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1.
Metabolism and some characteristics of lactobacilli isolated from the rumen of young calves 总被引:1,自引:0,他引:1
Fourteen strains of lactobacilli isolated from the rumen of young calves were studied to determine their biochemical characteristics, growth parameters, metabolism on lactose and sensitivity to 28 antimicrobial agents. Thirteen homofermentative strains belonged to Lactobacillus acidophilus and one heterofermentative strain resembled Lact. fermentum. The relevance of rumen lactobacilli to the nutrition of calves is discussed. 相似文献
2.
Carolin Röding Chris Stringer Rodrigo S. Lacruz Katerina Harvati 《American journal of physical anthropology》2023,180(2):352-369
Objectives
This study uses a virtual framework to examine the left maxillary fragment of the juvenile fossil from Mugharet el'Aliya, Morocco, found in association with an Aterian lithic industry. Previously, this fossil had been ascribed to modern humans or the Neanderthal lineage based on its “archaic”/“Neanderthal-like” features and apparent large size. Here, we conducted a novel 3D shape comparative analysis of the maxillary fragment to clarify its taxonomic affinities with regard to its size and ontogeny.Materials and Methods
Eighty Computed Tomography and surface scans representing ontogenetic samples of Homo sapiens and Homo neanderthalensis were used to capture species-specific differences. The toolkit of geometric morphometrics in combination with surface registration and an elastic iterative closest point algorithm were used to create a dataset of meshes with an identical number of corresponding vertices for the maxillae. Multivariate statistics were applied to Procrustes superimposed coordinates derived from the vertices of this dataset.Results
Our analysis showed affinities of the Mugharet el'Aliya individual with our H. sapiens sample, especially with a subadult individual from Qafzeh. No size-independent affinities with Neanderthals of comparable dental age could be identified.Discussion
Our results add to the evidence connecting fossils from western Asia, especially Qafzeh and Skhul, and the North African Aterian. Furthermore, Mugharet el'Aliya adds to our knowledge of the ontogenetic development of adult morphology that is frequently used to characterize hominin groups, for example, Neanderthals and modern humans. 相似文献3.
Souvik Seal Qunhua Li Elle Butler Basner Laura M. Saba Katerina Kechris 《PLoS computational biology》2023,19(1)
Inferring gene co-expression networks is a useful process for understanding gene regulation and pathway activity. The networks are usually undirected graphs where genes are represented as nodes and an edge represents a significant co-expression relationship. When expression data of multiple (p) genes in multiple (K) conditions (e.g., treatments, tissues, strains) are available, joint estimation of networks harnessing shared information across them can significantly increase the power of analysis. In addition, examining condition-specific patterns of co-expression can provide insights into the underlying cellular processes activated in a particular condition. Condition adaptive fused graphical lasso (CFGL) is an existing method that incorporates condition specificity in a fused graphical lasso (FGL) model for estimating multiple co-expression networks. However, with computational complexity of O(p2K log K), the current implementation of CFGL is prohibitively slow even for a moderate number of genes and can only be used for a maximum of three conditions. In this paper, we propose a faster alternative of CFGL named rapid condition adaptive fused graphical lasso (RCFGL). In RCFGL, we incorporate the condition specificity into another popular model for joint network estimation, known as fused multiple graphical lasso (FMGL). We use a more efficient algorithm in the iterative steps compared to CFGL, enabling faster computation with complexity of O(p2K) and making it easily generalizable for more than three conditions. We also present a novel screening rule to determine if the full network estimation problem can be broken down into estimation of smaller disjoint sub-networks, thereby reducing the complexity further. We demonstrate the computational advantage and superior performance of our method compared to two non-condition adaptive methods, FGL and FMGL, and one condition adaptive method, CFGL in both simulation study and real data analysis. We used RCFGL to jointly estimate the gene co-expression networks in different brain regions (conditions) using a cohort of heterogeneous stock rats. We also provide an accommodating C and Python based package that implements RCFGL. 相似文献
4.
5.
