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61.
ABSTRACT: BACKGROUND: Diagnosis of amoebic liver abscess (ALA) in patients on anti-amoebic drugs is difficult. There is scanty data on this issue using Entamoeba histolytica (E. histolytica) lectin antigen and polymerase chain reaction (PCR). We studied lectin antigen, PCR, and IgG antibody in liver abscess patients. Liver aspirate of 200 patients, of which 170 had anti-amoebic drug prior to drainage, was tested for E. histolytica lectin antigen by ELISA, PCR, bacterial culture, and serum IgG antibody by ELISA. Classification of abscesses was based on result of anti-amoebic IgG antibody and bacterial culture, E. histolytica PCR and bacterial culture, and E. histolytica lectin antigen and bacterial culture was evaluated. FINDINGS: Using anti-amoebic IgG antibody and bacterial culture, 136/200 (68.0%) were classified as ALA, 12/200 (6.0%) as pyogenic liver abscess (PLA), 29/200 (14.5%) as mixed infection, and 23/200 (11.5%) remained unclassified. Using amoebic PCR and bacterial culture 151/200 (75.5%) were classified as ALA, 25/200 (12.5%) as PLA, 16/200 (8.0%) as mixed infection, and 8/200 (4.0%) remained unclassified. With E. histolytica lectin antigen and bacterial culture, 22/200 (11.0%) patients were classified as ALA, 39/200 (19.5%) as PLA, 2/200 (1.0%) as mixed infection, and 137/200 (68.5%) remained unclassified. CONCLUSIONS: E. histolytica lectin antigen was not suitable for classification of patients who had prior anti-amoebic treatment. However, PCR may be used as alternative test to anti-amoebic antibody in diagnosis of ALA.  相似文献   
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To compare the production and economic performance of two polyculture systems with different species combinations in brackishwater tide‐fed ponds, a 180‐day trial was carried out. In the first combination (T1), mullets (Mugil cephalus, Liza tade and L. parsia at 3 : 1 : 1.3 ratio) and tiger shrimp (Penaeus monodon) and in the second (T2), milkfish (Chanos chanos) and tiger shrimp were stocked keeping the fishes and shrimp at 8000 and 20 000 numbers ha?1, respectively, in both treatments with duplicate ponds. Since shrimp was an important component of these two systems with open water exchange, the dynamics of heterotrophic bacteria (THB) including Vibrio spp. (TVC) and the occurrence of viral infection agents were studied to understand the disease risks. Among the fishes in T1, M. cephalus attained the highest final weight of 92.29 ± 4.36 g followed by L. tade and L. parsia with 80.40 ± 4.02 and 54.02 ± 2.11 g, respectively. C. chanos in T2 had the highest net weight gain (127.85 g) and daily weight gain (0.71 g day?1), while M. cephalus in T1 attained the highest specific growth rate (1.60% day?1). Growth parameters of tiger shrimp were almost similar in both treatments, with no significant differences (P > 0.05). Though total production of fishes and shrimp was lower in T1 (689 kg ha?1 180 day?1), it was not significantly different (P > 0.05) from T2 (721 kg ha?1 180 day?1). Monthly THB and TVC were not alarming and the absence of viral infections in shrimp indicated no disease risk. Total income from T1 was significantly higher (P < 0.05) than that of T2, but net income and benefit‐cost ratio were insignificantly different between the treatments (P > 0.05). The present findings indicate that upon availability of stocking materials, both polyculture systems would be suitable farming options.  相似文献   
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The osmoregulatory isoform of dihydroxyacetone phosphate (DHAP) reductase (Osm-DHAPR) is an enzyme unique to Dunaliella, photosynthetic unicellular green algae adapted to extreme environments. This is the first report of purification of an isoform of DHAP reductase from Dunaliella, specifically the osmoregulatory isoform that is involved in the synthesis of free glycerol for osmoregulation in extreme environments, such as high salinity. The Osm-DHAPR is cold labile, inactivated by ammonium sulfate, forms a strong complex with Rubisco, and is unstable in the absence of glycerol. These difficulties have been addressed, and a four-step procedure has been developed to purify the Osm-DHAPR from Dunaliella tertiolecta: precipitation of Rubisco by polyethylene glycol, followed by successive chromatography on DEAE cellulose, Sephacryl S-200, and Red Agarose. Yield of the purified enzyme was 3.6%, with a specific activity of 938 micromol.min-1.mg-1 of protein and a subunit molecular mass of approximately 38 kDa. A maximum specific activity of 2580 micromol.min-1.mg-1 of protein could be achieved by assay with 150 mM NaCl. The Osm-DHAPR had little preference for NADH or NADPH, but it is highly specific for DHAP. Other metabolites of glycolysis, the tricarboxylic acid cycle, and the C3 reductive photosynthetic carbon cycle were not reduced by the enzyme. The purified enzyme was stimulated three-fold by 150 to 250 mM NaCl/KCl and by 25 mM MgCl2. Detergents, lipids, or long-chain acyl CoA derivatives, all of which inhibited the chloroplastic glyceride form of DHAP reductase, did not affect the activity of Osm-DHAPR. The Osm-DHAPR has different properties than the other chloroplastic isoform of DHAP reductase from plants and algae for glycerol phosphate formation and triglyceride synthesis.  相似文献   
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Background  

Specification of primordial germ cells in mice depends on instructive signalling events, which act first to confer germ cell competence on epiblast cells, and second, to impose a germ cell fate upon competent precursors. fragilis, an interferon-inducible gene coding for a transmembrane protein, is the first gene to be implicated in the acquisition of germ cell competence.  相似文献   
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Nuclear image morphometry and cytologic grade of breast carcinoma   总被引:2,自引:0,他引:2  
OBJECTIVE: To correlate visual cytologic grade with automated nuclear morphometry of carcinoma of the breast. STUDY DESIGN: We randomly selected 24 histologically proven infiltrating ductal carcinomas of the breast and 10 benign breast lesions (fibroadenoma). Hematoxylin-eosin-stained fine needle aspiration cytology (FNAC) smears were selected for both cytologic grade and automated image morphometry. The same hematoxylin-eosin-stained FNAC smears were studied for area, convex area, standard deviation of nuclear area, diameter, perimeter and convex perimeters of nucleus. At least 100 cells from each case were measured with an image cytometer. RESULTS: Mean nuclear area, standard deviation of nuclear area, nuclear diameter, convex area, convex perimeter and perimeter were significantly increased from benign versus grade 1 carcinomas and grade 1 versus grade 2 and 3 carcinomas (one way ANOVA test). However, there was no significant difference in grade 2 versus grade 3 carcinomas. CONCLUSION: Automated image cytometry rapidly and successfully measures various nuclear parameters. The measurement of various nuclear parameters would be helpful in future applications of automated diagnosis and grading of breast carcinomas from cytologic material.  相似文献   
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