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61.
Dr. J. Simpson 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1964,48(3):277-282
Summary Queens breathed continuously while they were piping, and were able to pipe with all spiracles except one blocked, so the sound could not have been produced by air entering or leaving the spiracles. It is produced by operating the flight motor without spreading the wings, and is radiated partly by the substratum, to which the vibrations are communicated by pressing the thorax against it.
Piping in English includes both tüten and quaken in German. Both sounds are produced in the same way but quaken is heard when the queen is in her cell (Armbruster, 1922). 相似文献
Zusammenfassung Königinnen atmeten während des Tütens ununterbrochen, und waren zum Tüten fähig, wenn alle Atemlöcher bis auf eines blockiert waren, so daß der Laut nicht durch Ein oder Austreten der Luft durch die Atemlöcher hervorgerufen sein konnte. Er wird erzeugt, indem der flight motor ohne das Ausbreiten der Flügel funktioniert, und teilweise durch das Substrat verbreitet, auf das die Schwingungen durch Anpressen des Thorax übertragen werden.
Piping in English includes both tüten and quaken in German. Both sounds are produced in the same way but quaken is heard when the queen is in her cell (Armbruster, 1922). 相似文献
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To demonstrate skeletal metastases before radiographic changes were apparent, Sr85 scans were carried out on 46 patients who complained of sketetal pain but whose radiographs were negative. Positive scans were obtained in 34 patients, 20 of whom were subsequently shown to have metastases; three did not have skeletal metastases a year or more later; the outcome is unknown in 11 patients. Twelve patients had negative scans: three ultimately developed metastases, six did not, and three were inconclusive. Autoradiographs demonstrated Sr85 concentrations in areas of reactive osteogenesis.Although not specific for skeletal metastases, Sr85 scans are most helpful in substantiating this diagnosis when radiographic changes are absent. 相似文献
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Telencephalic nucleus HVC and its two efferent targets, RA and X, play essential roles in the production of complex, learned vocalizations in the male zebra finch. Normal females do not produce these learned vocalizations; HVC, RA, and X are small in volume, and HVC and RA are not synaptically connected. We have shown that estrogen treatment during development causes females to learn and produce male-like vocalization. This article describes the neural masculinization of these E2 females, replicating and extending the work of others. Female zebra finches were treated with 17β-estradiol (E2) at hatching, at 14–22 days of age, or as adults. In adulthood, the volumes of nucleus RA and area X were measured and the efferent projections of nucleus HVC examined using the anterograde tracer PHA-L. Early, sustained E2 treatment caused the greatest increase in the volume of RA and X, the innervation of RA and X by HVC axons, and the masculinization of auditory responses of cells in RA. Treatments that lasted for a shorter period or started later in development resulted in different patterns of partial brain masculinization. E2 treatment in adulthood had no effect on the volume of RA or X or their innervation by HVC. Bilateral lesions of the tracheosyringeal nerves or of HVC had the same effects on the male-typical vocalizations produced by E2 females as they do on the vocalizations produced by males. These results demonstrate that the neural masculinization of telencephalic nuclei induced by E2 treatment sets up a functional circuit in females similar to one in males that enables the learning and production of complex vocalizations. 相似文献
66.
A survey was carried out to determine for the first time the extent of transplantation from living donors in the United Kingdom and Republic of Ireland and the views of transplant surgeons regarding future developments. Questionnaires were sent to 32 transplant centres representing 18 health regions and covered their extent of experience of transplantation, sources of donors, ages of donors and recipients, outcome of transplantation, and views on expansion of living donor transplantation services. Replies received from 27 transplant centres representing 17 health regions gave data on more than 1200 transplants from living donors. Transplants from living donors accounted for 0-25% of the total experience of health regions. Two centres had abandoned living donor transplantation. Sixty per cent of transplant surgeons favoured expansion of the living donor programme to meet a shortage of kidneys from cadavers, and the remainder thought that existing programmes were optimal. Living donor transplantation promises to be an important factor in the future planning of health care resources. 相似文献
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Identification of a common molecular basis for combined 17α-hydroxylase/17,20-lyase deficiency in two Mennonite families 总被引:1,自引:0,他引:1
Keiko Kagimoto Michael R. Waterman Masaaki Kagimoto P. Ferreira Evan R. Simpson Jeremy S. D. Winter 《Human genetics》1989,82(3):285-286
Summary During the course of studies to characterize mutations of the CYP17 gene that cause the 17-hydroxylase-deficient form of congenital adrenal hyperplasia we have discovered two ostensibly unrelated Mennonite families in which affected individuals are homozygous for the same mutation. The defect is a four-base duplication in exon 8 of the CYP17 gene, which alters the reading frame encoding the C-terminal 26 animo acids of cytochrome P45017. 相似文献
69.
T Yanase M Kagimoto S Suzuki K Hashiba E R Simpson M R Waterman 《The Journal of biological chemistry》1989,264(30):18076-18082
Steroid 17 alpha-hydroxylase and 17,20-lyase activities reside within the same polypeptide chain (cytochrome P-450(17 alpha)), and consequently human 17 alpha-hydroxylase deficiencies are characterized by defects in either or both of these activities. Human mutants having these deficiencies represent an excellent source of material for investigation of P-450(17 alpha) structure-function relationships. The CYP17 gene from an individual having partial combined 17 alpha-hydroxylase/17,20-lyase deficiency has been characterized structurally and the homozygous mutation found to be the deletion of the phenylalanine codon (TTC) at either amino acid position 53 or 54 in exon 1. Reconstruction of this mutation into a human P-450(17 alpha) cDNA followed by expression in COS 1 cells led to production of the same amount of immunodetectable P-450(17 alpha) protein as found with expression of the normal human P-450(17 alpha) cDNA. However, 17 alpha-hydroxylase activity of this mutant protein measured in intact cells was less than 37% of that observed upon expression of the wild-type enzyme, whereas 17,20-lyase activity of the mutant was less than 8% of that observed with the normal enzyme. When estimated in intact cells, the Km for 17 alpha-hydroxylation of progesterone was increased by a factor of 2 in the mutant enzyme, whereas the Vmax was reduced by a factor of 3. In order to estimate the kinetic parameters for the 17,20-lyase reaction, microsomes were isolated from transfected COS 1 cells to enrich for this activity. Surprisingly, the specific activity of the mutant 17 alpha-hydroxylase in microsomes was 3-fold less than that observed in intact cells, indicating that the structure of mutant P-450(17 alpha) was dramatically altered upon disruption of COS 1 cells. Apparently the deletion of a single phenylalanine in the N-terminal region of P-450(17 alpha) alters its folding in such a way that both enzymatic activities are dramatically decreased, leading to the partial combined deficiency observed in this individual. 相似文献
70.