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131.
Growth of juvenile American lobsters, Homarus americanus , raised in four semiopen culture systems, with daily water exchange rates ranging from 29 percent to 3.3 percent, was compared with growth in a completely closed system. Animals were fed a formulated pelleted ration, water quality factors were measured daily, and changes in concentration of nitrate, orthophosphate, and total organic carbon were monitored. Results of two 90-day trials indicate that growth increased in the system with the lower water exchange rates. Maximum growth occurred in the closed system. 相似文献
132.
A general survey of the information presently available on the osteology and myology of the hyobranchial apparatus. Included in the survey are examples of the hyobranchial skeleton of the major groups of reptiles, including the Chelonia, Crocodilia, Rhynchocephalia, and Squamata. The myology treats the muscles directly associated with the hyoid as well as those associated with the functioning of the apparatus, but not arising or inserted directly on or from the hyoid. The innervation of the hyobranchial apparatus is reviewed and briefly discussed based on the information available in a few major studies. An attempt is made to cite all pertinent literature references, and in Tables 1 and 2 the references to basic areas are indicated. Twenty - nine plates and figures are included, some of which represent original research. 相似文献
133.
This report includes data collected during an investigation by Brigham Young University personnel from 1971 to 1976, as well as a literature review. The fauna of the Kaiparowits Basin is represented by 7 species of amphibians (1 salamander, 5 toads, and 1 tree frog), 29 species of reptiles (1 turtle, 16 lizards, and 12 snakes), 183 species of birds (plus 2 hypothetical), and 74 species of mammals. Geographic distribution of the various species within the basin are discussed. Birds are categorized according to their population and seasonal status. Avian habitat relationships are discussed, and extensions of range are reported for 5 species of birds. Three threatened or endangered avian species occur in the basin. Four avian species seem to have declined significantly in numbers in recent years. 相似文献
134.
Thirty-nine previously unpublished reports of the endangered black-footed ferret from Wyoming are listed with dates, locations, number of animals, sources, and comments. 相似文献
135.
The skeleton of a young American black bear ( Ursus americanus ) possessing asymmetrical distortions of the 5 caudalmost lumbar neural spines was recovered from west Texas. We attribute this abnormality, presumed to be congenital, to the absence or atrophy of the right multifidus muscle straddling L3 and to the series of compensatory muscle adjustments required to maintain spinal alignment. This finding may have important management implications for black bears in Texas, given the possibility that our specimen originates from a partially isolated population. El esqueleto de un oso negro juvenil ( Ursus americanus ) con distorsiones asimétricas de las cinco espinas neurales lumbares inferiores fue descubierto en el oeste de Texas. Atribuimos esta anormalidad, suponiendo que es de origen congénito, a la ausencia o atrofia del músculo multifidus derecho que se extiende a ambos lados de la vértebra L3 y la serie de ajustes musculares compensatorios necesarios para conservar el alineamiento espinal. Este hallazgo podría tener implicaciones importantes para esta especie en Texas, dada la posibilidad de que nuestro espécimen provenga de una población parcialmente aislada. 相似文献
136.
Normal 0 false false false MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} To examine the partitioning of genetic variation within the Mexican vole ( Microtus mexicanus ), we analyzed variation within the cytochrome b (cyt b, ca. 953 bp) from 44 samples of the Mexican vole from the mountains of the southwestern United States and Mexico. Phylogeographic analyses demonstrated strong support for a western clade and an eastern clade, corresponding to the Sierra Madre Occidental and mountains of the southwestern United States (western clade) and the Sierra Madre Oriental and the Sierra Madre del Sur (eastern clade). Levels of genetic distinctiveness among vole populations in Mexico and the southwestern United States support recognition of the Mogollon vole ( Microtus mogollonensis ). Estimates of lineage divergence suggested an older divergence for populations in Mexico and a more recent divergence for the presumptive M. mogollonensis. Ecological analyses demonstrated a distinct climate niche between vole lineages in the Southwest and Mexico, which indicated the possible role of environmental variation in diversification of the Mexican vole. A similar pattern of climatic separation was also demonstrated between clades of the codistributed taxa Sigmodon hispidus, Neotoma mexicana, and Peromyscus truei, suggesting a broader role for climatic variation in the origin and maintenance of the region’s biodiversity. Para examinar la distribución de la variación genética en el metorito mexicano, analizamos la variación en el citocromo b (cyt b, c. 953 pb ) en 44 muestras del metorito mexicano de las montañas de México y del suroeste de Estados Unidos. Los análisis filogeográficos demostraron fuerte apoyo para un clado occidental y un clado oriental, correspondientes a la Sierra Madre Occidental y las montañas del suroeste de Estados Unidos (oeste) y la Sierra Madre Oriental y la Sierra Madre del Sur (este). Los niveles de diferencia genética entre las poblaciones de metoritos en México y las del sur de Estados Unidos apoyan el reconocimiento del metorito Mogollon ( Microtus mogollonensis ) como especie. Las estimaciones de divergencia entre linajes indican una divergencia más remota para las poblaciones en México y una más reciente para el presunto M. mogollonensis. Los análisis ecológicos demuestran nichos climáticos distintos entre los linajes de metorito en el suroeste de Estados Unidos y en México, lo cual indica el posible papel de la variación ambiental en la diversificación del metorito mexicano. Un patrón similar de separación climática fue también demostrado entre clados de los taxones codistribuidos: Sigmodon hispidus, Neotoma mexicana y Peromysus truei, sugiriendo que la variación climática tiene un mayor papel en el origen y el mantenimiento de la biodiversidad de la región. 相似文献
137.
The White-faced Ibis ( Plegadis chihi ) is a California state and U.S. Fish and Wildlife Service species of special management concern. We studied White-faced Ibis breeding ecology from May through July 1995 on Lower Klamath National Wildlife Refuge (NWR) in the upper Klamath Basin of California. A total of 2029 pairs nested in 3 colonies exclusively in early-successional hardstem bulrush ( Scirpus acutus ). Nest initiation dates ranged from 10 May to 12 June, and mean clutch size was 3.16. Reproductive success averaged 87% apparent nest success ( n = 115), 82% hatchability, 97% whole and partial brood survival, and 2.39 fledglings per successful nest. Mayfield estimates of nest survival were 79.1% during the laying and incubation period and 95% during the nestling period. Overall nest success as estimated by the Mayfield method was 75.4%. Our estimates of nest success are some of the highest reported anywhere in the literature for White-faced Ibis. Therefore, Lower Klamath NWR may maintain preferred White-faced Ibis breeding habitats in years of otherwise poor habitat conditions across the Intermountain West. 相似文献
138.
A review of the distribution of Rhinocheilus l. lecontei, in Utah, with a northward extension of its range in the Upper Colorado River Basin. 相似文献
139.
Fertilized ova of razorback sucker, Xyrauchen texanus, were adhesive for 3 to 4 hours after fertilization. Cleavage was completed at 24 hours, gastrulation occurred at 34 hours, and blood circulation was established at 117 hours. Hatching occurred from 5.2 to 5.5 days after fertilization. Larvae were from 6.8 to 7.3 mm TL at hatching. Yolk was assimilated at 13 days (10 mm TL). All fins were formed and had ossified rays at 64 days (27 mm TL). The unique nuchal keel appeared about 200 days after fertilization. 相似文献
140.
Wilmer W. Tanner 《西北部美国博物学家》2011,44(1)
For about 20 years Richard P. Erwin collected amphibians and reptiles in southwestern Idaho. This report is an attempt to indicate some of his herpetological activities, and to list the numerous individuals, universities, and museums that were recipients of his collections. 相似文献