and a faster-sedimenting peak (M) mainly composed of chondroitin sulfate. The cartilage-type proteoglycan (H) was first detectable on day 14 of gestation, indicating that chondrogenesis in rat forelimb plates starts on day 14 of gestation. In addition to these previously identified glycosaminoglycans or proteoglycans, we isolated an unknown component in the glycosaminoglycan preparations obtained from limb plates during these developmental stages. This component was not found in glycosaminoglycan preparations obtained either from the brain or tail of rat fetuses at the same stages. 相似文献
58.
From the root bark of Hovenia dulcis Thunb. and H. tommentella (Makino) Nakai (Rhamnaceae), three peptide alkaloids, frangulanine, hovenins-A and -B have been isolated. Hovenin-A has been shown to be des-N-methylfrangulanine (II). 相似文献
59.
Mori Hideki Masaki Takashi Tsunamoto Yoshihiro Naoe Shoji 《Journal of plant research》2020,133(2):193-203
Journal of Plant Research - Lianas have a huge influence on forest structure and function. However, it is unclear how the surrounding environment affects the establishment of liana seedlings in... 相似文献
60.
Phylogeography of Fischer’s blue,Tongeia fischeri,in Japan: Evidence for introgressive hybridization
Ekgachai Jeratthitikul Takehiro Hara Masaya Yago Tateo Itoh Min Wang Shin-ichi Usami Tsutomu Hikida 《Molecular phylogenetics and evolution》2013,66(1):316-326
The widespread lycaenid butterfly Tongeia fischeri is distributed from eastern Europe to northeastern Asia and represented by three geographically isolated populations in Japan. In order to clarify the phylogeographic history of the species, we used sequences of three mitochondrial (COI, Cyt b and ND5) and two nuclear (Rpl5 and Ldh) genes of 207 individuals collected from 55 sites throughout Japan and five sites on the Asian continent. Phylogenetic trees and the median-joining network revealed six evolutionary mitochondrial haplotype clades, which corresponded to the geographic distribution of the species. Common ancestors of Japanese T. fischeri might have come to Japan during the mid-Pleistocene by multiple dispersals of continental populations, probably via a land bridge or narrow channel between western Japan and the Korean Peninsula. The geographical patterns of variation of mitochondrial and nuclear markers are discordant in northeastern Kyushu, possibly as a result of introgressive hybridization during the ancient contact between the Kyushu and Shikoku populations in the last glacial maximum. The phylogeographic pattern of T. fischeri in Japan are probably related to the geological history, Pleistocene climatic oscillations and distribution of the host plant. 相似文献