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81.
Predation is one of the key factors shaping the dynamics of animal populations. In birds, nest loss due to predation can be a significant cause of low reproductive success. Ground-nesting birds are among the bird groups most susceptible to predation, mainly because their nests are easily accessible to a broad suite of potential predators. For these birds, anthropogenic disturbances can generate changes in nest predation risk by altering their antipredator behaviour and also by altering the behaviour of the predator species, i.e. the predator becoming much more aware of predation opportunities due to frequent disturbances and/or motivated to repeat predation attempts when some are successful. To date, most previous studies investigating this have focused on a single effect, either predation or disturbance, on chick survival. It remains unknown how the risk of predation with and without disturbance varies with chick age. In this study, we used behavioural observations to assess how the interaction between predators and disturbance affects predation risk in chicks and how this interacts with chick age. Specifically, we investigated the effect of disturbance caused by humans and stray dogs on the predation of Slender-billed Gull Chroicocephalus genei chicks by Yellow-legged Gulls Larus michahellis, and whether this depended on the age of the chicks. Our results revealed that disturbance had a significant positive effect on predation measures of Slender-billed Gull chicks by Yellow-legged Gulls, but that this effect was mediated both by disturbance type and the age of chicks. Stray dogs entering the colony had a stronger disturbance effect on chicks than passing humans, increasing predation risk by Yellow-legged Gulls. Our results also showed that chick age interacts with disturbance type to determine the predation risk. This is probably mediated by chicks' capacity to escape predation by gathering in a single large crèche that runs into the water when disturbed. To preserve Slender-billed Gull colonies in one of its few remaining breeding sites in Tunisia, and as gulls tend to react even when the disturbance occurs relatively far from the colonies, it is crucial to (1) restrict human access to dikes and islets where large colonies breed and (2) construct artificial islets attractive to gulls and inaccessible to stray dogs.  相似文献   
82.
The present work aimed to study in rats whether substitution of a low level of fish oil (FO; 2.2% of calories) into a low-fat diet (6.6% of calories from fat as peanut-rape oil or control diet) 1) has a tissue-specific effect on insulin signaling pathway and 2) prevents dexamethasone-induced alteration of insulin signaling in liver, muscle, and adipose tissue. Sixteen rats were used for study of insulin signaling, and sixteen rats received an oral glucose load (3 g/kg). Eight rats/group consumed control diet or diet containing FO over 5 wk. Four rats from each group received a daily intraperitoneal injection of saline or dexamethasone (1 mg.kg(-1).day(-1)) for the last 5 days of feeding. In liver, FO decreased phosphatidylinositol 3'-kinase (PI 3'-kinase) activity by 54% compared with control diet. A similar result was obtained in muscle. In both liver and muscle, FO clearly amplified the effect of dexamethasone. FO did not alter early steps of insulin signaling, and in muscle GLUT4 protein content remained unaltered. In adipose tissue, FO increased PI 3'-kinase activity by 74%, whereas dexamethasone decreased it by 65%; inhibition of PI 3'-kinase activity by dexamethasone was similar in rats fed FO or control diet, and GLUT4 protein content was increased by 61% by FO. Glycemic and insulinemic responses to oral glucose were not modified by FO. In conclusion, FO increased PI 3'-kinase activity in adipose tissue while inhibiting it in liver and muscle. The maintenance of whole body glucose homeostasis suggests an important role of adipose tissue for control of glucose homeostasis.  相似文献   
83.
A series of trisubstituted indolizine analogues has been designed as a result of a fragment-based approach to target the inhibition of mycobacterial enoyl-acyl carrier protein reductase. Anti-tuberculosis (TB) screening of the characterized compounds by a resazurin microplate assay method revealed that ethyl group at second position of indolizine nucleus exhibited activity against susceptible and multidrug-resistant strains of Mycobacterium tuberculosis at concentration of 5.5 and 11.3 μg/mL, respectively. A molecular docking study was also conducted to evaluate the stability of the active compounds, and compound with ethyl substitution at second position of indolizine nucleus showed the highest free binding energy of ΔG ?24.11 (kcal/mol), a low clash score of 3.04, and high lipo score of ?13.33. Indolizine analog with ethyl substitution at second position demonstrated Molecular Mechanics/Generalized Born Surface Area (?23.85 kcal/mol). Two molecular dynamics studies were computed (100 ps and 50 ns) to calculate the relationship between the potential and kinetic energies of the active anti-TB compound with time and temperature. The discovery of this lead may have a positive impact on anti-TB drug discovery.  相似文献   
84.
