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11.
Treponema denticola has been associated with gingivitis and chronic periodontitis. The aim of this study was to identify Treponema denticola in subgingival samples using PCR technology and to correlate it with clinical diagnosis of subjects. The study was carried out on seventy patients (20-84 years of age; mean age, 45.06 +/- 12.58) of which 22 individuals with no detectable gingivitis or periodontitis, 4 subjects with chronic gingivitis and 44 subjects with chronic periodontitis. Subgingival plaque samples were collected from five sites in each patient. DNA was extracted from the samples using QIAamp DNA Mini Kit (QIAGEN). Treponema denticola and other four periodontopathogens were found using multiplex polymerase chain reaction followed by a reverse hybridization. The relationship between clinical diagnoses and detection of Treponema denticola was determined with Fisher exact test. The results showed significant differences between diagnostic groups regarding subject proportion. Treponema denticola was detected in 2 out of 22 subjects with no detectable gingivitis or periodontitis, 2 out of 4 subjects with chronic gingivitis, and 40 out of 44 subjects with chronic periodontitis. Our findings suggest that Treponema denticola is closely connected to the initiation and progression of periodontal disease.  相似文献   
12.
Mammalian cell culture systems are used predominantly for the production of therapeutic monoclonal antibody (mAb) products. A number of alternative platforms, such as Pichia engineered with a humanized N-linked glycosylation pathway, have recently been developed for the production of mAbs. The glycosylation profiles of mAbs produced in glycoengineered Pichia are similar to those of mAbs produced in mammalian systems. This report presents for the first time the comprehensive characterization of an anti-human epidermal growth factor receptor 2 (HER2) mAb produced in glycoengineered Pichia, and a study comparing the anti-HER2 from Pichia, which had an amino acid sequence identical to trastuzumab, with trastuzumab. The comparative study covered a full spectrum of preclinical evaluation, including bioanalytical characterization, in vitro biological functions, in vivo anti-tumor efficacy and pharmacokinetics in both mice and non-human primates. Cell signaling and proliferation assays showed that anti-HER2 from Pichia had antagonist activities comparable to trastuzumab. However, Pichia-produced material showed a 5-fold increase in binding affinity to FcγIIIA and significantly enhanced antibody dependent cell-mediated cytotoxicity (ADCC) activity, presumably due to the lack of fucose on N-glycans. In a breast cancer xenograft mouse model, anti-HER2 was comparable to trastuzumab in tumor growth inhibition. Furthermore, comparable pharmacokinetic profiles were observed for anti-HER2 and trastuzumab in both mice and cynomolgus monkeys. We conclude that glycoengineered Pichia provides an alternative production platform for therapeutic mAbs and may be of particular interest for production of antibodies for which ADCC is part of the clinical mechanism of action.Key words: glycoengineered Pichia, anti-HER2, trastuzumab, xenograft, PK, ADCC  相似文献   
13.
This study investigates the consequences of inhibition of adipose tissue lipolysis on skeletal muscle substrate use. Ten subjects were studied at rest and during exercise and subsequent recovery under normal, fasting conditions (control trial, CON) and following administration of a nicotinic acid analog (low plasma free fatty acid trial, LFA). Continuous [U-13C]palmitate and [6,6-2H2]glucose infusions were applied to quantify plasma free fatty acid (FFA) and glucose oxidation rates and to estimate intramuscular triacylglycerol (IMTG) and glycogen use. Muscle biopsies were collected to measure 1) fiber type-specific IMTG content; 2) allosteric regulators of hormone-sensitive lipase (HSL), glycogen phosphorylase, and pyruvate dehydrogenase; and 3) the phosphorylation status of HSL at Ser563 and Ser565. Administration of a nicotinic acid analog (acipimox) substantially reduced plasma FFA rate of appearance and subsequent plasma FFA concentrations (P < 0.0001). At rest, this substantially reduced plasma FFA oxidation rates, which was compensated by an increase in the estimated IMTG use (P < 0.05). During exercise, the progressive increase in FFA rate of appearance, uptake, and oxidation was prevented in the LFA trial and matched by greater IMTG and glycogen use. Differential phosphorylation of HSL or relief of its allosteric inhibition by long-chain fatty acyl-CoA could not explain the increase in muscle TG use, but there was evidence to support the contention that regulation may reside at the level of the glucose-fatty acid cycle. This study confirms the hypothesis that plasma FFA availability regulates both intramuscular lipid and glycogen use in vivo in humans.  相似文献   
14.
Concentrations of (E,E)-farnesol needed to inhibit germ tube formation were determined for Candida albicans strains A72 and SC5314 by using six different conditions known to trigger germination. For defined media, 1 to 2 microM farnesol was sufficient. However, with serum at 2 to 20%, up to 250 microM farnesol was required. Farnesol blocked germ tube formation but did not block elongation of existing germ tubes.  相似文献   
15.
Thermally-induced fluctuations of individual phospholipids in a bilayer lipid membrane (BLM) are converted into collective motions due to the intermolecular interactions. Here, we demonstrate that transbilayer stochastic pores can be generated via collective thermal movements (CTM). Using the elastic theory of continuous media applied to smectic-A liquid crystals, we estimate the pore radius and the energetic requirements for pore appearance. Three types of thermally-induced transbilayer pores could be formed through BLMs: open and stable, open and unstable, and closed. In most of the situations, two open and stable pores with different radii could be generated. Notably, the two pores have the same generation probability. Unstable pores are possible to appear across thin bilayers that contain phospholipids with a large polar headgroup. Closed pores are present throughout the cases that we have inspected. The effects of hydrophobic thickness, polar headgroup size of phospholipids, temperature, surface tension, and elastic compression on the pore formation and pore stability have been examined as well.  相似文献   
16.
