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41.
M Godina 《Plastic and reconstructive surgery》1979,64(5):673-682
In our early clinical experience with free flaps, we used end-to-end arterial anastomoses and in 9 our of 24 we had complete failures--7 of which were due to early arterial thrombosis. Contrarily, in 41 consecutive free flaps with end-to-side anastomoses we have not had a single failure. At the same time that we began using the end-to-side anastomoses, we also began using the latissimus dorsi free flap as our flap of first choice, and we agree that this was probably an additional reason for our improved success rate. The use of end-to-side anastomoses has the following advantages: (1) a high success rate; (2) preservation of all existing vessels in an injured extremity; (3) greater freedom of operative planning; and (4) technical simplicity in terms of access to the vessels. For us, these advantages have made end-to-side anastomosis the technique of choice in the transfer of free flaps. 相似文献
42.
V.DE LA FUENTE E. ORTÜÑEZ 《Botanical journal of the Linnean Society. Linnean Society of London》1994,114(1):23-30
A new species of Festuca (Festuca rivas-martinezii de la Fuente & Ortúñez) is described from the Sierra de Ayllón, Sierra de Guadarrama, Sierra de Gredos and associated chains (northcentral Spain: provinces of Avila, Guadalajara, Madrid and Segovia. Some morphological, anatomical and cytological characters of the taxon are presented. 相似文献
43.
M Godina 《Plastic and reconstructive surgery》1987,80(2):304-306
A technique is described for dissection of the latissimus dorsi free flap which yields musculocutaneous cover accurately tailored to the primary defect. It involves exposure high into the axilla, early transverse incision of the muscle to enhance visualization of the pedicle, and transection of the muscle close to the point at which the thoracodorsal artery enters. This last step eliminates the bulky portion of the muscle between this point of vascular supply and its insertion. 相似文献
44.
RICHARD P. BROWN R. S. THORPE M. BÁEZ 《Biological journal of the Linnean Society. Linnean Society of London》1993,50(4):313-328
Recent studies indicate that differential selection between mesic and xeric habitats is the most plausible explanation of within-island geographic variation in the Gran Ganarian skink, Chalcides sexlineatus. The island of Tenerife shows mesic/xeric heterogeneity similar to that on Gran Canaria, so we tested the prediction of parallel geographic patterns of morphological population differentiation in the Tenerife skink, Chalcides viridanus. Geographic variation was found to be complex; patterns of differentiation in body dimensions and scalation show evidence of both mosaic and latitudinal facets. Using randomization and regression methods, significant relationships were found between a hypothesized xeric/mesic model of population differentiation and geographic variation in female body dimensions, as well as with substantial proportions of the geographic variation in male and female scalation and, to a lesser extent, body dimensions. Matrix comparisons based on the entire morphological distance matrices show that the patterns of variation are not concordant with an alternative hypothesis of historical secondary contact, or with an isolation-by-distance model. It is argued that a substantial component of the geographic variation in body dimensions and scalation of C. viridanus is due to differential selection along an aridity gradient. 相似文献
45.
