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61.
62.
Dru S. Dace Aslam A. Khan Jennifer L. Stark Jennifer Kelly Anne H. Cross Rajendra S. Apte 《PloS one》2009,4(9)
Background
Demyelinating polyneuropathy is a debilitating, poorly understood disease that can exist in acute (Guillain-Barré syndrome) or chronic forms. Interleukin-10 (IL-10), although traditionally considered an anti-inflammatory cytokine, has also been implicated in promoting abnormal angiogenesis in the eye and in the pathobiology of autoimmune diseases such as lupus and encephalomyelitis.Principal Findings
Overexpression of IL-10 in a transgenic mouse model leads to macrophage-mediated demyelinating polyneuropathy. IL-10 upregulates ICAM-1 within neural tissues, promoting massive macrophage influx, inflammation-induced demyelination, and subsequent loss of neural tissue resulting in muscle weakness and paralysis. The primary insult is to perineural myelin followed by secondary axonal loss. Infiltrating macrophages within the peripheral nerves demonstrate a highly pro-inflammatory signature. Macrophages are central players in the pathophysiology, as in vivo depletion of macrophages using clodronate liposomes reverses the phenotype, including progressive nerve loss and paralysis. Macrophage-mediate demyelination is dependent on Fas-ligand (FasL)-mediated Schwann cell death.Significance
These findings mimic the human disease chronic idiopathic demyelinating polyneuropathy (CIDP) and may also promote further understanding of the pathobiology of related conditions such as acute idiopathic demyelinating polyneuropathy (AIDP) or Guillain-Barré syndrome. 相似文献63.
Hassan Imran Afridi Tasneem Gul Kazi Farah Naz Talpur Atif Kazi Sadaf Sadia Arain Salma Aslam Arain Kapil Dev Brahman Abdul Haleem Panhwar Naeemullah 《Biological trace element research》2014,158(2):143-151
It has been speculated that trace elements may a play role in the pathogenesis of heart diseases. In the present study, we aimed to assess the levels of selenium (Se) and mercury (Hg) in biological samples (whole blood, urine, and scalp hair) of myocardial infarction (MI) patients of both genders (age range 45–60 years) at the first, second, and third heart attack (n?=?130), hospitalized in a cardiac ward of a civil hospital of Hyderabad City (Pakistan). For comparison, healthy age-matched referent subjects (n?=?61) of both genders were also selected. Se and Hg in biological samples were measured by electrothermal atomic absorption spectrometry and cold vapor atomic absorption spectrometry, prior to microwave acid digestion, respectively. The validity of the methodology was checked by biological certified reference materials. During this study, 78 % of the 32 registered patients of third MI attack (aged >50 years) died. The concentration of Se was decreased in scalp hair and blood samples of MI patients, while Hg was higher in all biological samples as compared to referent subjects. Se concentration was inversely associated with the risk of MI attacks in both genders. These results add to an increasing body of evidence that Se is a protective element for cardiovascular health. 相似文献
64.
65.
S. Bushra M. Aslam M.A. Aziz M. Ahmed 《Archives Of Phytopathology And Plant Protection》2013,46(2):205-214
This study was carried out to see the impact of Angoumois grain moth (AGM) on different cultivars of barley so that we must grow resistant variety of barley or improve those which are susceptible to it. Eggs of Sitotroga cerealella (Oliv.) were collected and reared in incubators available in Stored Product Entomology Laboratory, Pir Mehr Ali Shah Arid Agriculture University Rawalpindi, under temperature 27 ± 2°C and 60 ± 2% relative humidity. For the experiment, five different cultivars of barley; Sanober-96, Jau-83, Soorab-96, ICBA and Sterling were selected for AGM feed. After an interval of 30, 60 and 90 days of infestation, percentage damage and weight loss in grains were determined. After carrying out laboratory and field germination tests, viability of different cultivars were checked. Damage was maximum in variety Soorab (99.38%), which becomes susceptible while it was minimum in Sanober-96 (90.62%), which becomes resistant. Weight loss was maximum in variety Soorab (49.71%), which becomes susceptible and was minimum in Sanober-96 (45.32%), which becomes resistant. Damage was positively correlated with weight loss and negatively correlated with seed germination. In germination tests, on filter paper, maximum germination was found in variety Sterling (3%) which becomes resistant and it was minimum in ICBA which becomes susceptible (0%). In sand germination test, maximum seeds germinated in variety Sanober-96 (2%), and minimum seeds germinated in ICBA (0%). By calculating the percentage of losses of different cultivars, it was found that none of cultivars proved itself completely resistant or susceptible. 相似文献
66.
