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41.
Light-microscopic histochemistry of non-specific alkaline phosphatase using lanthanide-citrate complexes 总被引:1,自引:0,他引:1
K. -J. Halbhuber R. Gossrau U. Möller N. Zimmermann 《Histochemistry and cell biology》1988,90(1):67-72
Summary New lanthanide methods for the histochemical detection of non-specific alkaline phosphatase in the light microscope are described and compared with already existing techniques for the light microscopical demonstration of this enzyme. To avoid formation of insoluble lanthanide hydroxide at alkaline pH citrate complexes with the capture ions cerium, lanthanum and didymium were used. A molar ratio of 11 mM citrate/14 mM capture reagent is proposed. For preincubated sections, pretreatment in chloroform-acetone and fixation in glutaraldehyde, for non-preincubated sections fixation in glutaraldehyde yielded the best results. 4-Methylumbelliferyl and 5-Br-4-Cl-3-indoxyl phosphate were found to be the most suitable substrates. For routine purposes 4-nitrophenyl, 1-naphthyl, 2-naphthyl and 2-glycerophosphate were also sufficient; naphthol AS phosphates were inferior but still suitable. After incubation for 5–60 min at 37° C lanthanide phosphate was converted into lead phosphate which was visualized as lead sulfide. At pH 9.2–9.5 enzyme activity was demonstrated at many sites such as intestinal, uterine, placental, renal and epididymal microvillous zones, plasma membranes of arterial, sinus and capillary endothelial cells, vaginal and urethral epithelium, smooth muscle cells, myoepithelial cells as well as excretory duct cells of salivary and lacrimal glands and in secretory granules of laryngeal glands. In comparison with Gomori's calcium, Mayahara's lead, Burstone's and Pearse's azo-coupling, McGadey's tetrazolium salt and Gossrau's azoindoxyl coupling technique the lanthanide methods detected alkaline phosphatase activities at identical or additional sites depending on the respective procedure. However, in contrast to the other methods especially the cerium citrate procedure yielded a more precisely localized and more stable reaction product, can be used with all available alkaline phosphatase substrates including those up till now less suitable or unsuitable for light microscopic alkaline phosphatase histochemistry. 相似文献
42.
In this study we compared the properties of cytochrome-c oxidase (COX) in cultured fibroblasts from two patients with Leigh Syndrome with COX from control fibroblasts. The fibroblasts from patients showed decreased growth reates and elevated lactate production. COX activity of patients fibroblasts was about 25% of control. Kinetic studies with isolated mitochondria showed a higher Km for cytochrome c and a markedly reduced molecular turnover of COX from patients, indicating a different structure of the enzyme. A biphasic change of COX activity was obtained by titration of dodecylmaltoside solubilized mitochondria from control fibroblasts with increasing concentrations of anions. With patient mitochondria we found only the inhibiting phase of COX activity and, in contrast to control mitochondria, irreversible inhibition of COX activity by guanidinium chloride. ELISA titrations with monoclonal antibodies to subunit II, IV, Vab, VIac and VIIab indicated a normal amount of mitochondrial coded subunit II, but a reduced amound of nuclear coded subunits. The data indicate incompletely assembled nuclear coded subunits of COX from patient fibroblasts. 相似文献
43.
The constancy of postmoult/premoult ratios of measures of linear size during ontogeny in insect and other arthropods is widely known as Dyar's rule. We tested this rule in nine species of the waterstrider genera Gerris and Aquarius (Heteroptera: Gerridae), using two size variables: head width and a multivariate measure derived from the pattern of multivariate allometry common to the species considered. Allometric patterns were similar in two independent datasets of laboratory-reared and field-caught specimens. Although our data strictly followed Dyar's rule injust a few instances, all growth ratios varied within a limited range only. Growth ratios for head width differed more between moults than those for multivariate size. The relationship between growth ratios for the two size measures conformed to the predictions based on allometry. We discuss hypotheses of the possible adaptive significance of growth ratios, such as their relation to mobility and systematic differences between hemimetabolous and holometabolous insects, and emphasize the importance of allometry. Since Dyar's rule is consistent with available evidence of physiological mechanisms underlying growth and moulting control of insects and crustaceans, it can be used as a general frame of reference to test alternative growth models. 相似文献
44.