YADVINDER MALHI DANIEL WOOD TIMOTHY R. BAKER JAMES WRIGHT OLIVER L. PHILLIPS THOMAS COCHRANE PATRICK MEIR JEROME CHAVE SAMUEL ALMEIDA LUZMILLA ARROYO NIRO HIGUCHI TIMOTHY J. KILLEEN SUSAN G. LAURANCE WILLIAM F. LAURANCE SIMON L. LEWIS ABEL MONTEAGUDO DAVID A. NEILL PERCY NÚÑEZ VARGAS NIGEL C. A. PITMAN CARLOS ALBERTO QUESADA RAFAEL SALOMÃO JOSÉ NATALINO M. SILVA ARMANDO TORRES LEZAMA JOHN TERBORGH RODOLFO VÁSQUEZ MARTÍNEZ BARBARA VINCETI 《Global Change Biology》2006,12(7):1107-1138
The biomass of tropical forests plays an important role in the global carbon cycle, both as a dynamic reservoir of carbon, and as a source of carbon dioxide to the atmosphere in areas undergoing deforestation. However, the absolute magnitude and environmental determinants of tropical forest biomass are still poorly understood. Here, we present a new synthesis and interpolation of the basal area and aboveground live biomass of old‐growth lowland tropical forests across South America, based on data from 227 forest plots, many previously unpublished. Forest biomass was analyzed in terms of two uncorrelated factors: basal area and mean wood density. Basal area is strongly affected by local landscape factors, but is relatively invariant at regional scale in moist tropical forests, and declines significantly at the dry periphery of the forest zone. Mean wood density is inversely correlated with forest dynamics, being lower in the dynamic forests of western Amazonia and high in the slow‐growing forests of eastern Amazonia. The combination of these two factors results in biomass being highest in the moderately seasonal, slow growing forests of central Amazonia and the Guyanas (up to 350 Mg dry weight ha?1) and declining to 200–250 Mg dry weight ha?1 at the western, southern and eastern margins. Overall, we estimate the total aboveground live biomass of intact Amazonian rainforests (area 5.76 × 106 km2 in 2000) to be 93±23 Pg C, taking into account lianas and small trees. Including dead biomass and belowground biomass would increase this value by approximately 10% and 21%, respectively, but the spatial variation of these additional terms still needs to be quantified. 相似文献
46.
R. PANADERO G. VARAS G. PAJARES F. MARKINA C. LÓPEZ P. DÍAZ A. PÉREZ‐CREO A. PRIETO P. DÍEZ‐BAÑOS P. MORRONDO 《Medical and veterinary entomology》2017,31(1):94-96
Subcutaneous larvae of Hypoderma spp. (Diptera: Oestridae) were detected in the dorsal region in 10 roe deer, Capreolus capreolus (Artiodactyla: Cervidae), hunted in central Spain between January and March 2016. All larvae were found in the inner side of the hide during the skinning of the animals. The study of the morphological features of eight larvae of different stages collected from two animals allowed the identification of Hypoderma actaeon Brauer. The small size (4–5 mm) of some of the first instars suggests that the internal lifecycle of H. actaeon may be exclusively subcutaneous. This is the first confirmation of H. actaeon in roe deer; however, further studies to assess the spread of the parasite and to follow the evolution of this myiasis in roe deer are needed. 相似文献
47.
ISOLDA LUNA‐VEGA J. DANIEL TEJERO‐DÍEZ RAÚL CONTRERAS‐MEDINA MICHAEL HEADS GERARDO RIVAS 《Biological journal of the Linnean Society. Linnean Society of London》2012,106(4):940-955
We analyzed the geographical and elevational distributions of two Polypodium complexes from Mexico and Central America. Distribution data of nine species of the Polypodium colpodes complex and the Polypodium plesiosorum complex were obtained from almost 1500 herbarium specimens, field collections in Mexico and Costa Rica, and literature studies. The presence of each species was recorded for each Mesoamerican country, in 1° × 1° grid‐cells and biogeographical provinces. The rarity of species was also evaluated. Although the two complexes show extensive overlap, the P. colpodes complex is distributed mainly along the Pacific versant of Mexico and Central America, whereas the P. plesiosorum complex occurs mainly along the Atlantic versant. Those biogeographical provinces with maximum species diversity are Chiapas (seven species), Sierra Madre del Sur (six species), and the Trans‐Mexican Volcanic belt (six species). Grid‐cells with more species are located mainly in the mountains of central‐southern Mexico and northern Central America. Richness does not decrease or increase with latitude. Elevation distributions showed that most Polypodium species are concentrated in the montane interval and three species groups were recognized based on elevational preferences. Polypodium colpodes and P. plesiosorum are the most widely distributed species, whereas Polypodium castaneum and Polypodium flagellare are the only two species that possess the three attributes of rarity (narrow geographical distribution, high habitat specificity, and scarce local populations). Polypodium species of both complexes are present mainly in the montane regions of the study area and show some degree of geographical sympatry, especially in southern Mexico and northern Central America. This overlapping is explained by the elevation tolerance within montane systems and because most species inhabit three or more vegetation types. The distributional patterns of these complexes coincided with the three regional highlands of Mesoamerica, which are separated from each other by the Isthmus of Tehuantepec and by the lowlands of Nicaragua. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ?? , ??–??. 相似文献
48.
