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41.
The clinical spectrum and treatment of Lyme disease 总被引:14,自引:0,他引:14
A C Steere S E Malawista N H Bartenhagen P N Spieler J H Newman D W Rahn G J Hutchinson J Green D R Snydman E Taylor 《The Yale journal of biology and medicine》1984,57(4):453-461
Lyme disease was recognized as a separate entity because of close geographic clustering of affected children in Lyme, Connecticut, with what was thought to be juvenile rheumatoid arthritis. It then became apparent that Lyme disease is a complex, multisystem disorder. The illness usually begins in summer with erythema chronicum migrans and associated symptoms (stage 1). Weeks to months later, some patients develop neurologic or cardiac abnormalities (stage 2), and weeks to years later, many patients develop intermittent attacks of arthritis (stage 3), which may become chronic, with erosion of cartilage and bone. Patients with severe and prolonged illness have an increased frequency of the B-cell alloantigen, DR2. For patients with early Lyme disease, tetracycline appears to be the most effective drug, then penicillin, and finally erythromycin. High-dose intravenous penicillin is effective for the later stages of the disease. 相似文献
42.
A survey of the genus Sorbaria (Rosaceae) 总被引:1,自引:0,他引:1
Knud Rahn 《Nordic Journal of Botany》1989,8(6):557-563
A taxonomic revision of the Asiatic genus Sorbaria (Rosaceae). 4 species are recognized: S. sorbifolia (including S. stellipila), S. grandiflora (= S. pallasii incl. S. rhoifolia), S. kirilowii,(incl. S. arborea and S. assurgens ) and S. tomentosa (= S. lindleyana , incl. S. olgae and S. gilgitensis ) with var. angustifolia , comb. nov. (= S. aitchisonii ). Hybrids presumably between S. sorbifolia and S. grandiflora and S. sorbifolia and S. kirilowii are found cultivated. 相似文献
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Influence of relative humidity on the photochemistry of DNA films 总被引:11,自引:0,他引:11
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Ten algal strains from snow and permafrost substrates were tested for their ability to produce secondary carotenoids and α-tocopherol in response to high light and decreased nitrogen levels. The Culture Collection of Cryophilic Algae at Fraunhofer IBMT in Potsdam served as the bioresource for this study. Eight of the strains belong to the Chlorophyceae and two strains are affiliated to the Trebouxiophyceae . While under low light, all 10 strains produced the normal spectrum of primary pigments known to be present in Chlorophyta, only the eight chlorophyceaen strains were able to synthesize secondary carotenoids under stress conditions, namely canthaxanthin, echinenone and astaxanthin; seven of them were also able to synthesize minor amounts of adonixanthin and an unidentified hydroxyechinenone. The two trebouxiophyceaen species of Raphidonema exhibited an unusually high pool of primary xanthophyll cycle pigments, possibly serving as a buffering reservoir against excessive irradiation. They also proved to be good α-tocopherol producers, which might also support the deactivation of reactive oxygen species. This study showed that some strains might be interesting novel candidates for biotechnological applications. Cold-adapted, snow and permafrost algae might serve as valuable production strains still exhibiting acceptable growth rates during the cold season in temperate regions. 相似文献
48.
Wieslander CK Rahn DD McIntire DD Acevedo JF Drewes PG Yanagisawa H Word RA 《Biology of reproduction》2009,80(3):407-414
Two mouse models of pelvic organ prolapse have been generated recently, both of which have null mutations in genes involved in elastic fiber synthesis and assembly (fibulin 5 and lysyl oxidase-like 1). Interestingly, although these mice exhibit elastinopathies early in life, pelvic organ prolapse does not develop until later in life. In this investigation we developed and validated a tool to quantify the severity of pelvic organ prolapse in mice, and we used this tool prospectively to study the role of fibulin 5, aging, and vaginal proteases in the development of pelvic organ prolapse. The results indicate that >90% of Fbln5(-/-) mice develop prolapse by 6 mo of age, even in the absence of vaginal delivery, and that increased vaginal protease activity precedes the development of prolapse. 相似文献
49.
A. Valdivieso-Garcia R. C. Clarke K. Rahn A. Durette D. L. MacLeod C. L. Gyles 《Applied microbiology》1993,59(6):1981-1983
A neutral red assay involving Vero cells was used to quantitate the cytotoxic activity of verotoxins (VT) produced by Escherichia coli and to investigate changes in titer caused by altering the composition of the cell culture medium. Three variations on medium 199 were investigated: one involved supplementing the medium with 5% fetal bovine serum (FBS), a second was the use of serum-free (SF) medium that contained 5% bovine serum albumin and 5 μg of fibronectin per ml, and the third involved the use of 4% Ultroser G, a commercial serum replacement. The level of cytotoxicity varied markedly with the type of VT and with the medium that was used. For VT1, there was no difference in cytotoxicity between medium with 5% FBS and SF medium, but cytotoxicity was reduced more than 100-fold in medium containing Ultroser G compared with cytotoxicity in the other media. For VT2, VT2v, and VTe, there was a slight reduction in cytotoxicity in medium containing 4% Ultroser G and a more marked reduction in SF medium compared with cytotoxicity in medium containing 5% FBS. 相似文献
50.
H Martin P Hufnagl M Beil K Wenzelides J Gottschalk W Rahn 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1992,14(4):312-319
Using a modified silver staining technique, we investigated nucleolar organizer region-associated proteins (AgNORs) in paraffin sections of 156 neoplastic tissues and other lesions, including gliomas (n = 41), meningiomas (n = 20), urinary bladder carcinomas (n = 58), and neoplastic and reactive lesions of the mesothelium of the pleural cavity (n = 37). We found significant differences in the mean number and area of AgNORs per nucleus between nonanaplastic and anaplastic astrocytomas. In meningiomas AgNOR analysis may be useful to distinguish between mostly benign tumors (grade 1 tumors) and atypical ones. Urinary bladder carcinomas exhibited a statistically significant increase in both AgNOR number and area as the grade of malignancy increased. Diagnostically useful differences in the AgNOR configuration between inflammatory and neoplastic processes were found for mesothelial lesions. In general, a higher grade of malignancy correlated with an increase in the AgNOR number. This was accompanied by an increase in the total AgNOR area per nucleus, irrespective of whether the size of the individual AgNORs had changed. 相似文献