Studies on blastospore production in different liquid media were conducted with three strains of Metarhizium anisopliae var. anisopliae (M. a.) derived from various countries (M. a. 43: Austria, M. a. 57: Brazil, M. a. 97: Philippines). Variation of six fermentation parameters (cornsteep products, carbohydrates, pH values, temperature, Tween 80, and polyethyleneglycol (PEG) 200) disclosed that the three strains of M. anisopliae differed in their growth pattern and physiology. In standard medium and in all tests, M. a. 57 produced the highest number of blastospores invariably amounting to > 108 per ml, while mycelial pellets were never formed. The preferred carbohydrates were glucose and fructose. Blastospore production of M. a. 43 was increased by growth at 30°C, at pH 6.5 or by addition of 5% PEG 200. However, it was impaired by different concentrations of Tween 80 or higher concentrations of PEG 200 (10–15%). M. a. 97 produced most blastospores at 30°C, and the strain preferred basic (pH 8.0) as well as acid (pH 4.5) media. Blastospore production was increased by the addition of 5% PEG 200 or 0.4–1.2% Tween 80. Moreover, PEG 200 suppressed pellet formation effectively. Altogether, our results showed that for optimal blastospore production of Metarhizium anisopliae, suitable strain‐specific parameters have to be evaluated. 相似文献
45.
A microsomal protein is involved in ATP-dependent transport of presecretory proteins into mammalian microsomes. 总被引:8,自引:3,他引:5 下载免费PDF全文
Ribonucleoparticle (i.e. ribosome and SRP)-independent transport of proteins into mammalian microsomes is stimulated by a cytosolic ATPase which involves proteins belonging to the hsp70 family. Here we addressed the question of whether there are additional nucleoside triphosphate requirements involved in this transport mechanism. We employed a purified presecretory protein which upon solubilization in dimethyl sulfoxide and subsequent dilution into an aqueous buffer was processed by and transported into mammalian microsomes in the absence of the cytosolic ATPase. Membrane insertion of this precursor protein was found to depend on the hydrolysis of ATP and to involve a microsomal protein which can be photoaffinity inactivated with azido-ATP. Furthermore, a microsomal protein with a similar sensitivity towards photoaffinity modification with azido-ATP was observed to be involved in ribonucleoparticle-dependent transport. We suggest that a novel microsomal protein which depends on ATP hydrolysis is involved in membrane insertion of both ribonucleoparticle-dependent and -independent precursor proteins. 相似文献
46.
Hanna M. Pappius 《Neurochemical research》1991,16(9):941-949
The studies reviewed here represent a continuing search for mechanisms which play a role in neurological disturbances resulting from brain injury. Focal cortical freezing lesions in rats were shown to cause a widespread decrease in local cerebral glucose utilization (LCGU) in cortical areas of the lesioned hemisphere and this was interpreted as reflecting a depression of cortical activity. Such an interpretation was supported by the finding that in lesioned brain reduction of cerebral metabolism by pentobarbital and isoflurane was limited by the metabolic depression that has already occurred as a result of injury and by the demonstration that the energy status and substrate (glucose) supply in the cortical areas in the injured brain have not been compromised at the time when LCGU was decreased. Both the serotonergic and the noradrenergic neurotransmitter systems were implicated in functional alterations associated with injury. Cortical serotonin (5-HT) metabolism was increased throughout the lesioned hemisphere and complete inhibition of 5-HT synthesis withp-chlorophenylalanine ameliorated the decrease in cortical LCGU, interpreted as reflecting cortical functional depression. Cortical norepinephrine metabolism was bilaterally increased in focally injured brain, while prazosin, a selective 1-noradrenergic receptor blocker, normalized cortical LCGU in the lesioned hemisphere. Low-affinity in vivo binding of [125I]HEAT, another selective 1-receptor ligand, was specifically increased in cortical areas of the lesioned hemisphere at the time of the greatest depression in LCGU, suggesting that 1-adrenoreceptors may be of functional importance in injured brain. The general conclusion from this series of studies on mechanisms underlying functional disturbances in injured brain is that both the serotonergic and the noradrenergic neurotransmitter systems are involved in the widespread cortical depression which develops with time as a consequence of a focal lesion. The data are compatible with the inhibitory effects of NE and 5-HT in the cortex and with the hypothesis that these two transmitter systems affect cortical information processing. 相似文献
47.
Participation of mitochondrial proliferation in morphological differentiation of murine mastocytoma cells 总被引:1,自引:0,他引:1
H Laeng E Schneider R Bolli A Zimmermann T Schaffner R Schindler 《Experimental cell research》1988,179(1):222-232
Proliferation of a cold-sensitive cell-cycle mutant isolated from an undifferentiated murine mastocytoma line is reversibly arrested at the nonpermissive temperature of 33 degrees C, and the arrested cells undergo morphological differentiation as expressed by the formation of metachromatic granules. Following transfer of these mutant cells from the permissive temperature of 39.5 to 33 degrees C, a transient increase in both cytochrome c oxidase and DNA polymerase gamma was observed, the ratio of total mitochondrial volume to cell volume nearly doubled within 6 days, and numbers of mitochondrial cross-sections per cellular cross-section as determined in electron micrographs underwent a threefold increase. Addition of chloramphenicol (100 micrograms/ml) to the mutant cell cultures 6 days prior to transfer from 39.5 to 33 degrees C prevented the increase in the ratio of total mitochondrial to cell volume. Furthermore, chloramphenicol markedly inhibited the increase in granule number per cell that normally is observed after transfer of cultures to 33 degrees C or during treatment with 1 mM butyrate, suggesting that mitochondrial proliferation may be an obligatory step in the process of morphological differentiation of these mastocytoma cells. 相似文献
48.
