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11.
Charlie Strange Felix JF Herth Kevin L Kovitz Geoffrey McLennan Armin Ernst Jonathan Goldin Marc Noppen Gerard J Criner Frank C Sciurba 《BMC pulmonary medicine》2007,7(1):1-12
Background
Lung volume reduction surgery is effective at improving lung function, quality of life, and mortality in carefully selected individuals with advanced emphysema. Recently, less invasive bronchoscopic approaches have been designed to utilize these principles while avoiding the associated perioperative risks. The Endobronchial Valve for Emphysema PalliatioN Trial (VENT) posits that occlusion of a single pulmonary lobe through bronchoscopically placed Zephyr® endobronchial valves will effect significant improvements in lung function and exercise tolerance with an acceptable risk profile in advanced emphysema.Methods
The trial design posted on Clinical trials.gov, on August 10, 2005 proposed an enrollment of 270 subjects. Inclusion criteria included: diagnosis of emphysema with forced expiratory volume in one second (FEV1) < 45% of predicted, hyperinflation (total lung capacity measured by body plethysmography > 100%; residual volume > 150% predicted), and heterogeneous emphysema defined using a quantitative chest computed tomography algorithm. Following standardized pulmonary rehabilitation, patients were randomized 2:1 to receive unilateral lobar placement of endobronchial valves plus optimal medical management or optimal medical management alone. The co-primary endpoint was the mean percent change in FEV1 and six minute walk distance at 180 days. Secondary end-points included mean percent change in St. George's Respiratory Questionnaire score and the mean absolute changes in the maximal work load measured by cycle ergometry, dyspnea (mMRC) score, and total oxygen use per day. Per patient response rates in clinically significant improvement/maintenance of FEV1 and six minute walk distance and technical success rates of valve placement were recorded. Apriori response predictors based on quantitative CT and lung physiology were defined.Conclusion
If endobronchial valves improve FEV1 and health status with an acceptable safety profile in advanced emphysema, they would offer a novel intervention for this progressive and debilitating disease.Trial Registration
ClinicalTrials.gov: NCT00129584 相似文献12.
Liliane?VenturaEmail author Gabriel?Torres?de Jesus Gunter?Camilo Dablas?de Oliveira Sidney?JF?Sousa 《Biomedical engineering online》2005,4(1):70
Background
The authors have developed a small portable device for the objective measurement of the transparency of corneas stored in preservative medium, for use by eye banks in evaluation prior to transplantation. 相似文献13.
Store-operated Ca2+ entry modulates sarcoplasmic reticulum Ca2+ loading in neonatal rabbit cardiac ventricular myocytes 总被引:1,自引:0,他引:1
Huang J van Breemen C Kuo KH Hove-Madsen L Tibbits GF 《American journal of physiology. Cell physiology》2006,290(6):C1572-C1582
Store-operated Ca2+ entry (SOCE), which is Ca2+ entry triggered by the depletion of intracellular Ca2+ stores, has been observed in many cell types, but only recently has it been suggested to occur in cardiomyocytes. In the present study, we have demonstrated SOCE-dependent sarcoplasmic reticulum (SR) Ca2+ loading (loadSR) that was not altered by inhibition of L-type Ca2+ channels, reverse mode Na+/Ca2+ exchange (NCX), or nonselective cation channels. In contrast, lowering the extracellular [Ca2+] to 0 mM or adding either 0.5 mM Zn2+ or the putative store-operated channel (SOC) inhibitor SKF-96365 (100 µM) inhibited loadSR at rest. Interestingly, inhibition of forward mode NCX with 30 µM KB-R7943 stimulated SOCE significantly and resulted in enhanced loadSR. In addition, manipulation of the extracellular and intracellular Na+ concentrations further demonstrated the modulatory role of NCX in SOCE-mediated SR Ca2+ loading. Although there is little knowledge of SOCE in cardiomyocytes, the present results suggest that this mechanism, together with NCX, may play an important role in SR Ca2+ homeostasis. The data reported herein also imply the presence of microdomains unique to the neonatal cardiomyocyte. These findings may be of particular importance during open heart surgery in neonates, in which uncontrolled SOCE could lead to SR Ca2+ overload and arrhythmogenesis. cardiac ontogeny; cardiac excitation-contraction coupling; calcium homeostasis 相似文献
14.
RP Tucker K Drabikowski JF Hess J Ferralli R Chiquet-Ehrismann JC Adams 《BMC evolutionary biology》2006,6(1):60-17
Background
Tenascins are a family of glycoproteins found primarily in the extracellular matrix of embryos where they help to regulate cell proliferation, adhesion and migration. In order to learn more about their origins and relationships to each other, as well as to clarify the nomenclature used to describe them, the tenascin genes of the urochordate Ciona intestinalis, the pufferfish Tetraodon nigroviridis and Takifugu rubripes and the frog Xenopus tropicalis were identified and their gene organization and predicted protein products compared with the previously characterized tenascins of amniotes. 相似文献15.
