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991.
Ochi A Ishimura E Tsujimoto Y Kakiya R Tabata T Mori K Shoji T Yasuda H Nishizawa Y Inaba M 《Biological trace element research》2011,143(2):825-834
Trace element disturbance is often observed in hemodialysis patients. While trace element concentrations have been reported
in blood samples from hemodialysis patients, they have not been well investigated in scalp hair. In the present study, 22
trace elemental concentrations were measured by inductively coupled plasma-atomic emission spectrometry in the scalp hair
of 80 male hemodialysis patients and compared with those of 100 healthy male subjects. In hemodialysis patients, the concentrations
of beryllium, arsenic, magnesium, chromium, manganese, iron, selenium, molybdenum, iodine, vanadium, and cobalt were significantly
higher than those in healthy subjects, while lead, mercury, copper, germanium, and bromine were significantly lower than those
in the former group. No significant differences were observed for lithium, aluminum, cadmium, zinc, boron, or nickel. There
were significant positive correlations between the duration of hemodialysis and the magnesium and manganese concentrations.
There was a significant negative correlation between cadmium concentration and the duration of hemodialysis. There were significant
positive correlations between dialysis efficacy (Kt/V) and magnesium, manganese, zinc, and selenium concentrations. In conclusion,
trace element concentrations of the scalp hair are different between hemodialysis patients and healthy subjects. Essential
trace elements, such as magnesium, manganese, zinc, and selenium, may be affected by the duration of hemodialysis and Kt/V. 相似文献
992.
Carassius RFamide (C-RFa) is a peptide, isolated originally from the brain of Japanese crucian carp and sharing homologies with mammalian prolactin-releasing peptides. From the physiological aspect, it is known that C-RFa has contraction-promoting action on fish intestines, but its localization in peripheral tissues is unknown. We observed the localization of C-RFa in teleost guts using an immunohistochemical technique. C-RFa-like immunoreactive (irC-RFa) sites were observed in not only the smooth muscle cells in the longitudinal muscle layer, but also in both Auerbach's and Meissner's nerve plexus in the stomach, pyloric ceca and intestine. In epithelial mucous cells, irC-RFa sites were observed in the surface mucous cells in the stomach in freshwater fish (FW), and in the goblet cells of the apical sites in the villi of the pyloric ceca and intestine in all fish. In the stomach, irC-RFa sites were found in the fundic glands of the body regions in seawater (SW) and brackish water (BW) fish, but not in FW fish. This study confirmed that one of the functions of C-RFa is the smooth muscle contraction of the longitudinal muscle layer in digestive organs. We suggest that C-RFa may have functional roles in both central and peripheral neurotransmission. In addition, it appears that the difference in C-RFa localization of SW, BW, and FW fish reflects the adaptation of the stomach function to different salinity habitats. 相似文献
993.
Cyclic AMP potentiates vascular endothelial cadherin-mediated cell-cell contact to enhance endothelial barrier function through an Epac-Rap1 signaling pathway 下载免费PDF全文
Fukuhara S Sakurai A Sano H Yamagishi A Somekawa S Takakura N Saito Y Kangawa K Mochizuki N 《Molecular and cellular biology》2005,25(1):136-146
Cyclic AMP (cAMP) is a well-known intracellular signaling molecule improving barrier function in vascular endothelial cells. Here, we delineate a novel cAMP-triggered signal that regulates the barrier function. We found that cAMP-elevating reagents, prostacyclin and forskolin, decreased cell permeability and enhanced vascular endothelial (VE) cadherin-dependent cell adhesion. Although the decreased permeability and the increased VE-cadherin-mediated adhesion by prostacyclin and forskolin were insensitive to a specific inhibitor for cAMP-dependent protein kinase, these effects were mimicked by 8-(4-chlorophenylthio)-2'-O-methyladenosine-3', 5'-cyclic monophosphate, a specific activator for Epac, which is a novel cAMP-dependent guanine nucleotide exchange factor for Rap1. Thus, we investigated the effect of Rap1 on permeability and the VE-cadherin-mediated cell adhesion by expressing either constitutive active Rap1 or Rap1GAPII. Activation of Rap1 resulted in a decrease in permeability and enhancement of VE-cadherin-dependent cell adhesion, whereas inactivation of Rap1 had the counter effect. Furthermore, prostacyclin and forskolin induced cortical actin rearrangement in a Rap1-dependent manner. In conclusion, cAMP-Epac-Rap1 signaling promotes decreased cell permeability by enhancing VE-cadherin-mediated adhesion lined by the rearranged cortical actin. 相似文献
994.