P. CRUZ B. Y
EZ‐JACOME A. M. IBARRA J. RANGEL‐BECERRIL 《Molecular ecology resources》2007,7(3):448-450
Microsatellite loci were isolated in Crassostrea corteziensis using (GT)n, (CT)n and (CTGT)n‐enriched genomic libraries. Within each of 45 sequenced clones, an average of three microsatellite regions (156 total) were observed. Thirty‐three primers were designed, from which 11 microsatellite loci amplified. Ten of those were polymorphic, with a range of two to 30 alleles. Three loci were not in Hardy–Weinberg equilibrium, and linkage disequilibrium was found for six pairs of loci. These microsatellite loci will be further tested for segregation distortions and null alleles to establish a set for population genetic studies of the species in the Northwest coasts of Mexico, and for optimization of aquaculture development. Seven of the microsatellite loci cross‐amplified in Crassostrea palmula, a sympatric species, and will be useful in further genetic studies. 相似文献
49.
Godina E Khomyakova I Purundzhan A Tretyak A Zadorozhnaya L 《Journal of physiological anthropology》2007,26(2):229-234
The influence of physical activity on body mass components has been studied using a sample of Moscow children. 195 girls and 259 boys of Russian ethnicity from 12 to 17 years old were investigated cross-sectionally in 2005 in different Moscow schools. According to the level of physical activity they were divided into three groups: 1-those who did not take part in regular physical exercise (44 boys and 50 girls); 2-those who took part in special sports programs in general education schools (82 boys and 82 girls); 3-students of special sports schools with a high sports ranking (133 boys and 63 girls). The program included anthropometric measurements, evaluation of sexual maturation indices, somatotypes, and "functional" traits (diastolic and systolic blood pressure, pulse rate, hand grip, etc). For the study of body composition, bioelectrical impedance analysis (BIA) was used. The estimates of body mass components were also calculated using the anthropometric measurements. For the fat component, the estimates obtained by BIA and the anthropometric methods were highly correlated: r=0.85-0.88. Age changes of BIA measurements and body components were analysed. With multiple regression analysis it was shown that BIA measurements are dependent on a great number of morphological and functional traits, with the most informative sets of traits being selected. The degree of physical activity has a strong effect on body components: the contents of fat-free mass (FFM) and total body water (TBW) significantly increase, and the fat mass (FM) in girls decreases. 相似文献
50.
This paper explores the economic viability of producing biofuels from Agave in Mexico and the potential for it to complement the production of tequila or mescal. We focus on Agave varieties currently being used by the tequila industry to produce two beverages, tequila and mescal, and explore the potential for biofuel production from these plants. Without competing directly with beverage production, we discuss the economic costs and benefits of converting Agave by‐products to liquid fuel as an additional value‐added product and expanding cultivation of Agave on available land. We find that the feedstock cost for biofuel from the Agave piña alone could be more than US$3 L?1 on average. This is considerably higher than the feedstock costs of corn ethanol and sugarcane ethanol. However, there may be potential to reduce these costs with higher conversion efficiencies or by using sugar present in other parts of the plant. The costs of cellulosic biofuels using the biomass from the entire plant could be lower depending on the conversion efficiency of biomass to fuel and the additional costs of harvesting, collecting and transporting that biomass. 相似文献