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81.

Background

In a previous randomized controlled trial, we found that sitting isometric yoga improves fatigue in patients with chronic fatigue syndrome (CFS) who are resistant to conventional therapy. The aim of this study was to investigate possible mechanisms behind this finding, focusing on the short-term fatigue-relieving effect, by comparing autonomic nervous function and blood biomarkers before and after a session of isometric yoga.

Methods

Fifteen patients with CFS who remained symptomatic despite at least 6 months of conventional therapy practiced sitting isometric yoga (biweekly 20 min practice with a yoga instructor and daily home practice) for eight weeks. Acute effects of sitting isometric yoga on fatigue, autonomic function, and blood biomarkers were investigated after the final session with an instructor. The effect of a single session of sitting isometric yoga on fatigue was assessed by the Profile of Mood Status (POMS) questionnaire immediately before and after the session. Autonomic nervous function (heart rate (HR) variability) and blood biomarkers (cortisol, DHEA-S, TNF-α, IL-6, IFN-γ, IFN-α, prolactin, carnitine, TGF-β1, BDNF, MHPG, and HVA) were compared before and after the session.

Results

Sitting isometric yoga significantly reduced the POMS fatigue score (p?<?0.01) and increased the vigor score (p?<?0.01). It also reduced HR (p?<?0.05) and increased the high frequency power (p?<?0.05) of HR variability. Sitting isometric yoga increased serum levels of DHEA-S (p?<?0.05), reduced levels of cortisol (p?<?0.05) and TNF-α (p?<?0.05), and had a tendency to reduce serum levels of prolactin (p?<?0.1). Decreases in fatigue scores correlated with changes in plasma levels of TGF-β1 and BDNF. In contrast, increased vigor positively correlated with HVA.

Conclusions

A single session of sitting isometric yoga reduced fatigue and increased vigor in patients with CFS. Yoga also increased vagal nerve function and changed blood biomarkers in a pattern that suggested anti-stress and anti-inflammatory effects. These changes appear to be related to the short-term fatigue-relieving effect of sitting isometric yoga in patients with CFS. Furthermore, dopaminergic nervous system activation might account for sitting isometric yoga-induced increases in energy in this patient population.

Trial registration

University Hospital Medical Information Network (UMIN CTR) UMIN000009646. Registered Dec 27, 2012.
  相似文献   
82.
In potato tuber tissue, treatment of fungal elicitor, hyphalwall components (HWC) induces various plant defense reactions.As treatment of protein kinase inhibitor prior to HWC treatmentblocks some of defense reactions induced by HWC, involvementof protein kinases in plant defense induction is proposed. Here,we demonstrate HWC-induced activation of a 51-kDa protein kinase(abbreviated p51-PK) using myelin basic protein as a substratein potato tuber discs. The activity of p51-PK was not detectedin the absence of phosphatase inhibitor, NaF, and p51-PK wasimmuroprecipitated with antibody against phosphotyrosine. Pretreatmentof phospholipase C inhibitor, neomycin, and GTP-binding proteinactivator, mastoparan, partially inhibited the HWC-induced activationof p51-PK, suggesting possible involvement of phospholipaseC and GTP-binding protein in the activation of p51-PK. Exogenouslysupplied elicitors, salicylic acid and arachidonic acid, whichare known to induce various defense responses in potato plants,also activated the protein kinase showing the same migrationas p51-PK on SDS-PAGE and different activation patterns. Theseresults implied that p51-PK might be involved in several signaltransduction pathways leading to plant defense responses initiatedby different stimuli. (Received January 11, 1999; Accepted May 25, 1999)  相似文献   
83.
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85.
Humanin and calmodulin‐like skin protein (CLSP) inhibits Alzheimer disease (AD)‐related neuronal cell death via the heterotrimeric humanin receptor in vitro . It has been suggested that CLSP is a central agonist of the heterotrimeric humanin receptor in vivo . To investigate the role of CLSP in the AD pathogenesis in vivo , we generated mouse CLSP‐1 transgenic mice, crossed them with the APPswe/PSEN1dE9 mice, a model mouse of AD, and examined the effect of CLSP over‐expression on the pathological phenotype of the AD mouse model. We found that over‐expression of the mouse CLSP‐1 gene attenuated spatial learning impairment, the loss of a presynaptic marker synaptophysin, and the inactivation of STAT3 in the APPswe/PSEN1dE9 mice. On the other hand, CLSP over‐expression did not affect levels of Aβ, soluble Aβ oligomers, or gliosis. These results suggest that the CLSP‐mediated attenuation of memory impairment and synaptic loss occurs in an Aβ‐independent manner. The results of this study may serve as a hint to the better understanding of the AD pathogenesis and the development of AD therapy.

