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991.
992.
Morphological features correlate with many life history traits and are therefore of high interest to behavioral and evolutionary biologists. Photogrammetry provides a useful tool to collect morphological data from species for which measurements are otherwise difficult to obtain. This method reduces disturbance and avoids capture stress. Using the Galapagos sea lion (Zalophus wollebaeki) as a model system, we tested the applicability of single-camera photogrammetry in combination with laser distance measurement to estimate morphological traits which may vary with an animal’s body position. We assessed whether linear morphological traits estimated by photogrammetry can be used to estimate body length and mass. We show that accurate estimates of body length (males: ±2.0%, females: ±2.6%) and reliable estimates of body mass are possible (males: ±6.8%, females: 14.5%). Furthermore, we developed correction factors that allow the use of animal photos that diverge somewhat from a flat-out position. The product of estimated body length and girth produced sufficiently reliable estimates of mass to categorize individuals into 10 kg-classes of body mass. Data of individuals repeatedly photographed within one season suggested relatively low measurement errors (body length: 2.9%, body mass: 8.1%). In order to develop accurate sex- and age-specific correction factors, a sufficient number of individuals from both sexes and from all desired age classes have to be captured for baseline measurements. Given proper validation, this method provides an excellent opportunity to collect morphological data for large numbers of individuals with minimal disturbance. 相似文献
993.
Horst Grunz Jochen Born Michael Davids Peter Hoppe Beate Loppnow-Blinde Lothar Tacke Heinz Tiedemann Hildegard Tiedemann 《Development genes and evolution》1989,198(1):8-13
Summary We have compared the chemical properties and biological activities of the mesoderm-inducing factor that is secreted by the Xenopus XTC cell line with the vegetalizing factor from chicken embryos. The inducing activity of the factors was tested in different concentrations on totipotent ectoderm either by implantation into early gastrulae of Triturm alpestris or by application of solutions to isolated ectoderm of early gastrulae of Xenopus laevis. Both factors have similar properties. They are not irreversibly inactivated after treatment with 6 M urea or with phenol at 60° C. Reduction with thioglycolic acid inactivates the factors completely. The inducing activity of XTC-conditioned medium decreases only slightly after treatment with 50% formic acid. The apparent molecular mass and the isoelectric point of the factors are similar. The XTC factor was partially purified by size-exclusion and reversed-phase high-pressure liquid chromatography and by isoelectric focusing. The possible relationship of these factors to transforming growth factor is discussed.Dedicated to Prof. Dr. Sulo Toivonen on the occasion of his 80th birthday 相似文献
994.
Dorit Schleinitz Nora Klöting Antje Körner Janin Berndt Marlene Reichenbächer Anke Tönjes Karen Ruschke Yvonne Böttcher Kerstin Dietrich Beate Enigk Matthias Filz Michael R. Schön Jost Jenkner Wieland Kiess Michael Stumvoll Matthias Blüher Peter Kovacs 《Obesity (Silver Spring, Md.)》2010,18(6):1218-1225
Inhibition of fatty acid synthase (FASN) induces a rapid decline in fat stores in mice, suggesting a role for this enzyme in energy homeostasis. To investigate the potential role of FASN in the pathophysiology of human obesity, the FASN gene was sequenced in 48 German whites. Thirty‐five single‐nucleotide polymorphisms (SNPs) were identified. Eight SNPs representative for their linkage disequilibrium groups and the Val1483Ile (rs2228305) substitution were genotyped for subsequent association analyses in 1,311 adults from Germany. Further, the tagging SNPs were genotyped also in German childhood cohorts (738 schoolchildren, 205 obese children). Effects of genetic variation on FASN mRNA expression in visceral and subcutaneous adipose tissue from a subgroup of 172 subjects were analyzed. Several polymorphisms in the FASN (rs62078748, rs2229422, rs2229425, and rs17848939) were nominally associated with obesity in case–control studies including 446 obese subjects (BMI ≥30 kg/m2) and 389 lean controls (BMI ≤25 kg/m2) (adjusted P < 0.05). The strongest significant effect was found for rs2229422 (P = 1.3 × 10?5 adjusted for age, sex, type 2 diabetes status), which was supported by associations with BMI, waist‐to‐hip ratio (WHR), fasting plasma insulin and glucose infusion rate (adjusted P < 0.05). Subjects with the Val1483Ile substitution appeared to be protected against obesity. In addition, rs17848939 was nominally significantly associated with the ratio of visceral/subcutaneous FASN mRNA expression (adjusted P = 0.04). No effect of genetic variation in FASN on obesity was found in children. In conclusion, our data indicate a role of FASN genetic variation in susceptibility to obesity in adults. 相似文献
995.
996.
