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961.
We report a highly sensitive enzyme immunoassay for dehydroepiandrosterone (DHEA) and its sulfate (DHEA-S) using horseradish peroxidase as the label enzyme. Separation of free and bound DHEA-peroxidase conjugate was by insolubilized antibody, prepared by coupling purified IgG of goat anti-rabbit IgG serum with Sepharose 4B or a polystyrene tube. The enzyme activity was measured by the chemiluminescence reaction using luminol and hydrogen peroxide as substrate. The faint chemiluminescence was measured by a photon counter. The sensitivity was 25 pg/assay tube for DHEA and 100 pg/assay tube for DHEA-S. Upon comparison, results obtained by radioimmunoassay and this method showed good agreement; r = 0.86 for free DHEA, r = 0.92 for acid-hydrolyzed DHEA-S and r = 0.91 for solvolyzed DHEA-S. The present method is applicable in the routine determination of DHEA and DHEA-S in biological fluid. 相似文献
962.
Ichthyological Research - Plectranthias kojii sp. nov. (Perciformes: Serranidae) is described from a single specimen [49.4 mm in standard length (SL)] collected from 150 m depth off Hamahiga-jima... 相似文献
963.
Hidetoshi Ota 《Ecological Research》1994,9(2):121-130
Lepidodactylus lugubris, a parthenogenetic gekkonid lizard of possible tropical origin, occurs on Kita-Daitojima Island of the Ryukyu Archipelago
and lays eggs almost throughout the year. The oviposition season of the sympatric population of another primary tropical,
but bisexual gecko,Hemidactylus frenatus, is confined to between April and September. Laboratory experiments indicate that the hatching ratio of the egg reduces with
the decrease of incubation temperature in both species. Some eggs ofL. lugubris develop at 14°C of ambient temperature, wheras eggs ofH. frenatus always die at temperatures of 18°C or lower. Examinations of stomach contents and fat body mass in the monthly samples suggest
that food availability is not severely low for the geckos even during the winter, rejecting the previous assumption that food
stress suppresses vitellogenesis inH. frenatus. No other environmental factors that may induce reproductive seasonality as phenotypic physiological responses were detected
either. Tropical populations ofH. frenatus andL. lugubris are known to lack distinct annual reproductive cyclicity. Thus, it is probable that the East AsianH. frenatus has evolved the winter quiescence of reproduction, presumably due to the poor embryonic tolerance of low temperatures. The
absence of such seasonality in the sympatricL. lugubris seems to be attributable to its clonal nature which predicts the low genetic variability of the population from the colonization
stage. 相似文献
964.
Atsushi Tominaga Masafumi Matsui Naoko Shimoji Wichase Khonsue Chi‐Shiun Wu Mamoru Toda Koshiro Eto Kanto Nishikawa Hidetoshi Ota 《Zoologica scripta》2019,48(4):440-453
The Ryukyu Archipelago, located at the southwestern part of Japan, is known as a group of continental islands and harbours many endemic taxa, supposedly reflecting its fairly long isolation from the Eurasian continent, Taiwan and the Japanese main islands. Microhyla okinavensis has been known as an endemic member of the terrestrial fauna of this archipelago. Molecular phylogenetic analyses using samples from nearly all island populations of the species and representative samples of other east Asian congeneric species revealed that M. okinavensis consists of four distinct subclades, of which the Amami, Okinawa and Miyako subclades, though exhibiting distinct genetic differentiations from each other, formed a monophyletic group (clade A). The remaining Yaeyama subclade was exclusively sister to M. mixtura from inland China, forming another monophyletic group (clade B), rendering M. okinavensis in the current definition paraphyletic. These results, as well as estimated dates of divergence from related taxa, indicate that M. okinavensis actually includes more than one distinct species. The results indicate that M. okinavensis and M. mixtura are relict species with disjunct distributions which had been most probably caused by invasion of M. fissipes in intervening areas. 相似文献
965.
Genetica - Tanytarsini is a large tribe of Chironomidae with at least 11 recorded marine species grouped in three genera. In this study, we performed a phylogenic analysis using molecular data from... 相似文献
966.
Chie Tanaka Sachiko Ito Naomi Nishio Yasuhiro Kodera Hidetoshi Sakurai Haruhiko Suzuki Akimasa Nakao Ken-Ichi Isobe 《Transgenic research》2010,19(4):637-645
Wound healing consists of sequential steps of tissue repair, and cell migration is particularly important. In order to analyze
the potential function of growth arrest and DNA damage inducible protein 34 (GADD34) in tissue repair, we performed in vitro
and in vivo wound healing experiments. In an in vitro scratch assay, GADD34 knockout (KO) mouse embryonic fibroblasts (MEFs)
had higher migration rates than did wild type (WT) MEFs. Furthermore, the rate of wound closure was faster in GADD34 KO MEFs
than in WT MEFs. Using in vivo punch biopsy assays, GADD34 KO mice had accelerated wound healing compared to WT mice. WT mice
expressed higher amounts of myosin IIA in migrating macrophages and myofibroblasts than did GADD34 KO mice. These results
indicate that GADD34 negatively regulates cell migration in wound healing via expression of myosin IIA. 相似文献
967.
