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121.
Edith Doucet Jacques Bourbon Michel Rieutort Lea Marin Claude Tordet 《In vitro cellular & developmental biology. Plant》1987,23(3):189-198
Summary Lung organ culture has been a widely used system for studying differentiation and maturation of alveolar epithelium through
various culture conditions. The purpose of this work was to carefully characterize in vitro lung biochemical diffeentiation
through isolation of surfactant fraction from tissue and to search for optimal culture conditions. Fetal rat lung was explanted
on the 18th gestational day for studying glycogen storage, and on the 20th gestational day for studying surfactant accretion,
and cultivated for 48 h. Morphologic differentiation was studies byelectron microscopy tissue explanted on the 17th or 18th
gestational days and cultivated for various times. Glycogen storage was greater on fluid medium, although less than occurring
in vivo. Cellular integrity and surfactant accumulation were maximal on a semisolid medium containing 0.5% agar. Use of O2-CO2 instead of air-CO2 for gassing the explants slighlty decreased phospholipid accumulation. Among media used in previous lung culture studies,
Waymouth MB 752/1 was the only one to allow net glycogen accumulation in vitro. The most favorable media for surfactant phospholipid
accretion were Waymouth MB 752/1, Eagle’s minimum essential and its Dulbeccco’s modification, CMRL 1066, and NCTC 109. They
allowed a 12- to 14-fold increase of surfactant fraction phospholipids in vitro, which is similar to the increase occurring
in vivo during the same peiod. Ham’s F10 and F12 media allowed a six fold increase. RPMI 1640 and medium 199 (M199) allowed
only a three fold increase. Phospholipid concentration in nonsurfactant fraction only doubled during culture, and differences
between various media were much less marked. DNA concentration changed little during culture. Morphologic differentiation
of epithelial cells was advanced as compared with in vivo timing in a medium allowing maximal surfactant accretion (Waymouth
MB 752/1) but not in a medium allowing low surfactant increase (RPMI 1640). The possible role of compositional differences
between media is discussed. 相似文献
122.
Physical conditions of propagation media and their influence on the rooting of cuttings 总被引:1,自引:0,他引:1
Hans R. Gislerød 《Plant and Soil》1983,75(1):1-14
Summary The formation and subsequent growth of roots by cuttings of poinsettia, hydrangea, rose and azalea in various propagation media, Jiffy-7, Jiffy-9 and Grodan under different conditions of aeration was investigated. The interrelationships of the effects of air content of the media, temperature and light intensity on the rooting of poinsettia cuttings was also studied.With low air contents (0 cm moisture tension) in the propagation media the formation and growth of roots was strongly inhibited. The rooting performance of rose appeared to be less affected by the poor aeration. Increasing air content improved rooting but best results were obtained at moisture tensions of 4 to 8 cm. Rooting seems to be better correlated with oxygen diffusion rate (ODR) than with air content.For poinsettia cuttings the optimum temperature for rooting was 24 to 28°C. At low temperatures rooting was delayed while at higher temperatures it was almost completely inhibited. Callus formation increased with temperature but decreased with increasing moisture tension. Conditions which induced large callus formation inhibited root formation.High light intensity during rooting reduced overall rooting performance and the inhibition was most pronounced in conjunction with high moisture tensions.Report No. 255. 相似文献
123.
