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921.
Yuhsi Matuq Pamela S. Adams Nozomu Nishi Hidetaro Yasumitsu John W. Crabb Robert J. Matusik Wallace L. McKeehan 《In vitro cellular & developmental biology. Plant》1989,25(6):581-584
Summary Rat prostate extracts contain an abundant 20–22 kilodalton heparin-binding protein with near identical chromatographic properties,
but only 0.2–1% of the mitogenic activity, of bovine brain heparin-binding growth factor-1 (acidic fibroblast growth factor).
Amino terminal amino acid sequence (met-met-thr-asp-lys-asn-leu-lys-lys-lys-ile-glu-gly-asn-trp-arg-thr-val-tyr-leu-ala-ala-ser-?-val-glu-lys-ile-asn-glu-gly-ser-pro)
and immunochemical analysis revealed that the protein is identical to the androgen-dependent protein “probasin”.
This work was supported in part by NCI grant CA37589 (W. L. M., J. W. C.) and the Medical Research Council of Canada (R. J.
M.). 相似文献
922.
Ilse P. Munyon John F. Hubstenberger Greory C. Phillips 《In vitro cellular & developmental biology. Plant》1989,25(3):293-296
Summary Androgenesis occurred from chile pepper (Capsicum annuum L.) anthers incubated in a continuous warm environment (29° C) with continuous light. Forty plantes and embryoids were retrieved
from anther cultures and anllyzed for isozyme markers. Of these, 35 exhibited a single allele for markers suggesting microspore
origin, while 5 were heterozygous indicating somatic tissue origin. Chromosome numbers were confirmed for 21 plantlets, of
which 16 were haploid and 5 were diploid. However, two plants exhibited a single allele for an isozyme marker but possessed
the diploid chromosome number, suggesting spontaneous doubling. Anther cultures also produced callus. Nearly 92% of the slow-growing
calli sampled were heterozygous for the isozyme marker, suggesting somatic tissue origin. More than 46% of the fast-growing
calli exhibited only one allele for the marker, indicating microspore origin. Callus did not regenerate plantlets. The occurrence
of both heterozygous and homozygous diploid plantlets from pepper anther cultures has important implications for applied breeding
programs. 相似文献
923.
A simple,rapid protocol for adventitious shoot development from mature cotyledons of glycine max cv bragg 总被引:5,自引:0,他引:5
Seth Mante Ralph Scorza John Cordts 《In vitro cellular & developmental biology. Plant》1989,25(4):385-388
Mature soybean cotyledons (Maturity group VII) were cultured on modified MS containing 0–2.5 μM indole-butyric acid (IBA);
0–10 μM 6-benzylaminopurine (BAP) and 0.7% agar. Embryonic axes of explants were removed prior to culture initiation and cultures
were incubated at 24°C with 45–50 μE. s−1.M−2 of mixed irradiance with 16 h photoperiod. Shoot proliferation occurred at 0–2.5 μM IBA and 5–10 μM BAP, while in the presence
of 2.5 μM IBA alone, only roots developed. Abnormal shoots were produced with 2.5 μM IBA and 5–7.5 μM thidiazuron. Adventitious
shoot development started 7–14 d after culture initiation in the region where the embryonic axis was previously attached to
the cotyledon and shoots were visible within 28 days. The presence of the embryonic axis inhibited shoot morphogenesis. The
shoots were rooted on half strength MS inorganic salts plus vitamins, 2% sucrose, 0.5 μM NAA acid or 2.5–5 μM IBA, or 5–10
μM IAA, and 0.7% agar. Rooted plants were acclimatized under a mist in the greenhouse. This simple, rapid,in vitro adventitious shoot development protocol could be adapted for transformation/regeneration studies in soybean.
Trade and company names are used in the publication solely to provide specific information. Mention of a trade or company
name does not constitute a warranty or an endorsement by the U.S. Department of Agriculture to the exclusion of other products
or organizations not mentioned. 相似文献
924.
925.
