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1.
The aim is to compare the mean values of the in vivo electrical characteristics of bioiogical active points (BAPs) with those of the surrounding human skin. The impedance measurements at BAPs and on the surrounding skin are carried out in vivo on ten young, healthy people. The results of the measurements show that the BAP resistance RP is smaller, and the capacitance CP is higher, than the corresponding values for skin, RS and CS, respectively, these differences are larger at low frequencies (at f=3 Hz, RS/RP=3.19 and CP/CS=3.2). The mean values of the impedance measurements at the BAPs are different from those measured on the skin. The dependence of RP and CP on the pressing force, in the range of about 1–5 N, for the BAPs, has a smaller slope than that observed for the surrounding skin. An equivalent circuit for the BAPs is proposed that describes sufficiently well the experimental results obtained. These results show that the large dispersion in the observed impedance characteristics of the human body measurements in different body regions can be related to the influence of the BAPs present under the electrodes.  相似文献   
2.
Background and Aim: Development of hepatic fibrosis is a complex process that involves oxidative stress (OS) and an altered balance between pro‐ and anti‐apoptotic molecules. Since Bcl‐2 overexpression preserves viability against OS, our objective was to address the effect of Bcl‐2 overexpression in the hepatic stellate cells (HSC) cell‐line CFSC‐2G under acetaldehyde and H2O2 challenge, and explore if it protects these cells against OS, induces replicative senescence and/or modify extracellular matrix (ECM) remodeling potential. Methods: To induce Bcl‐2 overexpression, HSC cell line CFSC‐2G was transfected by lipofection technique. Green fluorescent protein‐only CFSC‐2G cells were used as a control. Cell survival after H2O2 treatment and total protein oxidation were assessed. To determine cell cycle arrest, proliferation‐rate, DNA synthesis and senescence were assessed. Matrix metalloproteinases (MMP), tissue‐inhibitor of MMP (TIMP), transglutaminases (TG) and smooth muscle a‐actin (α‐SMA) were evaluated by western blot in response to acetaldehyde treatment as markers of ECM remodeling capacity in addition to transforming growth factor‐β (TGF‐β) mRNA. Results: Cells overexpressing Bcl‐2 survived ≈ 20% more than control cells when exposed to H2O2 and ≈ 35% proteins were protected from oxidation, but Bcl‐2 did not slow proliferation or induced senescence. Bcl‐2 overexpression did not change α‐SMA levels, but it increased TIMP‐1 (55%), tissue transglutaminases (tTG) (25%) and TGF‐β mRNA (49%), when exposed to acetaldehyde, while MMP‐13 content decreased (47%). Conclusions: Bcl‐2 overexpression protected HSC against oxidative stress but it did not induce replicative senescence. It increased TIMP‐1, tTG and TGF‐β mRNA levels and decreased MMP‐13 content, suggesting that Bcl‐2 overexpression may play a key role in the progression of fibrosis in chronic liver diseases.  相似文献   
3.
Digestive surgeons should form part of the multidisciplinary team managing patients with oropharyngeal dysphagia. These patients can be diagnosed through clinical methods and complementary investigations such as videofluoroscopy and pharyngoesophageal manometry. These techniques also allow specific treatment to be selected. Up to one-third of patients with dysphagia suffer from malnutrition as a result of alterations in food bolus transport. Furthermore, up to two-thirds show alterations in swallowing safety (penetrations and aspirations, especially when swallowing liquids), as well as a high risk of respiratory infections and aspiration pneumonia. Increasing food bolus viscosity to 3500-4000 mPas (pudding viscosity) improves the effectiveness of swallowing and reduces the risk of aspirations. Botulinic toxin injection in the upper esophageal sphincter is indicated in patients with spasticity of neuromuscular origin. Cricopharyngeal myotomy is the basis of treatment for Zenker's diverticulum and is also indicated in patients with alterations in the upper esophageal sphincter and preserved oropharyngeal motor response.  相似文献   
4.

Ethnopharmacological relevance

Cyrtopodium macrobulbon (“cañaveral”) has been long used in Mexican traditional medicine for the treatment of painful urinary ailments (“mal de orin”) in men. This study was conducted (i) to establish the potential acute toxicity and the antinociceptive activity of some preparations of Cyrtopodium macrobulbon, in order to demonstrate its preclinical efficacy for treating symptoms of “mal de orin”; and (ii) to determine the chemical composition and quality control parameters of this medicinal orchid.

Materials and methods

The antinociceptive effect was assessed using the acetic acid-induced writhing and the hot-plate tests. Investigation of the acute toxicity was accomplished by the Lorke method. The organic extract (OE) was subjected to conventional phytochemical study using chromatographic conventional procedures. The volatile components profile of the species was accomplished via GC–MS analysis of HS-SPME-adsorbed compounds. Furthermore, an HPLC method to quantify ephemeranthol B (10) was developed and validated according to the International Conference on Harmonization Guidelines. Microscopic anatomy studies were performed using light and scanning electron microscopies. Finally, a potential distribution map was generated using the MaxEnt modeling method.

