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91.
Ralf Thiel Philip Riel Renate Neumann Helmut M. Winkler Uwe Böttcher Tomas Gröhsler 《Hydrobiologia》2008,602(1):161-177
The status of twaite shad was investigated within the Southern Baltic Sea (ICES subdivision 22–27) and transitional area between
the Baltic and North Seas (division IIIa). The following sources of data were analysed: (i) commercial catch statistics and
relevant publications, (ii) records from ichthyological museum collections, (iii) records from recent commercial and recreational
fisheries, (iv) research fisheries with trawls. A total of 476 records of twaite shad including more than 16 million individuals
were obtained for the time between the years 1836 and 2005. About 72.9% of all records originated from commercial catch statistics
and publications, whereas 18.9% were received from ichthyological collections. Research fisheries provided 6.3%, and 1.9%
of the records were obtained from recent commercial and recreational fisheries. Most records of twaite shad were estimated
for subdivisions 24 (45.2%) and 26 (35.5%). From 1836 to 1959, 29.6% of the records date from the period until 1899. 70.4%
of the records of twaite shad originate from the twentieth century until 1959. The mean annual catch of twaite shad between
1891 and 1959 amounted to 86,674 kg within subdivisions 24–26 of the Southern Baltic Sea. Catch data show an approximately
20-year-cyclicity of maximum yields and minimum catches, respectively. The maximum annual yield of twaite shad in subdivisions
24–26 (474,700 kg) was registered in 1940, the minimum annual yield was estimated in 1958 (10 kg). In the 1950s, the annual
catches of twaite shad declined sharply. Until 1960 twaite shad catches and records originated mainly from the Pommeranian
Bay/Pommeranian Coast and adjacent waters including the Szczecin Lagoon (subdivision 24), the Bay of Gdańsk, Vistula Lagoon
and Vistula Spit (subdivision 26) and from the Curonian Lagoon and Curonian Spit (subdivision 26). The highest catches of
twaite shad originated from the area of Curonian Lagoon/Curonian Spit from 1941 to 1960. Seasonal catches of twaite shad showed
maximum values from May to July. From 1960 to 1989, only four records of A. fallax were registered in the Southern Baltic Sea which originated from German coastal waters in subdivisions 22 and 24. A total
of 107 records of twaite shad was obtained in subdivisions 20–27 from 1990 to 2005. Most of these recent records originate
from a twaite-shad stock in subdivisions 24, 25 and 26. There are indications which suggest a separate stock of twaite shad
in subdivisions 20 and 21. Disappearance and recovery of twaite shad stocks were probably caused by the following factors:
construction of barriers in rivers with spawning sites of twaite shad; habitat destruction in those rivers as consequence
of gravel extraction and reengineering scheme to improve navigation and for flood defence purposes, water pollution in the
lagoons of the Southern Baltic and in their tributaries, commercial fishery in the Southern Baltic and climatic variation
in the Baltic Sea basin south of the latitude of 60° N.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Guest editors: S. Dufour, E. Prévost, E. Rochard & P. Williot
Fish and diadromy in Europe (ecology, management, conservation) 相似文献
92.
93.
Jose M. Pujolar 《Molecular ecology》2013,22(7):1761-1762
Eels are unique species in the biological world. The two North Atlantic eel species, the American eel (Anguilla rostrata) and the European eel (A. anguilla), occupy a broad range of habitats from the Caribbean to Greenland in the western Atlantic and from Morocco to Iceland in the eastern Atlantic, respectively. North Atlantic eels have a catadromous life cycle, spawning only in the Sargasso Sea and spending the majority of their lives in continental (fresh, brackish and coastal) waters. Despite such a wide distribution range, North Atlantic eels have been regarded as a textbook example of panmictic species. In contrast with the large amount of population genetic studies testing the panmixia hypothesis in the European eel, a relatively modest effort has been given to study the population structure of the American eel. In this issue of Molecular Ecology, Côté et al. ( 2013 ) present the most comprehensive American eel data set to date, which includes samples of different life stages obtained throughout all its distribution range in North America. Results show a total lack of genetic differentiation among samples and provide decisive evidence for panmixia in the American eel. 相似文献
94.
95.