Use of cereals as basal medium for the formulation of alternative culture media for fungi 总被引:1,自引:0,他引:1
A.?O.?AdesemoyeEmail author C.?O.?Adedire 《World journal of microbiology & biotechnology》2005,21(3):329-336
Summary The feasibility of developing alternative media to different culture media particularly potato dextrose agar was assessed using local cereal species as the basal media. Three cereal meal extracts – corn, sorghum and millet – were prepared, using them as substitute for the potato in potato dextrose agar. Potato dextrose agar (PDA) was the standard set up with which the performances of the formulated media were compared. Eight genera of fungi (Aspergillus niger, Fusarium moniliforme, Penicillium sp., Cercospora sp., Curvularia palescens, Botryodiplopodia sp., Rhizopus sp. and Rhodotorula rubra) were isolated and pure cultures of each species aseptically inoculated onto the three different formulated media including PDA and allowed to grow. Their growths were measured at 24, 48, 72, and 96 h after inoculation, using diameter of growth as an index. The set up was repeated thrice for each species on the three formulated media and the control (PDA). Growth of all the fungal species were observed to be about the same or sometimes better in the formulated media relative to those on the standard set up, except for Rhodotorula rubra. The radius of growth of F. moniliformehad an average of 15 + 0.58 mm on corn-dextrose agar relative to 12 mm on PDA at 96 h while Cercospora sp. measured 30 + 0.58 mm on millet-meal dextrose agar relative to 37 + 1.16 mm at 48 h. Botryodiplopodia sp. grew through the whole diameter of the plate (covering the total length of the radius of 45 mm) in both sorghum-meal and PDA at 96 h. 相似文献
124.
H. O. Jauregui P. N. McMillan J. Driscoll S. Naik 《In vitro cellular & developmental biology. Plant》1986,22(1):13-22
Summary Long-term monolayer cultures of adult rat hepatocytes were tested for their ability to glucuronize phenol red and to maintain
initial levels of cell proteins, glucose consumption, and lactic acid production. Lactate dehydrogenase leakage served as
an index of culture status because a high value indicates cell death. Three tissue culture (TC) media formulations were the
main variables introduced to determine ideal conditions for cell survival in vitro. Investigations of long-term cultures were
preceded by studies of hepatocyte attachment to polystyrene surfaces. This attachment was influenced by the amount of substrate
deposited and the number of cells seeded, but not by the uniformity of the substrate coating. A statistical analysis of our
data revealed that in the absence of fetal bovine serum (FBS), air dried collagen (ADC) and Biomatrix (BMX) were superior
to saline precipitated collagen and fibronectin as attachment substrates. In the presence of 10% FBS, all of the substrates
performed equally.
Chee's Medium (CEM) proved to be the best for preserving cell proteins over a time course of 28 d and Williams' E medium also
performed adequately up to 14 d. The glucuronization of phenol red was at 50% of initial values at Day 7 in CEM-ADC hepatocytes
in contrast to 30% for cells in Williams' E medium and 5% for cells grown in Waymouth's. At 14 d glucuronization was still
present at 40% of original values in CEM-ADC cells but had ceased in the other two media. When BMX was used, none of the TC
media supported glucuronization levels comparable to ADC cells.
This research was supported in part by grant 1R01-AM-26520 from the National Institute of Arthritis, Diabetes and Digestive
Kidney Diseases, NIH, Bethesda, Maryland. 相似文献
125.
C. J. Cao R. J. Mioduszewski D. E. Menking J. J. Valdes E. J. Katz M. E. Eldefrawi A. T. Eldefrawi 《In vitro cellular & developmental biology. Animal》1999,35(9):493-500
Summary Organophosphate (OP) anticholinesterases were found to modulate metabolic activities of human neuroblastoma cells and hepatocytes,
which was detectable by the Cytosensor? microphysiometer. The nerve gas ethyl-S-2-diisopropylaminoethyl methylphosphorothiolate (VX), at 10 μM, produced significant reduction in cell metabolism within 2 min, as measured by changes in the acidification rate of the
medium. The reduction was dose-and time-dependent and irreversible after 4 h of exposure. Two alkaline degradation products
of VX produced no cytotoxicity. Exposure for 24 h to 3 μM VX caused 36% and 94% irreversible loss of metabolism in hepatocytes and neuroblastoma cells, respectively. The insecticides
parathion and chlorpyrifos stimulated hepatocyte metabolism but inhibited neuroblastoma cells. Their oxons were more active.
