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61.
Sakamoto J Morita S Oba K Matsui T Kobayashi M Nakazato H Ohashi Y;Meta-Analysis Group of the Japanese Society for Cancer of the Colon Rectum 《Cancer immunology, immunotherapy : CII》2006,55(4):404-411
The benefits of immunochemotherapy employing the biological response modifier polysaccharide K (PSK) for patients with curatively
resected colorectal cancer was reassessed by means of a meta-analysis of data with center randomization from 1,094 patients
enrolled in three clinical trials. In all three trials, patients were followed up for at least 5 years after surgery and enrollment
of the last patient and outcomes for standard chemotherapy were compared with those for chemotherapy plus PSK. The endpoints
were overall survival and disease-free survival; and intent-to-treat analysis was performed without patient exclusion. Data
were analyzed using the weighted average of the individual log hazard ratios. The overall survival risk ratio for all eligible
patients was 0.71 (95% confidence interval (CI) : 0.55–0.90; P=0.006), and the disease-free survival risk ratio was 0.72 (95% CI: 0.58–0.90; P=0.003). The results of this meta-analysis suggest that adjuvant immunochemotherapy with PSK can improve both survival and
disease-free survival of patients with curatively resected colorectal cancer. 相似文献
62.
The world-wide debate on land degradation in arid lands, usually linked to local land use practices, does not reflect methodological
advancements in terms of assessments and monitoring that integrate local communities’ knowledge with ecological methods. In
this paper, we evaluated the efficacy of three different methods related to herder assessments and monitoring of land degradation;
herder knowledge and ecological methods of assessing impacts of livestock grazing along gradients of land use from settlement
and joint monitoring of selected marked transects to understand long-term vegetation changes in southwestern Marsabit northern
Kenya. The performance of each method was carefully evaluated and interpreted in terms of the indicators used by herders and
ecologists. Herder interpretations were then related to ecologists’ empirical analysis of land degradation. The Rendille nomads
have a complex understanding of land degradation which combines environmental and livestock productivity indicators, compared
to conventional scientific approaches that use plant-based indicators alone. According to the herders, the grazing preference
of various livestock species (e.g., grazers versus browsers) influences perceptions of land degradation, suggesting degradation
is a relative term. The herders distinguished short-term changes in vegetation cover from long-term changes associated with
over-exploitation. They attributed current environmental degradation around pastoral camps, which shift land use between the
alternating wet and dry seasons, to year-round grazing. We deduced from long-term observation that herders interpret vegetation
changes in terms of rainfall variability, utilitarian values and intensification of land use. Long-term empirical data (23 years)
from repeated sampling corroborated herder interpretations. Land degradation was mostly expressed in terms of declines in
woody plant species, while spatial and temporal dynamics of herbaceous species reflected the effects of seasonality. The efficacy
of the three methods were inferred using explanatory strengths of ecological theory; insightfulness of the methods for describing
land degradation and the likelihood of using the methods for promoting local community participation in the implementation
of the UN Convention on Combating Desertification (CCD) and the Convention on Biological Diversity (CBD). 相似文献
63.
Yoshinori Masukawa Hirofumi Narita Hirayuki Sato Ayano Naoe Naoki Kondo Yoshiya Sugai Tsuyoshi Oba Rika Homma Junko Ishikawa Yutaka Takagi Takashi Kitahara 《Journal of lipid research》2009,50(8):1708-1719
One of the key challenges in lipidomics is to quantify lipidomes of interest, as it is practically impossible to collect all authentic materials covering the targeted lipidomes. For diverse ceramides (CER) in human stratum corneum (SC) that play important physicochemical roles in the skin, we developed a novel method for quantification of the overall CER species by improving our previously reported profiling technique using normal-phase liquid chromatography-electrospray ionization-mass spectrometry (NPLC-ESI-MS). The use of simultaneous selected ion monitoring measurement of as many as 182 kinds of molecular-related ions enables the highly sensitive detection of the overall CER species, as they can be analyzed in only one SC-stripped tape as small as 5 mm × 10 mm. To comprehensively quantify CERs, including those not available as authentic species, we designed a procedure to estimate their levels using relative responses of representative authentic species covering the species targeted, considering the systematic error based on intra-/inter-day analyses. The CER levels obtained by this method were comparable to those determined by conventional thin-layer chromatography (TLC), which guarantees the validity of this method. This method opens lipidomics approaches for CERs in the SC. 相似文献
64.