Poly(o-anisidine) molybdophosphate was expediently obtained by sol-gel mixing of Poly(o-anisidine) into the inorganic matrices of molybdophosphate, which was allowed to react with silver nitrate to the formation of poly(o-anisidine) molybdophosphate embedded silver nano composite. The composite was characterized by Fourier Transform Infrared Spectroscopy, X-ray powder diffraction, UV-Vis Spectrophotometry, Fluorescence Spectroscopy, Scanning Electron Microscopy/Energy-dispersive X-ray Spectroscopy and Thermogravimertic Analysis. Ion exchange capacity and distribution studies were carried out to understand the ion-exchange capabilities of the nano composite. On the basis of highest distribution studies, this nano composite cation exchanger was used as preparation of heavy metal ion selective membrane. Membrane was characterized for its performance as porosity and swelling later on was used for the preparation of membrane electrode for Hg(II), having better linear range, wide working pH range (2–4.5) with fast response in the real environment. 相似文献
67.
Vinores SA Xiao WH Aslam S Shen J Oshima Y Nambu H Liu H Carmeliet P Campochiaro PA 《Journal of cellular physiology》2006,206(3):749-758
Retinal neovascularization (NV) and macular edema, resulting from blood-retinal barrier (BRB) breakdown, are major causes of visual loss in ischemic retinopathies. Choroidal NV (CNV) occurs in diseases of the retinal pigmented epithelium/Bruch's membrane complex and is another extremely prevalent cause of visual loss. We used mice in which the hypoxia response element (HRE) is deleted from the vascular endothelial growth factor (vegf) promoter (Vegf(delta/delta) mice) to explore the role of induction of VEGF through the HRE in these disease processes. Compared to wild type (Vegf+/+) mice with oxygen-induced ischemic retinopathy (OIR) in which vegf mRNA levels were increased and prominent retinal NV and BRB breakdown occurred, Vegf(delta/delta) littermates with OIR failed to increase vegf mRNA levels in the retina and had significantly less retinal NV and BRB breakdown, but showed prominent dilation of some superficial retinal vessels. Vegf(+/delta) littermates with ischemic retinopathy developed comparable retinal NV to Vegf+/+ mice, exhibited intermediate levels of BRB breakdown, and did not show vasodilation. In a mouse model of CNV, due to laser-induced rupture of Bruch's membrane, the area of CNV at Bruch's membrane rupture sites was more than tenfold greater in Vegf+/+ mice than in Vegf(delta/delta) littermates. In contrast to these dramatic differences in pathologic ocular NV, Vegf(delta/delta) mice showed subtle differences in retinal vascular development compared to Vegf+/+ mice; it was slightly delayed, but otherwise normal. These data suggest that induction of VEGF through the HRE in its promoter is critical for retinal and CNV, but not for retinal vascular development. 相似文献
68.
Shazmeen Aslam Irfan Khan Fatima Jameel Midhat Batool Zaidi Asmat Salim 《World journal of stem cells》2020,12(12):1652-1666
BACKGROUNDImpaired wound healing can be associated with different pathological states. Burn wounds are the most common and detrimental injuries and remain a major health issue worldwide. Mesenchymal stem cells (MSCs) possess the ability to regenerate tissues by secreting factors involved in promoting cell migration, proliferation and differentiation, while suppressing immune reactions. Preconditioning of MSCs with small molecules having cytoprotective properties can enhance the potential of these cells for their use in cell-based therapeutics.AIMTo enhance the therapeutic potential of MSCs by preconditioning them with isorhamnetin for second degree burn wounds in rats.METHODSHuman umbilical cord MSCs (hU-MSCs) were isolated and characterized by surface markers, CD105, vimentin and CD90. For preconditioning, hU-MSCs were treated with isorhamnetin after selection of the optimized concentration (5 µmol/L) by cytotoxicity analysis. The migration potential of these MSCs was analyzed by the in vitro scratch assay. The healing potential of normal, and preconditioned hU-MSCs was compared by transplanting these MSCs in a rat model of a second degree burn wound. Normal, and preconditioned MSCs (IH + MSCs) were transplanted after 72 h of burn injury and observed for 2 wk. Histological and gene expression analyses were performed on day 7 and 14 after cell transplantation to determine complete wound healing.RESULTSThe scratch assay analysis showed a significant reduction in the scratch area in the case of IH + MSCs compared to the normal untreated MSCs at 24 h, while complete closure of the scratch area was observed at 48 h. Histological analysis showed reduced inflammation, completely remodeled epidermis and dermis without scar formation and regeneration of hair follicles in the group that received IH + MSCs. Gene expression analysis was time dependent and more pronounced in the case of IH + MSCs. Interleukin (IL)-1β, IL-6 and Bcl-2 associated X genes showed significant downregulation, while transforming growth factor β, vascular endothelial growth factor, Bcl-2 and matrix metallopeptidase 9 showed significant upregulation compared to the burn wound, showing increased angiogenesis and reduced inflammation and apoptosis.CONCLUSIONPreconditioning of hU-MSCs with isorhamnetin decreases wound progression by reducing inflammation, and improving tissue architecture and wound healing. The study outcome is expected to lead to an improved cell-based therapeutic approach for burn wounds. 相似文献
69.
