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191.
Arnon D. Jurberg Tiana Gonçalves Tatiane A. Costa Ana Carolina A. de Mattos Bernardo M. Pascarelli Pedro Paulo A. de Manso Marcelo Ribeiro-Alves Marcelo Pelajo-Machado José M. Peralta Paulo Marcos Z. Coelho Henrique L. Lenzi 《Development genes and evolution》2009,219(5):219-234
Schistosomiasis is a water-borne parasitic illness caused by neoophoran trematodes of the genus Schistosoma. Using classical histological techniques and whole-mount preparations, the present work describes the embryonic development
of Schistosoma mansoni eggs in the murine host and compares it with eggs maintained under in vitro conditions. Two pre-embryonic stages occur inside
the female worm: the prezygotic stage is characterized by the release of mature oocytes from the female ovary until its fertilization.
The zygotic stage encompasses the migration of the zygote through the ootype, where the eggshell is formed, to the uterus.
Fully formed eggs are laid still undeveloped, without having suffered any cleavage. In the outside environment, eight embryonic
stages can be defined: stage 1 refers to early cleavages and the beginning of yolk fusion. Stage 2 represents late cleavage,
with the formation of a stereoblastula and the onset of outer envelope differentiation. Stage 3 is defined by the elongation
of the embryonic primordium and the onset of inner envelope formation. At stage 4, the first organ primordia arise. During
stages 5 to 7, tissue and organ differentiation occurs (neural mass, epidermis, terebratorium, musculature, and miracidial
glands). Stage 7 is characterized by the nuclear condensation of neurons of the central neural mass. Stage 8 refers to the
fully formed larva, presenting muscular contraction, cilia, and flame-cell beating. This staging system was compared to a
previous classification and could underlie further studies on egg histoproteomics (morphological localizome). The differentiation
of embryonic structures and their probable roles in granulomatogenesis are discussed herein.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
192.
Andréa F.S. Santos Luciana A. Luz Adriana C.C. Argolo José A. Teixeira Patrıícia M.G. Paiva Luana C.B.B. Coelho 《Process Biochemistry》2009,44(4):504-508
In this work hemagglutinating activity (HA) was investigated in distinct Moringa oleifera tissue extracts. A new lectin from seeds (cMoL) was purified and characterized; hemagglutinating and coagulating activities were evaluated. HA was detected in 0.15 M NaCl extracts from flowers and rachis inflorescence (5%, w/v), seeds, leaves, fundamental tissue of stem and steam bark (10%, w/v). cMoL isolated after saline extraction and guar gel column chromatography was active at pH range 4.0–9.0 agglutinating erythrocytes from rabbit and human blood types. Extracts of tissues and cMoL activities were carbohydrate inhibited; azocasein and asialofetuin abolished cMoL HA. The lectin was thermostable at 100 °C during 7 h. Polyacrylamide gel electrophoresis under reduced conditions revealed a main polypeptide band of 26.5 kDa; native basic cMoL was detected as a unique band. Seed lectin preparations and cMoL showed coagulant activity, similar to aluminium sulphate, the coagulant most widely used in water treatment. 相似文献
193.
194.
Individual perception of vaccine safety is an important factor in determining a person's adherence to a vaccination program and its consequences for disease control. This perception, or belief, about the safety of a given vaccine is not a static parameter but a variable subject to environmental influence. To complicate matters, perception of risk (or safety) does not correspond to actual risk. In this paper we propose a way to include the dynamics of such beliefs into a realistic epidemiological model, yielding a more complete depiction of the mechanisms underlying the unraveling of vaccination campaigns. The methodology proposed is based on Bayesian inference and can be extended to model more complex belief systems associated with decision models. We found the method is able to produce behaviors which approximate what has been observed in real vaccine and disease scare situations. The framework presented comprises a set of useful tools for an adequate quantitative representation of a common yet complex public-health issue. These tools include representation of beliefs as Bayesian probabilities, usage of logarithmic pooling to combine probability distributions representing opinions, and usage of natural conjugate priors to efficiently compute the Bayesian posterior. This approach allowed a comprehensive treatment of the uncertainty regarding vaccination behavior in a realistic epidemiological model. 相似文献
195.
Caroline M. Ferreira Ana T.M. Pereira Rafael S. de Souza Fernanda M. Coelho Stephen Poole Mauro M. Teixeira Deborah Negrão-Corrêa 《Microbes and infection / Institut Pasteur》2010,12(5):409-414
IL-13 is a cytokine known to play a role in several pulmonary diseases, including asthma and fibrosis. The role of IL-13 in the context of pulmonary changes induced by helminth infection is unclear. Rats experimentally infected with Strongyloides venezuelensis and treated with anti-IL-13 neutralizing antibody were used to evaluate the role of IL-13 on functional and inflammatory changes of host lungs, and on parasite control. S. venezuelensis-induced airway hyperreactivity was IL-13-independent, but IL-13 played an essential role in driving airway mucus production and eosinophil infiltration. IL-13 was important for the control of egg production but not establishment in the intestine. 相似文献
196.
The sequencing of entire genomes has led to the identification of many genes. A future challenge will be to determine the function of all of the genes of an organism. One of the best ways to ascertain function is to disrupt genes and determine the phenotype of the resulting organism. Novel large-scale approaches for generating gene disruptions and analyzing the resulting phenotype are underway in the budding yeast Saccharomyces cerevisiae and other organisms including flies, Mycoplasma, worms, plants and mice. These approaches and mutant collections will be extremely valuable to the scientific community and will dramatically alter the manner in which science is performed in the future. 相似文献
197.