  相似文献   
86.
We investigated the effect of the number of oxyethylene groups (polymer molecular weight) and the interchain binding and/or entanglements of methoxy-terminated-poly(ethylene glycol) (m-PEG) brushes on their ability to adsorb to living malignant melanoma B16F10 cells. We used the atomic force microscope colloid probe method to determine the adhering ability of the m-PEG brushes to the cells, as the magnitude of the adhesion force between the m-PEG modified particles and the living cells in a physiological buffer was related to the binding strength of the m-PEGs to the cells. We saw that m-PEG brushes (average molecular weights 330, 1900, and 5000 g/mol), which were chemically attached to silica particles, may bind to living B16F10 cells. The binding of m-PEGs to living B16F10 cells increased as the oxyethylene chain length of the m-PEGs increased, if the m-PEGs had a low degree of entanglements or little inter-m-PEG chain binding. A high degree of entanglements or interchain binding decreased the ability of an m-PEG chain to bind to a living cell. The effect of m-PEG (molecular weight 1900 g/mol) being present at cell surfaces for 24 h was also seen not to induce the death of the cells or affect their growth.  相似文献   
87.
The ecological advantage of diel vertical migration on the nutrition and accumulation of Chattonella antiqua, which is one of the dominant red-tide forming phytoplankton species in the Seto Inland Sea of Japan, was examined using a large axenic culture tank, in which vertical stratification of salinity, temperature and nutrients was maintained, analogous to natural conditions observed when red tides occur. C. antiqua was capable of migrating through very sharp salinity and temperature gradients. At night the species migrated to the deep nutrient-rich water and assimilated nutrients. During the daytime it migrated to the nutrient-depleted surface water and used the accumulated nutrients for photosynthesis. Nitrogen uptake was synchronized with phosphate uptake. 31P-NMR spectroscopy during the migration experiment revealed that C. antiqua has the capability of nocturnal phosphate uptake in the deep nutrient-rich water, but no capability of synthesizing polyphosphate, which was considered to be the intracellular phosphate pool. These findings were compared with those reported for another raphidophycean, Heterosigma akashiwo. Although both species carry out vertical migration and nocturnal nutrient uptake, only H. akashiwo has the capability of making an intracellular polyphosphate pool. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
88.
Hayashi K  Sudo Y  Jee J  Mishima M  Hara H  Kamo N  Kojima C 《Biochemistry》2007,46(50):14380-14390
Halobacterial pharaonis phoborhodopsin [ppR, also called Natronomonas pharaonis sensory rhodopsin II (NpSRII)] is a phototaxis protein which transmits a light signal to the cytoplasm through its transducer protein (pHtrII). pHtrII, a two-transmembrane protein that interacts with ppR, belongs to the group of methyl-accepting chemotaxis proteins (MCPs). Several mutation studies have indicated that the linker region connecting the transmembrane and methylation regions is necessary for signal transduction. However, the three-dimensional (3D) structure of an MCP linker region has yet to be reported, and hence, details concerning the signal transduction mechanism remain unknown. Here the structure of the pHtrII linker region was investigated biochemically and biophysically. Following limited proteolysis, only one trypsin resistant fragment in the pHtrII linker region was identified. This fragment forms a homodimer with a Kd value of 115 microM. The 3D structure of this fragment was determined by solution NMR, and only one alpha-helix was found between two HAMP domains of the linker region. This alpha-helix was significantly stabilized within transmembrane protein pHtrII as revealed by CW-EPR. The presence of Af1503 HAMP domain-like structures in the linker region was supported by CD, NMR, and ELDOR data. The alpha-helix determined here presumably works as a mechanical joint between two HAMP domains in the linker region to transfer the photoactivated conformational change downstream.  相似文献   
89.
Sensory rhodopsin II (SRII, also called pharaonis phoborhodopsin, ppR) is responsible for negative phototaxis in Natronomonas pharaonis. Photoisomerization of the retinal chromophore from all- trans to 13- cis initiates conformational changes in the protein, leading to activation of the cognate transducer protein (HtrII). We previously observed enhancement of the C 14-D stretching vibration of the retinal chromophore at 2244 cm (-1) upon formation of the K state and interpreted that a steric constraint occurs at the C 14D group in SRII K. Here, we identify the counterpart of the C 14D group as Thr204, because the C 14-D stretching signal disappeared in T204A, T204S, and T204C mutants as well as a C 14-HOOP (hydrogen out-of-plane) vibration at 864 cm (-1). Although the K state of the wild-type bacteriorhodopsin (BR), a light-driven proton pump, possesses neither 2244 nor 864 cm (-1) bands, both signals appeared for the K state of a triple mutant of BR that functions as a light sensor (P200T/V210Y/A215T). We found a positive correlation between these vibrational amplitudes of the C 14 atom at 77 K and the physiological phototaxis response. These observations strongly suggest that the steric constraint between the C 14 group of retinal and Thr204 of the protein is a prerequisite for light-signal transduction by SRII.  相似文献   
90.
The renal renin-angiotensin system plays a central role in the development of hypertension. The aim of this work was to verify the expression of angiotensin II receptors AT(1)R and AT(2)R in the microsomal fraction of renal cortex and correlate this with the development of hypertension and renal damage in spontaneously hypertensive rats (SHR) using Wistar-Kyoto rats (WKY) as controls. AT(1)R expression increased (126%) and AT(2)R expression decreased (66%) in 4-wk-old SHR; AT(2) expression decreased in 14-wk-old SHR (61%) compared with respective age-matched WKY. These modifications were correlated to the increase in protein kinase C activity and decrease in protein kinase A activity. Four-week-old SHR showed large accumulations of macrophages in kidney glomerulus and the tubulointerstitial area, dense cortical collagen deposition, and arterial proliferative changes in the walls of arterioles and medium-sized vessels. Similar modifications were also observed in 14-wk-old SHR. Four-week-old SHR treated with losartan (30 mg·kg(-1)·day(-1)) or hydralazine (15 and 30 mg·kg(-1)·day(-1)) by gavage for 10 wk did not develop hypertension. The decrease in AT(2)R expression and renal damage observed in SHR remained even after treatment with hydralazine. On the other hand, losartan treatment prevented the modifications observed in 14-wk-old SHR, indicating that renal injuries are caused specifically by AT(1) rather than an increase in blood pressure. Our results indicate that the imbalance in AT(1)R and AT(2)R expression is associated with an inflammatory process that contributes to renal injury in adult SHR and to the development of hypertension.  相似文献   
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