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91.
Vassilakopoulos T Govindaraju K Parthenis D Eidelman DH Watanabe Y Hussain SN 《American journal of physiology. Lung cellular and molecular physiology》2007,292(4):L1013-L1022
The effect of muscle activation on muscle nitric oxide (NO) production remains controversial. Whereas NO release increases in in vitro activated muscles and in vivo limb muscles, diaphragmatic NO synthase (NOS) activity declines after 3 h of inspiratory resistive loading (IRL). We tested in this study the hypotheses that acute IRL decreases diaphragmatic NO derivatives levels and reduces protein expression of neuronal (nNOS), endothelial (eNOS), and inducible (iNOS) NO synthases, as well as 3-nitrotyrosine formation. Anesthetized, tracheostomized, spontaneously breathing adult rats were subjected to IRL (50% of the maximum inspiratory pressure) for 1, 3, or 6 h. Quietly breathing rats served as controls. After 3 h of IRL, muscle eNOS and nNOS protein levels rose by 80 and 60% of control values, respectively. Whereas eNOS expression did not change any further, nNOS expression reached 550% of control values after 6 h of IRL. Strong iNOS protein expression was detected in the diaphragms after 6 h of IRL. Total NO derivatives levels in the diaphragm declined during IRL as a result of reduction in nitrate, nitrite, and nitrosothiols. Diaphragmatic protein tyrosine nitration decreased in response to IRL, and this reduction was mainly due to reduced tyrosine nitration of enolase and aldolase. We conclude that diaphragmatic NO derivatives levels decline in response to IRL and that the rise in diaphragmatic NOS protein expression may be a compensatory response designed to counterbalance the decline in NOS activity. 相似文献
92.
Fani Koukouli Ioannis Paspaltsis Evgenia Salta Konstantinos Xanthopoulos Eftychia N. Koini Theodora Calogeropoulou Theodoros Sklaviadis 《朊病毒》2012,6(5):470-476
Prion diseases are fatal, neurodegenerative diseases characterized by the structural conversion of the normal, cellular prion protein, PrPC into an abnormally structured, aggregated and partially protease-resistant isoform, termed PrPSc. Although substantial research has been directed toward development of therapeutics targeting prions, there is still no curative treatment for the disease. Benzoxazines are bicyclic heterocyclic compounds possessing several pharmaceutically important properties, including neuroprotection and reactive oxygen species scavenging. In an effort to identify novel inhibitors of prion formation, several 5,7,8-trimethyl-1,4-benzoxazine derivatives were evaluated in vitro for their effectiveness on the expression levels of normal PrPC and its conversion to the abnormal isoforms of PrPSc in a scrapie-infected cell culture model. The most potent compound was 2-(4-methoxyphenyl)-5,7,8-trimethyl-3,4-dihydro-2H-1,4-benzoxazine, with a diminishing effect on the formation of PrPSc, thus establishing a class of compounds with a promising therapeutic use against prion diseases. 相似文献
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95.
Vassiliki Kati Konstantina Zografou Elli Tzirkalli Theodoros Chitos Luc Willemse 《Journal of Insect Conservation》2012,16(6):807-818
The present paper studies butterfly, grasshopper and vascular plant communities in ten seasonally flooded grasslands with different anthropogenic disturbance regimes (NW Greece). Disturbance intensity was assessed on the basis of disturbance frequency and type (grazing, mowing, trampling, constructions). The distribution patterns of butterflies are regulated by humidity and elevation (Redundancy Analysis). Elevation, flower-heads abundance, low disturbance intensity and plant species richness predict grasshopper species richness well, while the latter together with humidity predict plant species richness (Generalized Linear Models). Chorthippus lacustris, a critically endangered endemic grasshopper species, is positively associated with humid microhabitats with high flower-heads abundance. An indicator value procedure reveals four butterfly species as being typical species for habitats with a pronounced character of hedgerows and tree lines. Conservation management of grassland butterflies should focus on the maintenance of the humid character of the humid grasslands as well as on the maintenance of hedgerows and tree lines. The reduction of human-induced disturbance towards occasional grazing and mowing seems to benefit both butterfly and grasshopper communities. Finally, we suggest the use of grasshoppers as surrogates for vascular plants and vice versa, given their congruent species richness patterns. 相似文献
96.
Sergentanis TN Economopoulos KP Choussein S Vlahos NF 《Molecular biology reports》2012,39(6):6647-6654
This meta-analysis aims to examine whether the genotype status of MspI and Ile462Val polymorphisms in Cytochrome-P450 1A1
(CYP1A1) is associated with cervical cancer risk. Eligible case-control studies were identified through search in MEDLINE
(end of search: October 2010). Pooled odds ratios (ORs) were appropriately derived from fixed-effects or random effects models.
