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661.
Mohammad Mahdi Rabieh Mehdi Esfandiari Ali Asghar Seraj Russell Bonduriansky 《Biological journal of the Linnean Society. Linnean Society of London》2015,116(1):183-196
One‐size‐fits‐all and related hypotheses predict that static allometry slopes for male genitalia will be consistently lower than 1.0 and lower than the slopes for most other body parts (somatic traits). We examined the allometry of genitalic and somatic morphological traits in males and females of two species of noctuid moths, Spodoptera exigua (Hübner, [1808]) and Helicoverpa armigera (Hübner, [1808]). The relationship between genitalic traits and body size was generally strongly negative‐allometric in males but with no significant differences from 1.00 in females of the two species examined. However, in females, the slope of genital traits was also lower than the slopes for somatic traits. The relationship between somatic traits and the body size indicator was approximately isometric in most cases in males, except in four traits in S. exigua, in which the slopes showed slight negative allometry, and the hind tibia in H. armigera, in which the slope had positive allometry. However, in females, some somatic traits showed isometric and some other showed negative allometry in both species. The coefficients of variation (CV) for all structures in the males were low, not exceeding 10%. Genitalic traits showed significantly lower CV than somatic traits in males. In females, somatic traits showed lower CV than genitalic traits but with no significant difference in the H. armigera. Our observations of strongly negative allometry for genitalic traits in males are consistent with stabilizing selection on genital size and we suggest that male performance in interactions with females is the source of selection on male genital allometry. The difference in the degree of phenotypic variation between genitalic and somatic traits in the two studied species is attributed to the different developmental‐genetic architectures of these traits. Female genitalia showed a similar trend to the males, although the difference between genital and somatic traits was not significant in females. This finding suggests that selection is acting differently on male and female genitalia. Positive allometry of hind tibia in H. armigera may be a result of secondary sexual function. 相似文献
662.
Background
The present study was conducted in order to evaluate the fatty acid profile, anti-oxidant and anti-bacterial activities from the microwave aqueous extract of the leaves of three different varieties of Labisia pumila Benth.Results
The chemical analysis of the extract showed that fatty acids (palmitic, palmitoleic, stearic, oleic, linoleic and α-linolenic) acid as the main components in three varieties of L. pumila leaves. Furthermore, the obtained results of the anti-oxidant revealed that L. pumila var. alata contained higher anti-oxidative activities compared to var. pumila and var. lanceolata. However, these values were lower than the tested anti-oxidant standards. On the other hand, the aqueous leaf extracts in all three varieties of L. pumila were also found to inhibit a variable degree of antibacterial activities against eight bacteria (four Gram-positive and four Gram-negative bacteria).Conclusions
In this study, it was observed the leaves of three varieties of L. pumila exhibited variable patterns of fatty acids and the microwave aqueous extraction possess anti-oxidant and anti-bacterial activities. 相似文献663.
Marzieh Amizadeh Gholamreza Niknam Mahdi Arzanlou 《Biocontrol Science and Technology》2015,25(6):671-684
Bacillus thuringiensis var. kurstaki (Berliner) (Bt) has been suggested as a biological control agent for Tuta absoluta (Meyrick). The objective of this study was to determine the interaction between abamectin, azadirachtin, indoxacarb, chlorantraniliprole, dichlorvos and metaflumizone with Bt. Effect of recommended doses of the chemical insecticides on colonisation of Bt was also investigated in culture medium. Except for metaflumizone, none of the chemicals tested reduced the colonisation of Bt compared with control. Interaction between Bt and the chemical insecticides on 2nd-instar larvae was also assessed. In interaction tests, Bt was applied at LC50 level, 0, 12, 24 or 36 h after treating the larvae with LC10 or LC25 of the chemical insecticides. An antagonistic effect was observed in all treatments where Bt was applied immediately after the chemical insecticide. Also, antagonism was observed when treatment with Bt was done 12 h after azadirachtin and metaflumizone applications. Applying Bt 12 and 24 h after treatment with LC25 of chlorantraniliprole, dichlorvos and abamectin resulted in synergism. But, synergism with LC10 of dichlorvos and abamectin was observed only after 12 h. Additive effect was observed in the rest of the time and concentration combinations. Based on the results obtained, simultaneous use of the chemical insecticides tested and Bt is not recommended for T. absoluta control; and an appropriate time interval should be taken into consideration accordingly. 相似文献
664.
