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991.
Methicillin-resistant Staphylococcus spp. (MRSS) are causing numerous forms of illness in humans ranging from mild to fatal infections. We need to investigate the resistant pattern for different clinical isolates to control the resistance phenomena. This study was designed to provide the resistance pattern of isolated Staphylococcus spp. from various clinical samples in Khartoum State and to elucidate the frequencies of Multidrug-resistant (MDR), Extensively drug-resistant (XDR) and pan-drug resistant (PDR). Two hundred and ten bacterial isolates were from different sources (catheter tip, sputum, vaginal swab, urine, tracheal aspirate, blood, pus, nasal swab, stool, throat swab, pleural fluid, and ear swab). Isolates were identified based on their morphological characters and biochemical reaction. Antibiotics susceptibility screening was performed using twenty-three antibiotics from eighteen classes against all isolated Staphylococcus spp. following the Clinical and Laboratory Standards Institute (CLSI) guideline. The result revealed that out of 63 Gram-positive isolated bacteria, 52 (82.5%) were Staphylococcus spp. with a high incidence of S. aureus 37(71.2%). Out of all Staphylococcus spp., 38 (73.1%) were Methicillin-resistant (MR). The prevalence of MDR was higher in S. aureus (89.2%) than in S. epidermidis (75%). All Staphylococcus spp. displayed resistance to ampicillin and penicillin, while all S. aureus were sensitive to daptomycin and fosfomycin. One isolate was XDR possible PDR, while no PDR was reported in all isolated bacteria. This study provided evidence for the antimicrobial-resistant (AMR) burden in Sudan and highlighted the need for a practical and functional stewardship program to reduce the unreasonable costs of antibiotics.  相似文献   
992.
The main objective of the present study was to evaluate the influence of encapsulation by extrusion technique using two hydrogels, namely; sodium alginate (Na-ALG) and whey protein isolate (WPI) on Bifidobacterium bifidium viability and stability of yoghurt under simulated gastrointestinal conditions. Probiotic bacteria (free or encapsulated) were added to yogurt for four weeks to test their viability and stability. Physicochemical and sensory analysis of yoghurt were conducted. Viability of B. bifidium in the simulated gastrointestinal conditions pH 2 and pH 7.5 was determined. Also, the efficiency of encapsulated final yield of the microcapsules was determined. With storage time, the pH of yoghurt containing encapsulated bacteria increased more than that of yoghurt containing free probiotic bacteria, resulting in a decrease in acidity. When compared to yoghurt containing encapsulated bacteria, the lactose level of yoghurt containing free probiotic bacteria decreased over time. The viscosity of yoghurt containing encapsulated WPI remained stable over the storage period, with syneresis remaining stable. The sensory properties of yoghurt containing free probiotics deteriorated over time. Cell viability was significantly reduced in yoghurt-containing free probiotics compared to other treated yoghurts. Cell viability in free probiotics yoghurt was lower than in encapsulated ones when exposed to simulated gastric and intestinal juice. In conclusion, WPI- encapsulated probiotics showed better stability over 28 days of storage in both yoghurt and gastrointestinal conditions, followed by sodium alginate.  相似文献   
993.
Microfibril-associated glycoprotein (MAGP) 1 and 2 are evolutionarily related but structurally divergent proteins that are components of microfibrils of the extracellular matrix. Using mice with a targeted inactivation of Mfap5, the gene for MAGP2 protein, we demonstrate that MAGPs have shared as well as unique functions in vivo. Mfap5−/− mice appear grossly normal, are fertile, and have no reduction in life span. Cardiopulmonary development is typical. The animals are normotensive and have vascular compliance comparable with age-matched wild-type mice, which is indicative of normal, functional elastic fibers. Loss of MAGP2 alone does not significantly alter bone mass or architecture, and loss of MAGP2 in tandem with loss of MAGP1 does not exacerbate MAGP1-dependent osteopenia. MAGP2-deficient mice are neutropenic, which contrasts with monocytopenia described in MAGP1-deficient animals. This suggests that MAGP1 and MAGP2 have discrete functions in hematopoiesis. In the cardiovascular system, MAGP1;MAGP2 double knockout mice (Mfap2−/−;Mfap5−/−) show age-dependent aortic dilation. These findings indicate that MAGPs have shared primary functions in maintaining large vessel integrity. In solid phase binding assays, MAGP2 binds active TGFβ1, TGFβ2, and BMP2. Together, these data demonstrate that loss of MAGP2 expression in vivo has pleiotropic effects potentially related to the ability of MAGP2 to regulate growth factors or participate in cell signaling.  相似文献   
994.
