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1.
Abstract In Arabidopsis thaliana, cell fate in developing ovules is determined by the action of the homeodomain factor BELL1 (BEL1) and of the MADS-box factors SEEDSTICK (STK), SHATTERPROOF1 (SHP1) and SHP2. The analysis of the bel1 and the stk shp1 shp2 mutants revealed that the functional megaspore is formed, however, it does not proceed into megagametogenesis. In the bel1 stk shp1 shp2, quadruple mutant megasporogenesis does not take place. In this article we describe a detailed morphological analysis of the quadruple mutant, and we discuss the possibility that BELL1, STK, SHP1 and SHP2 not only control integument identity determination and development, but that they might also play a role during megasporogenesis. 相似文献
2.
Paolo d’Errico Marina Boido Antonio Piras Valeria Valsecchi Elena De Amicis Denise Locatelli Silvia Capra Francesco Vagni Alessandro Vercelli Giorgio Battaglia 《PloS one》2013,8(12)
Loss of the survival motor neuron gene (SMN1) is responsible for spinal muscular atrophy (SMA), the most common inherited cause of infant mortality. Even though the SMA phenotype is traditionally considered as related to spinal motor neuron loss, it remains debated whether the specific targeting of motor neurons could represent the best therapeutic option for the disease. We here investigated, using stereological quantification methods, the spinal cord and cerebral motor cortex of ∆7 SMA mice during development, to verify extent and selectivity of motor neuron loss. We found progressive post-natal loss of spinal motor neurons, already at pre-symptomatic stages, and a higher vulnerability of motor neurons innervating proximal and axial muscles. Larger motor neurons decreased in the course of disease, either for selective loss or specific developmental impairment. We also found a selective reduction of layer V pyramidal neurons associated with layer V gliosis in the cerebral motor cortex. Our data indicate that in the ∆7 SMA model SMN loss is critical for the spinal cord, particularly for specific motor neuron pools. Neuronal loss, however, is not selective for lower motor neurons. These data further suggest that SMA pathogenesis is likely more complex than previously anticipated. The better knowledge of SMA models might be instrumental in shaping better therapeutic options for affected patients. 相似文献
3.
S K Paulson H F DeLuca F Battaglia 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1987,185(3):267-271
The plasma concentrations of calcium; inorganic phosphorus; 25-hydroxyvitamin D; 24,25-dihydroxyvitamin D; and 1,25-dihydroxyvitamin D were determined in sheep maternal and fetal arterial circulations. In addition, plasma concentrations of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D were determined simultaneously across the uterine and umbilical circulations. Fetal arterial levels of calcium (r = 0.560); inorganic phosphorus (r = -0.095); and 1,25-dihydroxyvitamin D (r = 0.040) were significantly higher than and did not correlate with maternal arterial levels. Maternal levels of 25-hydroxyvitamin D were significantly higher than and correlated (r = 0.693) with fetal 25-hydroxyvitamin D levels. No significant difference existed between maternal and fetal arterial levels of 24,25-dihydroxyvitamin D. No significant difference was detected in the concentrations of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D across the uterine or umbilical circulations. 相似文献
4.
Piero A. Battaglia Franca Gigliani Liana Marcucci Raffaella Elli 《Molecular & general genetics : MGG》1987,209(1):41-48
Summary By using an artificial hybrid between phage and the pR plasmid, we have shown that the rep region of the pR plasmid encodes a function which regulates the expression of the muc genes (plasmid genes that are under the negative control of lexA and responsible for an increased rate of spontaneous mutagenesis and resistance to UV and chemicals). Expression of the muc genes was monitored by a fusion between the muc promoter and the lacZ structural gene. When E. coli cells containing such a fusion are infected by the hybrid pR phasmid, -galactosidase activity is enhanced, indicating that pR encodes an antagonist of lexA. By deletion mapping we have located the gene encoding the antagonist of lexA (bat) in the rep region of the plasmid. The bat gene product can also antagonize the cI repressor as shown by the observation that pR phasmids are virulent on a homoimmune lysogen. We have exploited this latter property to carry out genetic and functional analysis of the bat region. This region is organized as a classical operon where the expression of the bat structural gene is negatively regulated by a repressor gene that encodes a proteic product. 相似文献
5.