In this age of data‐driven science and high‐throughput biology, computational thinking is becoming an increasingly important skill for tackling both new and long‐standing biological questions. However, despite its obvious importance and conspicuous integration into many areas of biology, computer science is still viewed as an obscure field that has, thus far, permeated into only a few of the biology curricula across the nation. A national survey has shown that lack of computational literacy in environmental sciences is the norm rather than the exception [Valle & Berdanier (2012) Bulletin of the Ecological Society of America, 93, 373–389]. In this article, we seek to introduce a few important concepts in computer science with the aim of providing a context‐specific introduction aimed at research biologists. Our goal was to help biologists understand some of the most important mainstream computational concepts to better appreciate bioinformatics methods and trade‐offs that are not obvious to the uninitiated. 相似文献
665.
Trivendra Tripathi Mohammad Shahid Haris M. Khan Rahat Ali Khan Mashiatullah Siddiqui Abbas Ali Mahdi 《Saudi Journal of Biological Sciences》2011,18(4):411-418
This study was designed to investigate the functional roles of histamine and histamine H1-receptor agonist and antagonist in the development of liver function impairment in immunized rabbits. The study comprised of six groups containing 18 rabbits each. Group III–VI received histamine (100 μg/kg, s.c.), H1R-agonist (HTMT, 10 μg/kg, s.c.), H1R-antagonist (pheniramine, 10 mg/kg, i.m.), and H1R-antagonist (pheniramine, 10 mg/kg, i.m.) plus histamine (100 μg/kg, s.c.), respectively, b.i.d. for 10 days. Group I (negative control) and group II (positive control) received sterile distilled water intramuscularly b.i.d. for 10 days. Groups II–VI were immunized on day 3 with intravenous injection of SRBC (1 × 109 cells/ml). Blood samples were collected on pre-immunization day 0, as well as on days 7-, 14-, 21-, 28-, and 58-post-immunization. Biochemical parameters AST, ALT, alkaline phosphatase and bilirubin [total bilirubin (TB), direct bilirubin (DB), and indirect bilirubin (IB)] were determined. On each experimental day, the mean values of serum enzymes and bilirubin in group I and group II showed no significant changes while in group III, IV, V, and VI, these enzymes and bilirubin levels showed significant changes (p < 0.05), when compared with their experimental values within the group. The levels of serum enzymes and bilirubin showed significant difference (p < 0.05) in group III, IV, V, and VI on each experimental day, when compared with the corresponding values of each other, and also compared with the corresponding values of group I and II. Histamine, HTMT, pheniramine, and combination of histamine + pheniramine cause hepatic function impairment in terms of altered serum enzymes and bilirubin levels. The present findings suggest that HTMT causes moderate liver function impairment while others show mild impairment. 相似文献
666.
Targeted gene disruption experiments in Trichophyton mentagrophytes are impeded by the dominant of repair of DNA double strand breaks through a nonhomologous end joining pathway (NHEJ). Inactivation of human DNA ligase IV homologs, which is involved in the final step of the NHEJ pathway, has been shown to enhance homologous recombination (HR) frequency in filamentous fungi. To improve the frequency of HR in T. mentagrophytes, the lig4 homolog (TmLIG4) was disrupted. T. mentagrophytes lacking TmLIG4 showed no discernable phenotypic differences when compared to wild-type controls. Both mutant and parent strains had almost identical growth ability, sporulation rate and sensitivity to DNA damaging agents. When four different loci were disrupted in the TMLIG4-deficient mutant, HR frequencies reached as high as 93% depending on the locus, whereas they ranged from 0%-40% in the wild-type. These results suggest that studies in strains lacking TmLIG4 would help to improve our understanding of dermatophytosis by facilitating the genetic manipulation of dermatophytes. 相似文献
667.
