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101.
102.
103.
Studies of mediator involvement in cooling-induced alterations of guinea pig tracheal smooth muscle contractility 总被引:1,自引:0,他引:1
R C Kolbeck B A Chaudhary W A Speir 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1988,187(1):82-88
Heat loss from airway smooth muscle is a potent stimulus which causes substantial, but poorly understood, alterations in muscle tension. This study considered the involvement of endogenous mediators in cooling-induced tension changes in incubated guinea pig trachea. Smooth muscle tension was monitored in tracheal cylinders which were carefully cooled from 37 to 30 degrees C in the presence or absence of various inotropic mediators. In our study, cooling alone, at a rate of 1 degree C/min, was associated with an average loss of smooth muscle tension of 88.2 mg. Cooling tracheal tissue that had been previously exposed to 3 X 10(-6) M histamine, however, caused an additional increase in tracheal tension of 133 mg, over and above that caused by histamine alone. In the presence of 10(-5) M prostaglandin F2 alpha, or 10(-5) M thromboxane B2, cooling was associated with respective losses of smooth muscle tension of 211.4 and 211.2 mg, as compared to the tension associated with these mediators when they were used alone under control conditions. When the speed of tracheal cooling was increased to 40 degrees C/min, there was a slight increase in tension for 20 sec followed by a pronounced and sustained relaxation. The mechanisms involved in the response of airway smooth muscle to cooling are complex. The results of our study, however, suggest that mediators may play a role in the cooling-induced alterations of airway smooth muscle tension. 相似文献
104.
Renuka Chaudhary Terje Raudsepp Xin-Yuan Guan Hongen Zhang Bhanu P. Chowdhary 《Mammalian genome》1998,9(1):44-49
Microdissected arm specific paints (ASPs) for human (HSA) chromosomes (Chrs) 2, 5, 6, 16, and 19 were used as probes on pig
(SSC) and horse (ECA) metaphase chromosomes. Regions homologous to individual human arms were delineated in the two species
studied. Of the ten ASPs used, HSA6 and 16 ASPs showed complete synteny conservation of individual arms as single blocks/arms
both in pig and horse. A similar trend was, in general, also observed for HSA19 ASPs. However, contrary to these observations,
synteny conservation of individual arms of HSA2 and HSA5 was not observed in pig and horse. The arm specific painting data,
coupled with the available gene mapping data, showed that, although HSA2 corresponded to two arms/chromosomes each in pig
and horse, the breakpoint of this synteny in humans was not located at the centromere, but at HSA2q13 band. Similarly, arm
specific paints for HSA5 showed that of the two blocks/chromosomes painted in pig and horse, one corresponded to HSA5q13-pter,
the other to HSA5q13-qter. The findings suggest that 5q13 band may also be an evolutionary break point, similar to the one
detected on HSA2q13. The microdissected human arm specific painting probes used in the present work provide more accurate
and refined comparative information on pig and horse chromosomes than that available through the use of human whole chromosome
specific paints.
Received: 1 June 1997 / Accepted: 5 September 1997 相似文献
105.
The present study focusses on the effects of pH, temperature, intensity of white, red far-red light on zygospore germination
in the filamentous green algaSpirogyra hyalina. Maximum germination of zygospores occurred at pH 8.0 and 25°C. Germination of zygospores was favored by white light at an
intensity of 3–4 klx. Red light resulted in higher germination when applied at the beginning or in the middle of the dark
period, while far-red light decreased zygospore germination. Red light in the middle of the dark period was found to be most
effective for germination. These observations suggest a possible presence of the phytochrome system in the test alga contributing
to its morphogenetic response. 相似文献
106.
107.