Arthas Flabouris Savvy Nandal Luke Vater Katerina Flabouris Alice O’Connell Campbell Thompson 《PloS one》2015,10(12)
Background
Observation charts are the primary tool for recording patient vital signs. They have a critical role in documenting triggers for a multi-tiered escalation response to the deteriorating patient. The objectives of this study were to ascertain the prevalence and incidence of triggers, trigger modifications and escalation response (Call) amongst general medical and surgical inpatients following the introduction of an observation and response chart (ORC).Methods
Prospective (prevalence), over two 24-hour periods, and retrospective (incidence), over entire hospital stay, observational study of documented patient observations intended to trigger one of three escalation responses, being a MER—Medical Emergency Response [highest tier], MDT—Multidisciplinary Team [admitting team], or Nurse—senior ward nurse [lowest tier] response amongst adult general medical and surgical patients.Results
Prevalence: 416 patients, 321 (77.2%) being medical admissions, median age 76 years (IQR 62, 85) and 95 (22.8%) Not for Resuscitation (NFR). Overall, 193 (46.4%) patients had a Trigger, being 17 (4.1%) MER, 45 (10.8%) MDT and 178 (42.8%) Nurse triggers. 60 (14.4%) patients had a Call, and 72 (17.3%) a modified Trigger. Incidence: 206 patients, of similar age, of whom 166 (80.5%) had a Trigger, 122 (59.2%) a Call, and 91 (44.2%) a modified Trigger. Prevalence and incidence of failure to Call was 33.2% and 68% of patients, respectively, particular for Nurse Triggers (26.7% and 62.1%, respectively). The number of Modifications, Calls, and failure to Call, correlated with the number of Triggers (0.912 [p<0.01], 0.631 [p<0.01], 0.988 [p<0.01]).Conclusion
Within a multi-tiered response system for the detection and response to the deteriorating patient Triggers, their Modifications and failure to Call are common, particularly within the lower tiers of escalation. The number of Triggers and their Modifications may erode the structure, compliance, and potential efficacy of structured observation and response charts within a multi-tiered response system. 相似文献6.
Christiane Elisabeth S?rensen Katerina Tritsaris Jesper Reibel Martin Lauritzen Erik Lykke Mortensen Merete Osler Anne Marie Lynge Pedersen 《PloS one》2016,11(3)
Background
The cell-cycle inhibitor and tumor suppressor cyclin dependent kinase inhibitor, p16ink4a, is one of the two gene products of the ink4a/ARF (cdkn2a) locus on chromosome 9q21. Up-regulation of p16ink4a has been linked to cellular senescence, and findings from studies on different mammalian tissues suggest that p16ink4a may be a biomarker of organismal versus chronological age.Objective
The aim of this study was to examine the immunolocalization pattern of p16ink4a in human labial salivary gland (LSG) tissue, and to analyze whether its expression level in LSGs is a peripheral correlate of cognitive decline in late midlife.Methods
The present study was a part of a study of causes and predictors of cognitive decline in middle-aged men in a Danish birth cohort. It is based on data from 181 male participants from the Danish Metropolit birth cohort, born in 1953, who were examined for age-associated alterations in cognition, dental health, and morphological and autonomic innervation characteristics of the LSGs. The participants were allocated to two groups based on the relative change in cognitive performance from young adulthood to late midlife. LSG biopsies were analyzed by qRT-PCR for the expression level of p16ink4a. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded sections of LSGs.Results
p16ink4a immunoreactivity was observed in LSG ductal, myoepithelial, and stromal cells, but not in acinar cells. The mean relative expression of p16ink4a in LSGs was higher in the group of participants with decline in cognitive performance. A logistic regression analysis revealed that the relative p16 expression was predictive of the participant’s group assignment. A negative correlation was found between relative p16ink4a expression and the participant’s standardized regression residuals from early adulthood to late midlife cognitive performance scores.Conclusions
p16ink4a expression in human LSGs may constitute a potential peripheral correlate of cognitive decline. Human labial salivary glands seem suitable for studies on organismal as opposed to chronological age. 相似文献7.
Nikola Hadzi‐Petrushev Marija Angelovski Katerina Rebok Vadim Mitrokhin Andre Kamkin Mitko Mladenov 《Journal of biochemical and molecular toxicology》2019,33(8)
For 22 days after monocrotaline injection two groups of rats received either of the monocarbonyl curcumin analogs (2E,6E)‐2,6‐bis(2‐bromobenzylidene)cycloxehanone (B2BrBC) and (2E,6E)‐2,6‐bis([2‐tri?uoromethyl]benzylidene)cyclohexanone (C66), and their right ventricle parameters were compared to those from the control and the monocrotaline injected animals. B2BrBC and C66 treatments did not prevent the monocrotaline‐induced right ventricular hypertrophy but attenuated the changes in antioxidant enzyme activities and reduced inflammation. The level of thiol‐based nonenzymatic antioxidants did not change in the function of monocrotaline or curcumin analogs treatment. However, due to its stronger antioxidant properties, only B2BrBC treatment was effective in the reduction of monocrotaline‐associated lipid peroxidation. The obtained results suggest that increasing the levels of antioxidant enzymes may not be sufficient to reduce oxidative stress and chronic inflammation optimally and our current study supports the potential of compounds with more than one beneficial biological activity as a promising treatment against the progression of cardiac hypertrophy. 相似文献
8.