Background
Trichomonosis caused by Trichomonas vaginalis is the number one, non-viral sexually transmitted disease (STD) that affects more than 250 million people worldwide. Immunoglobulin A (IgA) has been implicated in resistance to mucosal infections by pathogens. No reports are available of IgA-reactive proteins and the role, if any, of this class of antibody in the control of this STD. The availability of an IgA monoclonal antibody (mAb) immunoreactive to trichomonads by whole cell (WC)-ELISA prompted us to characterize the IgA-reactive protein of T. vaginalis. 相似文献16.
Huang J Hove-Madsen L Tibbits GF 《American journal of physiology. Cell physiology》2008,294(2):C516-C525
It is commonly accepted that L-type Ca(2+) channel-mediated Ca(2+)-induced Ca(2+) release (CICR) is the dominant mode of excitation-contraction (E-C) coupling in the adult mammalian heart and that there is no appreciable CICR in neonates. However, we have observed that cell contraction in the neonatal heart was significantly decreased after sarcoplasmic reticulum (SR) Ca(2+) depletion with caffeine. Therefore, the present study investigated the developmental changes of CICR in rabbit ventricular myocytes at 3, 10, 20, and 56 days of age. We found that the inhibitory effect of the L-type Ca(2+) current (I(Ca)) inhibitor nifedipine (Nif; 15 microM) caused an increasingly larger reduction of Ca(2+) transients on depolarization in older age groups [from approximately 15% in 3-day-old (3d) myocytes to approximately 90% in 56-day-old (56d) myocytes]. The remaining Ca(2+) transient in the presence of Nif in younger age groups was eliminated by the inhibition of Na(+)/Ca(2+) exchanger (NCX) with the subsequent addition of 10 microM KB-R7943 (KB-R). Furthermore, Ca(2+) transients were significantly reduced in magnitude after the depletion of SR Ca(2+) with caffeine in all age groups, although the effect was significantly greater in the older age groups (from approximately 40% in 3d myocytes up to approximately 70% in 56d myocytes). This SR Ca(2+)-sensitive Ca(2+) transient in the earliest developmental stage was insensitive to Nif but was sensitive to the subsequent addition of KB-R, indicating the presence of NCX-mediated CICR that decreased significantly with age (from approximately 37% in 3d myocytes to approximately 0.5% in 56d myocytes). In contrast, the I(Ca)-mediated CICR increased significantly with age (from approximately 10% in 3d myocytes to approximately 70% in 56d myocytes). The CICR gain as estimated by the integral of the CICR Ca(2+) transient divided by the integral of its Ca(2+) transient trigger was smaller when mediated by NCX ( approximately 1.0 for 3d myocytes) than when mediated by I(Ca) ( approximately 3.0 for 56d myocytes). We conclude that the lower-efficiency NCX-mediated CICR is a predominant mode of CICR in the earliest developmental stages that gradually decreases as the more efficient L-type Ca(2+) channel-mediated CICR increases in prominence with ontogeny. 相似文献
17.
18.
Extreme differences in rates of molecular evolution of foraminifera revealed by comparison of ribosomal DNA sequences and the fossil record 总被引:8,自引:3,他引:5
Pawlowski J; Bolivar I; Fahrni JF; de Vargas C; Gouy M; Zaninetti L 《Molecular biology and evolution》1997,14(5):498-505
Foraminifera have one of the best known fossil records among the
unicellular eukaryotes. However, the origin and phylogenetic relationships
of the extant foraminiferal lineages are poorly understood. To test the
current paleontological hypotheses on evolution of foraminifera, we
sequenced about 1,000 base pairs from the 3' end of the small subunit rRNA
gene (SSU rDNA) in 22 species representing all major taxonomic groups.
Phylogenies were derived using neighbor- joining, maximum-parsimony, and
maximum-likelihood methods. All analyses confirm the monophyletic origin of
foraminifera. Evolutionary relationships within foraminifera inferred from
rDNA sequences, however, depend on the method of tree building and on the
choice of analyzed sites. In particular, the position of planktonic
foraminifera shows important variations. We have shown that these changes
result from the extremely high rate of rDNA evolution in this group. By
comparing the number of substitutions with the divergence times inferred
from the fossil record, we have estimated that the rate of rDNA evolution
in planktonic foraminifera is 50 to 100 times faster than in some benthic
foraminifera. The use of the maximum-likelihood method and limitation of
analyzed sites to the most conserved parts of the SSU rRNA molecule render
molecular and paleontological data generally congruent.
相似文献
19.
JF Yuan SJ Zhang O Jafer RA Furlong OE Chausiaux CA Sargent GH Zhang NA Affara 《BMC microbiology》2009,9(1):246
Background
Pseudorabies virus (PRV) is an alphaherpesviruses whose native host is pig. PRV infection mainly causes signs of central nervous system disorder in young pigs, and respiratory system diseases in the adult. 相似文献20.