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871.
Mustafa Yaman 《Theoretical biology forum》2003,96(1):137-144
Turkey is first among all hazelnut producing countries. However, it lags far behind them in terms of amount harvested per unit area. A main reason for this is that hazelnut has many agricultural pests that can not be effectively controlled. Chemical pesticides utilized to control these pests have hazardous effects on the environment. Increasing problems with resistance of these pests to most commonly used synthetic insecticides have spurred the search for alternative pest management strategies that would reduce reliance on synthetic insecticides. Biological control of hazelnut pests is an alternative control method to chemical pesticides. It is very important ecologically because of production of honey, milk and fish in the surrounding areas of hazelnut fields in Turkey. Several promising bacteriological studies have been made to find some biological control agents against these pests in Turkey. This paper presents a review of the current status of bacteriological studies on biological control of hazelnut pests in Turkey. 相似文献
872.
S. Afaq-Husain Mustafa Shameel K. Usmanghani Mansoor Ahmad Shaista Perveen Viqar Uddi Ahmad 《Journal of applied phycology》1991,3(2):111-113
A chloroform extract of freeze-dried Hypnea pannosa J. Ag., collected from the intertidal region near Karachi, Pakistan, furnished three bromine-containing secondary metabolites.
These were characterised, using spectroscopic techniques, as 10-bromo-7, 12-dihydroxy-Δ3, 4-laurene, filiformin and filiforminol. This is the first report of halogenated terpenoids from the genus Hypnea.
author for correspondence 相似文献
873.
874.
BioMetals - The objective of the present study was to investigate the impact of zinc and copper on some biomarkers in a model organism Galleria mellonella L. We investigated the effects of Cu and... 相似文献
875.
Alice Lee Scott P. Fraser Mustafa B. A. Djamgoz 《Journal of cellular physiology》2019,234(12):23066-23081
The MDA-MB-231 cell line was used as a model of triple negative breast cancer to investigate the interaction of β-adrenergic receptor (β-AR) and voltage-gated sodium channel (VGSC). There was significant (86%) overlap in their expression. Short-term (acute) application of the β-AR antagonist propranolol (25 μM) led to reduction of peak current and quickening of current inactivation (the latter occurred only in 5% fetal bovine serum). Long-term (48 hr) incubation with propranolol (25 μM) resulted in several changes in VGSC characteristics: shifts in (a) current-voltage relationship and (b) steady-state inactivation, both to more negative potentials and (c) the slowing of recovery from inactivation. We then investigated the effects of propranolol and ranolazine, a blocker of VGSC activity, alone and in combination, on lateral motility and Matrigel invasion. These assays were carried out under hypoxic conditions more representative of tumor progression. Propranolol (2.5 and 25 μM) and ranolazine (5 μM), and their combination inhibited lateral motility. Also, propranolol (25 μM) and ranolazine (5 μM), and their combination inhibited invasion. However, no synergy was observed in the pharmacological combinations for both assays. Propranolol also significantly decreased total neonatal Nav1.5 protein expression, the predominant VGSC subtype expressed in these cells. We conclude (a) that β-AR and VGSC are functionally coupled in MDA-MB-231 cells; (b) that propranolol has direct blocking action on the VGSC; (c) that the action of propranolol is modulated by serum; and (d) that the antimetastatic cellular effects of propranolol and ranolazine are not additive. 相似文献
876.
Akif Evren Parlak Suat Tekin Arzu Karatepe Pelin Koparir Hafize Telceken Ali Osman Ceribası Mustafa Karatepe 《Journal of cellular biochemistry》2019,120(7):11809-11819
1,2,4-Triazoles are used as antifungal, antibacterial, antimicrobial, and antioxidant against some oxidative radical species. Recently, many 1,2,4-triazoles continue to be synthesized. In this study, the effect of the 1,2,4-triazole derivatives on human colon cancer (HT29) was investigated in vitro and in vivo in rats. MTT test was applied to in in vitro experiments. For in vivo study, rats were divided into seven groups as follows: Control group (negative control), azoxymethane (AOM), AOM + cisplatin 15, AOM + L1, AOM + L2, AOM + L3, and AOM + L4. To create colon cancer, the AOM injection was injected subcutaneously at a dose of 15 mg/kg, three times (once weekly). The in vivo studies were completed at 28 weeks. It was found that the 1,2,4-triazole derivatives reduced the cell viability (P < 0.05). In all animals in the experimental groups, mild dysplasia was detected in 100% of the colon mucosal epithelium. Severe dysplasia and adenocarcinoma were observed in L1 groups. As a result, this study determined that the 1,2,4-triazole derivatives exhibit antitumor activity. 相似文献
877.
