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211.
The “three‐in‐one” formulation of bismuth quadruple therapy for Helicobacter pylori eradication with or without probiotics supplementation: Efficacy and safety in daily clinical practice 下载免费PDF全文
212.
Marco Tartaglia Sonia Valeri Francesco Velardi Concezio Di Rocco P. A. Battaglia 《Human genetics》1997,99(5):602-606
Pfeiffer syndrome is a skeletal disorder characterized by craniosynostosis associated with foot and hand anomalies. Mutations
in the genes encoding fibroblast growth factor receptors 1 and 2 (FGFR1 and FGFR2) have recently been implicated in the aetiology
of such a syndrome, as well as of other craniosynostotic conditions. We now report a novel missense mutation, a G to C transversion
at position 1049 (exon IIIa) of FGFR2, detected in a patient with severe Pfeiffer clinical features. The mutation results
in the substitution of a cysteine for tryptophan-290 in the third immunoglobulin-like domain and affects both spliceoforms
of FGFR2. Mutations causing replacement of tryptophan-290 have also been reported previously in Crouzon syndrome, a similar
but clinically distinct craniosynostotic disorder. This finding confirms the involvement of mutations of FGFR2 exon IIIa in
Pfeiffer syndrome, and emphasizes both the extensive heterogeneity of the FGFR2 mutations that result in the Pfeiffer phenotype
and the perturbations caused by unpaired cysteine residues in receptor dimerization and transduction of the FGFs signal.
Received: 15 August 1996 / Revised: 19 October 1996 相似文献
213.
M. Bellando S. Sacco F. Albergoni P. Rocco Maria Teresa Marr 《Plant biology (Stuttgart, Germany)》1997,110(5):388-394
A vigorous and transient increase of O2 uptake associated with a simultaneous release of CO2 was elicited in Egeria densa and in Potamogeton crispus leaves by treatment with N-ethylmaleimide (NEM) and by other -SH group reagents (iodoacetate, p-(chloromercuri)benzenesulfonate (p-CMBS), Ag+, Hg2+, Cu2+). The NEM-induced respiratory burst was apparent even in the absence of photosynthesis (darkness, or presence of DCMU) as well as in the presence of the respiration inhibitors cyanide and propyl gallate or SHAM, separate or in combination. In contrast, a complete suppression of the respiratory burst was induced by diphenylene iodonium and by quinacrine, inhibitors of the plasma membrane NADPH oxidase activated in the pathogen-elicited oxidative burst in granulocytes and in plants. The respiratory burst induced by NEM and by the uncoupler CCCP were additive. The intensity of the respiratory burst was markedly decreased by increasing the pH of the medium from 5 to 8, and partially decreased by the presence of K+ in the medium. Azide inhibited the burst (as well as basal respiration) at pH 6.5 but not at pH 5. The stimulation of QO2 by SH reagents was associated with an early, pronounced membrane depolarization together with a rapid increase of the release into the medium of K+ and other electrolytes, and with a rapid decrease of the intracellular ATP, ADP and G6 P contents. The possible relationships between this SH reagent-induced respiratory burst and the associated effects on Em and electrolyte leakage are discussed. 相似文献
214.
Regina Hühn Heike Stoermer Beate Klingele Elke Bausch Alberto Fois Mariangela Farnetani Maja Di Rocco Joelle Boué Jean M. Kirk Rosalind Coleman G. Scherer 《Human genetics》1998,102(3):305-313
Tyrosinemia typeII (Richner-Hanhart syndrome, RHS) is a disorder of autosomal recessive inheritance characterized by keratitis,
palmoplantar hyperkeratosis, mental retardation, and elevated blood tyrosine levels. The disease results from deficiency in
hepatic tyrosine aminotransferase (TAT). We have previously described one deletion and six different point mutations in four
RHS patients. We have now analyzed the TAT genes in a further seven unrelated RHS families from Italy, France, the United Kingdom, and the United States. We have established
PCR conditions for the amplification of all twelve TAT exons and have screened the products for mutations by direct sequence analysis or by first performing single-strand conformation
polymorphism analysis. We have thus identified the presumably pathological mutations in eight RHS alleles, including two nonsense
mutations (R57X, E411X) and four amino acid substitutions (R119W, L201R, R433Q, R433W). Only the R57X mutation, which was
found in one Scottish and two Italian families, has been previously reported in another Italian family. Haplotype analysis
indicates that this mutation, which involves a CpG dinucleotide hot spot, has a common origin in the three Italian families
but arose independently in the Scottish family. Two polymorphisms have also been detected, viz., a protein polymorphism, P15S,
and a silent substitution S103S (TCG→TCA). Expression of R433Q and R433W demonstrate reduced activity of the mutant proteins.
In all, twelve different TAT gene mutations have now been identified in tyrosinemia typeII.
Received: 8 October 1997 / Accepted: 29 October 1997 相似文献
215.
216.
