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11.
Neil J. Grimsey Berenice Aguilar Thomas H. Smith Phillip Le Amanda L. Soohoo Manojkumar A. Puthenveedu Victor Nizet JoAnn Trejo 《The Journal of cell biology》2015,210(7):1117-1131
Protease-activated receptor 1 (PAR1) is a G protein–coupled receptor (GPCR) for thrombin and promotes inflammatory responses through multiple pathways including p38 mitogen-activated protein kinase signaling. The mechanisms that govern PAR1-induced p38 activation remain unclear. Here, we define an atypical ubiquitin-dependent pathway for p38 activation used by PAR1 that regulates endothelial barrier permeability. Activated PAR1 K63-linked ubiquitination is mediated by the NEDD4-2 E3 ubiquitin ligase and initiated recruitment of transforming growth factor-β–activated protein kinase-1 binding protein-2 (TAB2). The ubiquitin-binding domain of TAB2 was essential for recruitment to PAR1-containing endosomes. TAB2 associated with TAB1, which induced p38 activation independent of MKK3 and MKK6. The P2Y1 purinergic GPCR also stimulated p38 activation via NEDD4-2–mediated ubiquitination and TAB1–TAB2. TAB1–TAB2-dependent p38 activation was critical for PAR1-promoted endothelial barrier permeability in vitro, and p38 signaling was required for PAR1-induced vascular leakage in vivo. These studies define an atypical ubiquitin-mediated signaling pathway used by a subset of GPCRs that regulates endosomal p38 signaling and endothelial barrier disruption. 相似文献
12.
Julian A. Villalba Yushi Liu Mauyuri K. Alvarez Luisana Calderon Merari Canache Gaudymar Cardenas Berenice Del Nogal Howard E. Takiff Jacobus H. De Waard 《PloS one》2013,8(12)
Background
Warao Amerindians, who inhabit the Orinoco Delta, are the second largest indigenous group in Venezuela. High Warao general mortality rates were mentioned in a limited study 21 years ago. However, there have been no comprehensive studies addressing child survival across the entire population.Objectives
To determine the Child Survival-Index (CSI) (ratio: still-living children/total-live births) in the Warao population, the principal causes of childhood death and the socio-demographic factors associated with childhood deaths.Methods
We conducted a cross-sectional epidemiological survey of 688 women from 97 communities in 7 different subregions of the Orinoco Delta. Data collected included socio-demographic characteristics and the reproductive history of each woman surveyed. The multidimensional poverty index (MPI) was used to classify the households as deprived across the three dimensions of the Human Development Index. Multivariable linear regression and Generalized Linear Model Procedures were used to identify socioeconomic and environmental characteristics statistically associated with the CSI.Findings
The average CSI was 73.8% ±26. The two most common causes of death were gastroenteritis/diarrhea (63%) and acute respiratory tract Infection/pneumonia (18%). Deaths in children under five years accounted for 97.3% of childhood deaths, with 54% occurring in the neonatal period or first year of life. Most of the women (95.5%) were classified as multidimensionally poor. The general MPI in the sample was 0.56. CSI was negatively correlated with MPI, maternal age, residence in a traditional dwelling and profession of the head of household other than nurse or teacher.Conclusions
The Warao have a low CSI which is correlated with MPI and maternal age. Infectious diseases are responsible for 85% of childhood deaths. The low socioeconomic development, lack of infrastructure and geographic and cultural isolation suggest that an integrated approach is urgently needed to improve the child survival and overall health of the Warao Amerindians. 相似文献13.
14.
Berenice M. Thomason Patricia P. Harris Karen R. Lewallen Roger M. McKinney 《Current microbiology》1979,2(6):357-360
A polyvalent conjugate forLegionella pneumophila, the Legionnaires’ disease bacterium, was prepared by combining monospecific antibodies for the four recognized serogroups
ofL. pneumophila. Pure cultures ofL. pneumophila and other bacteria representing 18 genera and 50 species of heterologous organisms were used in evaluating the reagent. A
total of 358 specimens from patients suspected of having Legionnaires’ disease also were tested. The results show the practicality
and advantages of using a polyvalentL. pneumophila conjugate for screening clinical specimens. 相似文献
15.
Gabriel Navarrete-Vázquez Sergio Hidalgo-Figueroa Mariana Torres-Piedra Jorge Vergara-Galicia Julio Cesar Rivera-Leyva Samuel Estrada-Soto Ismael León-Rivera Berenice Aguilar-Guardarrama Yolanda Rios-Gómez Rafael Villalobos-Molina Maximiliano Ibarra-Barajas 《Bioorganic & medicinal chemistry》2010,18(11):3985-3991
A series of 1H-benzo[d]imidazole analogues of Pimobendan, substituted at position 5 with either –CF3 or –NO2, were synthesized using a short synthetic route. All the nitro derivatives were potent, and exhibited a concentration- and partial endothelium-dependent vasorelaxant effects, with EC50s <5 μM. 2-Methoxy-4-[5-nitro-1H-benzo[d]imidazol-2-yl]phenol (compound 13) was the most potent derivative of the series, showing an EC50 value of 1.81 μM and Emax of 91.7% for ex vivo relaxant response in intact aortic rings, resulting in a 2.5-fold higher activity compared to Pimobendan. The closely related 5-CF3 analogue (compound 8), was 19 times less potent than 13. The antihypertensive activity of compound 13 was evaluated at doses of 25, 50 and 100 mg kg?1, using spontaneously hypertensive rats (SHR), showing a statistically significant dose-dependent effect. 相似文献
16.
