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151.
Mucus hypersecretion is a critical component of cystic fibrosis (CF) pathogenesis. The effects of dysfunction of the cystic fibrosis transmembrane regulator (CFTR) on mucin expression were examined using the tracheo-bronchial mucin (TBM) gene as an indicator. TBM mRNA expression was assessed in a human bronchial epithelial cell line (HBE1) and human nasal mucosal explants in vitro. Antisense phosphorothioate oligodeoxynucleotides (S-ODN) to TBM suppressed baseline expression of TBM mRNA in both systems, but had no effect on glyceraldehyde phosphate dehydrogenase mRNA (GAPDH) expression. Sense and missense (multiple scrambled control oligonucleotides) S-ODNs had no effect. 8Br-cAMP and PGE1 significantly elevated TBM mRNA expression. These increases were also specifically inhibited by the antisense S-ODNs. In order to induce a CF-like state, S-ODN to CFTR were added to explants. Antisense CFTR S-ODNs were anticipated to reduce the expression of cellular CFTR protein, and the level of CFTR function. Antisense, but not sense or missense, CFTR S-ODN significantly increased TBM mRNA expression. These data suggest that mucin hypersecretion in CF may be a direct consequence of CFTR dysfunction; the specific mechanism through which this effect is mediated is not known.  相似文献   
152.
153.
Echinococcosis is a multisystem disease and has propensity to involve any organ, an unusual anatomical site, and can mimic any disease process. Primary peritoneal echinococcosis is known to occur secondary to hepatic involvement but occasional cases of primary peritoneal hydatid disease including pelvic involvement have also been reported. We report here 1 such case of primary pelvic hydatidosis mimicking a malignant multicystic ovarian tumor where there was no evidence of involvement of the liver or spleen. Our patient, a 27-year-old female, was detected to have a large right cystic adnexal mass on per vaginal examination which was confirmed by ultrasonography. Her biochemical parameters were normal and CA-125 levels, though mildly raised, were below the cut off point. She underwent surgery and on exploratory laparotomy, another cystic mass was found attached to the mesentery of the small gut. The resected cysts were processed histopathologically. On cut sections both large cysts revealed numerous daughter cysts. Microscopic examination of fluid from the cysts revealed free scolices with hooklets and the cyst wall had a typical laminated membrane with inner germinal layer containing degenerated protoplasmic mass. The diagnosis of pelvic hydatid disease was confirmed and patient was managed accordingly. Hydatid disease must be considered while making the differential diagnosis of pelvic cystic masses, especially in endemic areas.  相似文献   
154.
The aim of present study was to determine the changes of sodium, potassium, chloride, copper, and zinc in serum of Nili-Ravi buffalo during pregnancy and lactation. The study was carried out on 25 Nili-Ravi buffaloes during March 2008 to February 2009 at Buffalo Research Institute, Pattoki, District Kasur. Blood samples were taken from each buffalo during early pregnancy (Phase EP), i.e., between 1 and 3 months gestation, mid pregnancy (Phase MP), i.e., between 4 and 6 months gestation, late pregnancy (Phase LP), i.e., between 7 and 10 months gestation, and during lactation (Phase LT). Serum sodium, potassium, and chloride were determined on a clinical chemistry analyzer whereas copper and zinc were determined on an atomic absorption spectrophotometer. The mean serum sodium, potassium, and chloride concentrations varied non-significantly (P > 0.05) during pregnancy and lactation. With advancing pregnancy, copper increased and was significantly high (P < 0.05) during late pregnancy whereas during lactation copper concentrations dropped significantly (P < 0.05). The zinc concentrations increased non-significantly during early and mid pregnancy. There were significant differences (P < 0.05) in zinc concentrations during lactation compared with late pregnancy. This study demonstrates that concentrations of serum sodium, potassium, and chloride remain unchanged during pregnancy and lactation whereas serum copper concentrations increased and zinc concentrations decreased with advancing pregnancy because of the demand of the fetus at different periods of pregnancy.  相似文献   
155.
The morphogenic potential and free-radical scavenging activity of the medicinal plant, Silybum marianum L. (milk thistle) were investigated. Callus development and shoot organogenesis were induced from leaf explants of wild-grown plants incubated on media supplemented with different plant growth regulators (PGRs). The highest frequency of callus induction was observed on explants incubated on Murashige and Skoog (MS) medium supplemented with 5.0 mg l−1 6-benzyladenine (BA) after 20 days of culture. Subsequent transfer of callogenic explants onto MS medium supplemented with 2.0 mg l−1 gibberellic acid (GA3) and 1.0 mg l−1 α-naphthaleneacetic acid (NAA) resulted in 25.5 ± 2.0 shoots per culture flask after 30 days following culture. Moreover, when shoots were transferred to an elongation medium, the longest shoots were observed on MS medium supplemented with 0.5 mg l−1 BA and 1.0 mg l−1 NAA, and these shoots were rooted on a PGR-free MS basal medium. Assay of antioxidant activity of in vitro and in vivo grown tissues revealed that significantly higher antioxidant activity was observed in callus than all other regenerated tissues and wild-grown plants.  相似文献   
156.