W M Arnold U Zimmermann W Pauli M Benzing C Niehrs J Ahlers 《Biochimica et biophysica acta》1988,942(1):83-95
The toxicity of 31 phenols was studied by electro-rotation of yeast cells. Control yeast cells show both anti-field and co-field rotation, depending upon the field frequency applied. After treatment with supra-threshold amounts of phenols the anti-field rotation is weakened or abolished and a stronger co-field rotation can be seen. The proportion of cells showing the co-field rotation was found to be a sensitive measure of toxicity. Doses of 2.2 mumol/l of pentachlorophenol, or of 0.3 mumol/l of pentabromophenol were detectable after 3 h incubation at pH 4.0. At a given pH, the toxicity of the chlorophenols correlated extremely well with their octanol:water partition coefficients (Pow). The complete set of phenols showed fair overall correlation with Pow, but less good correlation with their acidity constants (pKa). In particular the toxicity of a given phenol was less than predicted from its pKa if the incubation pH was higher than the pKa. Biochemical assays on 23 of the phenols showed that the rotational sensitivity runs closely parallel to the sensitivities of cell growth rate and of the plasmamembrane ATPase, but less closely to the inhibition of purine incorporation. It appears that the electro-rotation method provides a useful and rapid test for the presence of organic ecotoxins. The test enables us to distinguish differences between single cells, and is comparable in sensitivity to biochemical tests that use vesicles or homogenates derived from a cell population. 相似文献
49.
Divalent cation involvement in the action of Clostridium perfringens type A enterotoxin. Early events in enterotoxin action are divalent cation-independent 总被引:15,自引:0,他引:15
B A McClane A P Wnek K I Hulkower P C Hanna 《The Journal of biological chemistry》1988,263(5):2423-2435
Clostridium perfringens type A enterotoxin (CPE) is a membrane-active cytotoxin. There are a number of recognized early steps in CPE cytotoxicity including binding of CPE to a protein receptor, insertion of CPE into membranes, and CPE-mediated induction of changes in membrane permeability for small molecules such as ions and amino acids. Further support for the existence of these early steps and further characterization of these events are presented in this report. We now report that these early steps in CPE action are largely independent of extracellular divalent cations. It is also shown that 3H-nucleotide release, known to be a later CPE effect, is Ca2+-dependent. A model for CPE cytotoxicity is suggested involving CPE action as a two-step process with Ca2+-independent early steps and Ca2+-dependent late steps. 相似文献
50.
Inactivation of C3a by a monocarboxypeptidase present in culture supernatants of stimulated guinea pig peritoneal macrophages 总被引:1,自引:0,他引:1
G Kreuzpaintner B Damerau B Zimmermann T H Plummer V Brade 《Journal of immunology (Baltimore, Md. : 1950)》1986,136(9):3384-3389
Hog C3a, as well as its derivative C3a-desArg were not found to act cytotoxically on starch gel-induced guinea pig peritoneal macrophages. Likewise, neither peptide significantly modified the secretion of N-acetyl-beta-D-glucosaminidase from these cells. However, C3a rapidly lost its spasmogenic activity during incubation in serum-free macrophage cultures and less rapidly in cellfree supernatants collected from cultured macrophages. The following results indicate that C3a is converted into its spasmogenically inactive derivative C3a-desArg by a macrophage-derived monocarboxypeptidase. The inactivated C3a product does not differ from native C3a in sodium dodecyl sulfate-polyacrylamide gel electrophoresis; it elutes from CM cellulose in the same position as purified C3a-desArg; and it is devoid of the carboxyl-terminal arginyl residue of C3a, but still contains the carboxyl-terminal sequence of C3a-desArg as determined by analysis after treatment with carboxypeptidases B or Y. Furthermore, inactivation of C3a in supernatants of macrophage cultures is completely blocked by the specific carboxypeptidase inhibitors guanidinopropylsuccinic acid and 2-mercaptomethyl-3-guanidinoethylthiopropanoic acid in final concentrations of 10 mM and 2.1 mM, respectively. The monocarboxypeptidase is apparently supplied by biosynthesis of new material but is not stored as a preformed enzyme because cycloheximide markedly inhibits its expression. 相似文献