Nguyen Huy Thuan Amit Kumar Chaudhary Duong Van Cuong Nguyen Xuan Cuong 《Journal of industrial microbiology & biotechnology》2018,45(3):175-185
Microbial cells have extensively been utilized to produce value-added bioactive compounds. Based on advancement in protein engineering, DNA recombinant technology, genome engineering, and metabolic remodeling, the microbes can be re-engineered to produce industrially and medicinally important platform chemicals. The emergence of co-culture system which reduces the metabolic burden and allows parallel optimization of the engineered pathway in a modular fashion restricting the formation of undesired byproducts has become an alternative way to synthesize and produce bioactive compounds. In this study, we present genetically engineered E. coli-based co-culture system to the de novo synthesis of apigetrin (APG), an apigenin-7-O-β-d-glucopyranoside of apigenin. The culture system consists of an upstream module including 4-coumarate: CoA ligase (4CL), chalcone synthase, chalcone flavanone isomerase (CHS, CHI), and flavone synthase I (FNSI) to synthesize apigenin (API) from p-coumaric acid (PCA). Whereas, the downstream system contains a metabolizing module to enhance the production of UDP-glucose and expression of glycosyltransferase (PaGT3) to convert API into APG. To accomplish this improvement in titer, the initial inoculum ratio of strains for making the co-culture system, temperature, and media component was optimized. Following large-scale production, a yield of 38.5 µM (16.6 mg/L) of APG was achieved. In overall, this study provided an efficient tool to synthesize bioactive compounds in microbial cells. 相似文献
108.
109.
Doongar Ram Chaudhary Aditya Prakash Rathore Bhavanath Jha 《Ecological Research》2018,33(6):1207-1218
The present study determined the plant biomass (aboveground and belowground) of Salicornia brachiata from six different salt marshes distributed in Indian coastal area over one growing season (September 2014–May 2015). The nutrients concentration and their pools were estimated in plant as well as soil. Belowground biomass in S. brachiata was usually lower than the aboveground biomass. Averaged over different locations, highest biomass was observed in the month of March (2.1 t ha?1) followed by May (1.64 t ha?1), February (1.60 t ha?1), November (0.82 t ha?1) and September (0.05 t ha?1). The averaged aboveground to belowground ratio was 12.0. Aboveground and belowground biomass were negatively correlated with pH of soil, while positively with soil electrical conductivity. Further, there were positive relationships between organic carbon and belowground biomass; and available sodium and aboveground biomass. The nutrient pools in aboveground were always higher than to belowground biomass. Aboveground pools of carbon (543 kg ha?1), nitrogen (48 kg ha?1), phosphorus (4 kg ha?1), sodium (334 kg ha?1) and potassium (37 kg ha?1) were maximum in the month of March 2015. Bioaccumulation and translocation factors for sodium of S. brachiata were more than one showing tolerance to salinity and capability of phytoremediation for the saline soil. 相似文献
110.
Mark A. Seefeld Hong Lin Joerg Holenz Dave Downie Brian Donovan Tingting Fu Kishore Pasikanti Wei Zhen Matthew Cato Khuram W. Chaudhary Pat Brady Tania Bakshi Dwight Morrow Sridharan Rajagopal Swapan Kumar Samanta Naveena Madhyastha Bharathi Mohan Kuppusamy Robert W. Dougherty Yasuji Matsuoka 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3793-3797
Neuronal voltage-gated potassium channels, KV7s, are the molecular mediators of the M current and regulate membrane excitability in the central and peripheral neuronal systems. Herein, we report novel small molecule KV7 openers that demonstrate anti-seizure activities in electroshock and pentylenetetrazol-induced seizure models without influencing Rotarod readouts in mice. The anti-seizure activity was determined to be proportional to the unbound concentration in the brain. KV7 channels are also expressed in the bladder smooth muscle (detrusor) and activation of these channels may cause localized undesired effects. Therefore, the impact of individual KV7 isoforms was investigated in human detrusor tissue using a panel of KV7 openers with distinct activity profiles among KV7 isoforms. KCNQ4 and KCNQ5 mRNA were highly expressed in detrusor tissue, yet a compound that has significantly reduced activity on homomeric KV7.4 did not reduce detrusor contraction. This may suggest that the homomeric KV7.4 channel plays a less significant role in bladder contraction and further investigation is needed. 相似文献