Silva EG Slhessarenko N Arnhold IJ Batista MC Estefan V Osorio MG Marui S Mendonca BB 《Hormone research》2003,59(5):229-233
OBJECTIVE: To establish the cut-off values of GH measured by immunofluorometric assay, a more sensitive and specific assay, in normal prepubertal children and compare their values with those of proven GH-deficient patients. METHODS: 30 normal children (20 males) and 26 patients with known causes of GH deficiency were submitted to the clonidine test and their GH values were compared. A powdered clonidine tablet (0.1 mg/m(2)) was given orally and blood samples for GH measurements were drawn at times -30, 0, 60, 90 and 120 min. RESULTS: GH peak values presented a wide variation ranging from 1.7 to 25 micro g/l (mean +/- SD = 12.87 +/- 5.8 micro g/l) in the normal group. The cut-off values for the 5th and 10th percentiles of the distribution curve were 3.3 and 5.5 micro g/l, respectively. In the GH deficiency group, maximum GH levels after clonidine stimulation ranged from <0.1 to 2.1 micro g/l (0.56 +/- 0.58 micro g/l). CONCLUSIONS: The cut-off values obtained with the immunofluorometric method are lower than the ones obtained by radioimmunoassay. We suggest a cut-off value of 3.3 micro g/l (5th percentile) that ensures 100% of sensitivity along with 93% of specificity to exclude the diagnosis of GH deficiency when using this immunofluorometric method. 相似文献
17.
Dalia Berenice Borbón-Palomares Flora Laborin-Sivirian Clara Tinoco-Ojanguren M. Cristina Peñalba Ivonne Reyes-Ortega Francisco Molina-Freaner 《Plant Ecology》2018,219(8):927-939
Agave colorata is a paniculate agave distributed along the migratory route of the nectar-feeding bat Leptonycteris yerbabuenae. In this paper, we evaluate the importance of nectar-feeding bats in the reproduction of A. colorata in a population in Sonora, Mexico, and describe the germination consequences of self-pollination. We estimated abundance using five plots and set pollination treatments to evaluate the importance of bats. We recorded 14.8?±?6.8 plants/400 m2, with a bimodal size distribution. Flowers are protandrous and visited mainly (>?20 visits/plant/30 min) by L. yerbabuenae. Pollination exclusion experiments showed that flowers excluded from diurnal visitors had maximum fruit set values (0.49?±?0.42), while the autonomous self-pollination treatment had the lowest value (0.03?±?0.06). Similarly, the greatest number of viable seeds per fruit was recorded in the diurnal exclusion treatment, while the greatest number of empty seeds was observed in the self-pollination treatment. Fruit set values among untreated plants varied from 32 to 54%, with a mean value of 41.8%. Seeds derived from self-pollination had a narrower window of opportunity for germination compared to seeds derived from nocturnal pollination. Self-pollinated seeds had lower germination, rate of germination or lag time in response to light, osmotic potential and heat shock treatments, compared to other pollination treatments, revealing an inbreeding cost. Overall, our results show that L. yerbabuenae is the likely major pollinator of the studied A. colorata population. However, under pollinator limitation A. colorata may produce seeds by autonomous self-pollination, at a cost expressed as lower germination. 相似文献
18.
Karla Berenice Carrazco-Peña Katia Farías-Moreno Benjamín Trujillo-Hernández 《Revista espa?ola de geriatría y gerontología》2018,53(1):23-25
Objective
To determine the frequency of successful aging (SA) and its relationship with frailty in an elderly population.Material and methods
An analytical cross-sectional study of subjects ≥60 years of age seen as outpatients in a general hospital. Successful aging was defined as scores of ≥ 90 in the Barthel index and ≤ 2 in the Pfeiffer test. Frailty was determined using the Fried criteria.Results
The study included 400 subjects (272 women and 128 men), with a mean age of 71.6 ± 8.2 years. The SA frequency was 40.4%. frail status was statistically higher in non-successful aging subjects than in SA subjects (161.7 versus 7.9%; P<.001). Women were more frequently frail, while being a pensioner/retired and married were associated less frequently with frailty.Conclusions
Successful aging is associated with a lower level of frailty. 相似文献19.
20.
Gong KW Zhao W Li N Barajas B Kleinman M Sioutas C Horvath S Lusis AJ Nel A Araujo JA 《Genome biology》2007,8(7):R149