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171.
Jaenisch RB Hentschke VS Quagliotto E Cavinato PR Schmeing LA Xavier LL Dal Lago P 《Journal of applied physiology (Bethesda, Md. : 1985)》2011,111(6):1664-1670
Respiratory muscle training (RMT) improves functional capacity in chronic heart-failure (HF) patients, but the basis for this improvement remains unclear. We evaluate the effects of RMT on the hemodynamic and autonomic function, arterial baroreflex sensitivity (BRS), and respiratory mechanics in rats with HF. Rats were assigned to one of four groups: sedentary sham (n = 8), trained sham (n = 8), sedentary HF (n = 8), or trained HF (n = 8). Trained animals underwent a RMT protocol (30 min/day, 5 day/wk, 6 wk of breathing through a resistor), whereas sedentary animals did not. In HF rats, RMT had significant effects on several parameters. It reduced left ventricular (LV) end-diastolic pressure (P < 0.01), increased LV systolic pressure (P < 0.01), and reduced right ventricular hypertrophy (P < 0.01) and pulmonary (P < 0.001) and hepatic (P < 0.001) congestion. It also decreased resting heart rate (HR; P < 0.05), indicating a decrease in the sympathetic and an increase in the vagal modulation of HR. There was also an increase in baroreflex gain (P < 0.05). The respiratory system resistance was reduced (P < 0.001), which was associated with the reduction in tissue resistance after RMT (P < 0.01). The respiratory system and tissue elastance (Est) were also reduced by RMT (P < 0.01 and P < 0.05, respectively). Additionally, the quasistatic Est was reduced after RMT (P < 0.01). These findings show that a 6-wk RMT protocol in HF rats promotes an improvement in hemodynamic function, sympathetic and vagal heart modulation, arterial BRS, and respiratory mechanics, all of which are benefits associated with improvements in cardiopulmonary interaction. 相似文献
172.
Sorragi Cde L Shishido SM Lemos ME Marcondes S Antunes E Krieger MH 《Cell biochemistry and function》2011,29(3):207-214
Drug‐eluting stents (DES) were developed to combat the problem of in‐stent restenosis, and evaluating the biological activity from DES systems is critical for its safety and efficacy. To test the cytotoxicity of nitric oxide (NO) donor‐containing polymers for their potential use in DES applications, S‐nitrosoglutathione (GSNO) or in combination with poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP) in an aqueous polymeric solution (PVA/PVP/GSNO) was investigated using Balb/c 3T3 and Rabbit arterial smooth muscle (RASM) cells. The sensitivity of 3T3 cells to the cytotoxicity effects induced by GSNO was higher than that of RASM cells, while RASM cells were more susceptible to alterations in membrane permeability. Cell growth assays showed that GSNO and PVA/PVP/GSNO induced antiproliferative effects in RASM cells. Moreover, the presence of polymers can reduce the cytotoxicity and enhance the antiproliferative effects of GSNO. Dose‐dependent inhibition of platelet aggregation was similar for both PVA/PVP/GSNO (EC50 of 3.4 ± 2.3 µM) and GSNO (EC50 of 2.8 ± 1.1 µM) solutions. Platelet adhesion assays showed that the inhibition caused by GSNO (EC50 of 5.0 mM) was dependent on the presence of plasma. These results demonstrate that the methodology adopted here is suitable to establish safety margins and evaluate the antithrombotic potential and antiproliferative effects of NO‐eluting biomaterials and polymeric solutions for the new cardiovascular devices, and also to emphasize the importance of using more specific cell lines in these evaluations. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
173.
Barros AR Adorno MA Sakamoto IK Maintinguer SI Varesche MB Silva EL 《Bioresource technology》2011,102(4):3840-3847
This study evaluated two different support materials (ground tire and polyethylene terephthalate [PET]) for biohydrogen production in an anaerobic fluidized bed reactor (AFBR) treating synthetic wastewater containing glucose (4000 mg L−1). The AFBR, which contained either ground tire (R1) or PET (R2) as support materials, were inoculated with thermally pretreated anaerobic sludge and operated at a temperature of 30 °C. The AFBR were operated with a range of hydraulic retention times (HRT) between 1 and 8 h. The reactor R1 operating with a HRT of 2 h showed better performance than reactor R2, reaching a maximum hydrogen yield of 2.25 mol H2 mol−1 glucose with 1.3 mg of biomass (as the total volatile solids) attached to each gram of ground tire. Subsequent 16S rRNA gene sequencing and phylogenetic analysis of particle samples revealed that reactor R1 favored the presence of hydrogen-producing bacteria such as Clostridium, Bacillus, and Enterobacter. 相似文献
174.
