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91.
F. X. Côte C. Teisson X. Perrier 《In vitro cellular & developmental biology. Plant》2001,37(5):539-542
Summary In order to better understand somaclonal variant rate evolution in plant tissue culture, a statistical approach has been adopted.
According to this approach, the variant percentage could be calculated by: %V=[1−(1−p)
n
]×100, where %V is the percentage of variant, p the probability of variation and n the number of multiplication cycles. A numerical estimation was performed to characterize the variance of this function.
It has been demonstrated that a wide scale of variance is associated with ‘%V’, due to the occurrence of variations after
a variable number of multiplication cycles in the different lines of culture. Two main conclusions can be drawn from this
model: (1) a variant rate increase can be expected as an exponential function of the number of multiplication cycles; (2)
after a given number of multiplication cycles, variable off-types percentages can be expected. Due to the complexity of biological
systems, this statistical approach could obviously not be applied directly for the calculation and forecasting of variant
rates in tissue culture. However, this approach results in a better understanding of two apparently confusing experimental
features often reported in tissue culture: the increase of the variant rate as a function of the length of the culture period
on the one hand, and, on the other hand, the observations of different variant rates among lines cultured for the same lengths
of time under strietly identical culture conditions. This approach also underlined that the comparison of somaclonal variant
percentage between batches of plants from different in vitro treatments could be, in some cases, insufficient for ascertaining a difference of variability generated by tissue culture. 相似文献
92.
Rajasri Bhattacharyya Sabita Bhattacharya 《In vitro cellular & developmental biology. Plant》2001,37(5):572-575
Summary A protocol has been developed that leads to the development of complete plantlets of Coleus forskohlii within 35–40 d by culturing stem tip explants in MS medium containing 0.57 μM indole-3-acetic acid and 0.46 μM kinetin through direct multiplication at the rate of 12.5 shoots per explant. About 100% shoots rooted and micropropagated
plants were successfully established in soil after hardening with a high survival rate. The significance of the present micropropagation
protocol of C. forskohlii is the formulation of growth regulators which effected very fast multiplication of the plant (time reduced to one-third of
the hitherto known methods). 相似文献
93.
AbstractIn the present work, we have used copper sulphate (CuSO4·5H2O) enriched medium for effective control of visible and latent contamination. Among the different concentrations used, 1.25–2.5?mg/L resulted the most appropriate. In addition, the role of different nitrogen source and concentrations (NH4NO3 and KNO3), as different iron source (FeEDTA and FeEDDHA) has been investigated in the proliferation and rooting phases of European hazelnut (cv. Tonda Gentile Romana). The normal concentration of nitrogen present in Murashige and Skoog medium is too high for hazelnut micropropagation cv. Tonda Gentile Romana. A reduction of total nitrogen, accompanied by a reduction of ammonium forms, resulted in a better quality of the shoots. Similar results have been obtained when the common iron source FeEDTA has been replaced by the same concentration of FeEDDHA. An increase in rooting occurs when the amount of nitrogen was reduced in the rooting medium, particularly when the NH4NO3 was not present. 相似文献
94.
Towards automation: Radiata pine shoot hedges in vitro 总被引:3,自引:0,他引:3
A novel system for in vitro shoot production has been developed whereby shoot hedges are maintained in one vessel. Monthly crops of shoots are produced for rooting. Radiata pine shoot hedges were maintained on Lepoivre (LP) nutrient agar medium for 18 months using a weekly liquid-nutrient replenishment system. In a separate experiment liquid-LP-nutrient replenishment of shoots twice weekly without transfers (D) resulted in better shoot growth and health than monthly transfers to fresh agar medium (B), monthly transfers to fresh agar medium plus aeration twice weekly (C), or no transfers and no liquid nutrient addition (A). Liquid nutrient replenishment twice weekly was better than 2 weekly or 4 weekly replenishment. The percentage of normal waxy (abundant tubular epicuticular wax) shoots harvested monthly increased significantly over the culture period from 41% at the first harvest to 93% at the eight harvest, and remained high at 97% from the ninth to twelfth harvest. The percentage of wet (no tubular epicuticular wax, small amounts of globular epicuticular wax) shoots harvested showed a corresponding decline—from 59%, to 7% at the eighth harvest. Shoots were harvested at a rate of 672/h (1.19 cents/shoot at a labour cost of NZ$8.00/h) and approximately 1100 shoots were produced per square metre of agar surface per month. Initial problems of contamination and crowding were overcome. These results will greatly facilitate progress towards automation of shoot production and reduction of costs of micropropagated trees. An automated system used in combination with other cost-saving techniques or robotics could potentially result in a substantial reduction in costs. This is the first report of a method of culturing shoots as hedges for a period of up to 18 months without manual subculturing. 相似文献
95.
