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361.
Plasmonics - Raman spectroscopy (RS) is a modern scientific analytic fingerprint technique that detects, examines, and analyzes the constituent chemical composition of various substances...  相似文献   
362.
363.
Notch receptor regulates differentiation of almost all tissues and organs during animal development. Many mechanisms function at the protein level to finely regulate Notch activity. Here we provide evidence for Notch regulation at an earlier step - mRNA 3′ processing. Processing at the Notch consensus polyadenylation site appears by default to be suppressed in Drosophila embryos. Interference with this suppression, by a mutation, results in increased levels of polyadenylated Notch mRNA, excess Notch signaling, and severe developmental defects. We propose that Notch mRNA 3′ processing is negatively regulated to limit the production of Notch protein and render it a controlling factor in the generation of Notch signaling.  相似文献   
364.
Serum free testosterone (fT) concentrations are often calculated, however different equations often yield discrepant results. This study explores the sources of this variability. We compared three established and two new equations that differed only by their testosterone association constants with isotope dilution equilibrium dialysis in two patient groups with different gender distributions. Equation components were examined to determine how they impacted correlation with isotope dilution equilibrium dialysis. Association constants derived for each patient group correlated best with isotope dilution equilibrium dialysis for that group and not the other set. Samples with the poorest correlation between isotope dilution equilibrium dialysis and calculated fT results had significantly higher SHBG concentrations. Regardless of equation, ≥25% of samples showed unacceptable deviation from isotope dilution equilibrium dialysis. Association constants and gender makeup and SHBG concentration of the patient groups used to establish an equation all significantly impact correlation with isotope dilution equilibrium dialysis. Application of many fT equations to wider populations will therefore frequently yield results that differ substantially from isotope dilution equilibrium dialysis.  相似文献   
365.
Mastitis is a serious problem in dairy sector and among various aetiological agents, the incidence of staphylococci and streptococci remains high in milking animal. The present study was focused on detection of staphylococci and streptococci in winter season. Milk samples (117) of mastitic animals were tested for presence of staphylococci and streptococci using biochemical and PCR based assays. The testing revealed majority of animals (90.6%) were infected with more than one causative agent. Amongst 117 sample, 109 and 90 comprised of staphylococci and 90 streptococci, respectively. Distribution proportion of S. aureus, S. epidermidis, S. agalactiae, S. uberis and S. dysgalactiae among the mastitic cases was found as 64.9, 7.7, 5.1, 1.7, 48.7, 65.8 and 0.8%, respectively. Streptococci and staphylococci were observed in different combinations and the frequent were S. aureus/S. agalactiae/S. uberis, S. aureus/S. uberis, S. aureus/S. agalactiae and S. agalactiae/S. uberis which were accounted for 23.9, 19.7, 5.9 and 2.6%, respectively. Approximately half of the (52.1%) cases were observed for reoccurrence of mastitis. Reoccurrence of mastitis in winter season among these cases was significantly low as compared to summer (cattle-5 cases; buffaloes-2 cases). In addition, prevalence of S. aureus, S. agalactiae, S. uberis, and S. epidermidis in reoccurring mastitic cases was 73.7, 63.9, 45.9 and 6.6%, respectively. The observations revealed mastitis causing pathogens remains in hidden phase in winter season; however, cannot be neglected. The observation might be helpful in culling or segregation of cows for mastitis reduction programmes.  相似文献   
366.
Kumari  Archana  Goyal  Meenakshi  Kumar  Ravinder  Sohu  R. S. 《Protoplasma》2021,258(1):87-102

Shoot fly [Atherigona soccata (Rondani)] is a destructive pest of sorghum at the seedling stage and causes huge losses to grain yield and green fodder. The host-plant resistance mechanism is the best approach to reduce the attack of insects in plants. The damage parameters, morphophysiological traits, and biochemical metabolites had been investigated in the leaves and stem of contrasting sorghum genotypes, viz., resistant (IS18551, ICSV705, ICSV700), moderately resistant (PSC-4), and susceptible (SWARNA and SL-44) at 15 and 21 days after emergence (DAE) against shoot fly infestation. The resistant genotypes recorded lowest shoot fly oviposition and incidence (0.3–0.7 eggs plant−1 and 10–15%) than the susceptible genotypes (2.4–3.0 eggs plant−1 and 70–80%), respectively. The susceptible genotype SWARNA recorded 50% and 80% higher deadheart formation than the resistant genotype IS18551 at 15 and 21 DAE, respectively. Resistant genotypes exhibited higher trichome density at adaxial and abaxial part of leaf (118–145 and 106–131) with pink colored leaf sheath (scale 1.50–3.25), glossy leaves (scale1.00–1.25), and lower leaf surface wetness (scale1.25–2.00) compared with susceptible genotype with 49.3–73.3 and 25.3–64.0, scale 2.50–4.00, scale 2.75–3.50, and scale 3.25–4.25 for the respective parameters. Another defense response of sorghum toward the insect attack was modulation of plant metabolism. The infested genotypes responded to insect attack by upregulation of total soluble sugar, total phenol, prussic acid, and chlorophyll content by 1.2–2.1-fold, 1.5–2.0-fold, 1.2–1.3-fold, and 1.2–3.9-fold with more induction in susceptible genotypes at 21 DAE. On the whole, the present study indicates that morphophysiological and biochemical attributes contribute toward the resistance mechanism in sorghum against shoot fly infestation.