Junko Kawashima Kazuko Nakajo Jumpei Washio Gen Mayanagi Hidetoshi Shimauchi Nobuhiro Takahashi 《Microbiology and immunology》2013,57(12):797-804
Actinomyces are predominant oral bacteria; however, their cariogenic potential in terms of acid production and fluoride sensitivity has not been elucidated in detail and compared with that of other caries‐associated oral bacteria, such as Streptococcus. Therefore, this study aimed to elucidate and compare the acid production and growth of Actinomyces and Streptococcus in the presence of bicarbonate and fluoride to mimic conditions in the oral cavity. Acid production from glucose was measured by pH‐stat at pH 5.5 and 7.0 under anaerobic conditions. Growth rate was assessed by optical density in anaerobic culture. Although Actinomyces produced acid at a lower rate than did Streptococcus, their acid production was more tolerant of fluoride (IDacid production 50 = 110–170 ppm at pH 7.0 and 10–13 ppm at pH 5.5) than that of Streptococcus (IDacid production 50 = 36–53 ppm at pH 7.0 and 6.3–6.5 ppm at pH 5.5). Bicarbonate increased acid production by Actinomyces with prominent succinate production and enhanced their fluoride tolerance (IDacid production 50 = 220–320 ppm at pH 7.0 and 33–52 ppm at pH 5.5). Bicarbonate had no effect on these variables in Streptococcus. In addition, although the growth rate of Actinomyces was lower than that of Streptococcus, Actinomyces growth was more tolerant of fluoride (IDgrowth 50 = 130–160 ppm) than was that of Streptococcus (IDgrowth 50 = 27–36 ppm). These results indicate that oral Actinomyces are more tolerant of fluoride than oral Streptococcus, and bicarbonate enhances the fluoride tolerance of oral Actinomyces. Because of the limited number of species tested here, further study is needed to generalize these findings to the genus level. 相似文献
968.
Reina Uno Mami Kondo Takashi Yuasa Kiyoshi Yamauchi Hihumi Tsuruga Hidetoshi B. Tamate Masaaki Yoneda 《Population Ecology》2012,54(4):509-519
Non-invasive DNA genotyping using hair samples has become a common method in population surveys of Asiatic black bears (Ursus thibetanus) in Japan; however, the accuracy of the genotyping data has rarely been discussed in empirical studies. Therefore, we conducted a large-scale pilot study to examine genotyping accuracy and sought an efficient way of error-checking hair-trapping data. We collected 2,067 hair samples, successfully determined the genotypes of 1,245 samples, and identified 295 individuals. The genotyping data were further divided into 3 subsets of data according to the number of hairs used for DNA extraction in each sample (1–4, 5–9, and ≥10 hairs), and the error rates of allelic dropout and false alleles were estimated for each subset using a maximum likelihood method. The genotyping error rates in the samples with ≥10 hairs were found to be lower than those in the samples with 1–4 and 5–9 hairs. The presence of erroneous genotypes among the identified individuals was further checked using a post hoc goodness-of-fit test that determined the match between the expected and observed frequencies of individual homozygotes at 0–6 loci. The results indicated the presence of erroneous genotypes, possibly as a result of allelic dropout, in the samples. Therefore, for improved accuracy, it is recommended that samples containing ≥10 hairs should be used for genotyping and a post hoc goodness-of-fit test should be performed to exclude erroneous genotypes before proceeding with downstream analysis such as capture-mark-recapture estimation. 相似文献
969.
Effects of prostaglandins (PGs) of the E series on growth and differentiation of murine myeloid leukemic cell line M1 were studied. PGE1, but not PGE2, inhibited the growth of M1 cells. PGE2 neither inhibited nor augmented the antiproliferative effect of PGE1. PGE1 augmented the differentiation of M1 cells into macrophage-like cells induced by interleukin 6. PGE2, however, did not exhibit any effect on the differentiation. PGE1 caused a marked increase in intracellular cAMP level in M1 cells, whereas PGE2 had no effect. These results indicate that M1 cells are able to respond only to PGE1. Radiolabeled PGE1 binding experiments, however, revealed that there was no specific binding in M1 cells, suggesting that the cells express low numbers of receptors or very low affinity receptors specific for PGE1. Stable agonists of PGI2, iloprost, cicaprost or carbacyclin, also potently inhibited the growth of M1 cells. These findings suggest that PGE1 as well as PGI2 may play a role in the differentiation of monocyte-macrophage lineage cells. 相似文献
970.
The substrate specificities of cinnamyl alcohol dehydrogenase (CAD) of angiosperms and gymnosperms were examined using coniferaldehyde and sinapaldehyd 相似文献