Claudino MA Delbin MA Franco-Penteado CF Priviero FB De Nucci G Antunes E Zanesco A 《Life sciences》2011,88(5-6):272-277
AimsThe effect of exercise training (ET) on vascular responsiveness in diabetes mellitus has been largely well studied. However, limited studies have investigated the effects of ET on functional responses of the corpus cavernosum (CC) in diabetic animals. Therefore, the aim of this study was to investigate whether prior ET prevents the impairment of erectile function in streptozotocin-induced diabetic rats.Main methodsRats were exercised for four weeks prior to the induction of diabetes, and then again for another 4 weeks thereafter. Concentration–response curves to acetylcholine, sodium nitroprusside, Y-27632, BAY 412272 and phenylephrine (PE) were obtained in CC. The excitatory and inhibitory effects of electrical-field stimulation were also evaluated.Key findingsPlasma SOD levels were markedly decreased in the sedentary diabetic group (D-SD) as compared to control sedentary animals (C-SD), approximately 53% (P < 0.05) and this reduction was restored in trained diabetic animals. Physical training restored the impairment of endothelium-dependent and -independent relaxation responses seen in the D-SD group. The potency values for Y-27632 in the CC were significantly reduced in the D-SD group, which was reversed by physical training. The impairment of electrical-field stimulation (EFS)-induced relaxation seen in the D-SD group was restored by physical training. On the other hand, both EFS-induced contractions and concentration–response curves to PE in cavernosal strips were not modified by either diabetes or physical training.SignificancePractice of regular physical exercise may be an important approach in preventing erectile dysfunction associated with diabetes mellitus by re-establishment of the balance between NO production and its inactivation. 相似文献
175.
Jorge RS Ferreira F Ferreira Neto JS Vasconcellos Sde A Lima Ede S Morais ZM Souza GO 《Memórias do Instituto Oswaldo Cruz》2011,106(4):441-444
Leptospirosis is a zoonotic disease affecting most mammals and is distributed throughout the world. Several species of domestic and wild animals may act as reservoirs for this disease. The purpose of this study was to assess the exposure of free-ranging wild carnivores, horses and domestic dogs on a private reserve located in the northern Pantanal (Brazil) and the surrounding areas to Leptospira spp from 2002-2006, 75 free-ranging wild carnivores were captured in the Pantanal and serum samples were collected. In addition, samples from 103 domestic dogs and 23 horses in the region were collected. Serum samples were tested for the presence of Leptospira antibodies using the microscopic agglutination test. Thirty-two wild carnivores (42.7%) were considered positive with titres ≥ 100, and 18 domestic dogs (17.5%) and 20 horses (74.1%) were also found to be positive. Our study showed that horses, dogs and several species of free-ranging wild carnivores have been exposed to Leptospira spp in the Pantanal, suggesting that the peculiar characteristics of this biome, such as high temperatures and an extended period of flooding, may favour bacterial persistence and transmission. In this region, wild carnivores and horses seem to be important hosts for the epidemiology of Leptospira species. 相似文献
176.
Coen SJ Gregory LJ Yágüez L Amaro E Brammer M Williams SC Aziz Q 《American journal of physiology. Gastrointestinal and liver physiology》2007,293(1):G188-G197
Functional MRI is a popular tool for investigating central processing of visceral pain in healthy and clinical populations. Despite this, the reproducibility of the neural correlates of visceral sensation by use of functional MRI remains unclear. The aim of the present study was to address this issue. Seven healthy right-handed volunteers participated in the study. Blood oxygen level-dependent contrast images were acquired at 1.5 T while subjects received nonpainful and painful phasic balloon distensions ("on-off" block design, 10 stimuli per "on" period, 0.3 Hz) to the distal esophagus. This procedure was repeated on two further occasions to investigate reproducibility. Painful stimulation resulted in highly reproducible activation over three scanning sessions in the anterior insula, primary somatosensory cortex, and anterior cingulate cortex. A significant decrease in strength of activation occurred from session 1 to session 3 in the anterior cingulate cortex, primary somatosensory cortex, and supplementary motor cortex, which may be explained by an analogous decrease in pain ratings. Nonpainful stimulation activated similar brain regions to painful stimulation, but with greater variability in signal strength and regions of activation between scans. Painful stimulation of the esophagus produces robust activation in many brain regions. A decrease in subjective perception of pain and brain activity from the first to the final scan suggests that serial brain imaging studies may be affected by habituation. These findings indicate that for brain imaging studies that require serial scanning, development of experimental paradigms that control for the effect of habituation is necessary. 相似文献
177.