Soichi Osozawa Yuichi Oba Hyeok‐Yeong Kwon John Wakabayashi 《Biological journal of the Linnean Society. Linnean Society of London》2015,116(2):412-422
We performed molecular phylogenetic analyses based on the mitochondrial COI gene (687 bp) and the nuclear 28S rRNA gene (715 bp) and reconstructed phylogenetic trees of the Pyrocoelia fireflies in the Ryukyu Islands and eastern Asia. Age calibration was done using a robust geological constraint: the Okinawa trough and associated straits began to rift at 1.55 Ma, isolating the Ryukyu Islands from the Chinese continent, Japanese islands, Taiwan island and some of the islands from each other. We suggest that the physical isolation of these islands began to generate the allopatric speciation within these islands, so the timing of this isolation was assigned to an appropriate node. The topology is completely concordant among phylogenetic trees reconstructed using MEGA (maximum‐likelihood), raxmlGUI (maximum‐likelihood) and BEAST (Bayesian inference; including combined analysis of COI and 28S rRNA genes). Two lineages are recognized, related to their emergence time; spring to summer, and autumn. In each lineage, vicariance is inferred to have begun at 1.55 Ma from our phylogenetic and geological analyses. In lineage 1, P. oshimana (Amami), P. matsumurai (Okinawa), P. discicollis (W. Japan), P. fumosa (E. Japan) and P. abdominalis (Yaeyama) were differentiated. In lineage 2, P. rufa (Tsushima and Korea), P. miyako (Miyako‐jima), P. atripennis (Ishigaki‐jima) and P. praetexta (Taiwan and HongKong) were differentiated. Pyrocoelia analis (Taiwan and China) emerges throughout the year except for winter, and constitutes another lineage. We suggest that Pyrocoelia fireflies differentiated at 2 Ma to generate these three lineages. The base substitution rate for the COI gene is estimated as 4.48% Myr–1 and that for the 28S rRNA gene is 0.394% Myr–1, and these rates were used in a combined BEAty analysis in BEAST. 相似文献
65.
66.
Zooxanthellamide B, C(128)H(220)N(2)O(53)S(2), a polyhydroxy secondary metabolite, was isolated from a cultured marine dinoflagellate of the genus Symbiodinium. A detailed 2D NMR analysis revealed the chemical structure as a delta-lactone analogue of zooxanthellamide A, which had previously been isolated from the same dinoflagellate by us. The relative configuration of the delta-lactone moiety was determined by NOE experiments and a coupling constant analysis, and that of other ring systems was found to be the same as zooxanthellamide A by the chemical correlation between zooxanthellamides A and B. 相似文献
67.
Callus was induced from sweet potato root tissue on an agarmedium containing Heller's minerals, vitamins, 2,4-D, yeastextract and sucrose. Furano-terpenes were scarcely detectedin the callus. However, when the callus was transferred to aliquid culture medium and incubated with reciprocal shaking,furano-terpenes were rapidly produced mainly in the culturemedium. Furano-terpene production by the cell culture was suppressedby addition of Ceratocystis fimbriata spores or HgCl2 to theculture medium. Yeast extract and sucrose in the culture mediumwere important for furano-terpene production. 3-Hydroxy-3-methylglutarylcoenzyme A (HMG-CoA) reductase activity increased in the cells,followed by the production of furano-terpenes. The TLC patternof furano-terpenes produced by the cell culture was essentiallythe same as that produced by sweet potato root tissue infectedby C. fimbriata or treated with HgCl2, but the quantitativeproportion of the individual furano-terpenes in the former differedmarkedly from that in the latter. (Received January 11, 1979; ) 相似文献
68.
Time course analysis of RNA contents of tissue discs after cuttingdisclosed a remarkable increase in total RNA during the first12 hr after cutting and this elevated level remained unchangedfor 48 hr. The elevated RNA level at 24 hr of incubation wasnot changed by subsequent HgCl2 treatment. The incorporationrate of the label from 3H-uridine into RNA rapidly increasedimmediately after cutting and reached a maximum at about 9 hrof incubation, then decreased sharply until 24 hr and continuedto decrease gradually thereafter. The incorporation rate at24 hr of incubation was not changed by subsequent HgCl2 treatment.The results of polyacrylamide gel electrophoresis indicatedthat bulk RNA was synthesized most actively at 9 hr of incubationthen the rate of RNA synthesis decreased gradually. (Received August 26, 1977; ) 相似文献
69.
Oba Y Hirai T Yoshiura Y Kobayashi T Nagahama Y 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2001,129(2-3):441-448
We have cloned and characterized, for the first time in fish, two different gonadotropin receptors (GTHR) and a single thyrotropin receptor (TSHR) from amago salmon (Oncorhynchus rhodurus) and Nile tilapia (Oreochromis niloticus). Phylogenetic analyses and intron/exon structure suggest that the two GTHRs in fish are comparable to tetrapod follicle stimulating hormone and luteinizing hormone receptors. Temporal and spatial expression patterns, examined by Northern blot analysis and in situ hybridization, paralleled those seen in mammals and birds. Consequently, genetic and functional divergence of two GTHRs and TSHR probably occurred before the teleost and tetrapod split. 相似文献
70.