Results

AE and OE were not toxic to mice since the LD50 was higher than 5000 mg/kg. OE was only active in the acetic acid-induced writhing assay at the doses of 100 and 316 mg/kg. Conventional phytochemical analysis of OE led to the isolation and characterization of n-hexacosyl-trans-p-coumarate (1), n-octacosyl-trans-p-coumarate (2), n-triacontyl-trans-p-coumarate (3), 4-methoxy-benzyl alcohol (4), 4-hydroxybenzaldehyde (5), 1,5,7-trimethoxy-9,10-dihydrophenanthrene-2,6-diol (6), confusarin (7), gigantol (8), batatasin III (9), and ephemeranthol B (10). The major volatile components identified by HS-SPME analysis were 6,10,14-trimethyl-2-pentadecanone, eucalyptol (11), and isobornyl formate. An HPLC analytical method for the quantification of compound 10 in the plant was developed and fully validated for selectivity, accuracy, and precision. The microscopic studies revealed that the epidermal tissue displayed a layer of enlarged, crenate and cell thin-walled cells with a thickened cuticle; these cells are described for first time for this species. The potential distribution map generated revealed that this species is widespread in Mexico from Sinaloa to Merida states.

Conclusions

The results of the pharmacological studies tend to support the traditional use of Cyrtopodium macrobulbon for “mal de orin”; the presence of compounds 8, 9, and 11 with known antinociceptive activity might be related with the pharmacological effect demonstrated. The HPLC and microscopic analyses developed in this work will be valuable tools for quality control purposes for this plant.  相似文献   
5.

Purpose

To evaluate the effect of thiamine administration on metabolic profile, cytokines and inflammatory markers in drug-naïve patients with type 2 diabetes mellitus (T2DM).

Methods

A randomized, double-blind, placebo-controlled, pilot-scale clinical trial was carried out in 24 patients with T2DM. Twelve subjects received thiamine orally (150 mg), once daily during a fasting state for 1 month. An additional 12 patients (control group) were given placebo for the same period of time. Before and after the intervention, fasting glucose, A1C, creatinine, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, very low-density lipoprotein, high-sensitive C-reactive protein, interleukin 6, tumor necrosis factor-alpha, leptin and adiponectin levels were estimated. Wilcoxon’s signed-rank and Mann–Whitney U test were used for statistical analyses.

Results

There were significant decreases in glucose (6.7 ± 1.0 mmol/l vs. 6.0 ± 1.0 mmol/l, p = 0.024) before and after the intervention, respectively, and leptin concentrations (32.9 ± 13.3 ng/ml vs. 26.9 ± 12.8 ng/ml, p = 0.027) before and after the intervention, respectively, with thiamine administration. There were no changes with the rest of the measurements.

Conclusions

Thiamine administration for 1 month decreased glucose and leptin concentrations in drug-naïve patients with T2DM.
  相似文献   
6.
In profiling of health care providers, distinguishing extreme behavior from random variation with incomplete risk adjustment requires multiple observations on each profiling unit. Unlike typical health care delivery system studies, the US Department of Veterans Affairs (VA) information system does provide longer time series of data at individual, institutional and system levels. This information resource allows us to develop incisive profiling analyses that isolate and highlight system wide improvements and institution-specific profiles in the context of risk adjustments using several covariates. This is illustrated here in the context of substance abuse care. One common process monitor for systems delivering substance abuse care is follow-up outpatient care within a certain number of days after inpatient substance abuse discharges. The VA system provides ten years of such data, at the individual level, and we employ this to build hierarchical models that profile providers within the system. Our models use logistic regression, longitudinal random effects models at the individual patient level, combined with simple time series models of institutional effects across years. This structure effectively captures variability across hospitals within each year as well as systematic dependencies within hospitals from year to year. Analysis depends on Markov chain Monte Carlo methods to derive posterior inferences for all parameters. Results indicate significant system wide improvement in the monitor in addition to large amounts of variation in this improvement across medical centers. Covariates such as age of patient, VA treatment priority, and diagnoses (where psychotic patients have lower return rates) help to illustrate important potential new health policy interventions and the outcomes of previous interventions.  相似文献   
7.
8.
We report the results of long term bio-assays on microorganism colonization of mine tailings samples, taken from the Valenciana mine tailings (Guanajuato, Mexico), under stable laboratory conditions (humidity, temperature, light exposure). In order to identify the main metabolic groups of the potentially colonizing microorganisms and the implications of their growth on the main tailing’s characteristics related to biological succession, organic matter (OM) content, cationic exchange capacity (CEC), and pH values were measured as the colonization took place. We observe that photosynthetic biofilms (cyanobacteria, green algae, and diatoms) successfully colonize the mine tailings samples as pioneers; moreover, bacteria, yeast and fungi were also identified. Biofilm colonization significantly improved the OM contents, whereas the pH value is not modified during the entire observed colonization process. The results suggest that biofilms are useful during the first steps of the mine tailings remediation. This is the first report of microalgae and cyanobacteria grown of on tailings samples obtained from a semiarid region.  相似文献   
9.
10.
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