Rosa Gaglione Giovanni Smaldone Rocco Di Girolamo Renata Piccoli Emilia Pedone Angela Arciello 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(3):377-384
Background
Specific apolipoprotein A-I variants are associated to severe hereditary amyloidoses. The organ distribution of AApoAI amyloidosis seems to depend on the position of the mutation, since mutations in residues from 1 to 75 are mainly associated to hepatic and renal amyloidosis, while mutations in residues from 173 to 178 are mostly responsible for cardiac, laryngeal, and cutaneous amyloidosis. Molecular bases of this tissue specificity are still poorly understood, but it is increasingly emerging that protein destabilization induced by amyloidogenic mutations is neither necessary nor sufficient for amyloidosis development.Methods
By using a multidisciplinary approach, including circular dichroism, dynamic light scattering, spectrofluorometric and atomic force microscopy analyses, the effect of target cells on the conformation and fibrillogenic pathway of the two AApoAI amyloidogenic variants AApoAIL75P and AApoAIL174S has been monitored.Results
Our data show that specific cell milieus selectively affect conformation, aggregation propensity and fibrillogenesis of the two AApoAI amyloidogenic variants.Conclusions
An intriguing picture emerged indicating that defined cell contexts selectively induce fibrillogenesis of specific AApoAI variants.General significance
An innovative methodological approach, based on the use of whole intact cells to monitor the effects of cell context on AApoAI variants fibrillogenic pathway, has been set up. 相似文献217.
Genome size and A-T rich DNA in selachians 总被引:2,自引:0,他引:2
The nuclear DNA content of 23 selachian species (10 Batoidea, 11 Galeomorphii, and 2 Squalomorphii) was histophotometrically studied. Their genome sizes range from 7.5 pg/N in Raja fillae (Batoidea) to 34.1 pg/N in Oxynotus centrina (Squalomorphii).Results show slight differences in the pattern of quantitative variations between the superorders Batoidea and Galeomorphii; Squalomorphii preserve their peculiar wide interspecific variability at the intrafamilial level, with values sited between 13.1 and 34.1 pg/N.In 21 species also the DNA base composition was determined by means of DAPI. The study shows that in the species examined the DAPI positive fraction varies from a minimum of 27.7% in Oxynotus centrina, which possesses the largest genome size among all the Selachians studied, to a maximum of 72.5% in Carcharhinus limbatus. As a whole the data show an inverse correlation between the DNA content and the DAPI positive fraction, a condition common to all cold-blooded vertebrates.The low percentage of DAPI positive DNA found in Oxynotus centrina could be attributable to a lower stainability by the fluorochrome caused by a higher chromatin condensation in the erythrocytes.The validity of the DAPI method was verified by comparison with the biochemical assay according to the thermal denaturation method in 6 selachian species. 相似文献
218.
F Mantero S Rocco F Pertile G Carpené F Fallo A Menegus 《Journal of steroid biochemistry》1987,27(4-6):935-940
Atrial natriuretic peptide, a hormone secreted by the heart, is involved in salt and fluid homeostasis and also exerts an inhibitory effect on aldosterone production in vitro. In order to elucidate if this effect is also present in man, 6 normal volunteers, 5 low renin hypertensive patients (LRH) and 7 patients with primary aldosteronism (PA) have received 100 micrograms of alpha-h-Anp as bolus i.v. (The decrease in blood pressure was mild and transient in all groups, whereas a marked diuretic effect was observed in all hypertensives even in PA where high levels of endogenous ANP have been found. In normals we observed a significant decrease of plasma aldosterone values while in PA and LRH this effect was not evident. This phenomenon associated with a greater natriuretic effect in LRH and PA, as compared with normals, demonstrates the lack of the correlation between ANP-induced diuresis and aldosterone inhibiting properties. 相似文献
219.
Rocco L. Mancinelli Sonja Cronin Lawrence I. Hochstein 《Archives of microbiology》1986,145(2):202-208
Paracoccus halodenitrificans, grown anaerobically in the presence of nitrite, contained membrane and cytoplasmic nitrite reductases. When assayed in the presence of phenazine methosulfate and ascorbate, the membranebound enzyme produced nitrous oxide whereas the cytoplasmic enzyme produced nitric oxide. When both enzymes were assayed in the presence of methyl viologen and dithionite, the cytoplasmic enzyme produced ammonia. Following solubilization, the membrane-bound enzyme behaved like the cytoplasmic enzyme, producing nitric oxide in the presence of phenazine methosulfate and ascorbate, and ammonia when assayed in the presence of methyl viologen and dithionite. The cytoplasmic and membranebound enzymes were purified to essentially the same specific activity. Only a single nitrite-reductase activity was detected on electrophoretic gels and the electrophoretic behavior of both enzymes suggested they were identical. The spectral properties of both enzymes suggested they were cd-type cytochromes. These data suggest that the products of nitrite reduction by the cd-cytochrome nitrite reductase are determined by the location of the enzyme and the redox potential of the electron donor.Abbreviations PMS
phenazine methosulfate
- MV
methyl viologen
- HEPES
N-2-hydroxyethylpiperazine-N-2-ethane-sulfonic acid
- CHAPSO
[3-(3-cholamidopropyldimethylammonia)-1-(2-hydroxy-1-propanesulfonate)]
National Research Council Research Fellow 相似文献
220.
The ribosomal RNA genes ofTriturus vulgaris meridionalis are clustered at variable and often multiple chromosomal loci. The rDNA repeats exhibit only a limited and discrete length heterogeneity which is accounted for by the non-transcribed spacer (NTS). Interestingly, sequences homologous to the NTS are clustered outside the ribosomal loci. Clones containing such non ribosomal sequences have been isolated from a genomic library ofT. v. meridionalis and analyzed by restriction mapping. These sequences appear to consist mostly of repetitive Bam HI fragments ranging from 500 bp to 1000 bp. The Bam HI fragments are internally repetitious and highly homologous to each other. 相似文献