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81.
Steinmetz HW Kaumanns W Dix I Heistermann M Fox M Kaup FJ 《Journal of medical primatology》2006,35(1):3-11
BACKGROUND: Previous studies have characterized alopecia in captive rhesus macaques (Macaca mulatta) by a mixed partial to complete alopecia in a bilateral symmetric pattern. METHODS: In this study, coat condition assessments were related to exogenous and endogenous factors in captive rhesus macaques under different housing conditions in order to identify disturbances in environmental factors controlling or influencing hair growth. Additionally, the degree of alopecia was investigated in relation to adrenal endocrine function as an indicator of social stress using faecal glucocorticoid measurements. RESULTS: Hair loss was found to vary with season and sex, was most pronounced in adult females during the winter and spring months. Generally, infants were not affected, but alopecia developed during adolescence. However, the housing system, available enclosure space and variations in group size and composition also appeared to influence coat condition. Levels of immunoreactive cortisol metabolites (11-oxoetiocholanolone) in faeces were significantly negatively correlated with alopecia, suggesting a relationship between hypothalamic-pituitary-adrenal (HPA) axis activity and hair loss in captive rhesus macaques. CONCLUSIONS: Although the present study demonstrates the influence of the HPA axis on coat condition, it is not known if hair loss is caused by abnormal behaviour or hormonal imbalances of the HPA axis itself. Our data suggest that alopecia in rhesus macaques is a highly complex multicausal disorder. 相似文献
82.
83.
Blanchard V Liu X Eigel S Kaup M Rieck S Janciauskiene S Sandig V Marx U Walden P Tauber R Berger M 《Biotechnology and bioengineering》2011,108(9):2118-2128
Human alpha‐1‐antitrypsin (A1AT) is a protease inhibitor that is involved in the protection of lungs from neutrophil elastase enzyme that drastically modifies tissue functioning. The glycoprotein consists of 394 amino acids and is N‐glycosylated at Asn‐46, Asn‐83, and Asn‐247. A1AT deficiency is currently treated with A1AT that is purified from human serum. In view of therapeutic applications, rA1AT was produced using a novel human neuronal cell line (AGE1.HN®) and we investigated the N‐glycosylation pattern as well as the in vitro anti‐inflammatory activity of the recombinant glycoprotein. rA1AT (300 mg/L) was biologically active as analyzed using elastase assay. The N‐glycan pool, released by PNGase F digestion, was characterized using 2D‐HPLC, MALDI‐TOF mass spectrometry, and by exoglycosidase digestions. A total of 28 N‐glycan structures were identified, ranging from diantennary to tetraantennary complex‐type N‐glycans. Most of the N‐glycans were found to be (α1–6) core‐fucosylated and part of them contain the Lewis X epitope. The two major compounds are a monosialylated diantennary difucosylated glycan and a disialylated diantennary core‐fucosylated glycan, representing 25% and 18% of the total N‐glycan pool, respectively. Analysis of the site‐specificity revealed that Asn‐247 was mainly occupied by diantennary N‐glycans whereas Asn‐46 was occupied by di‐, and triantennary N‐glycans. Asn‐83 was exclusively occupied by sialylated tri‐ and tetraantennary N‐glycans. Next, we evaluated the anti‐inflammatory activity of rA1AT using A1AT purified from human serum as a reference. rA1AT was found to inhibit the production of TNF‐α in neutrophils and monocytes as commercial A1AT does. Biotechnol. Bioeng. 2011;108:2118–2128. © 2011 Wiley Periodicals, Inc. 相似文献
84.
Histone deacetylases (HDACs) are important epigenetic factors regulating a variety of vital cellular functions such as cell cycle progression, differentiation, cell migration, and apoptosis. Consequently, HDACs have emerged as promising targets for cancer therapy. The drugability of HDACs has been shown by the discovery of several structural classes of inhibitors (HDACis), particularly by the recent approval of two HDACis, vorinostat (ZOLINZA) and romidepsin (Istodax), for the treatment of cutaneous T-cell lymphoma by the US Food and Drug Administration. The outstanding potential of HDACis, with a defined isoform selectivity profile as drugs against a plurality of diseases, vindicates increased effort in developing high-throughput capable assays for screening campaigns. In this study, a dual-competition assay exploiting changes in fluorescence anisotropy and lifetime was used to screen the LOPAC (Sigma-Aldrich, St Louis, MO) library against the bacterial histone deacetylase homologue HDAH from Bordetella, which shares 35% identity with the second deacetylase domain of HDAC6. The binding assay proved to be highly suitable for high-throughput screening campaigns. Several LOPAC compounds have been identified to inhibit HDAH in the lower micromolar range. Most interestingly, some of the hit compounds turned out to be weak but selective inhibitors of human class IIa and IIb HDACs. 相似文献
85.