K. Lynette Pearce Dr. Bernard T. Engel John R. Burton 《Applied psychophysiology and biofeedback》1989,14(3):207-217
Fifteen hypertensive patients were recruited from a geriatric medicine clinic for a research project designed to evaluate a Behavioral Stepped-Care treatment program of high blood pressure (HBP). All patients met the selection criteria of the Isolated Systolic Hypertension (ISH) in the Elderly (SHEP) clinical trial. During baseline, subjects recorded BP at home 9 times/day (3 times each, shortly after awakening, during the middle of the day, and within an hour of retiring) for 1 month and mailed that data to us daily. In addition, they came to the clinic weekly and had their BP recorded by a nurse. During treatment 1, systolic (SBP) feedback, they were trained to lower SBP at home using their sphygmomanometers. They also continued to monitor BP and to obtain weekly professional BP readings. During treatment 2 (relaxation), they were trained to relax; they followed the self-administration and data-collection protocol as in treatment 1. Each treatment phase lasted 3 months. Average monthly self-determined BP fell significantly from 166.4/85.8 (SBP/DBP) mm Hg during baseline to 153.3/81.2 by the end of the relaxation phase; average monthly professionally measured BP fell significantly, from 164.7/87.1 to 156.9/81.5. These findings show that a nurse-supervised, patient-administered behavioral treatment program of ISH can yield sustained, significant falls in BP.Ms. Pearce and Dr. Burton were supported in part by the Johns Hopkins Academic Nursing Home Award, PO, AG04402, from the National Institute on Aging. This material was presented in part at the annual meeting of the Gerontological Society of America, November 1988, San Francisco. 相似文献
926.
927.
Image analysis of restriction enzyme fingerprint autoradiograms 总被引:6,自引:0,他引:6
Sulston John; Mallett Frank; Durbin Richard; Horsnell Terry 《Bioinformatics (Oxford, England)》1989,5(2):101-106
A genome mapping system has been developed that reads and assemblesdata from clones analysed by restriction enzyme fragmentationand polyacrylamide gel electrophoresis. Input data for the systemcan be most effectively obtained by the use of a scanning densitometerand image-processing package, such as that described in thisarticle. The image-processing procedure involves preliminarylocation of bands, cooperative tracking of lanes by correlationof adjacent bands, a precise densitometric pass, alignment ofthe marker bands with the standard, optional interactive editing,and normalization of the accepted bands.
Received on August 31, 1988; accepted on December 6, 1988 相似文献
928.
929.
Huang Q.; Zhou D.; St John W. M.; Bartlett D. Jr 《Journal of applied physiology》1989,67(3):1179-1184
To investigate the influence of inspiratory lung inflation on the respiratory activities of laryngeal motor nerves, vagally intact decerebrate paralyzed cats were ventilated by a servorespirator in accordance with their own phrenic nerve activity. Records were made of the activities of the phrenic nerve, the superior laryngeal nerve (SLN), the recurrent laryngeal nerve (RLN), and the intralaryngeal branches of the RLN serving the thyroarytenoid (TA) and posterior cricoarytenoid (PCA) muscles. Neural activities were assessed in the steady state at different end-tidal O2 and CO2 concentrations. Transient responses to withholding inspiratory lung inflation and to preventing expiratory lung emptying were also studied. Hypercapnia and hypoxia increased the inspiratory activities of the phrenic nerve, SLN, RLN, and its PCA branch. TA inspiratory activity was not changed. Expiratory activities of RLN, PCA, and TA were all increased in hypoxia. When lung inflation was withheld, neural inspiratory duration and the inspiratory activities of all nerves increased. The subsequent period of neural expiration was marked by an exaggerated burst of activity by the TA branch of the RLN. TA expiratory activity was also sharply increased after inspiratory efforts that were reflexly delayed by the prevention of lung emptying. TA activity in expiration was enhanced after vagotomy and was usually more prominent than when lung inflation was withheld before vagal section. The results demonstrate the importance and complexity of the influence of vagal afferents on laryngeal motor activity. 相似文献
930.
Zhou D.; Huang Q.; St John W. M.; Bartlett D. Jr 《Journal of applied physiology》1989,67(3):1171-1178
To distinguish experimentally between motor nerve activity destined for vocal cord abductor muscles and that bound for muscles that adduct the cords, we recorded efferent activities of intralaryngeal branches of the recurrent laryngeal nerve (RLN) in decerebrate, vagotomized, paralyzed, ventilated cats. Activities of the whole RLN and phrenic nerve were also recorded. Nerve activities were assessed at several steady-state end-tidal O2 and CO2 concentrations. The nerve to the thyroarytenoid (TA) muscle, a vocal cord adductor, was only slightly active under base-line (normocapnic, hyperoxic) conditions but in most cats developed strong activity during expiration in hypocapnia or hypoxia. In severe hypocapnia, phasic expiratory TA activity persisted even during phrenic apnea, indicating continuing activity of the respiratory rhythm generator. The nerve to the posterior cricoarytenoid (PCA) muscle, the vocal cord abductor, was always active in inspiration but often showed expiratory activity as well. This expiratory activity was usually enhanced by hypercapnia and often inhibited by hypoxia. The results are consistent with previous electromyographic findings and emphasize the importance of distinguishing abductor from adductor activity in studies of laryngeal control. 相似文献