668.
Sarita Dhuper Rukhsana A. Abdullah Laya Weichbrod Eman Mahdi Hillel W. Cohen 《Obesity (Silver Spring, Md.)》2011,19(1):128-133
Obesity, especially when complicated with hypertension, is associated with structural and functional cardiac changes. Recent studies have focused on the prognostic impact of the type of left ventricular (LV) geometric remodeling. This study looked at the prevalence and clinical correlates of LV geometric patterns and their relation to cardiac function in a sample of predominantly African‐American (AA) youth. Echocardiographic data was collected on 213 obese (BMI of 36.53 ± 0.53 kg/m2) and 130 normal‐weight subjects (BMI of 19.73 ± 0.21 kg/m2). The obese subjects had significantly higher LV mass index (LVMI; 49.6 ± 0.9 vs. 46.0 ± 1.0 g/m2.7, P = 0.01), relative wall thickness (RWT; 0.45 ± 0.00 vs. 0.40 ± 0.00, P < 0.001), left atrial (LA) index (33.2 ± 0.7 vs. 23.5 ± 0.6 ml/m, P < 0.001), more abnormal diastolic function by tissue Doppler E/Ea septal (7.5 ± 0.14 vs. 6.5 ± 0.12 ms, P < 0.001), E/Ea lateral (5.7 ± 0.12 vs. 4.8 ± 0.1 ms, P < 0.001), myocardial performance index (MPI; 0.43 ± 0.00 vs. 0.38 ± 0.00, P < 0.001), and Doppler mitral EA ratio (2.0 ± 0.04 vs. 2.4 ± 0.07, P < 0.001) but similar systolic function. Concentric remodeling (CR) was the most prevalent pattern noted in the obese group and concentric hypertrophy (CH) in the obese and hypertensive group. Obesity, hypertension, and CH were independent predictor of diastolic dysfunction. Systolic (SBP) and diastolic blood pressures (DBP) were the prime mediators for CH whereas obesity and diastolic blood pressure were predictors of CR. No significant association was observed between the geometric patterns and systolic function. Tracking LV hypertrophy (LVH) status and geometric adaptations in obesity may be prognostic tools for assessing cardiac risk and therapeutic end points with weight loss. 相似文献
669.
Li YJ Minear MA Rimmler J Zhao B Balajonda E Hauser MA Allingham RR Eghrari AO Riazuddin SA Katsanis N Gottsch JD Gregory SG Klintworth GK Afshari NA 《PloS one》2011,6(4):e18044
Fuchs endothelial corneal dystrophy (FECD) is a common, late-onset disorder of
the corneal endothelium. Although progress has been made in understanding the
genetic basis of FECD by studying large families in which the phenotype is
transmitted in an autosomal dominant fashion, a recently reported genome-wide
association study identified common alleles at a locus on chromosome 18 near
TCF4 which confer susceptibility to FECD. Here, we report
the findings of our independent validation study for TCF4 using
the largest FECD dataset to date (450 FECD cases and 340 normal controls).
Logistic regression with sex as a covariate was performed for three genetic
models: dominant (DOM), additive (ADD), and recessive (REC). We found
significant association with rs613872, the target marker reported by Baratz
et al.(2010), for all three genetic models (DOM:
P = 9.33×10−35;
ADD:
P = 7.48×10−30;
REC:
P = 5.27×10−6).
To strengthen the association study, we also conducted a genome-wide linkage
scan on 64 multiplex families, composed primarily of affected sibling pairs
(ASPs), using both parametric and non-parametric two-point and multipoint
analyses. The most significant linkage region localizes to chromosome 18 from
69.94cM to 85.29cM, with a peak multipoint
HLOD = 2.5 at rs1145315 (75.58cM) under the DOM
model, mapping 1.5 Mb proximal to rs613872. In summary, our study presents
evidence to support the role of the intronic TCF4 single
nucleotide polymorphism rs613872 in late-onset FECD through both association and
linkage studies. 相似文献
670.