Reduced skeletal muscle free coenzyme A (CoASH) availability may decrease the contribution of fat oxidation to ATP production during high-intensity, submaximal exercise or, alternatively, limit pyruvate dehydrogenase complex (PDC) flux and thereby carbohydrate oxidation. Here we attempted to increase the muscle CoASH pool in humans, via pantothenic acid and cysteine feeding, in order to elucidate the role of CoASH availability on muscle fuel metabolism during exercise. On three occasions, eight healthy male volunteers (age 22.9 ± 1.4 yr, body mass index 24.2 ± 1.5 kg/m(2)) cycled at 75% maximal oxygen uptake (Vo(2max)) to exhaustion, followed by a 15-min work output performance test. Muscle biopsies were obtained at rest, and after 60 min and 91.3 ± 3.1 min of exercise (time to exhaustion on baseline visit) on each occasion. Two weeks following the first visit (baseline), 1 wk of oral supplementation with either 3 g/day of a placebo control (glucose polymer; CON) or 1.5 g/day each of d-pantothenic acid and l-cysteine (CP) was carried out prior to the second and third visits in a randomized, counterbalanced, double-blind manner, leaving a 3-wk gap in total between each visit. Resting muscle CoASH content was not altered by supplementation in any visit. Following 60 min of exercise, muscle CoASH content was reduced by 13% from rest in all three visits (P < 0.05), and similar changes in the respiratory exchange ratio, glycogenolysis (~235 mmol/kg dry muscle), PCr degradation (~57 mmol/kg dry muscle), and lactate (~25 mmol/kg dry muscle) and acetylcarnitine (~12 mmol(.)kg/dry muscle) accumulation was observed during exercise when comparing visits. Furthermore, no difference in work output was observed when comparing CON and CP. Acute feeding with pantothenic acid and cysteine does not alter muscle CoASH content and consequently does not impact on muscle fuel metabolism or performance during exercise in humans.  相似文献   
17.
The biosorption of Pb(II), Cd(II), and Co(II), respectively, from aqueous solution on green algae waste biomass was investigated. The green algae waste biomass was obtained from marine green algae after extraction of oil, and was used as low-cost biosorbent. Batch shaking experiments were performed to examine the effects of initial solution pH, contact time and temperature. The equilibrium biosorption data were analyzed using two isotherm models (Langmuir and Freundlich) and two kinetics models (pseudo-first order and pseudo-second order). The results indicate that Langmuir model provide best correlation of experimental data, and the pseudo-second order kinetic equation could best describe the biosorption kinetics of considered heavy metals.  相似文献   
18.
The relationship between different species of oral Treponemas and inflammation in periodontal disease progression is complex. The purpose of this study was to analyze and compare the subgingival plaque samples collected from periodontally healthy subjects and from chronic gingivitis and periodontitis patients in order to detect the presence of T. denticola, T. pectinovorum, T. socranskii and T. vincentii using nested-PCR technology. After DNA extraction from the samples using QIAmp DNA Mini Kit (QIAGEN, the four Treponema species were determined with nested-polymerase chain reaction which requires two sets of primers to amplify a specific DNA fragment in two separate runs of PCR. Pearson chi-square was implemented to compare the three groups as to the presence of four Treponema species. Results of this investigation showed significant differences between groups regarding subject proportion of T. denticola, T. socranskii, T. pectinovorum, T. vincentii, with a higher percentage of patients from associated-disease groups of patients harboring these four species than healthy subjects. These differences were more pronounced in presence of Treponema denticola and Treponema socranskii. Our findings suggest that Treponema denticola and Treponema socranskii concurrent presence indicate more accurately the association with chronic gingivitis and periodontitis.  相似文献   
19.
Under positive osmotic stress, a greater lipid vesicle swells to a critical diameter, when suddenly a transbilayer pore appears and grows to a maximum radius, then decreases and finally disappears. An amount of liquid was leaked out through the pore and the vesicle returns to the initial state and can start another cycle. This is a pulsatory lipid liposome. In this paper, we have considered the problem of such liposomes. We have obtained the condition that a pulsatory liposome to run an a priori settled number of cycles. The length time of each cycle and its activity life was calculated. Also, we have calculated the quantities of solute leaked out through a pore in each cycle. The pulsatory liposome may be regarded as a biotechnological device to dose drugs at fixed intervals time.  相似文献   
20.
Indiscriminate discharge of pharmaceutical waste into the aquatic ecosystem may pose serious health challenges to aquatic biota. The effect of acute exposure to ibuprofen was evaluated using changes in behaviour and haematological parameters under static bio-assay method in Clarias gariepinus. Test specimens were exposed to acute concentrations of ibuprofen (0.28, 0.33, 0.38, 0.43 and 0.48 mg l?1) for 24, 48, 72 and 96 h durations respectively. Behavioural and phenotypic changes were observed in surviving fish. There were significant (p < 0.05) concentration and duration-dependent increases in erythrocyte (RBC), haemoglobin (Hb), pack cell volume (PCV) and leukocytes (WBC) in treated fish compared to the control. Insignificant decreases (p > 0.05) in mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were observed in treated fish compared to the control. Ibuprofen elicited dose and duration- dependent decrease in neutrophil counts with the decreases being significant (p < 0.05) in the higher doses of 0.43 and 0.48 mg l?1. Ibuprofen did not elicit any significant changes in monocytes, basophils and eosinophils. Changes observed in this study showed that ibuprofen negatively affected the health of the fish and we recommend that discharge of ibuprofen into the aquatic environment should be monitored and controlled.  相似文献   
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