Exposure of neuroblastoma cells for 4 h to VX, parathion, paraoxon, diisopropylfluorophosphate or chlorpyrifos gave an LC50 of 65, 775, 640, 340, or 672 μM, respectively, whereas 24 h gave an LC50 of 0.7, 3.7, 2.5, 29, and 31 μM, respectively. Preincubation of hepatocytes with phenobarbital enhanced their response to parathion and VX due to metabolic
bioactivation. Atropine partially blocked the effects of VX and paraoxon on both cell types, which suggests the involvement
of a muscarinic receptor as the target for cytotoxicity. There was no correlation between OP in vivo neurotoxicity and in
vitro cytotoxicity. It is suggested that the former results from their cholinesterase inhibition, while the latter results
from action on different targets and requires much higher concentrations. 相似文献
126.
Enhancement of optical coherence microscopy in turbid media by an optical parametric amplifier 下载免费PDF全文
Youbo Zhao Haohua Tu Yuan Liu Andrew J. Bower Stephen A. Boppart 《Journal of biophotonics》2015,8(6):512-521
We report the enhancement in imaging performance of a spectral‐domain optical coherence microscope (OCM) in turbid media by incorporating an optical parametric amplifier (OPA). The OPA provides a high level of optical gain to the sample arm, thereby improving the signal‐to‐noise ratio of the OCM by a factor of up to 15 dB. A unique nonlinear confocal gate is automatically formed in the OPA, which enables selective amplification of singly scattered (ballistic) photons against the multiply‐scattered light background. Simultaneous enhancement in both imaging depth and spatial resolution in imaging microstructures in highly light‐scattering media are demonstrated with the combined OPA‐OCM setup.
127.
128.
129.
Objective: To examine the phenomenon of fat stigmatization messages presented in television shows and movies, a content analysis was used to quantify and categorize fat‐specific commentary and humor. Research Methods and Procedures: Fat stigmatization vignettes were identified using a targeted sampling procedure, and 135 scenes were excised from movies and television shows. The material was coded by trained raters. Reliability indices were uniformly high for the seven categories (percentage agreement ranged from 0.90 to 0.98; kappas ranged from 0.66 to 0.94). Results: Results indicated that fat stigmatization commentary and fat humor were often verbal, directed toward another person, and often presented directly in the presence of the overweight target. Results also indicated that male characters were three times more likely to engage in fat stigmatization commentary or fat humor than female characters. Discussion: To our knowledge, these findings provide the first information regarding the specific gender, age, and types of fat stigmatization that occur frequently in movies and television shows. The stimuli should prove useful in future research examining the role of individual difference factors (e.g., BMI) in the reaction to viewing such vignettes. 相似文献
130.
Vijay C. Verma Surendra K. Gond Anuj Kumar Ravindra N. Kharwar Lori-Ann Boulanger Gary A. Strobel 《Indian journal of microbiology》2011,51(4):469-476
Azadirachta indica A. Juss. (neem), native to India, is well known worldwide for its insecticidal and ethanopharmacological properties. Although
endophytic microbes are known from this plant as only leaves and stems were the subjects of past reports. Now, a variety of
procedures and a number of different media were used to isolate the maximum number of endophytic fungi from unripe fruits
and roots. A total of 272 isolates of 29 filamentous fungal taxa were isolated at rate of 68.0% from 400 samples of three
different individual trees (at locations-Az1, Az2, Az3). Mycological agar (MCA) medium yielded the highest number of isolates
(95, with a 14.50% isolation rate) with the greatest species richness. Mycelia Sterilia (1, 2, 3) accounted for 11.06%, Coelomycetes
7.25%, while Hyphomycetes showed the maximum number of representative isolates (81.69%). Mycelia-Sterilia (1, 2, 3), based
on their 5.8S ITS 1, ITS2 and partial 18S and 28S rDNA sequences were identified as Fusarium solani (99%), Chaetomium globosum (93%) and Chaetomium globosum (93%) respectively. Humicola, Drechslera, Colletotrichum, and Scytalidium sp. were some of the peculiar fungal endophytes recovered from this plant. 相似文献