Lucie Moeller Mario Grünberg Andreas Zehnsdorf Beate Strehlitz Thomas Bley 《Engineering in Life Science》2010,10(4):311-320
Our study aimed at the development of an effective method for citric acid production from glucose by use of the yeast Yarrowia lipolytica. The new method included an automated bioprocess control using a glucose biosensor. Several fermentation methodologies including batch, fed‐batch, repeated batch and repeated fed‐batch cultivation were tested. The best results were achieved during repeated fed‐batch cultivation: Within 3 days of cycle duration, approximately 100 g/L citric acid were produced. The yields reached values between 0.51 and 0.65 g/g and the selectivity of the bioprocess for citric acid was as high as 94%. Due to the elongation of the production phase of the bioprocess with growth‐decoupled citric acid production, and by operating the fermentation in cycles, an increase in citric acid production of 32% was achieved compared with simple batch fermentation. 相似文献
997.
998.
Diego Davila Paskulin Juliana Giacomazzi Maria Isabel Achatz Sandra Costa Rui Manoel Reis Pierre Hainaut Sidney Emanuel Batista dos Santos Patricia Ashton-Prolla 《PloS one》2015,10(11)
Rare germline mutations in TP53 (17p13.1) cause a highly penetrant predisposition to a specific spectrum of early cancers, defining the Li-Fraumeni Syndrome (LFS). A germline mutation at codon 337 (p.Arg337His, c1010G>A) is found in about 0.3% of the population of Southern Brazil. This mutation is associated with partially penetrant LFS traits and is found in the germline of patients with early cancers of the LFS spectrum unselected for familial history. To characterize the extended haplotypes carrying the mutation, we have genotyped 9 short tandem repeats on chromosome 17p in 12 trios of Brazilian p.Arg337His carriers. Results confirm that all share a common ancestor haplotype of Caucasian/Portuguese-Iberic origin, distant in about 72–84 generations (2000 years assuming a 25 years intergenerational distance) and thus pre-dating European migration to Brazil. So far, the founder p.Arg337His haplotype has not been detected outside Brazil, with the exception of two residents of Portugal, one of them of Brazilian origin. On the other hand, increased meiotic recombination in p.Arg337His carriers may account for higher than expected haplotype diversity. Further studies comparing haplotypes in populations of Brazil and of other areas of Portuguese migration are needed to understand the historical context of this mutation in Brazil. 相似文献
999.
Generation of cytokine-induced killer cells using exogenous interleukin-2, -7 or -12 总被引:22,自引:0,他引:22
Birgit Zoll Petja Lefterova Markus Csipai Sigrun Finke Beate Trojaneck Oliver Ebert Bettina Micka Klaus Roigk Matthias Fehlinger Gabriele D. Schmidt-Wolf Dieter Huhn Ingo G. H. Schmidt-Wolf 《Cancer immunology, immunotherapy : CII》1998,47(4):221-226
Immunologic effector cells termed cytokine-induced killer (CIK) cells are generated in vitro from peripheral blood lymphocytes
by addition of interferon-gamma, interleukin (IL)-2, IL-1 and an antibody against CD3. CIK cells have been shown to eradicate
established tumors in a SCID mouse/human lymphoma model. CIK cells are dependent on exogenous cytokines such as IL-2, IL-7,
or IL-12. We studied the effect of these cytokines in detail. Cellular proliferation was analyzed using an MTT proliferation
assay, surface antigen expression via flow cytometry, cytotoxic activity using an LDH release assay, and apoptosis via flow
cytometric analysis. IL-2, IL-7 and IL-12 led to significant growth of lymphocytes. Cells grown in IL-2 and IL-7 showed higher
proliferation rates than cells grown in IL-12 according to the MTT assay. Concerning surface antigen expression, exogenous
IL-7 led to a decrease in IL-7 receptor expression (4.8% from 60.4%) and exogenous IL-2 to a decrease in IL-2 receptor expression
(61.2% from 73.2%). CD28 expression was higher in cells grown in IL-7 (77.3%) than in cells grown in IL-2 (62.5%). IL-12 led
to a decrease in ICAM-1 adhesion molecule expression (57.7% from 76.7%) and an increase in CD56 expression compared with exogenous
IL-7. IL-7 led to higher number of CD4-positive cells than IL-2 (53.0% vs 49.5%). No significant difference was found between
IL-2, IL-7 and IL-12 in cytotoxic activity measured in an LDH release assay. Small amounts of apoptotic cells were found with
all cytokines. However, the percentage of necrotic cells was higher with exogenous IL-12 than with IL-2 or IL-7. In summary,
CIK cells can be generated using exogenous IL-2, IL-7 or IL-12. No difference in cytotoxic activity was found. However, significant
differences were found in cell proliferation rates, antigen expression and percentage of necrotic cells.
Received: 26 February 1998 / Accepted: 4 August 1998 相似文献
1000.
A Achilli L Iommarini A Olivieri M Pala B Hooshiar Kashani P Reynier C La Morgia ML Valentino R Liguori F Pizza P Barboni F Sadun AM De Negri M Zeviani H Dollfus A Moulignier G Ducos C Orssaud D Bonneau V Procaccio B Leo-Kottler S Fauser B Wissinger P Amati-Bonneau A Torroni V Carelli 《PloS one》2012,7(8):e42242