Samples of the cotton aphid, Aphis gossypii Glover, populations collected from the vicinity of Multan in central Pakistan from 1997 to 2000 were evaluated for pyrethroid resistance in comparison with a susceptible laboratory colony using a leaf-dip bioassay. Resistance to seven pyrethroid insecticides viz. cypermethrin, alphacypermethrin, zetacypermethrin, cyfluthrin, fenpropathrin, bifenthrin, and lambdacyhalothrin was generally very high. However, A. gossypii consistently showed lower resistance to deltamethrin than to other pyrethroids. The lower deltamethrin resistance implies that deltamethrin might be less affected by the resistance mechanism(s) present, a feature that could potentially be exploited in strategies for managing A. gossypii. The influence of insecticide use on cotton on the extent and dynamics of resistance in A. gossypii is discussed.  相似文献   
157.
Crocandine and isocrocandine, isolated from the seeds of C. candicans, have been shown by spectroscopy and chemical evidence to be macrocyclic diesters of turneforcidine and 3-hydroxy-2,3,4-trimethylglutaric acids.  相似文献   
158.
In this report, we describe the radiosynthesis of a new thiol-targeting prosthetic group for efficient radioactive iodine labeling of biomolecules. Radioiodination using the precursor 3 was performed to obtain 125I-labeled tetrazole 4b with high radiochemical yield (73%) and radiochemical purity. Using the radiolabeled 4b, a single free cysteine containing peptide and human serum albumin were labeled with 125I in modest-to-good radiochemical yields (65–99%) under mildly reactive conditions. A biodistribution study of [125I]7 in normal ICR mice exhibited lower thyroid uptake values than those of 125I-labeled human serum albumin prepared via a traditional radiolabeling method. Thus, [125I]7 could be employed as an effective radiotracer for molecular imaging and biodistribution studies. The results clearly demonstrate that 4b has the potential to be effectively implemented as a prosthetic group in the preparation of radiolabeled biomolecules.  相似文献   
159.
We report that a symmetric small-molecule ligand mediates the assembly of antibody light chain variable domains (VLs) into a correspondent symmetric ternary complex with novel interfaces. The L5* fluorogen activating protein is a VL domain that binds malachite green (MG) dye to activate intense fluorescence. Crystallography of liganded L5* reveals a 2:1 protein:ligand complex with inclusive C2 symmetry, where MG is almost entirely encapsulated between an antiparallel arrangement of the two VL domains. Unliganded L5* VL domains crystallize as a similar antiparallel VL/VL homodimer. The complementarity-determining regions are spatially oriented to form novel VL/VL and VL/ligand interfaces that tightly constrain a propeller conformer of MG. Binding equilibrium analysis suggests highly cooperative assembly to form a very stable VL/MG/VL complex, such that MG behaves as a strong chemical inducer of dimerization. Fusion of two VL domains into a single protein tightens MG binding over 1000-fold to low picomolar affinity without altering the large binding enthalpy, suggesting that bonding interactions with ligand and restriction of domain movements make independent contributions to binding. Fluorescence activation of a symmetrical fluorogen provides a selection mechanism for the isolation and directed evolution of ternary complexes where unnatural symmetric binding interfaces are favored over canonical antibody interfaces. As exemplified by L5*, these self-reporting complexes may be useful as modulators of protein association or as high-affinity protein tags and capture reagents.  相似文献   
160.
Penicillium spp. are well known to produce a variety of beneficial metabolites for plant growth and survival, as well as they defend their hosts from attack of certain pathogens. In this study, effects of culture filtrate of different Penicillium spp. were tested on tomato seeds. On the whole, presoaking of seeds in the filtrates of the nine Penicillium isolates tested significantly increased seed germination when compared with the control seeds. Cultural extracts of P. expansum and P. bilaii were highly effective in growth promotion up to 90%. It was also observed that P. implicatum and P. oxalicum significantly enhanced the root growth in tomato seedling as compared to other species. In case of shoot length, P. verrucosum (3.38 cm), P. granulatum (2.81 cm) and P. implicatum (2.62 cm) were effective. P. implicatum was quite promising in increasing shoot and root length in tomato seedlings, while P. simplicissimum and P. citrinum were less effective on seedling growth. The plant growth-promoting ability of Penicillium strains may help in growth promotion in other plants and crops. Penicillium spp. are already known for producing various mycotoxins and enzymes. Plant growth-promoting ability of Penicillium spp. will open new aspects of research and investigations. The role of Penicillium spp. in tomato plant growth requires further exploration.  相似文献   
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