Concerning MspI polymorphism, six studies were eligible (722 cases and 770 controls); four studies were eligible (350 cases
and 519 controls) for Ile462Val. MspI polymorphism was associated with elevated cervical cancer risk (for heterozygous TC
vs. TT carriers OR = 1.50, 95% CI: 0.93–2.42, random effects; for homozygous CC vs. TT carriers OR = 2.66, 95% CI: 1.14–6.19,
random effects). Similarly, Ile462Val polymorphism was associated with elevated cervical cancer risk (for heterozygous Ile/Val
vs. Ile/Ile carriers OR = 2.36, 95% CI: 1.10–5.08, random effects; for homozygous Val/Val vs. Ile/Ile carriers OR = 2.73,
95% CI: 1.21–6.15, fixed effects). The results were replicated upon Caucasian subjects, who represented the majority of existing
data. The two examined CYP1A1 genotype polymorphisms seem to confer additional risk for cervical cancer. Accumulation of further
data seems mandatory for future race-specific analyses and for the demonstration of CYP1A1-smoking interactions. 相似文献
97.
Flora Zagouri Theodoros N. Sergentanis Maria Gazouli Alexandra Tsigginou Constantine Dimitrakakis Irene Papaspyrou Evaggelos Eleutherakis-Papaiakovou Dimosthenis Chrysikos George Theodoropoulos George C. Zografos Aris Antsaklis Athanassios-Meletios Dimopoulos Christos A. Papadimitriou 《Molecular biology reports》2012,39(12):10873-10879
This case control study aims to investigate the role of HSP90 Gln488His (C?>?G), HSP70-2 P1/P2, HIF-1 alpha C1772T and HSPA8 intronic 1541–1542delGT polymorphisms as potential risk factors and/or prognostic markers for breast cancer. 113 consecutive incident cases of histologically confirmed ductal breast cancer and 124 healthy cases were recruited. The above mentioned polymorphisms were genotyped; multivariate logistic regression was performed. HSP90 GG (His/His) genotype was associated with elevated breast cancer risk. Similarly, the allele dose–response model pointed to increase in breast cancer risk per G allele. HSP70-2 P1/P2, HSPA8 intronic 1541–1542delGT and HIF-1 alpha polymorphisms were not associated with breast cancer risk, as evidenced by the dose–response allele models. The positive association between HSP90 G allele and breast cancer risk seemed to pertain to both premenopausal and postmenopausal women. With respect to survival analysis, none of the aforementioned polymorphisms was associated with either disease-free survival or overall survival. HSP90α Gln488His polymorphism seems to be a risk factor for breast cancer. On the other hand, our study did not point to excess risk conferred by HSPA8 1541–1542delGT, Hsp70-2 P1/P2 and HIF-1α C1772T. 相似文献
98.
Chochlakis D Ioannou I Sandalakis V Dimitriou T Kassinis N Papadopoulos B Tselentis Y Psaroulaki A 《Microbial ecology》2012,63(2):314-323
In two surveys conducted from March 1999 to March 2001 and from January 2004 to December 2006, a total of 3,950 ticks (belonging
to ten different species) were collected from seven domestic and wild animals (goat, sheep, cattle, dog, fox, hare, and mouflon)
from different localities throughout Cyprus. In order to establish their infection rate with Spotted Fever Rickettsiae (SFG), ticks were pooled and tested by polymerase chain reaction targeting gltA and ompA genes, followed by sequencing analysis. When tick pools tested positive, individual ticks were then tested one by one, and
of the 3,950 ticks screened, rickettsial DNA was identified in 315 ticks (infection rate, 8%). Five SFG Rickettsiae were identified: Rickettsia aeschlimannii in Hyalomma marginatum marginatum, Rickettsia massiliae in Rhipicephalus turanicus and Rhipicephalus sanguineus, Rickettsia sibirica mongolotimonae in Hyalomma anatolicum excavatum, and a Rickettsia endosymbiont of Haemaphysalis sulcata (later described as Rickettsia hoogstraalii) in Haemaphysalis punctata. Two additional genes, 17 kDa and ompB, were targeted to characterize a new genotype of “Candidatus Rickettsia barbariae” genotype in R. turanicus, designated here as “Candidatus Rickettsia barbariae” Cretocypriensis. These results confirm the presence of a spectrum of SFG Rickettsiae on the island. Further studies are necessary to gain better knowledge on the epidemiology of SFG Rickettsiae in Cyprus. 相似文献
99.
ABSTRACT: Idiopathic scoliosis, a common disorder of lateral displacement and rotation of vertebral bodies during periods of rapid somatic growth, has many effects on respiratory function. Scoliosis results in a restrictive lung disease with a multifactorial decrease in lung volumes, displaces the intrathoracic organs, impedes on the movement of ribs and affects the mechanics of the respiratory muscles. Scoliosis decreases the chest wall as well as the lung compliance and results in increased work of breathing at rest, during exercise and sleep. Pulmonary hypertension and respiratory failure may develop in severe disease. In this review the epidemiological and anatomical aspects of idiopathic scoliosis are noted, the pathophysiology and effects of idiopathic scoliosis on respiratory function are described, the pulmonary function testing including lung volumes, respiratory flow rates and airway resistance, chest wall movements, regional ventilation and perfusion, blood gases, response to exercise and sleep studies are presented. Preoperative pulmonary function testing required, as well as the effects of various surgical approaches on respiratory function are also discussed. 相似文献
100.
Negrini S Aulisa AG Aulisa L Circo AB de Mauroy JC Durmala J Grivas TB Knott P Kotwicki T Maruyama T Minozzi S O'Brien JP Papadopoulos D Rigo M Rivard CH Romano M Wynne JH Villagrasa M Weiss HR Zaina F 《Scoliosis》2012,7(1):1-35