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1.
Summary Quantitative electron microprobe analysis was employed to compare the effects of aldosterone and ADH on the intracellular electrolyte concentrations in the toad urinary bladder epithelium. The measurements were performed on thin freeze-dried cryosections utilizing energy dispersive x-ray microanalysis. After aldosterone, a statistically significant increase in the intracellular Na concentration was detectable in 8 out of 9 experiments. The mean Na concentration of granular cells increased from 8.9±1.3 to 13.2±2.2 mmol/kg wet wt. A significantly larger Na increase was observed after an equivalent stimulation of transepithelial Na transport by ADH. On average, the Na concentration in granular cells increased from 12.0±2.3 to 31.4±9.3 mmol/kg wet wt (5 experiments). We conclude from these results that aldosterone, in addition to its stimulatory effect on the apical Na influx, also exerts a stimulatory effect on the Na pump. Based on a significant reduction in the Cl concentration of granular cells, we discuss the possibility that the stimulation of the pump is mediated by an aldosterone-induced alkalinization.Similar though less pronounced concentration changes were observed in basal cells, suggesting that this cell type also participates in transepithelial Na transport. Measurements in mitochondria-rich cells provided no consistent results. 相似文献
2.
Adolf Češka 《Folia Geobotanica》1966,1(3):93-100
Various possibilities of usingSörensen's coefficient of floristic similarity in plant sociology are summarized. A new formula (11), derived from that bySörensen and based on constancy values, is suggested in order to calculate the mean floristic similarity within a set of relevés. 相似文献
3.
Adolf Češka 《Folia Geobotanica》1966,1(2):93-100
Various possibilities of usingSörensen’s coefficient of floristic similarity in plant sociology are summarized. A new formula (11). derived from that bySörensen and based on constancy values, is suggested in order to calculate the mean floristic similarity within a set of relevés. 相似文献
4.
Alchemilla austriaca is a new species which belongs to the group ofA. demissa, A. frigens, A. longana, A. longiuscula, A. semisecta, andA. sinuata. The holotype specimen as well as leaf and flower details are illustrated (Figs. 1–3). A complete character analysis is given, differences and similarities of allied species are presented in two tables, and the position of the group within the genus is discussed.A. austriaca so far is known only from the Austrian Alps and mainly from the central ranges (distribution map: Fig. 4). Its wet subalpine and alpine habitats are characterized by species lists. 相似文献
5.
Field trials on the effect of chlorocholinechloride (CCC) on rye plants of the cultivar Danae and of a selected population
“WRS” proved that rye principally shows as reaction analogous to wheat. The CCC-induced decrease of stalk length is due to
the reduction of elongation growth of the 4th internode. This shortening effect is mainly the result of decreased cell extension
and, in the middle internode, additionally of inhibited cell division in longitudinal direction. The shape of internodes is
changed under the influence of CCC. Walls of parenchyma cells of CCC-treated plants are thinner and those of sclerenchyma
cells are thicker compared with cell walls of control plants.
相似文献
6.
Natural human tumor necrosis factor beta (TNF-beta) purified from supernatants of a human B-lymphoblastoid cell line was found to be heterogeneous in molecular mass, with seven components resolved by gel electrophoresis. All components are N-glycosylated at Asn62; N-glycosylation does not contribute to heterogeneity. In addition, part of the molecules are O-glycosylated at Thr7; O-glycosylation is heterogeneous due to variable decoration with neuraminic acid. The four lower molecular mass forms are derived from the full-length protein by trypsin-like proteolytic cleavage in the N-proximal region; these clipped molecules lack O-linked carbohydrates. Two allelic variants differing in amino acid position 26 (threonine/asparagine) were identified. 相似文献
7.