Mohanjeet S. Brar Misty J. Moore Jameel M. Al-Khayri Teddy E. Morelock Edwin J. Anderson 《In vitro cellular & developmental biology. Plant》1999,35(3):222-225
Summary Ethylene is a plant growth regulator that is known to influence in vitro morphogenesis. This study investigated the effects
of three ethylene inhibitors, silver nitrate (AgNO3), 2,5-norbornadiene, and cobalt chloride (CoCl2), on the regeneration of cowpea from cotyledon explants. Significant increases in the percentage of regeneration occurred
as a result of adding either 50 μM AgNO3 or 100 μM 2,5-norbornadiene. The number of shoots produced per explant was enhanced by adding 25 μM CoCl2 or 100 μM norbornadiene. Maximum shoot elongation was obtained with 25 μM of either CoCl2 or norbornadiene. The effect of the duration of exposure to AgNO3 was also determined. The greatest percent regeneration was obtained with the addition of 60 μM AgNO3 either to both the initiation and regeneration stages, or to only the regeneration stage. The promotive effects on organogenesis
in response to ethylene inhibitors suggests an important role for ethylene in the process of in vitro morphogenesis of cowpea
and may contribute to its normally low regeneration frequency. 相似文献
96.
Meira Ziv 《In vitro cellular & developmental biology. Plant》1991,27(2):64-69
Summary Vitrification-Hyperhydrous shoot development, effects the survival and quality of several micropropagated plants ex-vitro.
The leaves which are the immediate organ to be affected, exhibit abnormal morphology and physiology. Leaf malfunction is apparently
a stress response to very rich media and high relative humidity. The understanding of the underlying mechanism of vitrification
and its control in vitro can contribute to a more efficient micropropagation. Vitrification was found to be associated with
elevated ethylene production which was related to hypolignification and poor cell wall development. Liquid and low agar media
induced callose formation along with reduced and disoriented cellulose biosynthesis, manifested also in non-functioning guard
cells. Malfunctioning stomata, in addition to defective cuticle contributed to increased transpiration and desiccation of
in vitro formed leaves. The activity of various enzymes, associated with cell wall synthesis, was low and total proteins in
normal leaves was higher than in vitreous ones. Various measures were found to reduce vitrification; lowered matrix and water
potential in the medium, reduction in RH, low NH
4
+
, changes in Ca++ levels and the removal of ethylene. These measures improved leaf morphogenesis, survival and the quality of several micropropagated
plant species.
Presented in the Session-in-Depth Transition of Plants From Culture to Establishment In Vivo,“ at the 41st Annual Meeting
of the Tissue Culture Association, Houston, Texas, June 10–13, 1990. 相似文献
97.
An increase of the vapor pressure deficit (VPD) of the growth room atmosphere (from 600 Pa up to 2000 Pa) induced a variation in the air VPD inside the vessels used for rose micropropagation.During the photoperiod, the in vitro plants lost water by evaporation. During the night period, depending upon the VPD of the growth room, plants could take water from the vessel atmosphere.According to the intensity of the transpiration, large changes in the growth and morphology were observed: decrease in multiplication rate, modification of leaf colour and area, reduction of the elongation and changes of the level of axillary buds which grew. 相似文献
98.