Anti-cyanobacterial fatty acids released from <Emphasis Type="Italic">Myriophyllum spicatum</Emphasis> 总被引:1,自引:0,他引:1
This study was carried out to identify unknown allelochemicals released from Myriophyllum spicatum and to investigate their anti-cyanobacterial effects. A series of analyses of culture solutions and methanol extracts of M. spicatum using gas chromatograph equipped with a mass selective detector revealed that M. spicatum released fatty acids, specifically, nonanoic, tetradecanoic, hexadecanoic, octadecanoic, and octadecenoic acids. Nonanoic, cis-6-octadecenoic, and cis-9-octadecenoic acids significantly inhibited growth of Microcystis aeruginosa, whereas tetradecanoic, hexadecanoic, and octadecanoic acids did not show any effect. When the inhibitory effect of nonanoic acid was compared with those of 4 polyphenols and eugeniin, which are anti-cyanobacterial compounds previously reported to be released by M. spicatum, nonanoic acid was found to be the most inhibitory to M. aeruginosa. These results indicate that not only polyphenols and eugeniin but also fatty acids such as nonanoic acid must be studied to reveal how M. spicatum exerts its allelopathic effect on M. aeruginosa. 相似文献
995.
Potential for biogeochemical cycling of sulfur,iron and carbon within massive sulfide deposits below the seafloor 下载免费PDF全文
Shingo Kato Kei Ikehata Takazo Shibuya Tetsuro Urabe Moriya Ohkuma Akihiko Yamagishi 《Environmental microbiology》2015,17(5):1817-1835
Seafloor massive sulfides are a potential energy source for the support of chemosynthetic ecosystems in dark, deep‐sea environments; however, little is known about microbial communities in these ecosystems, especially below the seafloor. In the present study, we performed culture‐independent molecular analyses of sub‐seafloor sulfide samples collected in the Southern Mariana Trough by drilling. The depth for the samples ranged from 0.52 m to 2.67 m below the seafloor. A combination of 16S rRNA and functional gene analyses suggested the presence of chemoautotrophs, sulfur‐oxidizers, sulfate‐reducers, iron‐oxidizers and iron‐reducers. In addition, mineralogical and thermodynamic analyses are consistent with chemosynthetic microbial communities sustained by sulfide minerals below the seafloor. Although distinct bacterial community compositions were found among the sub‐seafloor sulfide samples and hydrothermally inactive sulfide chimneys on the seafloor collected from various areas, we also found common bacterial members at species level including the sulfur‐oxidizers and sulfate‐reducers, suggesting that the common members are widely distributed within massive sulfide deposits on and below the seafloor and play a key role in the ecosystem function. 相似文献
996.
Begum S Shibagaki M Furusawa O Nakaba S Yamagishi Y Yoshimoto J Jin HO Sano Y Funada R 《Planta》2012,235(1):165-179
The cold stability of microtubules during seasons of active and dormant cambium was analyzed in the conifers Abies firma, Abies sachalinensis and Larix leptolepis by immunofluorescence microscopy. Samples were fixed at room temperature and at a low temperature of 2–3°C to examine the
effects of low temperature on the stability of microtubules. Microtubules were visible in cambium, xylem cells and phloem
cells after fixation at room temperature during seasons of active and dormant cambium. By contrast, fixation at low temperature
depolymerized microtubules in cambial cells, differentiating tracheids, differentiating xylem ray parenchyma and phloem ray
parenchyma cells during the active season. However, similar fixation did not depolymerize microtubules during cambial dormancy
in winter. Our results indicate that the stability of microtubules in cambial cells and cambial derivatives at low temperature
differs between seasons of active and dormant cambium. Moreover, the change in the stability of microtubules that we observed
at low temperature might be closely related to seasonal changes in the cold tolerance of conifers. In addition, low-temperature
fixation depolymerized microtubules in cambial cells and differentiating cells that had thin primary cell walls, while such
low-temperature fixation did not depolymerize microtubules in differentiating secondary xylem ray parenchyma cells and tracheids
that had thick secondary cell walls. The stability of microtubules at low temperature appears to depend on the structure of
the cell wall, namely, primary or secondary. Therefore, we propose that the secondary cell wall might be responsible for the
cold stability of microtubules in differentiating secondary xylem cells of conifers. 相似文献
997.
Kazuhiro Azami Mariko Takemoto Yasunori Otsuka Satoshi Yamagishi Shigekazu Nakazawa 《Landscape and Ecological Engineering》2012,8(1):81-105
The immediate impact of damming appears most notably at the first filling of water, when the dam blocks the river and a lake
suddenly forms. In this review, the changes in meteorology, plant communities, birds and fishes surrounding initial impoundment
of Miharu Dam, constructed in an Asian Monsoon region, are summarised based on previous papers and subsequent field research.
Although wind and temperature changes were investigated, land and lake wind occur due to the different thermal properties
between the land and lake, and this type of wind often occurs at large lakes such as Glen Canyon Dam Reservoir or Lake Biwa.
The size of Miharu Dam Reservoir (ponding area 2.9 km2) was insufficient to cause land–lake air differentials. Therefore, wind direction and air temperature were unaffected. Mountain
winds weakened at the lake centre and near the dam body. Changes in vegetation were especially diverse at the drawdown zone
(the slopes above and below the normal water level). On slopes above this zone, trees died and species composition changed
due to submergence. Within the drawdown zone, the pre-existing plant community disappeared, and flood-resistant plants such
as Salix subfragilis increased. The natatorial bird population continued to grow for 4 years after dam reservoir emergence and stabilised thereafter.