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367.
Clostridium lentocellum SG6 fermented various pure crystalline cellulosic materials efficiently with maximum acetic acid yield (gram acetic acid/gram substrate) of 0.67, at low substrate (8 g l−1) concentration. The strain grew poorly on crude biopolymers but fermented them easily after alkali treatment, when grown with 8 g substrate l−1 concentration of alkali-extracted cotton straw (AECS), paddy straw (AEPS) and sorghum stover (AESS) etc. The acetic acid to substrate (A/S) ratios were similar to those obtained with pure cellulosic materials. An increase in substrate concentration led to a decreased A/S ratio and a decreased percentage of substrate degraded. At high substrate concentration of 75 g filter paper l−1, the strain SG6 converted 63.2 g filter paper into 31.28 g acetic acid l−1. At 100 g l−1 concentrations, AECS and AEPS served as the best substrates for acetic acid production when compared with other biopolymers. A maximum amount of 30.98 and 30.86 g acetic acid was produced from 70.6 g AEPS and 70.1 g AESS l−1 of medium by strain SG6, respectively. Acetic acid production of 0.67 g g−1 pure cellulose (Whatman No. 1 filter paper), 0.63 g g−1 of alkali-treated cotton straw (AECS) are the highest among the cellulolytic bacteria reported so far in mono culture fermentations with pure and native cellulosic materials. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
368.
Molecular Biology Reports - Common bean is gaining acceptance as one of the most valuable major food consumed worldwide owing to innumerable nutritional and therapeutic benefits. Comparatively less...  相似文献   
369.
The use of transgenic plants in the production of recombinant proteins for human therapy, including subunit vaccines, is being investigated to evaluate the efficacy and safety of these emerging biopharmaceutical products. We have previously shown that synthesis of recombinant glycoprotein B (gB) of human cytomegalovirus can be targeted to seeds of transgenic tobacco when directed by the rice glutelin 3 promoter, with gB retaining critical features of immunological reactivity (E.S. Tackaberry et al. 1999. Vaccine, 17: 3020-3029). Here, we report development of second generation transgenic plant lines (T1) homozygous for the transgene. Twenty progeny plants from two lines (A23T(1)-2 and A24T(1)-3) were grown underground in an environmentally contained mine shaft. Based on yields of gB in their seeds, the A23T(1)-2 line was then selected for scale-up in the same facility. Analyses of mature seeds by ELISA showedthat gB specific activity in A23T(1)-2 seeds was over 30-fold greater than the best T0 plants from the same transformation series, representing 1.07% total seed protein. These data demonstrate stable inheritance, an absence of transgene inactivation, and enhanced levels of gB expression in a homozygous second generation plant line. They also provide evidence for the suitability of using this environmentally secure facility to grow transgenic plants producing therapeutic biopharmaceuticals.  相似文献   
370.
Staphylococcus aureus is recognized as a major etiological agent of the most important udder disease; mastitis. The virulence potential of S. aureus isolates is attributed to a combination of extracellular factors and invasive properties that are controlled at the genomic level. In this study molecular variations were studied among the 128 S. aureus isolates obtained from the mastitic crossbred cattle. The polymorphic patterns of protein A, coagulase, and IG genes were studied in the isolates using the PCR and PCR–RFLP methods. In addition, presence of other virulence genes responsible for the expression of adhesins and toxins was also screened. A considerable genetic variation was observed in amplified fragment of SPA, IG and CLF genes. The PCR–RFLP of COA gene yielded five different patterns. Occurrence of EBP, ENO and FNBA was found to be common in both high and low virulence isolates. However, the prevalence of FNBB and toxin genes was higher in clinical than subclinical isolates. The distribution proportions of adhesin genes EBP, FIB, FNBB, CNA, BBP, MAP CAP5, and CAP8 were 60.2, 59.4, 21.9, 6.3, 5.5, 80.5, 56.3, and 22.7%; for AGR I, II, III, and IV were 44.5, 32.8, 12.5, and 10.2%; and for toxins genes HLB, SEB, SEC, SED, SEE, SEG, and SEI were 82.0, 3.1, 5.5, 3.9, 0.8, 16.4, and 55.5%, respectively. The proportions of FNBB, EBP, FIB, HLB, BBP, SEG, and SEI genes were observed more in clinical cases. The significant genetic variations in SPA, COA, IG, and CLF genes were useful to differentiate the isolates that might be valuable for mastitis reduction programme.  相似文献   
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