85.
Molecular Biology Reports - Introns experience lesser selection pressure, thus are liable for higher polymorphism. Intron Length Polymorphic (ILP) markers designed from exon-flanking introns...  相似文献   
86.

MicroRNAs (miRNAs) play important roles in liver pathologies and they are potential biomarkers for diagnosis of liver diseases progression. Changes in miRNA sera expression can be used as non-invasive biomarkers for hepatocellular carcinoma (HCC). The aim of the study was to identify the miRNome profiling of HCC and its diagnostic value in distinguishing HCC from healthy individuals. Expression profiles of miRNAs in serum samples of 20 HCC patients and 10 healthy controls were detected. Whole miRNome profiling was done using next generation sequencing. Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic performance of the deregulated miRNAs for discriminating HCC cases from healthy controls. MiRNA 142 was highly expressed in HCC (P value?=?0.023) while miRNAs 191, 22, and 126 were higher in the controls (P value?=?0.005, 0.034, 0.010 respectively). We have identified 5 novel miRNAs and they were highly expressed in HCC than controls. Analysis of ROC curve demonstrated that these deregulated miRNAs can be used as a reliable biomarker for detection of HCC with high diagnostic accuracy (AUC?=?0.93). We have detected a panel of serum miRNAs that can be used as a reliable noninvasive screening biomarker of HCC. The study recommends further research to shed light on a possible role of the newly discovered novel miRNAs in HCC pathogenesis.

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87.
Introgression of spontaneous or induced mutations has been used to increase the levels and diversify the profile of antioxidants in many fruits including tomato. The high-pigment (hp) and old-gold (og) alleles exemplify this approach as attractive genetic resources suitable to inbred elite high-lycopene (HLY) tomato lines with improved color and nutritional attributes. Although several studies have been published on HLY tomatoes, a systematic analysis of the information on their agronomic performances, processing features, and functional quality is lacking, leaving room for the assumption of their poor competitiveness with conventional tomato cultivars and limiting their agricultural diffusion. Therefore, the aim of this study is to critically review the most important agronomic, horticultural, and functional traits of HLY tomatoes, as well as the advances in some emerging (pre)industrial applications. Field experiments performed in different countries showed that most available HLY lines are productive, vigorous, with excellent foliage cover and with morphologically acceptable fruit. Tomato yield of HLY genotypes ranged from ~30 to ~178 t/ha exceeding, in some trials, that of highly productive cultivars. Red-ripe fruits of most HLY lines showed commercially suitable soluble solids and titratable acidity, in addition to increased levels of lycopene (up to 440 mg/kg fw) and other bioactive phytochemicals (mainly flavonoids and vitamin C) compared to their near isogenic conventional counterparts. Innovative (pre)industrial uses of HLY tomato include the following: (1) production of HLY sauces, juices, and powders; (2) supercritical-CO2 extraction of lycopene containing oleoresins; and (3) preparation of lycopene rich micro- and nano-carriers with improved stability and specific tissue delivery. In turn, the use of these innovative high-quality ingredients in the formulation of lycopene fortified foods, cosmetic products, nutraceuticals, and pharmaceuticals has been proposed as the basis of a novel highly profitable tomato product chain.  相似文献   
88.