Mark B. Bushuev Viktor P. Krivopalov Dmitrii Yu. Naumov Katerina A. Vinogradova Lilia A. Sheludyakova Stanislav V. Larionov 《Inorganica chimica acta》2010,363(7):1547-13900
A new bidentate chelating pyrazolylpyrimidine ligand bearing a strong electron-donating substituent, i.e. 4-(3,5-diphenyl-1H-pyrazol-1-yl)-6-(piperidin-1-yl)pyrimidine (L) (Scheme 1), has been synthesized and used to obtain the copper(II) complexes by reaction with CuCl2. The molar ratio Cu:L = 1:2 leads to isolation of a complex having CuL2Cl2 empirical formula, while the molar ratio Cu:L = 1:1 gives a complex with CuLCl2 empirical formula. The crystal structure of L as well as the structures of both complexes were studied by single crystal X-ray diffraction. The crystal structure of CuL2Cl2 compound is formed by trans-[CuL2Cl2] mononuclear molecules. Surprisingly, in contrast to the previous compound having molecular structure, the crystal structure of CuLCl2 consists of mononuclear [CuL2Cl]+ complex cations and dinuclear [Cu2Cl6]2− anions. Thus, formula of CuLCl2 complex can be represented as [CuL2Cl]2[Cu2Cl6]. In both complexes molecules of L adopt bidentate chelating coordination mode through N2 atom of pyrazole and N3 atom of pyrimidine rings forming five-membered CuN3C metallocycles. Owing to C-H···N interactions and π-π-stacking L molecules form 2D network. In the structure of trans-[CuL2Cl2] there exist double lone pair(N(piperidine))-π(pyrimidine) interactions and C-H···Cl contacts resulting in the formation of 1D chains. Layered 2D structure of [CuL2Cl]2[Cu2Cl6] results from C-H···Cl, C-H···π and double lone pair(Cl([CuL2Cl]+ complex cation)-π(pyrimidine) interactions. 相似文献
9.
A chimeric D1A dopaminergic receptor harboring the cytoplasmic tail (CT) of the D1B subtype (D1A-CTB) has been used previously to show that CT imparts high dopamine (DA) affinity and constitutive activity to the D1B receptors. However, the D1A-CTB chimera, unlike the D1B subtype, exhibits a significantly lower DA potency for stimulating adenylyl cyclase and a drastically lower maximal binding capacity (Bmax). Here, using a functional complementation of chimeric D1-like receptors, we have identified the human D1B receptor regions regulating the intramolecular relationships that lead to an increased DA potency and contribute to Bmax. We demonstrate that the addition of variant residues of the third extracellular loop (EL3) of the human D1B receptor into D1A-CTB chimera leads to a constitutively active mutant receptor displaying an increased DA affinity, potency, and Bmax. These results strongly suggest that constitutively active D1-like receptors can adopt multiple active conformations, notably one that confers increased DA affinity with decreased DA potency and Bmax and another that imparts increased DA affinity with a strikingly increased DA potency and Bmax. Overall, we show that a novel molecular interplay between EL3 and CT regulates multiple active conformations of D1-like receptors and may have potential implications for other G protein-coupled receptor classes. 相似文献
10.
The genus Reynoutria is represented by four taxa in the Czech Republic: Reynoutria japonica var. japonica, R. japonica var. compacta, R. sachalinensis and R. xbohemica. By using flow cytometry, cytological variability within the genus is described based on 257 Reynoutria samples. The varieties of R. japonica are cytologically uniform, var. japonica is exclusively octoploid (2n = 8x = 88) and var. compacta occurs only as a tetraploid (2n = 4x = 44), but R. sachalinensis and R. xbohemica exhibit some variation in chromosome numbers. Reynoutria sachalinensis is predominantly tetraploid (2n = 4 x = 44), but also occurs occasionally as hexaploid and octoploid cytotypes. The most common ploidy level in R. xbohemica is hexaploid (2n = 6x = 66), but tetraploid and octoploid clones were also found. The four taxa occurring in the Czech Republic are described briefly and the possible origins of the cytotypes discussed. 相似文献