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Physiological state influences the antennal response of Anastrepha obliqua to male and host volatiles 下载免费PDF全文
Humberto Reyes Edi A. Malo Jorge Toledo Samuel Cruz‐Esteban Julio C. Rojas 《Physiological Entomology》2017,42(1):17-25
The sexual and host‐related behaviours of the fruit fly Anastrepha obliqua Macquart (Diptera: Tephritidae) are mediated by volatile compounds. However, whether the physiological state of this species affects its antennal and behavioural responses to semiochemicals is unknown. The effects of age, mating status, diet and the topical application of methoprene, a Juvenile hormone analogue (JHA), on the antennal sensitivity of this tephritid fruit fly species to selected male [(Z)‐3‐nonenol] and host fruit volatiles (ethyl benzoate, ethyl hexanoate, ethyl butyrate and trans‐β‐ocimene) are investigated using electroantennography (EAG). Overall, (Z)‐3‐nonenol and ethyl benzoate elicit the highest EAG responses in both sexes. Flies of both sexes aged 1, 5 and 10 days old show higher EAG responses to the tested compounds compared with flies aged 20 days old. Virgin females and males show higher EAG responses to volatile compounds than mated flies. Females and males fed with sugar plus protein show higher antennal responses to volatiles compared with flies fed sugar or protein alone. Flies of both sexes treated with methoprene show higher antennal responses than flies treated with acetone (control). These results suggest that the peripheral olfactory system in A. obliqua is modulated by the physiological state of the flies. 相似文献
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Recombinant inbred strains of mice were used to localize the genes coding for the class alpha glutathione S-transferase 2 (Gst-2). The genes showed three distinct strain distribution patterns, indicating that they occur in at least three clusters separable by recombination. All three clusters are located in the vicinity of the d locus on mouse chromosome 9, but two of them are closer to d than the third. Linked to Gst-2 on mouse chromosome 9 are two enzyme-encoding loci, Pgm-3 and Mod-1. The human counterparts of Gst-2, Pgm-3, and Mod-1 map to 6p12, 6q12, and 6q12, respectively. Thus, the pericentric region of human chromosome 6 has its homolog in the segment spanning Gst-2, Pgm-3, and Mod-1 on mouse chromosome 9. The fact that the syntenic group extends across the centromere of human chromosome 6 can best be explained by a pericentric inversion postulated to have taken place in the primate lineage leading to Catarhini. 相似文献
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G Yarrington K Fontwit J P Figueroa A Massmann P W Nathanielsz 《The Yale journal of biology and medicine》1986,59(4):415-424
Cervical and uterine electromyograms (EMG) have been recorded from ovariectomized non-pregnant ewes. When the animals were infused with saline, the frequency of EMG events lasting less than 180 seconds was not different from those lasting more than 180 seconds. During infusion of estradiol at 100 micrograms X 24 hours-1 into the maternal jugular, the frequency of events less than 180 seconds increased significantly in the myometrium and in the cervix. Contracture activity (events lasting more than 180 seconds) was not significantly different in the myometrium compared to the cervix before estradiol administration. During estradiol infusion, the contracture activity remained unchanged. During 4-amino-antipyrine (4AA) administration, the contracture activity decreased significantly in the myometrium, while an insignificant change occurred in the cervix. This state was associated with a decrease in the venous PGFM:6-keto F1 alpha plasma ratio. Infusion of PGF2 alpha (.5 micrograms min-1 and 1.0 microgram X min-1 for ten minutes) into the femoral artery resulted in a significant increase in the frequency of events less than 180 seconds in both the myometrium and cervix. For the duration of the ten-minute infusion, the activity was contracture-like. These findings suggest that the cervix may not only be influenced by mechanical properties (stretch) and local paracrine factors but also by various stimulators and inhibitors irrespective of the myometrium. 相似文献
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Felipe Couñago Ana Aurora Díaz Gavela Gemma Sancho Irene Ortiz Francisco José Marcos Manuel Recio Julio Fernández Raquel Cano Mar Jiménez Israel J. Thuissard David Sanz-Rosa Juan Castro Nováis Eduardo Pardo Yolanda Molina Hugo Pérez García Elia del Cerro 《Reports of Practical Oncology and Radiotherapy》2019,24(5):472-480
AimTo analyse the efficacy and toxicity of postprostatectomy SRT in patients with a BCR evaluated with mpMRI.BackgroundMultiparametric magnetic resonance imaging (mpMRI) has the ability to detect the site of pelvic recurrence in patients with biochemical recurrence (BCR) after radical prostatectomy (RP). However, we do not know the oncological outcomes of mpMRI-guided savage radiotherapy (SRT).ResultsLocal, lymph node, and pelvic bone recurrence was observed in 13, 4 and 2 patients, respectively. PSA levels were significantly lower in patients with negative mpMRI (0.4 ng/mL [0.4]) vs. positive mpMRI (2.2 ng/mL [4.1], p = 0.003). Median planning target volume doses in patients with visible vs. non-visible recurrences were 76 Gy vs. 70 Gy. Overall, mean follow-up was 41 months (6–81). Biochemical relapse-free survival (bRFS) at 3 years was 82.3% and 82.5%, respectively, for the negative and positive mpMRI groups (p = 0.800). Three-year rates of late grade ≥2 urinary and rectal toxicity were 14.8% and 1.9%, respectively; all but one patient recovered without sequelae.ConclusionSRT to the macroscopic recurrence identified by mpMRI is a feasible and well-tolerated option. In this study, there were no differences in bRFS between MRI-positive and MRI-negative patients, indicating effective targeting of MRI-positive lesions. 相似文献
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Lau Yan Ng Julio C.Y. Liu Xiner Huang Nelson Lee Randy Y.C. Poon 《Cell cycle (Georgetown, Tex.)》2019,18(2):238-248
Characterizing the functions of essential cell cycle control genes requires tight and rapid inducible gene inactivation. Drawbacks of current conditional depletion approaches include slow responses and incomplete depletion. We demonstrated that by integrating the tetracycline-controlled promoter system and the auxin-inducible degron (AID) system together, AID-tagged proteins can be downregulated more efficiently than the individual technology alone. When used in conjunction with CRISPR-Cas9-mediated disruption of the endogenous locus, this system facilitates the analysis of essential genes by allowing rapid and tight conditional depletion, as we have demonstrated using several cell cycle-regulatory genes including cyclin A, CDK2, and TRIP13. The vectors constructed in this study allow expression of AID-fusion proteins under the control of tetracycline-controlled promoters and should be useful in studies requiring rapid and tight suppression of gene expression in mammalian cells. 相似文献