Theory predicts that within‐population differences in the pace‐of‐life can lead to cohort splitting and produce marked intraspecific variation in body size. Although many studies showed that body size is positively correlated with fitness, many argue that selection for the larger body is counterbalanced by opposing physiological and ecological selective mechanisms that favour smaller body. When a population split into cohorts with different paces of life (slow or fast cohort), one would expect to detect the fitness–size relationship among and within cohorts, that is, (a) slower‐developing cohort has larger body size and higher fitness than faster‐developing cohort, and (b) larger individuals within each cohort show higher fitness than smaller individuals. Here, we test these hypotheses in capture–mark–recapture field surveys that assess body size, lifespan, survival and lifetime mating success in two consecutive generations of a partially bivoltine aquatic insect, Coenagrion mercuriale, where the spring cohort is slower‐developing than the autumn cohort. As expected, body size was larger in the slow‐developing cohort, which is consistent with the temperature‐size rule and also with the duration of development. Body size seasonal variation was greater in slow‐developing cohort most likely because of the higher variation in age at maturity. Concordant with theory, survival probability, lifespan and lifetime mating success were higher in the slow‐developing cohort. Moreover, individual body size was positively correlated with survival and mating success in both cohorts. Our study confirms the fitness costs of fast pace‐of‐life and the benefits of larger body size to adult fitness.  相似文献   
89.
The pathophysiological mechanisms leading to neuronal injury in middle cerebral artery occlusion (MCAO) model of cerebral stroke are complex and multifactorial that form the bases of behavioral deficits and inflammation mediated damage. The present study demonstrates the effect of piperine pretreatment (10 mg/kg b wt, once daily p.o. for 15 days) on cerebral ischemia-induced inflammation in male Wistar rats. The right middle cerebral artery was occluded for 2 h followed by reperfusion for 22 h. A maximum infarct volume (57.80 %) was observed in ischemic MCAO group. However, piperine administration prior to ischemia showed a significant reduction in infarct volume (28.29 %; p < 0.05) and neuronal loss (12.72 %; p < 0.01). As a result of piperine pretreatment, a significant improvement in behavioral outputs of MCAO rats (p < 0.05-0.01) was observed. Piperine successfully reduced the level of proinflammatory cytokines IL-1β, IL-6 and TNF-α, in ischemic group (p < 0.01). Ischemic group brain has shown edematous morphology with vacuolated architecture and pyknotic nuclei in H & E staining which was successfully ameliorated by piperine administration. Moreover, piperine also succeeded in lowering the expression of COX-2, NOS-2, and NF-κB (p < 0.01). Both cytosolic and nuclear NF-κB were down-regulated in ischemic group pre-administered with piperine (p < 0.01). The present study suggests that piperine is able to salvage the ischemic penumbral zone neurons by virtue of its anti-inflammatory property, thereby limiting ischemic cell death.  相似文献   
90.
Background & objectivesRosuvastatin calcium (RC) is a potent and competitive synthetic inhibitor of HMG-CoA reductase used for the treatment of dyslipidemia. Guggulipid obtained from Commiphora mukul is used in the treatment of a wide variety of diseases such as atherosclerosis, hypercholesterolemia, rheumatism, and obesity. The present study evaluates the pharmacokinetic and pharmacodynamic interactions between RC and the standardized guggulipid extract in rats.Materials and methodsThe guggulipid extract was standardized for the presence of guggulsterones. The pharmacokinetic interaction was determined after a single dose administration of RC alone or in combination with the guggulipid extract or after multiple-dose administration of RC alone or RC along with the guggulipid extract for 14 days. To determine the pharmacodynamic interaction, RC and guggulipid extract were administered to hyperlipidemic rats for 14 days. The level of significance was determined using unpaired student’s t-test, one way ANOVA, the post-ANOVA Tukey test.ResultsStandardization of guggulipid extract showed it contains 7.5%w/w of guggulsterones. Guggulipid extract increased the bioavailability of RC in both single-dose and multiple-dose studies. Guggulipid extract reduced the rate of absorption (Ka) of RC but showed an increase in maximum serum concentration (Cmax). An in-vitro study using isolated rat intestine revealed that guggulipid extract decreased the rate of absorption of RC in the intestinal lumen. The hypolipidemic activity of RC was augmented by the guggulipid extract in hyperlipidemic rats.Interpretation & conclusionTherefore it is concluded that guggulipid extract increases the bioavailability of RC by delaying its Ka and augments its hypolipidemic action. However, it is recommended that a combination of RC with guggulipid extract should be used only after an adverse effect(s) of this combination are determined.  相似文献   
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