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81.
Tolaasins are antimicrobial lipodepsipeptides. Here, we report the tolaasins-detoxifying properties of Microbacterium sp. K3-5 (K3-5). The detoxification of tolaasins by K3-5 was performed by hydrolyzation of cyclic structure of tolaasins depending on the tolaasin-K3-5 cell interaction. Our data suggest that the cyclic structure of tolaasins is critical for its interaction to target cells.  相似文献   
82.

Introduction

In this series of papers, we present a design of poly(methyl methacrylate) (PMMA) recycling system considering environmental impacts, chemical hazards, and resource availability. We applied life cycle assessment (LCA), environment, health, and safety (EHS) assessment as well as material flow analysis to the evaluation of the recycling system.

Purpose

Recycling systems for highly functional plastics such as PMMA have not been studied sufficiently. Along with the popularization of PMMA-containing products such as liquid crystal displays (LCDs), the use of PMMA is steadily increasing, which will result in more waste of PMMA in the next decades. In this study, pyrolysis process for recycling waste PMMA into methyl methacrylate (MMA) monomer was examined, considering not only general environmental impacts quantified by life cycle assessment but also local environment, health, and safety hazards, and raw material availability.

Methods

Process EHS hazards assessment was applied to quantify the local effects of the PMMA monomer recycling process. Process hazards are strongly connected with the hazardous properties of chemical substances and stream conditions within the process. Two alternative cooling methods exist, and their difference was analyzed by LCA and EHS assessment. Besides the process hazard, the availability of waste PMMA must be an important point for the feasibility of implementing the PMMA monomer recycling process. The available amount can be quantified by analyzing the material flow of PMMA-containing products. PMMA contained in LCDs as light guide panels was selected as a feasible source of waste PMMA, and the quantity of PMMA flows in the society was evaluated.

Results and discussion

In the case of PMMA, monomer recycling has less process hazard than the production of fresh MMA from crude oil. The implementation of circulated cooling water could significantly decrease the process hazard in PMMA pyrolysis attributable to chemical hazards. Material flow analysis revealed that the availability of waste PMMA shows a fluctuating trend in the next 20 years because of the sharp peak demand for LCD television sets. The fluctuation is strongly dependent on the lifetime of LCD television sets.

Conclusions

PMMA monomer recycling has a potential to reduce environmental impacts with a less process hazards than fresh MMA production from crude oil. The availability of waste PMMA has a strong relationship with the lifetime of LCD television sets. The multiple and comprehensive assessments can reveal various aspects of a process technology.  相似文献   
83.
84.
BACKGROUND: Although valproic acid (VPA) is used extensively for treating various kinds of epilepsies, it is well known that it causes neural tube and skeletal defects in both humans and animals. The amide and urea derivatives of the tetramethylcylcopropyl VPA analogue, N-methoxy-2,2,3,3-tetramethylcyclopropanecarboxamide (N-methoxy-TMCD) and 2,2,3,3-tetramethylcyclopropanecarbonylurea (TMC-urea), were synthesized and shown to have a more potent anticonvulsant activity than VPA. The objective of this study was to investigate the teratogenic effects of these compounds in NMRI mice. METHODS: Pregnant NMRI mice were given a single subcutaneous injection of either VPA, N-methoxy-TMCD, or TMC-urea at 1.8 and 3.6 mmol/kg on gestation day (GD) 8. Cesarean section was performed on GD 18. First, the live fetuses were examined to detect any external malformations, then their skeletons were double-stained for bone and cartilage and subsequently examined. RESULTS: Significant increases in fetal losses and neural tube defects were observed with administration of VPA at 3.6 mmol/kg when compared to the vehicle control. In contrast, upon cesarean section, there were no significant differences between either N-methoxy-TMCD or TMC-urea and the control groups for any parameter. Skeletal examination revealed that a number of the abnormalities were induced by VPA dose-dependently at high rates of incidence. These abnormalities were mainly at the axial skeletal level. However, lower frequencies of skeletal abnormality were observed with N-methoxy-TMCD and TMC-urea than with VPA. CONCLUSIONS: In addition to their more potent antiepileptic activity, these findings clearly indicate that N-methoxy-TMCD and TMC-urea are distinctly less teratogenic than VPA in NMRI mice.  相似文献   
85.
We investigated the effects of program design on 400-m sprint time by applying a Rating of Perceived Exertion (RPE) mathematical model to training performance. The subject was 24 years old and had been training for 9 years. His best performance in 400-m sprint competitions was 45.50 seconds. Body weight, resting heart rate, training time and RPE were monitored daily after training sessions. Similarly, performance in 400-m races was recorded 9 times during 2003. At the World Championships in Athletics in France, the subject's team placed eighth in the 1,600-m relay. The RPE mathematical model was able to predict changes in performance. Rate of matching was statistically significant (r(2) = 0.83, F ratio = 34.27, p < 0.001). Application of the RPE mathematical model to the design of a training program specific to the needs of a 400-m sprinter indicates a potentially powerful tool that can be applied to accurately assess the effects of training on athletic performance.  相似文献   
86.
87.

Background

The aims of this study were to determine the change of whole-serum N-glycan profile in ulcerative colitis (UC) patients and to investigate its clinical utility.

Methods

We collected serum from 75 UC patients at the time of admission and the same number of age/sex-matched healthy volunteers. Serum glycan profile was measured by comprehensive quantitative high-throughput glycome analysis and was compared with disease activity and prognosis.