Eduardo Massad Annelies Wilder-Smith Raphael Ximenes Marcos Amaku Luis Fernandez Lopez Francisco Antonio Bezerra Coutinho Giovanini Evelim Coelho Jarbas Barbosa da Silva Jr Claudio José Struchiner Marcelo Nascimento Burattini 《Memórias do Instituto Oswaldo Cruz》2014,109(3):394-397
Brazil will host the FIFA World Cup™, the biggest single-event competition in the
world, from June 12-July 13 2014 in 12 cities. This event will draw an estimated
600,000 international visitors. Brazil is endemic for dengue. Hence, attendees of the
2014 event are theoretically at risk for dengue. We calculated the risk of dengue
acquisition to non-immune international travellers to Brazil, depending on the
football match schedules, considering locations and dates of such matches for June
and July 2014. We estimated the average per-capita risk and expected
number of dengue cases for each host-city and each game schedule chosen based on
reported dengue cases to the Brazilian Ministry of Health for the period between
2010-2013. On the average, the expected number of cases among the 600,000 foreigner
tourists during the World Cup is 33, varying from 3-59. Such risk estimates will not
only benefit individual travellers for adequate pre-travel preparations, but also
provide valuable information for public health professionals and policy makers
worldwide. Furthermore, estimates of dengue cases in international travellers during
the World Cup can help to anticipate the theoretical risk for exportation of dengue
into currently non-infected areas. 相似文献
198.
Luciano Pamplona de Góes Cavalcanti Lia Alves Martins Mota Gustavo Porto Lustosa Mayara Carvalho Fortes Davi Alves Martins Mota Ant?nio Afonso Bezerra Lima Ivo Castelo Branco Coelho Maria Paula Gomes Mour?o 《Memórias do Instituto Oswaldo Cruz》2014,109(1):93-98
In 2009, the World Health Organization (WHO) issued a new guideline that stratifies
dengue-affected patients into severe (SD) and non-severe dengue (NSD) (with or
without warning signs). To evaluate the new recommendations, we completed a
retrospective cross-sectional study of the dengue haemorrhagic fever (DHF) cases
reported during an outbreak in 2011 in northeastern Brazil. We investigated 84
suspected DHF patients, including 45 (53.6%) males and 39 (46.4%) females. The ages
of the patients ranged from five-83 years and the median age was 29. According to the
DHF/dengue shock syndrome classification, 53 (63.1%) patients were classified as
having dengue fever and 31 (36.9%) as having DHF. According to the 2009 WHO
classification, 32 (38.1%) patients were grouped as having NSD [4 (4.8%) without
warning signs and 28 (33.3%) with warning signs] and 52 (61.9%) as having SD. A
better performance of the revised classification in the detection of severe clinical
manifestations allows for an improved detection of patients with SD and may reduce
deaths. The revised classification will not only facilitate effective screening and
patient management, but will also enable the collection of standardised surveillance
data for future epidemiological and clinical studies. 相似文献
199.
Sirlene Souza Rodrigues Sartori Katiane de Oliveira Pinto Coelho Nogueira Alípio dos Santos Rocha Clóvis Andrade Neves 《Acta zoologica》2011,92(2):179-186
Rodrigues Sartori, S. S., Nogueira, K. O. P. C., Rocha, A. S. and Neves, C. A. 2011. Morphology of the stomach of the tropical house gecko Hemidactylus mabouia (Squamata: Gekkonidae). —Acta Zoologica (Stockholm) 92 : 179–186. Hemidactylus mabouia is a common species in Brazil, which facilitates its use in research in several areas and allows display it as a benchmark for studies with reptiles. To study the morphology of the stomach of H. mabouia, we carried out anatomical, histological and histochemical analysis. The stomach of H. mabouia is ‘J’ shaped and can be divided into oral fundic (OF), aboral fundic (AF) and pyloric regions. The surface epithelium is composed of mucosecretory cells (MC) containing neutral mucins. In the lamina propria of the OF region, are large ramified tubulo‐acinar glands, which become smaller, less ramified and more tubular towards the AF region, and are simple tubular and short in the pyloric region. The fundic glands contain differentiated neck and pit. The neck is composed of MC containing neutral mucins and the pit is made of oxyntopeptic cells (OC). The OC of the OF region contained many zymogen granules, while those of the AF region contained few zymogen granules and many mitochondria, which suggests the existence of a gradient of pepsinogen and hydrochloric acid secretion. Pyloric glands consisted of MC containing neutral mucins and both argyrophil and argentaffin endocrine cells. 相似文献
200.
Lactate downregulates the glycolytic enzymes hexokinase and phosphofructokinase in diverse tissues from mice 总被引:1,自引:0,他引:1
Leite TC Coelho RG Da Silva D Coelho WS Marinho-Carvalho MM Sola-Penna M 《FEBS letters》2011,(1):92-98
We examined the effects of lactate on the enzymatic activity of hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) in various mouse tissues. Our results showed that lactate inhibited PFK activity in all the analyzed tissues. This inhibitory effect was observed in skeletal muscle even in the presence of insulin. Lactate directly inhibited the phosphorylation of PFK tyrosine residues in skeletal muscle, an important mechanism of the enzyme activation. Moreover, lactate indirectly inhibited HK activity, which resulted from its cellular redistribution, here attributed to alterations of HK structure. PK activity was not affected by lactate. The activity of HK and PFK is directly related to glucose metabolism. Thus, it is conceivable that lactate exposure can induce inhibition of glucose consumption in tissues. 相似文献