G. Chatellier C. Battaglia J. Y. Pagny P. F. Plouin J. Ménard 《BMJ (Clinical research ed.)》1992,305(6861):1062
OBJECTIVE--To determine if one ambulatory blood pressure recording over 12 hours could detect those patients with mild hypertension who needed treatment according to the World Health Organisation-International Society of Hypertension (ISH) guidelines based on the causal measurement of diastolic blood pressure at successive visits to a clinic. DESIGN--Comparison of decision to treat based on one ambulatory measurement over 12 hours and standard blood pressure measurements over six months in the same patients. SETTING--Outpatient hypertension clinic. SUBJECTS--130 men and women with diastolic blood pressure of 90-104 mm Hg at second visit to clinic. MAIN OUTCOME MEASURES--Blood pressure measurements over six months. Measurement from ambulatory monitoring. Decision to treat. RESULTS--Of the 130 patients included, 108 were followed up over the six months. Treatment was started according to WHO-ISH criteria in 44 (13 at the third visit, 13 at the fourth, 18 at the fifth). According to the selected criteria for ambulatory blood pressure monitoring 41 patients would have been treated. Both methods agreed that the same 27 patients required treatment and the same 50 did not, but they did not agree in 31 patients. When calculated at the optimal diastolic blood pressure threshold determined by a receiver operating characteristic curve, the sensitivity, specificity, and positive predictive value of ambulatory blood pressure monitoring were 71% (95% confidence interval 57% to 84%), 82% (72% to 92%), and 66% (51% to 81%), respectively. CONCLUSION--If the WHO-ISH criteria are accepted as the standard for deciding to treat patients with mild hypertension the predictive value of one ambulatory blood pressure recording over 12 hours is too low to detect with confidence those patients who need treatment when managed according to these criteria. 相似文献
6.
P R Meier D K Manchester F C Battaglia G Meschia 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1983,172(1):107-110
In contrast to the inverse relation of heart rate to body mass in adult mammals, the heart rate of immature fetuses is unrelated to body mass and approximately constant among different species. With maturation, fetal heart rate decreases in a large mammal but tends to increase in a small mammal. These maturational changes reduce the difference between the heart rate of a term fetus and the heart rate which is "appropriate for body mass" as calculated by means of the allometric equation for adults. The comparative physiology of fetal heart rate supports the hypothesis that immature fetuses of small and large mammals have similar oxygen consumption rates per unit body mass. 相似文献
7.
8.
Derek G. Smyth Frederick C. Battaglia Giacomo Meschia 《The Journal of general physiology》1961,44(5):889-898
A simple method is described for the measurement of pH changes in hemoglobin solutions on oxygenation and reduction. Data are presented establishing the absence of a Bohr effect in p-chloromercuribenzoate [PCMB] treated hemoglobin. The influence of a number of sulfhydryl inhibitors on the Bohr effect of a hemoglobin solution is reported and an interpretation based on steric factors in the protein is proposed. 相似文献
9.
10.
Alexander Mironov Antonino Colanzi Maria Giuseppina Silletta Giusy Fiucci Silvio Flati Aurora Fusella Roman Polishchuk Alexander Mironov Jr. Giuseppe Di Tullio Roberto Weigert Vivek Malhotra Daniela Corda Maria Antonietta De Matteis Alberto Luini 《The Journal of cell biology》1997,139(5):1109-1118
We have investigated the role of the ADP- ribosylation induced by brefeldin A (BFA) in the mechanisms controlling the architecture of the Golgi complex. BFA causes the rapid disassembly of this organelle into a network of tubules, prevents the association of coatomer and other proteins to Golgi membranes, and stimulates the ADP-ribosylation of two cytosolic proteins of 38 and 50 kD (GAPDH and BARS-50; De Matteis, M.A., M. DiGirolamo, A. Colanzi, M. Pallas, G. Di Tullio, L.J. McDonald, J. Moss, G. Santini, S. Bannykh, D. Corda, and A. Luini. 1994. Proc. Natl. Acad. Sci. USA. 91:1114–1118; Di Girolamo, M., M.G. Silletta, M.A. De Matteis, A. Braca, A. Colanzi, D. Pawlak, M.M. Rasenick, A. Luini, and D. Corda. 1995. Proc. Natl. Acad. Sci. USA. 92:7065–7069). To study the role of ADP-ribosylation, this reaction was inhibited by depletion of NAD+ (the ADP-ribose donor) or by using selective pharmacological blockers in permeabilized cells. In NAD+-depleted cells and in the presence of dialized cytosol, BFA detached coat proteins from Golgi membranes with normal potency but failed to alter the organelle's structure. Readdition of NAD+ triggered Golgi disassembly by BFA. This effect of NAD+ was mimicked by the use of pre–ADP- ribosylated cytosol. The further addition of extracts enriched in native BARS-50 abolished the ability of ADP-ribosylated cytosol to support the effect of BFA. Pharmacological blockers of the BFA-dependent ADP-ribosylation (Weigert, R., A. Colanzi, A. Mironov, R. Buccione, C. Cericola, M.G. Sciulli, G. Santini, S. Flati, A. Fusella, J. Donaldson, M. DiGirolamo, D. Corda, M.A. De Matteis, and A. Luini. 1997. J. Biol. Chem. 272:14200–14207) prevented Golgi disassembly by BFA in permeabilized cells. These inhibitors became inactive in the presence of pre–ADP-ribosylated cytosol, and their activity was rescued by supplementing the cytosol with a native BARS-50–enriched fraction. These results indicate that ADP-ribosylation plays a role in the Golgi disassembling activity of BFA, and suggest that the ADP-ribosylated substrates are components of the machinery controlling the structure of the Golgi apparatus. 相似文献