Every year, the majority of natatorial birds utilising the dam reservoir as a resting area were ducks, but populations of
diving ducks fluctuated depending on water level and iced area. After impoundment, the fish populations increased. As in most
dam reservoirs in Japan, populations of invasive fish species such as Micropterus salmoides and Lepomis macrochirus increased. However, spawning grounds dried up during low-water-level seasons, suggesting that regulating water levels may
help reduce invasive species. 相似文献
998.
Chiho Sato Atsushi Sekiguchi Masaaki Kawai Yuka Kotozaki Rui Nouchi Hiroshi Tada Hikaru Takeuchi Takanori Ishida Yasuyuki Taki Ryuta Kawashima Noriaki Ohuchi 《PloS one》2015,10(11)
Objective
The primary purpose of this study was to clarify the influence of the early response to surgery on brain structure and cognitive function in patients with breast cancer. It was hypothesized that the structure of the thalamus would change during the early response after surgery due to the effects of anesthesia and would represent one aspect of an intermediate phenotype of postoperative cognitive dysfunction (POCD).Methods
We examined 32 postmenopausal females with breast cancer and 20 age-matched controls. We assessed their cognitive function (attention, memory, and executive function), and performed brain structural MRI 1.5 ± 0.5 days before and 5.6 ± 1.2 days after surgery.Results
We found a significant interaction between regional grey matter volume (rGMV) in the thalamus (P < 0.05, familywise error (FWE), small volume correction (SVC)) and one attention domain subtest (P = 0.001, Bonferroni correction) after surgery in the patient group compared with the control group. Furthermore, the changes in attention were significantly associated with sevoflurane anesthetic dose (r 2 = 0.247, β = ‒0.471, P = 0.032) and marginally associated with rGMV changes in the thalamus (P = 0.07, FWE, SVC) in the Pt group.Conclusion
Our findings suggest that alterations in brain structure, particularly in the thalamus, may occur shortly after surgery and may be associated with attentional dysfunction. This early postoperative response to anesthesia may represent an intermediate phenotype of POCD. It was assumed that patients experiencing other risk factors of POCD, such as the severity of surgery, the occurrence of complications, and pre-existing cognitive impairments, would develop clinical POCD with broad and multiple types of cognitive dysfunction. 相似文献999.
Shinichiro Izuta Masaaki Ueki Masaki Ueno Kahoru Nishina Shunichi Shiozawa Nobuhiro Maekawa 《Biotechnology letters》2012,34(12):2175-2182
The effect of T-5224, a selective inhibitor of c-Fos/activator protein (AP)-1, on lipopolysaccharide (LPS) induced liver injury was examined in mice. Administration of LPS (10?mg?kg?1, i.p.) markedly increased serum levels of tumor necrosis factor-alpha (TNFα), high mobility group box 1 (HMGB1), alanine aminotransferase/aspartate aminotransferase (ALT/AST), liver tissue levels of macrophage-inflammatory protein-1 alpha (MIP-1α) and monocyte chemoattractant protein-1 (MCP-1), as well as hepatic necrosis and inflammation, leading to 67?% lethality. Administration of T-5224 (300?mg?kg?1, p.o.) after intraperitoneal injection of LPS imparted appreciable protection against acute elevations in serum levels of TNFα, HMGB1, ALT/AST as well as in liver tissue levels of MIP-1α and MCP-1, and reduced the lethality (27?%). These data indicate that T-5224 ameliorates liver injury and improves survival through decreasing production of proinflammatory cytokines and chemokines in endotoxemic mice. 相似文献
1000.
Yu L Yamagishi J Zhang S Jin C Aboge GO Zhang H Zhang G Tanaka T Fujisaki K Nishikawa Y Xuan X 《Parasitology international》2012,61(3):481-486
A heterologous prime-boost strategy with priming plasmid DNA followed by recombinant virus expressing relevant antigens is known to stimulate protective immunity against intracellular parasites. In this study, we have evaluated a heterologous prime-boost strategy for immunizing mice against Toxoplasma gondii infection. Our results revealed that the prime-boost strategy using both plasmid DNA and adenoviral vector encoding TgAMA1 may stimulate both humoral and Th1/Th2 cellular immune responses specific for TgAMA1. Moreover, C57BL/6 mice immunized with the pAMA1/Ad5Null, pNull/Ad5AMA1, and pAMA1/Ad5AMA1 constructs showed survival rates of 12.5%, 37.5%, and 50%, respectively. In contrast, all the pNull/Ad5Null immunized mice died after infection with the PLK-GFP strain of T. gondii. Brain cyst burden was reduced by 23% in mice immunized with pAMA1/Ad5AMA1 compared with the pNull/Ad5AMA1 immunized mice. These results demonstrate that the heterologous DNA priming and recombinant adenovirus boost strategy may provide protective immunity against T. gondii infection. 相似文献