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Nigel F. Mathers 《Biochemical Systematics and Ecology》1975,3(3):123-127
Two geographically and reproductively isolated populations each of Chlamys opercularis and of Chlamys varia are compared with respect to polymorphism at the phosphoglucose isomerase (PGI) locus. One population of C. varia is further sub-divided into sub-littoral and inter-tidal samples. From the results it is inferred that PGI is a dimeric molecule, controlled by five alleles in C. varia and by at least four alleles in C. opercularis. acting at a single locus. The alleles recognised for C. opercularis have identical electrophoretic mobility as four of those seen in C. varia. The two populations of C. varia are remarkably similar, as were their habitats. However, the sub-littoral sample does show a lesser degree of homozygosity than the inter-tidal sample of the same population. The two populations of C. opercularis differ significantly and represent two separate and identifiable ‘races’. C. varia exhibits a much greater degree of genetic variability than the deep sub-littoral species, C. opercularis indicating that a more stable environment regulates a more monomorphic species. 相似文献
174.
N. Mathers M. Bramley K. Draper S. Snead A. Tobert 《BMJ (Clinical research ed.)》1994,308(6934):969-972
The Institute of Psychosexual Medicine offers training in the treatment of psychosexual problems to medically qualified doctors. Training takes place in fortnightly seminars in which trainees present and discuss real cases. Assessment of cases presented at the beginning and end of the six term basic training showed appreciable improvement in doctors'' abilities. The proportion of doctors meeting each of the 14 predetermined clinical objectives rose. Factors which affected the amount of improvement were the initial score, the number of cases presented at the seminars, the occupation of the leader, and the duration of training. Accreditation by the Institute of Psychosexual Medicine was shown to be an appropriate outcome measure for the achievement of the required standards for practising psychosexual medicine. 相似文献
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Daniel G. Thornham Catherine Stamp Keith F.A. Walters James J. Mathers Maureen Wakefield Alison Blackwell 《Biocontrol Science and Technology》2007,17(10):983-994
The behavioural responses previously reported from Coccinella septempunctata to the organophosphate, dimethoate, have implications for the effective development of integrated pest management (IPM) strategies. Through a series of simple tests, coccinellids’ consumption rates were measured from live pesticide-resistant aphids, treated with five insecticides from three chemical classes: carbamates, organophosphates and pyrethroids. This study quantifies for the first time the doses of ingested insecticide to which C. septempunctata responds, and demonstrates that a number of insecticides can cause C. septempunctata to change its feeding behaviour. Females were confirmed to eat more than males, and responses to insecticides were observed more frequently in females. Aphid consumption was reduced most in the pyrethroid treatment groups, but choice tests found no preference for either treated or untreated prey in any group. The results are discussed in terms of the mechanism by which coccinellids detect insecticides, and the consequences for IPM. 相似文献
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Grenville Mathers 《BMJ (Clinical research ed.)》1943,1(4297):614-615
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BM Madison 《Biotechnic & histochemistry》2001,76(3):119-125
Stains have been used for diagnosing infectious diseases since the late 1800s. The Gram stain remains the most commonly used stain because it detects and differentiates a wide range of pathogens. The next most commonly used diagnostic technique is acid-fast staining that is used primarily to detect Mycobacterium tuberculosis and other severe infections. Many infectious agents grow slowly on culture media or may not grow at all; stains may be the only method to detect these organisms in clinical specimens. In the hands of experienced clinical microscopists, stains provide rapid and cost-effective information for preliminary diagnosis of infectious diseases. A review of the most common staining methods used in the clinical microbiology laboratory is presented here. 相似文献
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