Paul G. Jensen Charlotte L. Demers Stacy A. Mcnulty Walter J. Jakubas Murray M. Humphries 《The Journal of wildlife management》2012,76(3):489-502
Many forest tree species produce seed (mast) crops that are consumed by a variety of wildlife species and these pulsed resources may mediate interactions among predator and prey populations. In the northern hardwood forests of New York, we investigated interactions among mast production, prey abundance, and harvests of American martens (Martes americana) and fishers (Martes pennanti) during 1988–2009. Mast production for beech (Fagus grandifolia), sugar maple (Acer saccharum), and mountain ash (Sorbus americana) was synchronous and an alternate-year pattern in production was evident for most of the time series. We documented considerable temporal variation in summer small mammal relative abundance and our numerical response models received substantial support for 5 of the 8 species, indicating lagged responses to autumn mast crops. Trap response of martens to the autumn production of beech mast and mountain ash berries was immediate and numerical responses to the relative abundance of small mammal prey occurred during the preceding summer. The age structure of the marten harvest differed based on the dominant alternate-year pattern of summer prey relative abundance and autumn mast production (χ24 = 33.06, P < 0.001). The proportion of juvenile marten in the autumn harvest was 52% and 34% following summers when small mammal relative abundance was high and low, respectively and these differences resulted in a persistent cohort effect that was apparent until age 3.5. Trap response of fishers to the autumn production of beech mast was immediate and numerical responses to the relative abundance of Sciurid prey occurred during the preceding summer. Marten and fisher harvests fluctuated similarly among New York, Maine, and New Brunswick, which may indicate regional synchronization of mast crops and responses of martens and fishers to similar prey dynamics. A better understanding of how food availability influences demographic responses and trapping vulnerability of martens and fishers would aid our ability to manage harvests of these species on a sustained yield basis. © 2011 The Wildlife Society. 相似文献
96.
Ortner DJ Butler W Cafarella J Milligan L 《American journal of physical anthropology》2001,114(4):343-351
The authors surveyed subadult human skeletons from Native American archeological sites in the United States for evidence of skeletal lesions associated with scurvy. Geographic regions surveyed include the Midatlantic area, the Southeast (Florida), the Southwest, and the Plains. The prevalence of probable subadult scurvy ranged from zero in the Plains samples to 38% in a small sample from Florida. These data indicate the likelihood that scurvy was a significant childhood disease in many Native American groups. Reasons for variation in prevalence remain speculative but include regional and seasonal variation in food types and abundance, cultural patterns of storage and utilization, periodic food shortages, and the relative importance of corn in the diet. These factors are part of a nutritional complex that is related to disease prevalence which can be studied through evidence seen in archeological human remains. 相似文献
97.
A comparison of testing methods for constituents of Ginkgo biloba was performed as part of the process for determining which of the many available analytical methods was most appropriate for inclusion in the American Herbal Pharmacopoeia (AHP). Three primary methods were reviewed: those adopted by the European Pharmacopoeia, the National Science Foundation-Institute for Nutraceutical Advancement (NSF-INA) and the United States Pharmacopeia. Methods were compared by evaluating sample preparation and hydrolysis, precision and methods of total flavonol glycoside calculation by two independent laboratories. The AHP adopted the method of NSF-INA for inclusion in the AHP monograph owing to observed superiority of this method in terms of precision, glycoside calculation, ease of sample preparation and chromatographic parameters. 相似文献
98.
Adam R. Shapiro 《Journal of the history of biology》2008,41(3):409-433
In discussing the origins of the antievolution movement in American high schools within the framework of science and religion,
much is overlooked about the influence of educational trends in shaping this phenomenon. This was especially true in the years
before the 1925 Scopes trial, the beginnings of the school antievolution movement. There was no sudden realization in the
1920’s – sixty years after the Origin of Species was published – that Darwinism conflicted with the Bible, but until evolution was being taught in the high schools, there
was no impetus to outlaw it. The creation of “civic biology” curricula in the late 1910’s and early 20’s, spearheaded by a
close-knit community of textbook authors, brought evolution into the high school classroom as part of a complete reshaping
of “biology” as a school subject. It also incorporated progressive ideologies about the purposes of compulsory public education
in shaping society, and civic biology was fundamentally focused on the applications of the life sciences to human life. Antievolution
legislation was part of a broader response to the ideologies of the new biology field, and was a reaction not only to the
content of the new subject, but to the increasingly centralized control and regulation of education. Viewing the early school
antievolution movement through the science-religion conflict is an artifact of the Scopes trial’s re-creation of its origins.