Molecular genetic methods can distinguish divergent evolutionary lineages in what previously appeared to be single species, but it is not always clear what functional differences exist between such cryptic species. We used a metabolomic approach to profile biochemical phenotype (metabotype) differences between two putative cryptic species of the earthworm Lumbricus rubellus. There were no straightforward metabolite biomarkers of lineage, i.e. no metabolites that were always at higher concentration in one lineage. Multivariate methods, however, identified a small number of metabolites that together helped distinguish the lineages, including uncommon metabolites such as Nε-trimethyllysine, which is not usually found at high concentrations. This approach could be useful for characterizing functional trait differences, especially as it is applicable to essentially any species group, irrespective of its genome sequencing status.  相似文献   
995.
Dobutamine is a β-adrenergic agonist with an affinity higher for receptor expressed in the heart (β1) than for receptors expressed in the arteries (β2). When systemically administered, it increases cardiac demand. Thus, dobutamine unmasks abnormal rhythm or ischemic areas potentially at risk of infarction. Monitoring of heart function during a cardiac stress test can be performed by either ecocardiography or cardiac catheterization. The latter is an invasive but more accurate and informative technique that the former.Cardiac stress test induced by dobutamine and monitored by cardiac catheterization accomplished as described here allows, in a single experiment, the measurement of the following hemodynamic parameters: heart rate (HR), systolic pressure, diastolic pressure, end-diastolic pressure, maximal positive pressure development (dP/dtmax) and maximal negative pressure development (dP/dtmin), at baseline conditions and under increasing doses of dobutamine.As expected, in normal mice we observed a dobutamine dose-related increase in HR, dP/dtmax and dP/dtmin. Moreover, at the highest dose tested (12 ng/g/min) the cardiac decompensation of high fat diet-induced obese mice was unmasked.  相似文献   
996.
Examining molecular mechanisms involved in neuropathological conditions, such as ischemic stroke, can be difficult when using whole animal systems. As such, primary or ''neuronal-like'' cell culture systems are commonly utilized. While these systems are relatively easy to work with, and are useful model systems in which various functional outcomes (such as cell death) can be readily quantified, the examined outcomes and pathways in cultured immature neurons (such as excitotoxicity-mediated cell death pathways) are not necessarily the same as those observed in mature brain, or in intact tissue. Therefore, there is the need to develop models in which cellular mechanisms in mature neural tissue can be examined. We have developed an in vitro technique that can be used to investigate a variety of molecular pathways in intact nervous tissue. The technique described herein utilizes rat cortical tissue, but this technique can be adapted to use tissue from a variety of species (such as mouse, rabbit, guinea pig, and chicken) or brain regions (for example, hippocampus, striatum, etc.). Additionally, a variety of stimulations/treatments can be used (for example, excitotoxic, administration of inhibitors, etc.). In conclusion, the brain slice model described herein can be used to examine a variety of molecular mechanisms involved in excitotoxicity-mediated brain injury.  相似文献   
997.