Bianca Ferrarini Zanetti Daniela Paes de Almeida Ferreira Braga Amanda Souza Setti Assumpto Iaconelli Jr. Edson Borges Jr. 《Reproductive biology》2019,19(1):55-60
The aim of this study was to investigate which factors contribute to the incidence of biochemical pregnancy (BP) in intracytoplasmic sperm injection (ICSI) cycles. This cohort study included cycles performed from June 2010 to September 2016 in a private, university-affiliated IVF centre. Cycles were split into four groups, depending on the pregnancy outcomes: Clinical Pregnancy (CP, n?=?903), Biochemical Pregnancy (BP, n?=?55), Miscarriage (MI, n?=?142) and Negative Pregnancy (NP, n?=?2034). The effects of ovarian stimulation, laboratory data and seminal parameters on pregnancy outcomes were evaluated using adjusted general linear models. Discriminant analyses were conducted to construct a model for pregnancy prediction and to establish cut-offs for BP. The total sperm count (p?=?0.035), total and progressive sperm motility (p?=?0.001 and p?=?0.023, respectively), total motile sperm count (TMSC, p?=?0.029) and the endometrial thickness (p?<?0.001) were lower among BP group cycles. Lower rates of high-quality cleavage-stage embryos were observed in the BP group compared to CP and MI groups (p?<?0.001). In discriminant analyses, cut-offs for BP prediction were established for the following factors: endometrial thickness < 11?mm, sperm motility < 55.5% and total dose of follicle-stimulating hormone (FSH)> 2400 IU. The incidence of biochemical pregnancy was four times higher when the aforementioned factors did not meet the defined cut-offs. The combination of suboptimal endometrial development and poor seminal and embryo quality contribute to an increased incidence of biochemical pregnancy in ICSI cycles. 相似文献
178.
179.
Paulo Vítor Soeiro-Pereira Angela Falcai Christina Arslanian Kubo Edson Antunes Antonio Condino-Neto 《Memórias do Instituto Oswaldo Cruz》2015,110(1):75-85
In our previous study, we have found that
5-cyclopropyl-2-[1-(2-fluoro-benzyl)-1H-pyrazolo[3,4-b]pyridine-3-yl]-pyrimidin-4-ylamine
(BAY 41-2272), a guanylate cyclase agonist, activates human monocytes and the THP-1
cell line to produce the superoxide anion, increasing in vitro microbicidal activity,
suggesting that this drug can be used to modulate immune functioning in primary
immunodeficiency patients. In the present work, we investigated the potential of the
in vivo administration of BAY 41-2272 for the treatment of Candida albicans and
Staphylococcus aureus infections introduced via intraperitoneal and subcutaneous
inoculation. We found that intraperitoneal treatment with BAY 41-2272 markedly
increased macrophage-dependent cell influx to the peritoneum in addition to
macrophage functions, such as spreading, zymosan particle phagocytosis and nitric
oxide and phorbol myristate acetate-stimulated hydrogen peroxide production.
Treatment with BAY 41-2272 was highly effective in reducing the death rate due to
intraperitoneal inoculation of C. albicans, but not S. aureus. However, we found that
in vitro stimulation of peritoneal macrophages with BAY 41-2272 markedly increased
microbicidal activities against both pathogens. Our results show that the prevention
of death by the treatment of C. albicans-infected mice with BAY 41-2272 might occur
primarily by the modulation of the host immune response through macrophage
activation. 相似文献
180.
Pedro Serra Seyed M. Bani Hashemian Carmen Fagoaga Juan Romero Susana Ruiz-Ruiz Maria T. Gorris Edson Bertolini Núria Duran-Vila 《Journal of virology》2014,88(2):1394-1397
An assay to identify interactions between Citrus Dwarfing Viroid (CDVd) and Citrus Tristeza Virus (CTV) showed that viroid titer was enhanced by the coinfecting CTV in Mexican lime but not in etrog citron. Since CTV encodes three RNA silencing suppressors (RSSs), p23, p20 and p25, an assay using transgenic Mexican limes expressing each RSS revealed that p23 and, to a lesser extent, p25 recapitulated the effect observed with coinfections of CTV and CDVd. 相似文献