Results

Out of 61 glycans detected, 24 were differentially expressed in UC patients. Pathway analysis demonstrated that highly sialylated multi-branched glycans and agalactosyl bi-antennary glycans were elevated in UC patients; in addition, the glycan ratio m/z 2378/1914, which also increased in UC, showed the highest Area under Receiver Operating Characteristic curve (0.923) for the diagnosis of UC. Highly sialylated multi-branched glycans and the glycan ratio m/z 2378/1914 were higher in the patients with total colitis, Clinical Activity Index >10, Mayo endoscopic score 3, or a steroid-refractory status. In particular, the glycan ratio m/z 2378/1914 (above median) was an independent prognostic factor for the need for an operation (hazard ratio, 2.67; 95% confidence interval, 1.04–7.84).

Conclusions

Whole-serum glycan profiles revealed that the glycan ratio m/z 2378/1914 and highly sialylated multi-branched glycans increase in UC patients, and are correlated with disease activity. The glycan ratio m/z 2378/1914 was an independent predictive factor of the prognosis of UC.  相似文献   
88.
Accumulating evidence indicates that metabolic dysfunction with visceral obesity is a major medical problem associated with the development of hypertension, type 2 diabetes (T2DM) and dyslipidemia, and ultimately severe cardiovascular and renal disease. Therefore, an effective anti-obesity treatment with a concomitant improvement in metabolic profile is important for the treatment of metabolic dysfunction with visceral obesity. Bofu-tsu-shosan (BOF) is one of oriental herbal medicine and is clinically available to treat obesity in Japan. Although BOF is a candidate as a novel therapeutic strategy to improve metabolic dysfunction with obesity, the mechanism of its beneficial effect is not fully elucidated. Here, we investigated mechanism of therapeutic effects of BOF on KKAy mice, a model of human metabolic disorders with obesity. Chronic treatment of KKAy mice with BOF persistently decreased food intake, body weight gain, low-density lipoprotein cholesterol and systolic blood pressure. In addition, both tissue weight and cell size of white adipose tissue (WAT) were decreased, with concomitant increases in the expression of adiponectin and peroxisome proliferator-activated receptors genes in WAT as well as the circulating adiponectin level by BOF treatment. Furthermore, gene expression of uncoupling protein-1, a thermogenesis factor, in brown adipose tissue and rectal temperature were both elevated by BOF. Intriguingly, plasma acylated-ghrelin, an active form of orexigenic hormone, and short-term food intake were significantly decreased by single bolus administration of BOF. These results indicate that BOF exerts a combinatorial favorable metabolic modulation including antihypertensive effect, at least partially, via its beneficial effect on adipose tissue function and its appetite-inhibitory property through suppression on the ghrelin system.  相似文献   
89.
Display of heterologous antigens on the cell surface is considered a useful technique for vaccine delivery by recombinant lactobacilli. In this study, two recombinant Lactobacillus acidophilus derivatives displaying Salmonella flagellin (FliC) were constructed using different anchor motifs. In one instance, the FliC protein was fused to the C-terminal region of a cell envelope proteinase (PrtP) and was bound to the cell wall by electrostatic bonds. In the other case, the same antigen was conjugated to the anchor region of mucus binding protein (Mub) and was covalently associated with the cell wall by an LPXTG motif. These two recombinant L. acidophilus cell surface displays resulted in dissimilar maturation and cytokine production by human myeloid dendritic cells. The surface-associated antigen was highly sensitive to simulated gastric and small intestinal juices. By supplementation with bicarbonate buffer and soybean trypsin inhibitor, the cell surface antigen was protected from proteolytic enzymes during gastric challenge in vitro. The protective reagents also increased the viability of the L. acidophilus cells upon challenge with simulated digestive juices. These results demonstrate the importance of protecting cells and their surface-associated antigens during oral immunization.  相似文献   
90.
Mitral valve closure may be aided by contraction of anterior leaflet (AL) cardiac myocytes located in the annular third of the leaflet. This contraction, observed as a stiffening of the annular region of the AL during isovolumic contraction (IVC), is abolished by beta-blockade (βB). Sub-threshold rapid pacing in the region of aorto-mitral continuity (STIM) also causes AL stiffening, although this increases the stiffness of the entire leaflet during both IVC and isovolumic relaxation (IVR). We investigated whether these contractile events share a common pathway or whether multiple AL contractile mechanisms may be present. Ten sheep had radiopaque-markers implanted: 13 silhouetting the LV, 16 on the mitral annulus, an array of 16 on the AL, and one on each papillary muscle tip. 4-D marker coordinates were obtained from biplane videofluoroscopy during control (C), βB (esmolol) and during βB+STIM. Circumferential and radial stiffness values for three AL regions (Annular, Belly, and free-Edge), were obtained from inverse finite element analysis of AL displacements in response to trans-leaflet pressure changes during IVC and IVR. βB+STIM increased stiffness values in all regions at both IVC and IVR by 35 ± 7% relative to βB (p<0.001). Thus, even when AL myocyte contraction was blocked by βB, STIM stiffened all regions of the AL during both IVC and IVR. This demonstrates the presence of at least two contractile systems in the AL; one being the AL annular cardiac muscle, involving a β-dependent pathway, others via a β-independent pathway, likely involving valvular interstitial cells and/or AL smooth muscle cells.  相似文献   
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