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941.
Fareeha Saleh Ali Hussain Tahira Younis Shahzad Ali Muhammad Rashid Ahmad Ali Ghullam Mustafa Faiza Jabeen Ameena A. AL-Surhanee Maryam M. Alnoman Samina Qamer 《Saudi Journal of Biological Sciences》2020,27(12):3499-3504
Amylases take part with vital role in industries such as food, fermentation; starch processing, textile and paper etc. Increasing amylases demand, high nutrient expenditure and environmental pollution have forced to utilize agro-industrial residues as a low-cost feedstock for enzyme production. In present study, three soil samples were collected from agro-industrial waste dumping areas in District Faisalabad. Ten thermophilic bacterial isolates were separated at 55 °C on the basis of colonial morphology, three isolates (F6, F11, F17) showed prominent zone of clearance applying iodine test on starch agar plates. Bacterial isolate F-11 showed highest amylase activity with DNS method and molecularly identified through 16S RNA sequencing as Bacillus sp. with Accession number MH917294. Four unconventional food wastes (banana, lemon, mango and potato) pretreated with 0.8% sulphuric acid concentrations taking 1000 g/L weight released the highest sugars contents and phenolic components. Maximum amylase activity i.e. 29.23 mg/ml was achieved in mango waste at, 40 °C, with pH 6.0 and 0.17% nitrogenous source adding 8% inoculum size (2 days old) using Response Surface Methodology (RSM) for optimization. Crude amylase confirmed its efficiency in starch hydrolysis that suggested it as potential candidate for application in starch industries. 相似文献
942.
Jonathan How Ai Zhang Margaret Phillips Aline Reynaud Si Yan Lu Lucy Xin Pan Hai Ting Ho Yin Hoe Yau Albert Guskov Konstantin Pervushin Susana Geifman Shochat Said Eshaghi 《PloS one》2013,8(1)
STIM1 is a Ca2+ sensor within the ER membrane known to activate the plasma membrane store-operated Ca2+ channel upon depletion of its target ion in the ER lumen. This activation is a crucial step to initiate the Ca2+ signaling cascades within various cell types. Human STIM1 is a 77.4 kDa protein consisting of various domains that are involved in Ca2+ sensing, oligomerization, and channel activation and deactivation. In this study, we identify the domains and boundaries in which functional and stable recombinant human STIM1 can be produced in large quantities. To achieve this goal, we cloned nearly 200 constructs that vary in their initial and terminal residues, length and presence of the transmembrane domain, and we conducted expression and purification analyses using these constructs. The results revealed that nearly half of the constructs could be expressed and purified with high quality, out of which 25% contained the integral membrane domain. Further analyses using surface plasmon resonance, nuclear magnetic resonance and a thermostability assay verified the functionality and integrity of these constructs. Thus, we have been able to identify the most stable and well-behaved domains of the hSTIM1 protein, which can be used for future in vitro biochemical and biophysical studies. 相似文献
943.
Srinivasa Rao Jada Ahmad Sazali Hamzah Nordin Haji Lajis Mohammad Said Saad Malcolm F.G. Stevens Johnson Stanslas 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3)
Andrographolide 1, a diterpenoid lactone of the plant Andrographis paniculata, known to possess antitumour activity in in vitro and in vivo breast cancer models was subjected to semisynthesis leading to the preparation of a number of novel compounds. These compounds exhibited in vitro antitumour activity with moderate to excellent growth inhibition against MCF-7 (breast) and HCT-116 (colon) cancer cells. Compounds 3,19-(2-chlorobenzylidene)andrographolide(5), 3,19-(3-chlorobenzylidene)andrographolide(6), 3,19-(3-fluorobenzylidene)andrographolide(7), 3,19-(4-fluorobenzylidene)andrographolide(8), 3,19-(2-fluorobenzylidene)andrographolide(10), 3,19-(2-chloro-5-nitrobenzylidene)andrographolide (21), 3,19-(4-chlorobenzylidene)andrographolide(30) and 3,19-(2-chloro-4-fluorobenzylidene) andrographolide(31) were also screened against 60 NCI (National Cancer Institute, USA) human tumour cell lines derived from nine cancer cell types. 相似文献
944.
Bokhari H Said F Syed MA Mughal A Kazi YF Kallonen T He Q King AJ Heuvelman K Mooi FR 《FEMS immunology and medical microbiology》2011,63(3):373-380
Although a whole-cell pertussis vaccine was introduced in Pakistan in 1980, little is known about the pertussis prevalence and circulating strains in Pakistan. The aim of this study was to analyze Bordetella parapertussis isolates circulating between 2005 and 2009 in Pakistan and to compare them with those found in other countries during different periods. A total of 59 (7.35%) B.?parapertussis isolates from 802 subjects (median age, 3?years) from Pakistan, with pertussis-like symptoms were investigated. We carried out genotyping and DNA microarray analyses on these isolates and compared them with some international isolates of B.?parapertussis. We found that the allele for pertactin (prn) found in strains studied from Pakistan was identical to the predominant type found in Europe. We showed that B.?parapertussis isolates circulating in Pakistan are part of the same pulsed-field gel electrophoresis group to those circulating in Finland during the period of 1982-2007. Finally, microarray analysis confirmed that the isolates collected in Pakistan, were quite similar to international strains. Overall, these results confirm that B.?parapertussis is extremely monomorphic. The high isolation rate of B.?parapertussis (7.35%) compared to Bordetella pertussis (0.5%) may suggest that the whole-cell vaccine used in Pakistan is effective against B.?pertussis (0.5% infections detected), but much less so against B.?parapertussis. 相似文献
945.