G R Adolf B Frühbeis R Hauptmann I Kalsner I Maurer-Fogy E Ostermann E Patzelt R Schwendenwein W Sommergruber A Z?phel 《Biochimica et biophysica acta》1991,1089(2):167-174
A gene encoding human interferon omega-1 (IFN-omega 1) was isolated from a cosmid library, sequenced and expressed in Chinese hamster ovary (CHO) cells under the control of an SV40-derived promoter/enhancer sequence. Culture supernatants of stably transfected cell clones contained biologically active IFN-omega 1 at concentrations up to 10 micrograms/l. Amplification of the expression vector containing a dhfr gene under methotrexate selection pressure resulted in yields up to 200 micrograms/l. Production of IFN-omega 1 was further enhanced 2- to 3-fold by propagation of the cells in the presence of n-butyrate. IFN-omega 1 was purified from culture supernatants by monoclonal antibody affinity chromatography. The resulting protein was at least 95% pure as determined by reverse-phase HPLC and size-exclusion HPLC. Sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed two bands of about the same intensity with apparent molecular masses of 24.5 and 22.5 kDa. Upon treatment with peptide:N-glycosidase F, both bands were shifted to lower molecular masses (20.5 and 18.5 kDa), indicating that CHO cell-derived IFN-omega 1 is glycosylated; Asn-78 was identified as the glycosylation site. Analysis of the carbohydrate moiety using glycosidases and lectins revealed the presence of biantennary complex oligosaccharides containing neuraminic acid. Amino acid sequencing showed that only about 40% of the molecules have the expected N-terminus, whereas the others carry two additional amino acids derived from the signal sequence. C-terminal amino acid sequencing using carboxypeptidase P demonstrated that the smaller form of the protein lacks nine amino acids. Disulfide bridges were shown to connect Cys residues 1 and 99 as well as 29 and 139, respectively, as in IFN-alpha. The specific antiviral activity of recombinant, glycosylated human IFN-omega 1 on human cells was 2.6 x 10(8) IU/mg, not significantly different from that of the authentic, human leukocyte-derived protein. 相似文献
8.
9.
Katrin Bomans Antje Lang Veronika Roedl Lisa Adolf Kyrillos Kyriosoglou Katharina Diepold Gabriele Eberl Michael M?lh?j Ulrike Strauss Christian Schmalz Rudolf Vogel Dietmar Reusch Harald Wegele Michael Wiedmann Patrick Bulau 《PloS one》2013,8(11)
Biotherapeutics are often produced in non-human host cells like Escherichia coli, yeast, and various mammalian cell lines. A major focus of any therapeutic protein purification process is to reduce host cell proteins to an acceptable low level. In this study, various E. coli host cell proteins were identified at different purifications steps by HPLC fractionation, SDS-PAGE analysis, and tryptic peptide mapping combined with online liquid chromatography mass spectrometry (LC-MS). However, no host cell proteins could be verified by direct LC-MS analysis of final drug substance material. In contrast, the application of affinity enrichment chromatography prior to comprehensive LC-MS was adequate to identify several low abundant host cell proteins at the final drug substance level. Bacterial alkaline phosphatase (BAP) was identified as being the most abundant host cell protein at several purification steps. Thus, we firstly established two different assays for enzymatic and immunological BAP monitoring using the cobas® technology. By using this strategy we were able to demonstrate an almost complete removal of BAP enzymatic activity by the established therapeutic protein purification process. In summary, the impact of fermentation, purification, and formulation conditions on host cell protein removal and biological activity can be conducted by monitoring process-specific host cell proteins in a GMP-compatible and high-throughput (> 1000 samples/day) manner. 相似文献
10.
Clemens Röhrl Tamara A. Pagler Witta Strobl Adolf Ellinger Josef Neumüller Margit Pavelka Herbert Stangl Claudia Meisslitzer-Ruppitsch 《Histochemistry and cell biology》2010,133(3):261-272
Holo-high density lipoprotein (HDL) particle uptake, besides selective lipid uptake, constitutes an alternative pathway to
regulate cellular cholesterol homeostasis. In the current study, the cellular path of holo-HDL particles was investigated
in human liver carcinoma cells (HepG2) using combined light and electron microscopical methods. The apolipoprotein moiety
of HDL was visualized with different markers: horseradish peroxidase, colloidal gold and the fluorochrome Alexa568, used in fluorescence microscopy and after photooxidation correlatively at the ultrastructural level. Time course experiments
showed a rapid uptake of holo-HDL particles, an accumulation in endosomal compartments, with a plateau after 1–2 h of continuous
uptake, and a clearance 1–2 h upon replacement by unlabeled HDL. Correlative microscopy, using HDL-Alexa568-driven diaminobenzidine (DAB) photooxidation, identified the fluorescent organelles as DAB-positive multivesicular bodies
(MVBs) in the electron microscope; their luminal contents but not the internal vesicles were stained. Labeled MVBs increased
in numbers and changed shapes along with the duration of uptake, from polymorphic organelles with multiple surface domains
and differently shaped protrusions dominating at early times of uptake to compact bodies with mainly tubular appendices and
densely packed vesicles after later times. Differently shaped and labeled surface domains and appendices, as revealed by three
dimensional reconstructions, as well as images of homotypic fusions indicate the dynamics of the HDL-positive MVBs. Double
staining visualized by confocal microscopy, along with the electron microscopic data, shows that holo-HDL particles after
temporal storage in MVBs are only to a minor degree transported to lysosomes, which suggests that different mechanisms are
involved in cellular HDL clearance, including resecretion. 相似文献