Differential effect of ammonium on the induction of nitrate and nitrite reductase activities in roots of barley (Hordeum vulgare) seedlings 总被引:2,自引:0,他引:2
Muhammad Aslam Robert L. Travis D. William Rains Ray C. Huffaker 《Physiologia plantarum》1997,101(3):612-619
The effect of exogenous NH4+ on the induction of nitrate reductase activity (NRA; EC 1.6.6.1) and nitrite reductase activity (NiRA; EC 1.7.7.1) in roots of 8-day-old intact barley (Hordeum vulgare L.) seedlings was studied. Enzyme activities were induced with 0.1, 1 or 10 mM NO3+ in the presence of 0, 1 or 10 mM NH4+, Exogenous NH4+ partially inhibited the induction of NRA when roots were exposed to 0.1 mM, but not to 1 or 10 mM NO3+, In contrast, the induction of NiRA was inhibited by NH4+ at all NO3+ levels. Maximum inhibition of the enzyme activities occurred at 1.0 mM NH4+ Pre-treatment with NH4+ had no effect on the subsequent induction of NRA in the absence of additional NH4+ whereas the induction of NiRA in NH4+-pretreated roots was inhibited in the absence of NH4+ At 10 mM NO3+ L-methionine sulfoximine stimulated the induction of NRA whether or not exogenous NH4+ was present. In contrast, the induction of NiRA was inhibited by L-methionine sulfoximine irrespective of NH4+ supply. During the postinduction phase, exogenous NH4+ decreased NRA in roots supplied with 0.1 mM but not with 1mM NH3+ whereas, NiRA was unaffected by NH4+ at either substrate concentration. The results indicate that exogenous NH4+ regulates the induction of NRA in roots by limiting the availability of NO3+. Conversely, it has a direct effect, independent of the availability of NO3+, on the induction of NiRA. The lack of an NH4+ effect on NiRA during the postinduction phase is apparently due to a slower turnover rate of that enzyme. 相似文献
70.
Munir Ozturk Mert Metin Volkan Altay Tomonori Kawano Alvina Gul Bengu Turkyilmaz Unal Dilek Unal Rouf Ahmad Bhat Moonisa Aslam Dervash Kristina Toderich Esra Koc Pedro Garcia Caparros leeb Shahzadi 《Phyton》2023,92(1):165-192
Aluminum is an abundant metal in the earth’s crust that turns out to be toxic in acidic environments. Many plants are affected by the presence of aluminum at the whole plant level, at the organ level, and at the cellular level. Tobacco as a cash crop (Nicotiana tabacum L.) is a widely cultivated plant worldwide and is also a good model organism for research. Although there are many articles on Al-phytotoxicity in the literature, reviews on a single species that are economically and scientifically important are limited. In this article, we not only provide the biology associated with tobacco Al-toxicity, but also some essential information regarding the effects of this metal on other plant species (even animals). This review provides information on aluminum localization and uptake process by different staining techniques, as well as the effects of its toxicity at different compartment levels and the physiological consequences derived from them. In addition, molecular studies in recent years have reported specific responses to Al toxicity, such as overexpression of various protective proteins. Besides, this review discusses data on various organelle-based responses, cell death, and other mechanisms, data on tobacco plants and other kingdoms relevant to these studies. 相似文献