Plant regeneration of Mangifera indica using liquid shaker culture to reduce phenolic exudation 总被引:3,自引:0,他引:3
The exudation of phenolics from the cut ends of mango explants greatly hinders their regenerative ability in any in vitro growth medium. However, pretreatment of explants using liquid shaker culture helps in overcoming this problem. Explants kept in liquid MS medium supplemented with 1% polyvinylpyrolidone in 250 ml conical flasks on an automated shaker at 75 rpm were able to produce shoots when inoculated on gelled MS medium supplemented with different concentrations of growth regulators.Abbreviations BA
benzyladenine
- IAA
indoleacetic acid
- NAA
naphthaleneacetic acid
- IBA
indolebutyric acid 相似文献
99.
Studies on lead and cadmium toxicity in Dianthus carthusianorum calamine ecotype cultivated in vitro 下载免费PDF全文
- Information on metallophytes during reclamation of land contaminated with heavy metals is sparse. We investigated the response of D. carthusianorum calamine ecotype to Pb and Cd stress. We focused on in vitro selection of tolerant plant material for direct use in chemically degraded areas.
- Shoot cultures were treated with various concentrations of Pb or Cd ions. Plantlet status was estimated as micropropagation efficiency, growth tolerance index (GTI) and through physiological analysis. Moreover, determination of plant Pb, Cd and other elements was performed.
- The application of Pb(NO3)2 resulted in stronger growth inhibition than application of CdCl2. In the presence of Pb ions, a reduction was observed of both, the micropropagation coefficient to 1.1–1.8 and the GTI to 48%. In contrast, Cd ions had a positive influence on tested cultures, expressed as an increase of GTI up to 243% on medium enriched with 1.0 μm CdCl2. Moreover, photosynthetic pigment content in shoots cultivated on media with CdCl2 was higher than in control treatment. The adaptation to Cd was associated with decreased accumulation of phenols in the order: 0.0 μm > 1.0 μm > 3.0 μm > 5.5 μm CdCl2. It seems that high tolerance to Cd is related to K uptake, which is involved in antioxidant defence.
- This work presents an innovative approach to the impact of Cd ions on plant growth and suggests a potential biological role of this metal in species from metalliferous areas.
100.
Midrib sections of Mussaenda 'Queen Sirikit', 'Do?a Luz', and 'Do?a Hilaria' were cultured on Murashige and Skoog medium (MS) supplemented with 87.7 mM
sucrose, 5 g agar l−1, 0, 5, 10 or 20 μM indole-3-acetic acid (IAA) and 0, 0.5, 1, 2.5, 5, 10, 25 or 50 μM 6-benzyladenine (BA). In addition, aseptic
5 mm shoot tips from 'Do?a Luz' cultures were excised and cultured on MS basal salts, 0.6 mM myo-inositol, 1.2 μM thiamine-HCl,
87.7 mM sucrose, 7 g agar l−1, 0, 2.5, 5, 10, 20, or 40 μM BA, 0 or 1 μM α-naphthaleneacetic acid (NAA) and 0 or 217 μM adenine sulfate at pH 5.8. Calluses
began to develop after two weeks at the cut ends of midribs when cultured on a medium containing IAA. Somatic embryos first
appeared at eight weeks but only on 'Queen Sirikit' callus. After 15 weeks, the average number of somatic embryos produced
per tube decreased as the IAA concentration increased from 0 to 20 μM. BA concentrations between 5.0 and 10.0 μM resulted
in the largest number of somatic embryos per tube. After six weeks, the total, axillary and adventitious number of 'Do?a Luz'
shoots increased as the BA concentration in the culture medium increased from 0 to 20 μM. Average shoot length and fresh weight
decreased from 0 to 40 μM BA. The addition of NAA to the culture medium reduced shoot number. Adenine sulfate in the presence
of BA reduced the total number of shoots. An ideal medium for proliferating the largest number of 'Do?a Luz' shoots would
be a MS medium supplemented with 10–20 μM BA.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献