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871.
D L da Mota L L George P P Pinheiro N L Pinheiro 《Gegenbaurs morphologisches Jahrbuch》1989,135(2):367-377
The intestinal of the 3-toed sloth, Bradypus tridactylus, was studied macroscopically, with light microscope and with histochemical methods for mucosubstances. Macroscopically, the inner surface of the duodenum shows longitudinal and circular folds. There is no caecum, nor appendix. The large intestine consists of a short colon and a large rectal pouch, which has a thick wall. The mucosa of the small intestine has long leaf-shaped villi covered with columnar epithelium having a well developed striated border, and the goblet cells are scattered among the columnar cells. An association between neutral and acidic mucosubstances was detected in the goblet cells. The duodenal (Brunner's) glands are confined exclusively in the lamina propria of the duodenum. No Paneth cells were observed in the crypt lining. Argyrophil and argentaffin cells were found in the entire length of the intestine. The large intestine does not possess villi, but many goblet cells were observed in its mucosa. 相似文献
872.
Mahdieh Ahmadi Ahmad Noori Bita Kalvani Neitali Marcelo Antonio Amaro Pinheiro 《Acta zoologica》2023,104(2):176-184
The purpose of this study was to investigate the relative growth and sexual dimorphism in the hermit crab Clibanarius signatus. The evaluation was done with 955 specimens (494 males, 251 females, and 210 intersexes) captured in Persian Gulf (Iran) during January to December 2015. Animals were submitted to measurements related to weight (BW, total wet weight) and body size related to cephalic shield (SW, width; and SL, length) and propodus of both chelipeds (CPL, length; and CPW, width). Males were larger and heavier than females and intersexes. Both males and females showed a negative allometric growth for the SL–BW and SL–SW relationships, but a positive allometric growth to intersex specimens. To SL–CPL relationship, a negative allometric growth was confirmed in males and females independent of the laterality of the CPL, whereas a contrast was verified in intersexes, with a positive allometric growth occurred for both hands. To SL–CPW relationship, a negative allometric growth (b < 1) occurred in females, independent of the laterality of the CPW, while in males, a positive allometric pattern was confirmed. In intersexes, this relationship was positive except for the right CPW which was isometric. Sexual dimorphism was evident in Clibanarius signatus, with males being the largest and females the smallest specimens in the population. 相似文献
873.
Water deficit (WD) in Lupinus albus L. brings about tissue-specific responses that are dependent on stress intensity. Carbohydrate metabolism is very sensitive to changes in plant water status. Six days from withholding water (DAW), sucrose, glucose and fructose levels of the leaf blade had already increased over 5-fold, and the activities of SS and INV(A) had increased c. 1.5-2 times. From 9 DAW on, when stress intensity was more pronounced, these effects were reversed with fructose and glucose concentrations as well as INV(A) activity dropping in parallel. The stem (specifically the stele) responded to the stress intensification with striking increases in the concentration of sugars, N and S, and in the induction of thaumatin-like-protein and an increase in chitinase and peroxidase. At 13 DAW, the plants lost most of the leaves but on rewatering they fully recovered. Thus, the observed changes appear to contribute to a general mechanism of survival under drought, the stem playing a key role in that process. 相似文献
874.
Marcelle D. Alves Lia Pinheiro Denise Manica Laura M. Fogliatto Christina Fraga Luciano Z. Goldani 《Mycopathologia》2011,171(1):57-59
Histoplasma capsulatum has not typically been associated with sinusitis in either immunocompetent or immunocompromised hosts. We report a case of
sinusitis caused by H. capsulatum in a patient with chronic lymphocytic leukemia and discuss the reported cases of this rare clinical manifestation of histoplasmosis
in the medical literature. 相似文献
875.
Campesterol Semi-Synthetic Derivatives as Potential Antibacterial: in vitro and in silico Evaluation
Francisco Erivaldo Freitas da Silva Francisco das Chagas Lima Pinto Otília Deusdênia Loiola Pessoa Aluísio Marques da Fonseca José Galberto Martins da Costa Gilvandete Maria Pinheiro Santiago 《化学与生物多样性》2023,20(7):e202300536
In this study, twelve campesterol derivatives ( 2 – 13 ) were prepared by esterification reaction at the hydroxy group in C-3 and catalytic hydrogenation at the carbon-carbon double bond in C-5(6). All obtained compounds were characterized by IR, 1H-NMR, 13C-NMR, and MS spectra. Campesterol ( 1 ) and its derivatives ( 2 – 13 ) were evaluated in vitro against Staphylococcus aureus (ATCC 6538), Streptococcus mutans (ATCC 0046), Escherichia coli (ATCC 10536), Pseudomonas aeruginosa (ATCC 15442), and Klebsiella pneumoniae (ATCC 10031) using the microdilution method. Among tested compounds, 4 , 6 , 9 , 11 , 12 , and 13 displayed the best antibacterial activity. Moreover, to support the antibacterial activity experiments, the investigation of molecular interactions of more active compounds, and also compound 1 and neomycin, used as starting material and positive control, respectively, at the binding site of the target proteins was performed using molecular docking simulations. Four compounds ( 7 , 9 , 10 and 11 ) are herein described for the first time. 相似文献
876.