What largely caused support for␣the school antievolution movement in the South and particularly Tennessee were concerns over
public education, which biology came to epitomize. 相似文献
99.
Kołodziej Barbara Kochan Ewa Kazimierczak Jerzy Chmiel Aleksander 《Plant Growth Regulation》2006,48(1):13-19
American ginseng (Panax quinquefolium L.) is a perennial medicinal herb originally grown in Canada and USA, and recently also in China, Australia, Holland and
Poland. Several commercial preparations are produced from ginseng roots, that are known for their antifatigue, antitumor,
antistress and immune system stimulating functions. The medicinal properties are due mainly to the active components – ginsenosides.
In this work, the results of field cultivation experiments are presented that examine the effects of foliar application of
several growth regulators on quality parameters and ginsenoside content of P. quinuefolium roots. The growth regulators tested, i.e., kinetin, daminozide, mixture of gibberellic acid (GA3) with potassium salt of α-naphthalene acetic acid (kNAA) and new preparation – IPO-1 – benzimidazole derivative (obtained
from the Institute of Organic Industry in Warsaw – at present during the process of patent), were applied at a concentration
of 100 or 200 mg l−1 in the middle of June in the 2nd year of vegetation. After 4 years of cultivation, the roots were dug up and dried, and subsequently
the quantitative analysis of individual saponins (Rb1, Rb2, Rc, Rd, Re, Rg1) by HPLC was performed. Growth regulators significantly affected quality parameters, morphological features and accumulation
of individual and total ginsenosides in ginseng roots. Regardless of doses, the plant roots treated with growth regulators
had a higher content of total ginsenosides in comparison to the control. The growth regulators also affected individual ginsenosides
level and narrowed the ratio of Rb:Rg group. The application of kinetin, daminozide and benzimidazole derivative for foliar spray during 2nd year of American ginseng
vegetation caused a significant increase in air dry weight of roots and aboveground parts whereas the mixture of GA3 and kNAA showed a decreasing effect. An increase of roots size was observed using higher doses (200 mg l−1) of kinetin and daminozide while a decreasing tendency appeared with the application of the other preparations. 相似文献
100.
《Palaeoworld》2023,32(3):547-554
Mesotheres (Notoungulata: Typotheria) are among the most common mammals found in upper Miocene to Pliocene deposits of central Argentina, including the classic type Monte Hermoso locality, which defines the Montehermosan South American Land Mammal “Age”. Nevertheless, the correct name for the mesothere species from this site has been shrouded in uncertainty for well over a century due to questions of taxonomic priority, specimen provenance, and ontogenetic changes in dental formula. Since the mesotheres from Monte Hermoso were named, three distinct species have been formally considered as the type species of the genus: (1) Pseudotypotherium bravardi; (2) “Pseudotypotherium” maendrum; and (3) Pseudotypotherium exiguum. However, none of these species is a nominal species of the Pseudotypotherium genus; all three were originally referred to Typotherium. Article 67.2 of the International Code of Zoological Nomenclature (ICZN, 1999) indicates that only species considered as nominal species are eligible to set the type; in the case of Pseudotypotherium, these include: P. pulchrum, P. carlesi, P. hystatum, and P. carhuense. We conclude that Pseudotypotherium pulchrum F. Ameghino, 1904 (holotype MACN A 10299, Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, Ameghino Collection), is the type species of the mesotheriid notoungulate genus from Monte Hermoso. According to Article 68.2, F. Ameghino fixed the type by original designation in 1904 when he described P. pulchrum and included “n. g., n. sp.”. Two of the other species previously considered species P. (= T.) bravardi and P. (= T.) exiguum are invalid as type species according to Article 70.2, since their designations overlooked the previous type fixation. The third species (M. (= T.) maendrum) represents a different mesothere genus (Mesotherium) that only occurs in younger (Pleistocene) deposits. Our analysis puts an end to a historical debate that has been ongoing for more than a century regarding the identity of this well-represented late Miocene–Pliocene mesotheriine genus (Pseudotypotherium). This study provides a solid taxonomic foundation for future studies on intraspecific and ontogenetic variation of Pseudotypotherium pulchrum. 相似文献