Al-Alawi AA Al-Marhubi IM Al-Belushi MS Soussi B 《Marine biotechnology (New York, N.Y.)》2011,13(5):893-899
Carrageenophyte red seaweed from Oman, Hypnea bryoides, extracted using three different processes: an aqueous, a mild alkaline, and a more vigorous alkaline extraction was investigated.
The resulting extract precipitated by alcohol was subject to chemical and rheological measurements. The total carbohydrate
[ranged from 36.78 to 41.65 g/100 g], and ash [39.04 to 43.11 g/100 g] were the most abundant components in H. bryoides and contrary to the two, lipid content was found at a minimum [ranging from 2.95 to 3.38 g/100 g]. Alkali treatment with
NaOH allowed complete conversion of kappa (κ) carrageenan form as detected by FTIR analysis. Total yield by alkali treatments
gave higher yields (33%) compared with aqueous treatments (12%). However, subsequent aqueous treatment produced mixed carrageenan
(μ and κ) with higher molecular weight compared with the alkali treatments which produced single carrageenan form (κ) with
molecular weight of 4.1 × 105 Da. The effects of thermal history on gel–sol and sol–gel transition were investigated by differential scanning calorimeter
(DSC) and rheology on a pure sample and 1.5% κ-carrageenan mixture added with 30 mM KCl. Transition temperatures from DSC
and rheology showed comparable results and were in good agreement with those previously reported. 相似文献
946.
Said R Pohanka A Andersson M Beck O Abdel-Rehim M 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2011,879(11-12):815-818
Remifentanil is a synthetic short-acting opioid with a short half-life that is being used during anaesthesia of small children. In this work an LC-MS/MS method for remifentanil quantification in 20 μL volume of human plasma was developed and validated in connection with a clinical study on neonatal children. Sample preparation was performed with micro extraction in packed syringe (MEPS), which is a miniaturization of solid phase extraction. For this method a mixed phase sorbent M1 (C8, cation exchange), and a protocol for basic compound extraction was followed. Remifentanil-(13)C(6) was used as internal standard. For chromatographic separation, a C18 analytical column with gradient elution was used with mobile phase consisting of aqueous 0.1% formic acid and methanol. The total analysis time was 5.0 min and the measuring range was between 0.05 and 50 ng/mL. Precision and accuracy were with acceptance criteria of ±15%. Plasma samples were stable for 5 weeks at -20°C and for 4h at room temperature while 50% was lost after 24h. This method was successfully applied for remifentanil determination in clinical samples and results agreed with a reference method. With this method using MEPS, a low limit of quantification and much reduced sample volume was obtained as compared with previous methods. 相似文献
947.
Abdallah Y Kasseckert SA Iraqi W Said M Shahzad T Erdogan A Neuhof C Gündüz D Schlüter KD Tillmanns H Piper HM Reusch HP Ladilov Y 《Journal of cellular and molecular medicine》2011,15(11):2478-2485
Uncontrolled release of Ca(2+) from the sarcoplasmic reticulum (SR) contributes to the reperfusion-induced cardiomyocyte injury, e.g. hypercontracture and necrosis. To find out the underlying cellular mechanisms of this phenomenon, we investigated whether the opening of mitochondrial permeability transition pores (MPTP), resulting in ATP depletion and reactive oxygen species (ROS) formation, may be involved. For this purpose, isolated cardiac myocytes from adult rats were subjected to simulated ischemia and reperfusion. MPTP opening was detected by calcein release and by monitoring the ΔΨ(m). Fura-2 was used to monitor cytosolic [Ca(2+)](i) or mitochondrial calcium [Ca(2+)](m), after quenching the cytosolic compartment with MnCl(2). Mitochondrial ROS [ROS](m) production was detected with MitoSOX Red and mag-fura-2 was used to monitor Mg(2+) concentration, which reflects changes in cellular ATP. Necrosis was determined by propidium iodide staining. Reperfusion led to a calcein release from mitochondria, ΔΨ(m) collapse and disturbance of ATP recovery. Simultaneously, Ca(2+) oscillations occurred, [Ca(2+)](m) and [ROS](m) increased, cells developed hypercontracture and underwent necrosis. Inhibition of the SR-driven Ca(2+) cycling with thapsigargine or ryanodine prevented mitochondrial dysfunction, ROS formation and MPTP opening. Suppression of the mitochondrial Ca(2+) uptake (Ru360) or MPTP (cyclosporine A) significantly attenuated Ca(2+) cycling, hypercontracture and necrosis. ROS scavengers (2-mercaptopropionyl glycine or N-acetylcysteine) had no effect on these parameters, but reduced [ROS](m). In conclusion, MPTP opening occurs early during reperfusion and is due to the Ca(2+) oscillations originating primarily from the SR and supported by MPTP. The interplay between Ca(2+) cycling and MPTP promotes the reperfusion-induced cardiomyocyte hypercontracture and necrosis. Mitochondrial ROS formation is a result rather than a cause of MPTP opening. 相似文献
948.
949.
Denisse Sepulveda Diego Rojas-Rivera Diego A. Rodríguez Jody Groenendyk Andres Köhler Cynthia Lebeaupin Shinya Ito Hery Urra Amado Carreras-Sureda Younis Hazari Mireille Vasseur-Cognet Maruf M.U. Ali Eric Chevet Gisela Campos Patricio Godoy Tomas Vaisar Béatrice Bailly-Maitre Kazuhiro Nagata Claudio Hetz 《Molecular cell》2018,69(2):238-252.e7
950.