877.
Microsatellite Polymorphisms in Cassava Landraces from the Cerrado Biome, Mato Grosso do Sul, Brazil
M. V. B. M. Siqueira T. T. Pinheiro A. Borges T. L. Valle M. Zatarim E. A. Veasey 《Biochemical genetics》2010,48(9-10):879-895
Using nine microsatellite loci, we investigated genetic structure and diversity in 83 Brazilian cassava accessions, including several landraces, in the Cerrado biome in Mato Grosso do Sul, Brazil. All nine loci were polymorphic, averaging 6.00 alleles per locus. Treating each of seven municipalities as a cassava group or population, they averaged 3.5 alleles per locus, with 97% polymorphic loci, high values for observed heterozygosity (0.32) and gene diversity (0.56). Total genetic variability was high (0.668), and most of this genetic variability was concentrated within municipalities (0.577). Cluster and structure analyses divided accessions into two major clusters or populations (K = 2). Also, a significant genetic versus geographic correlation was found (r = 0.4567; P < 0.0260). Migratory routes in the Cerrado are considered main contributors to the region’s high cassava diversity and spatial genetic structure, amplifying interactions between traditional farmers and the evolutionary dynamics of this crop. 相似文献
878.
N. Llanes P. Fernandes R. Lon J. M. S. Cabral H. M. Pinheiro 《Journal of Molecular Catalysis .B, Enzymatic》2001,11(4-6):523-530
Mycobacterium sp. NRRL B-3805 cells immobilized on Celite were effectively used for the selective side-chain cleavage of sitosterol to androstenedione (AD) in organic media (phthalate derivatives). Kinetic studies were performed with sitosterol concentrations up to 24 mM, with different Celite materials and particle sizes. Higher activity levels were observed when a larger pore size Celite was used as immobilization matrix. Substrate inhibition was observed for sitosterol concentrations above 6 mM. Toxicity effects were not apparently correlated with the high log P solvents (>9) here used as bioconversion media. The use of immobilized cells in repeated batch biotransformations did not prove effective, mainly due to biocatalyst desorption during the periodical, aqueous washing steps used for nutrient delivery to the cells. 相似文献
879.
The abundance and ecological distribution of the shrimp Pleoticus muelleri as a function of certain environmental factors were investigated from January 1998 through December 1999 in the region of Ubatuba, São Paulo, Brazil. The collections were made monthly in the bays of Ubatumirim (UBM), Ubatuba (UBA) and Mar Virado (MV). Each bay was divided into six sampling transects, four transects parallel to the shoreline and two near the rocky shores on the opposite side. We employed a commercial shrimp boat equipped with two double-rig nets. A total of 6252 shrimp were collected, including 3321 from MV, 1467 from UBM, and 1464 from UBA. Most of the shrimp were caught in the deeper, higher-salinity areas. The high abundance of P. muelleri observed in the southern part of the region studied was related to a sediments with a higher percentage of silt and clay. The numbers of P. muelleri were positively correlated with periods of cooler temperatures. Thus, temperature and the type of sediment were determinant factors in the distribution of P. muelleri in this region. 相似文献
880.
The Babassu palm is a very important forest resource for over 300 000 families in Maranhao State, Northeastern Brazil. The rudimentary nature of the babassu kernel extraction process employed by the peasantry has been blamed for being one of the key factors of the crisis in the babassu oil industry economy. This paper provides the results of the use of a new model for sustainable exploitation of babassu palm forests and integral fruit processing at the village and farm- level. The new model includes the coordination of fruit collection and storage, and the gradual replacement of the traditional system of manual breaking by mechanized integral processing at local level. The machinery consists of a dehusking machine (to separate epicarp and mesocarp), a breaking machine (to crack the dehusked fruits), and a machine to separate the small pieces of broken endocarpfrom the kernels. The preliminary results arising from the application of the new model are shown and discussed. 相似文献