Several members of the CLCA family of proteins, originally named chloride channels, calcium-activated, have been shown to
modulate chloride conductance in various cell types via an unknown mechanism. Moreover, the human (h) hCLCA1 is thought to
modulate the severity of disease in asthma and cystic fibrosis (CF) patients. All CLCA proteins are post-translationally cleaved
into two subunits, and recently, a conserved HEXXH zinc-binding amino acid motif has been identified, suggesting a role for
CLCA proteins as metalloproteases. Here, we have characterized the cleavage and autoproteolytic activity of the murine model
protein mCLCA3, which represents the murine orthologue of human hCLCA1. Using crude membrane fractions from transfected HEK293
cells, we demonstrate that mCLCA3 cleavage is zinc-dependent and exclusively inhibited by cation-chelating metalloprotease
inhibitors. Cellular transport and secretion were not affected in response to a cleavage defect that was introduced by the
insertion of an E157Q mutation within the HEXXH motif of mCLCA3. Interspecies conservation of these key results was further
confirmed with the porcine (p) orthologue of hCLCA1 and mCLCA3, pCLCA1. Importantly, the mCLCA3E157Q mutant was cleaved after
co-transfection with the wild-type mCLCA3 in HEK293 cells, suggesting that an intermolecular autoproteolytic event takes place.
Edman degradation and MALDI-TOF-MS of the protein fragments identified a single cleavage site in mCLCA3 between amino acids
695 and 696. The data strongly suggest that secreted CLCA proteins have zinc-dependent autoproteolytic activity and that they
may cleave additional proteins. 相似文献
86.
87.
John H. Cardellina Demetrios Dalietos Franz-Josef Marner Jon S. Mynderse Richard E. Moore 《Phytochemistry》1978,17(12):2091-2095
(?)-trans-7(S)-Methoxytetradec-4-enoic acid and the related amides, malyngamides A, B and C, were found as constituents of shallow-water varieties of the marine blue-green alga Lyngbya majuscule. 相似文献
88.
89.
Martina Zöller Famke Aeffner Jochen Müller Kerstin Mätz-Rensing Franz-Josef Kaup 《European Journal of Wildlife Research》2008,54(1):15-20
Two cases of neoplasia occurred in two adult Siberian weasels (Mustela sibirica) in a game reserve in southern Lower Saxony, Germany. The first case, a male weasel, showed an enlargement of the right testicle,
which was surgically removed. The tumour was classified as an interstitial cell tumour. One year after surgery, the male weasel
died by accident and revealed tumour lesions of uncertain histogenesis within the abdominal cavity and the spleen at necropsy.
The second case, a female animal, became suspicious by a dermal mass in the upper left hind limb, which was also surgically
excised. Pathological examinations revealed a fibrosarcoma that recurred twice after removal of the original mass. These two
cases of neoplasia in the Siberian weasel are demonstrated with regard to clinical aspects and discussed on the basis of their
pathomorphological features. 相似文献
90.
Franz Zehetner Georg J. Lair Franz-Josef Maringer Martin H. Gerzabek Thomas Hein 《Biogeochemistry》2008,88(2):117-126
Substantial transformations of biogeochemical phosphorus (P) fractions can occur within a few hundreds of years under humid
and tropical conditions; however, slower changes are expected under dry and temperate climate. The objective of this study
was to infer P transformations over time by comparing suspended sediments in the Danube River to floodplain soils developed
from such sediments over different time periods in the continental climate of Central Europe. We analyzed suspended sediments
from 20 flood events between 1990 and 2006, and floodplain soils from seven sites along a chronosequence covering about 500 yrs.
The studied flood sediments had similar characteristics over the 16-yr observation period. Total phosphorus (TP) averaged
732 mg kg−1, and biogeochemical fractionation yielded important primary mineral contributions (apatite phosphorus, AP, ~80% of TP). The
TP concentrations of the floodplain soils were in the range of the Danube sediments and showed little variation along the
chronosequence. However, the distribution of P among biogeochemical fractions changed considerably in less than 500 yrs of
soil development. The youngest soils (<20 yrs) were dominated by AP, as was observed for the Danube sediments. In less than
250 yrs of pedogenesis, AP markedly decreased and organic phosphorus (OP) increased, and in less than 500 yrs, OP reached
AP levels. This shows that while P biogeochemistry in very young floodplain soils is strongly related to the river sediments,
significant transformations can occur in less than 250 yrs of soil development in the dry and temperate climate of Central
Europe. 相似文献