878.
Akhil Chameettachal Valrie Vivet-Boudou Fathima
Nuzra
Nagoor Pitchai Vineeta
N Pillai Lizna
Mohamed Ali Anjana Krishnan Serena Bernacchi Farah Mustafa Roland Marquet Tahir
A Rizvi 《Nucleic acids research》2021,49(8):4668
Retroviral RNA genome (gRNA) harbors cis-acting sequences that facilitate its specific packaging from a pool of other viral and cellular RNAs by binding with high-affinity to the viral Gag protein during virus assembly. However, the molecular intricacies involved during selective gRNA packaging are poorly understood. Binding and footprinting assays on mouse mammary tumor virus (MMTV) gRNA with purified Pr77Gag along with in cell gRNA packaging study identified two Pr77Gag binding sites constituting critical, non-redundant packaging signals. These included: a purine loop in a bifurcated stem-loop containing the gRNA dimerization initiation site, and the primer binding site (PBS). Despite these sites being present on both unspliced and spliced RNAs, Pr77Gag specifically bound to unspliced RNA, since only that could adopt the native bifurcated stem–loop structure containing looped purines. These results map minimum structural elements required to initiate MMTV gRNA packaging, distinguishing features that are conserved amongst divergent retroviruses from those perhaps unique to MMTV. Unlike purine-rich motifs frequently associated with packaging signals, direct involvement of PBS in gRNA packaging has not been documented in retroviruses. These results enhance our understanding of retroviral gRNA packaging/assembly, making it not only a target for novel therapeutic interventions, but also development of safer gene therapy vectors. 相似文献
879.
İsmail Yapıcı Ahmet Altay Beyza Öztürk Sarıkaya Mustafa Korkmaz Alptuğ Atila İlhami Gülçin Ekrem Köksal 《化学与生物多样性》2021,18(3):e2000812
In this study, phenolic composition, and in vitro biological activities of ethyl acetate (EAE) and methanol (ME) extracts obtained from the aerial parts of endemic Tanacetum erzincanense were investigated. Total phenolic and flavonoid content of the extracts were determined by Folin-Ciocalteu and aluminum chloride colorimetric methods, respectively. Antioxidant capacity of the extracts was evaluated over radical scavenging (DPPH and ABTS) and metal ion reducing power (FRAP and CUPRAC) tests. Individual phenolic compounds in ME was analyzed by high-performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF/MS). Cell inhibitory potential of the extracts was tested against colorectal adenocarcinoma (HT-29), breast adenocarcinoma (MCF-7), and hepatocarcinoma (HepG2) cells by 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay. The results showed that ME contains higher TPC (64.4 mg GAE/g) and TFC (62.2 mg QE/g) than those of EAE (41.5 mg GAE/g and 40.0 mg QE/g). LC-ESI-QTOF/MS analysis revealed that ME is rich in phenolic compounds, namely, chlorogenic acid, apigenin, quercetin, luteolin, and diosmetin. Antioxidant assay results indicated that ME possess stronger activity than EAE and a power that competes with synthetic antioxidants. XTT assay results demonstrated that although both extracts displayed a considerable cytotoxicity against the tested cancer cell lines in a time and dose-dependent manner, ME expressed its selective inhibitory action towards MCF-7 cells with an IC50 value of 20.4 μg/mL for 72 h. These results may serve as a basis for further in vivo studies to examine the potential applications of T. erzincanense in food and pharmaceutical industries. 相似文献
880.
Muhammet Mustafa Alpaslan 《Science activities》2017,54(2):38-47
In recent years, the integration of science and mathematics has become popular among educators because of its potential benefits for student learning. The purpose of this study is to introduce a two-day interdisciplinary lesson that brings science and mathematics concepts together, actively engaging students in working with percentages of the ingredients in mixtures with the concept of torque. Participation in this Grade 7-9 lesson provides opportunities for students to learn from both content areas as they progress through a variety of science process skills. 相似文献