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21.
OBJECTIVE: The aim of this study was to compare the cytological changes in skin, lymph nodes, liver and bone marrow in patients with lepromatous leprosy. METHODS: Skin lesion, lymph node, liver and bone marrow aspirates were analysed. May-Grunwald-Giemsa (MGG) and Ziehl-Neelsen (Z-N) stains were employed. Comparative cytomorphology was studied. RESULTS: Twenty patients with lepromatous leprosy were studied. Lepra cells (LC) predominated in the skin aspirates of 12 patients with lepromatous leprosy (LL), lymphocytes accompanied LC in eight patients with borderline-lepromatous (BL) leprosy. Three patients of LL leprosy and two of BL leprosy in type 2 reaction additionally had numerous neutrophils. Two patterns of lymph node aspirates were seen: partial replacement with few LC in a reactive lymphoid background (10), complete replacement with either only LC or LC in a background of degenerating neutrophils (10), the latter a feature of type 2 reaction. Liver aspiration was performed in seven patients and of bone marrow in eight patients. Occasional LC were present in five liver-aspirated patients, steatosis and Kupffer cell hyperplasia in four patients, and myelopoiesis in two patients. Bone marrow smears invariably had occasional LC and a relative increase in mature plasma cells; sea-blue histiocytes were seen in six patients. CONCLUSION: Lepra cells predominated in skin and lymph node aspirates with complete replacement. In comparison, liver, bone marrow and lymph node aspirates with partial replacement were dominated by a preponderance of cells native to these organs with only few or occasional LC.  相似文献   
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Barley seeds soaked in 0.01 M sodium fluoride (NaF) in phosphate buffer (pH7) or in buffer alone for 18 h were dried and equilibrated to 10% moisture, either in air or in nitrogen. Pre-treated and re-dried seeds were irradiated in air or in nitrogen with 0, 13, 20, 26 and 32 kR of γ rays, and were immediately hydrated in oxygen- or nitrogen-bubbled water. Parameters of radiation effect considered were seedling injury, mitotic and meiotic cells with bridge aberrations at anaphase and pollen fertility in M1, and the frequency of chlorophyll mutations in M2. NaF at 0.01 M was not mutagenic by itself. Pre-treatment with NaF significantly enhanced the radiation effect, when the irradiation was done in air, in comparison with the buffer soaked seeds. The increased effect due to NaF was additional to the oxygen effect. In nitrogen, NaF pre-treatment increased the mutagenic effect but it was not always significant. Post-soaking of irradiated seeds in 0.01 M NaF for 5 h increased seedling injury in comparison with the irradiated seeds soaked in buffer alone or in 0.01 M NaCl. At least a part of the sensitizing effect of NaF may be due to the inhibition of repair.  相似文献   
24.
Two trypsin inhibitors, LA-1 and LA-2, have been isolated from ridged gourd (Luffa acutangula Linn.) seeds and purified to homogeneity by gel filtration followed by ion-exchange chromatography. The isoelectric point is atpH 4.55 for LA-1 and atpH 5.85 for LA-2. The Stokes radius of each inhibitor is 11.4 å. The fluorescence emission spectrum of each inhibitor is similar to that of the free tyrosine. The biomolecular rate constant of acrylamide quenching is 1.0×109 M?1 sec?1 for LA-1 and 0.8 × 109 M?1 sec?1 for LA-2 and that of K2HPO4 quenching is 1.6×1011 M?1 sec?1 for LA-1 and 1.2×1011M?1 sec?1 for LA-2. Analysis of the circular dichroic spectra yields 40%α-helix and 60%Β-turn for La-1 and 45%α-helix and 55%Β-turn for LA-2. Inhibitors LA-1 and LA-2 consist of 28 and 29 amino acid residues, respectively. They lack threonine, alanine, valine, and tryptophan. Both inhibitors strongly inhibit trypsin by forming enzymeinhibitor complexes at a molar ratio of unity. A chemical modification study suggests the involvement of arginine of LA-1 and lysine of LA-2 in their reactive sites. The inhibitors are very similar in their amino acid sequences, and show sequence homology with other squash family inhibitors.  相似文献   
25.
BCG has been administered globally for more than 75 years, yet tuberculosis (TB) continues to kill more than 2 million people annually. Further, BCG protects childhood TB but is quite inefficient in adults. This indicates that BCG fails to induce long-term protection. Hence there is a need to explore alternative vaccination strategies that can stimulate enduring T cell memory response. Dendritic cell based vaccination has attained extensive popularity following their success in various malignancies. In our previous study, we have established a novel and unique vaccination strategy against Mycobacterium tuberculosis (M. tb) and Salmonella typhimurium by utilizing infected macrophages (IM). In short-term experiments (30 days), substantial degree of protection was observed. However, remarkable difference was not observed in long-term studies (240 days) due to failure of the vaccine to generate long-lasting memory T cells. Hence, in the present study we employed T cell memory augmenting cytokines IL-1+IL-6+TNF-α and IL-7+IL-15 for the induction of the enhancement of long-term protection by the vaccine. We co-administered the M. tb infected macrophages vaccine with IL-1+IL-6+TNF-α (IM-1.6.α) and IL-7+IL-15 (IM-7.15). The mice were then rested for a reasonably large period (240 days) to study the bona fide T cell memory response before exposing them to aerosolized M. tb. IM-1.6.α but not IM-7.15 significantly improved memory T cell response against M. tb, as evidenced by recall responses of memory T cells, expansion of both central as well as effector memory CD4 and CD8 T cell pools, elicitation of mainly Th1 memory response, reduction in the mycobacterial load and alleviated lung pathology. Importantly, the protection induced by IM-1.6.α was significantly better than BCG. Thus, this study demonstrates that not only antigen-pulsed DCs can be successfully employed as vaccines against cancer and infectious diseases but also macrophages infected with M. tb can be utilized with great efficacy especially in protection against TB.  相似文献   
26.