Robert Perger  Adam Wall 《ZooKeys》2014,(435):93-109
In this contribution a new species of the land crab genus Gecarcinus Leach, 1814, from the Neotropical Pacific coast of South America is described and illustrated. In addition to its unique body color, Gecarcinus nobilii sp. n. is distinguished from congeners by a distinctly wider carapace front and differences in the shape of the infraorbital margin. The new species is not isolated from Gecarcinus populations from the Pacific coast of Central America by an insurmountable geographic barrier. Considering the closure of the Panamanian Isthmus as a calibration point for morphological divergence between the trans-isthmian mainland populations of Gecarcinus, the virtual lack of morphological differentiation (other than color) between them and the distinctness of G. nobilii sp. n. suggests that G. nobilii sp. n. evolved from a common ancestor before the Isthmus closed.  相似文献   
998.
Abstract

The thermodynamic model of inorganic arsenic (acid–base, complexation, precipitation and redox equilibria) was validated with results obtained in arsenic mobilisation processes taking place in several river sediment samples of the Basque Country (North of Spain). Natural waters in contact with the sediment were collected at each sampling point, together with the sediment samples. These waters were analysed and then used as the extractant in the mobilisation studies. Considering pH, redox potential and total concentration values of the main cations and anions, the stoichiometric equilibrium constant were computed for each river water situation. The activity coefficient values of the inorganic arsenic species were estimated by means of the Modified Bromley Methodology (MBM). Both water and sediment for each sampling site were used in the mobility experiments, and the results were compared with the theoretical predictions of the thermodynamic model extrapolated to the chemical conditions of the sampling point. Moreover, a correlation analysis was also performed taking into account all the data and sampling sites; these results were also discussed and compared with the theoretical speciation obtained from the basic model of inorganic arsenic.  相似文献   
999.
In the present study we have evaluated the antigenotoxic effects of Farnesol (FL) a 15-carbon isoprenoid alcohol against benzo (a) pyrene [B(a)P] (125 mg kg? 1.b.wt oral) induced toxicity. B(a)P administration lead to significant induction in Cytochrome P450 (CYP) content and aryl hydrocarbon hydrolase (AHH) activity (p < 0.001), DNA strand breaks and DNA adducts (p < 0.001) formation. FL was shown to suppress the activities of both CYP and AHH (p < 0.005) in modulator groups. FL pretreatment significantly (p < 0.001) restored depleted levels of reduced glutathione (GSH), quinone reductase (QR) and glutathione –S-transferase (GST). A simultaneous significant and at both the doses reduction was seen in DNA strand breaks and in in-vivo DNA adducts formation (p < 0.005), which gives some insight on restoration of DNA integrity. The results support the protective nature of FL. Hence present data supports FL as a future drug to preclude B (a) P induced toxicity.  相似文献   
1000.
范小利  罗涛  张雪葳  吴良龙 《生态学报》2022,42(8):3155-3166
居住建筑能耗受建筑周边空间形态的直接影响,确定空间形态低碳效应及其最佳尺度将有助于实现县域城镇低碳转型。以浙江省长兴县、福建省连江县为例,共计选取49个具有代表性的居住建筑样本,采用GIS分析与数理统计相结合的方式,在居住建筑1800m半径范围内,以200m为间隔建立缓冲区,开展全年、最冷月份能耗期及最热月份能耗期建筑能耗与周边空间形态关联性的连续尺度研究。结果表明:(1)道路密度、开发密度、容积率均与建筑能耗呈正相关,但各指标对应的能耗时期、尺度范围有较大差异。(2)水面率、土地利用混合度是与建筑能耗相关的共性指标,但在不同地区的正负效应及尺度范围不同;(3)影响浙闽地区县域城镇最热月份能耗期能耗的关键形态因子为1000m-道路密度、800m-水面率、1600m-开放空间率;影响连江最冷月份能耗期能耗的关键形态因子为800m-水面率。(4)就控碳单元设置而言,长兴县可重点关注1000—1200m半径范围,连江县可重点关注800—1000m、1400m半径范围。(5)浙闽地区县域城镇特性指标为开放空间率,与最热月份能耗期建筑能呈负相关;长兴县特性指标为容积率、水岸密度,分别与全年、最冷...  相似文献   
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