Background

Long-term and unresolved airway inflammation and airway remodeling, characteristic features of chronic asthma, if not treated could lead to permanent structural changes in the airways. Aldose reductase (AR), an aldo-sugar and lipid aldehyde metabolizing enzyme, mediates allergen-induced airway inflammation in mice, but its role in the airway remodeling is not known. In the present study, we have examined the role of AR on airway remodeling using ovalbumin (OVA)-induced chronic asthma mouse model and cultured human primary airway epithelial cells (SAECs) and mouse lung fibroblasts (mLFs).

Methods

Airway remodeling in chronic asthma model was established in mice sensitized and challenged twice a week with OVA for 6 weeks. AR inhibitor, fidarestat, was administered orally in drinking water after first challenge. Inflammatory cells infiltration in the lungs and goblet cell metaplasia, airway thickening, collagen deposition and airway hyper-responsiveness (AHR) in response to increasing doses of methacholine were assessed. The TGFβ1-induced epithelial-mesenchymal transition (EMT) in SAECs and changes in mLFs were examined to investigate AR-mediated molecular mechanism(s) of airway remodeling.

Results

In the OVA-exposed mice for 6 wks inflammatory cells infiltration, levels of inflammatory cytokines and chemokines, goblet cell metaplasia, collagen deposition and AHR were significantly decreased by treatment with AR inhibitor, fidarestat. Further, inhibition of AR prevented TGFβ1-induced altered expression of E-cadherin, Vimentin, Occludin, and MMP-2 in SAECs, and alpha-smooth muscle actin and fibronectin in mLFs. Further, in SAECs, AR inhibition prevented TGFβ1- induced activation of PI3K/AKT/GSK3β pathway but not the phosphorylation of Smad2/3.

Conclusion

Our results demonstrate that allergen-induced airway remodeling is mediated by AR and its inhibition blocks the progression of remodeling via inhibiting TGFβ1-induced Smad-independent and PI3K/AKT/GSK3β-dependent pathway.  相似文献   
27.
Erratum     
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29.
Analysis of the retinal defects of a CK2 phosphomimetic variant of E(spl)M8 (M8S159D) and the truncated protein M8* encoded by the E(spl)D allele, suggest that the nonphosphorylated CtD “autoinhibits” repression. We have investigated this model by testing for inhibition (in “trans”) by the CtD fragment in its nonphosphorylated (M8‐CtD) and phosphomimetic (M8SD‐CtD) states. In N+ flies, ectopic M8‐CtD compromises lateral inhibition, i.e., elicits supernumerary bristles as with loss of N signaling. This antimorphic activity of M8‐CtD strongly rescues the reduced eye and/or bristle loss phenotypes that are elicited by ectopic M8SD or wild type M8. Additionally, the severely reduced eye of Nspl/Y; E(spl)D/+ flies is also rescued by M8‐CtD. Rescue is specific to the time and place, the morphogenetic furrow, where “founding” R8 photoreceptors are specified. In contrast, the phosphomimetic M8SD‐CtD that is predicted to be deficient for autoinhibition, exhibits significantly attenuated or negligible activity. These studies provide evidence that autoinhibition by the CtD regulates M8 activity in a phosphorylation‐dependent manner. genesis 48:44–55, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
30.
Tissue Culture Studies of Tomato (Lycopersicon esculentum)   总被引:1,自引:0,他引:1  
Tomato is a major vegetable crop that has achieved tremendous popularity over the last century. It is grown in almost every country of the world. Development of protocols for in vitro selection can provide new advances for the production of stress tolerant cultivars. Techniques have been optimised for the production of haploids and somatic hybrids. Attempts have also been made to transfer the higher regenerative ability of wild varieties to cultivated tomatoes. Although, some information is available on the morphogenesis of tomato, the techniques have not been developed to a level at which they can be utilised in large-scale multiplication of commercially important cultivars. The morphogenesis response seems to be highly dependent PGRs used in the media, which is again cultivar and genotypic specific. Somatic embryogenesis in tomato is still at its infancy, and efficient procedures for large-scale production via somatic embryogenesis are yet to be developed. Genetic stability of the tissue culture raised tomato plants also needs to be addressed. The use of a combination of molecular and conventional breeding techniques could be the option for the development of cultivars resistant to biotic and abiotic stresses. This paper reviews the advances made in various aspects of tissue culture in tomato. It also discusses the issues that still need to be addressed to utilise the full potential of plant tissue culture techniques in genetic improvement and mass propagation of tomato.  相似文献   
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