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101.
102.
正This study was to investigate whether working in conditions of elevated concentrations of mine gases(CO_2,CO,CH_4,DMS)and dust may result in oxidative stress.Coal miners(n=94)from the Velenje Coal mine who were arranged into control group and three groups according to a number of consecutive working days.8-isoprostane as a biological marker of oxidative stress was measured  相似文献   
103.
A combination of antimicrobial and endotoxin-neutralizing activities is desired in order to prevent progression from infection to sepsis due to the release of lipopolysaccharide from dying gram-negative bacteria. Lipopolyamines have emerged as a new type of endotoxin-neutralizing compound, but their antimicrobial activity has not been investigated. We synthesized a series of 10 oleoylamines differing in the polyamino head group, particularly in the number and separation between nitrogen atoms and the position of the oleoyl moiety. Compounds showed activity against both gram-negative and gram-positive bacteria in the micromolar range. Compounds were able to provide penetration of ethidium bromide into bacteria, indicating effects on the bacterial membrane. Oleoylamines neutralized endotoxin in Limulus amoebocyte lysate assays and by neutralization of tumor necrosis factor alpha release in human blood. Comparison of biological activities of compounds identified structural properties responsible for antimicrobial activity, and quantitative structure-property relationship analysis provided a quantitative model for prediction of activity of oleoylamines.  相似文献   
104.
The aim of the present study was to evaluate different pharmaceutically acceptable excipients as permeation enhancers for a low permeability drug, amoxicillin. As a model for the intestinal epithelium excised rat jejunum, mounted in side-by-side diffusion cells, was used. Amoxicillin was actively transported across the intestine in the serosal-to-mucosal direction, but only if glucose was present at the mucosal side. This effect of glucose was abolished by a multridrug resistance associated protein (MRP) inhibitor benzbromarone (0.04 mM), but not by verapamil (0.2 mM). Among the tested pharmaceutically acceptable excipients only sodium lauryl sulfate (0.2 mg/ml) increased the permeability of amoxicillin in the mucosal-to-serosal direction, which was accompanying with the abolishment of the secretory oriented transport of amoxicillin. Other excipients (0.07 2mg/ml Pluronic F68, 0.2 mg/ml Lutrol F127, 0.2 mg/ml Cremophor EL or 0.2 mg/ml Carbopol 934) have no influence on the permeability of amoxicillin. The effect of sodium lauryl sulfate on the active secretion of amoxicillin was mainly attributed to the reversible cellular ATP depletion. We concluded that sodium lauryl sulfate can be considered as a relatively safe permeation enhancer for amoxicillin in drug delivery systems intended to improve oral bioavailability of this drug.  相似文献   
105.
The role of Demodex folliculorum in perioral dermatitis is not satisfactory explained. Our purpose was to assess the density of D. folliculorum in perioral dermatitis and evaluate the relationship of the mite count to previous therapy with topical steroids. A standardized skin surface biopsy of the chin was performed in 82 female patients with perioral dermatitis and in 70 control female subjects. Patients who received previous topical steroid therapy had a significantly higher mite density than the patients who had received no topical steroids (p<0.001). In the latter group of patients, the mite density did not differ significantly from that of the control group (p=0.629). Mite density increased significantly with the length of treatment with topical steroids (p<0.001). Our results suggest that increased density of D. folliculorum in perioral dermatitis is a secondary phenomenon, associated with topical steroid therapy.  相似文献   
106.
The aim of the present study was to analyze and compare Borrelia strains isolated from two different specimens obtained simultaneously from individual patients with Lyme borreliosis. Fifty such patients and 50 corresponding pairs of Borrelia isolates (100 low-propagated strains) were subjected to genotypic and phenotypic analysis, including pulsed-field gel electrophoresis for species identification and plasmid profile determination and protein profile electrophoresis for the assessment of the presence and molecular masses of separated proteins. The strains were isolated from two distinct skin lesions (12 patients), skin and blood (28 patients), skin and cerebrospinal fluid (8 patients), and blood and cerebrospinal fluid (2 patients). Out of 100 isolates, 63 were typed as B. afzelii and 37 as B. garinii. From each individual specimen only a single Borrelia species was cultured. Comparison of 50 Borrelia strain pairs isolated from two different specimens of an individual patient revealed that 12/50 (24%) patients were simultaneously infected with two different Borrelia strains; in 3/50 (6%) patients strains differed at the species level, in 4 out of the remaining 47 (9%) patients a strain difference in plasmid profile was established, while 5 out of the remaining 43 (11%) patient strain pairs differed in regard to the protein profiles of the two concurrently isolated strains. The results of the present study indicate that human patients with Lyme borreliosis may simultaneously harbor different B. burgdorferi sensu lato strains.  相似文献   
107.
108.
Background: Lower age at onset of schizophrenia has been traditionally associated with poorer response to treatment and less favourable prognosis. The aim of the study was to find out whether age at onset of schizophrenia is related to the dosage of typical neuroleptics in outpatients. Method: Age at onset was defined as age at first seeking of psychiatric help. Demographic, social and disease-related characteristics were studied in a group of 200 stable outpatients with schizophrenia (100 males and 100 females). Psychopathological symptoms were assessed with the Krawiecka Scale. Neuroleptic dosage was converted to milligrams of chlorpromazine equivalents and logarithmically transformed to obtain normal distribution. Results: Onset of schizophrenia occurred earlier in males than in females. The average dosage was 251.7 (SD 303.9) mg chlorpromazine equivalents. In a multivariate linear regression model, lower age at onset and higher sum of symptoms were related to the drug dosage. Conclusion: The results confirm the findings of other authors that patients with lower age at onset are less responsive to typical neuroleptics. Some of the patients with early onset would be more appropriately treated with atypical neuroleptics, which may have better therapeutic efficacy. Accepted: 3 September 1999  相似文献   
109.

Background

A modified theory of planned behaviour (acronym CASCADA) proposes that Conscious knowledge precedes a change in Attitude, which in turn precedes positive deviations from negative Subjective norms, intention to Change, perception of Agency to change, Discussion of possible action, and Action itself. We used this as a results chain to investigate gender-specific behaviour dynamics in chemical-free dengue prevention.

Methods

Secondary analysis of the Mexican arm of a cluster randomised controlled trial used household survey data on intermediate outcomes of dengue prevention behaviour. We used a matrix of odds ratios between outcomes, transformed to a symmetrical range (?1, 1), to compute fuzzy transitive closure of the results chain for control and intervention clusters, then for male and female respondents separately in each group. Transitive closure of a map computes the influence of each factor on each other factor, taking account of all influences in the system. Cumulative net influence was the sum of influences across the results chain.

Results

Responses of 5042 women and 1143 men in 45 intervention clusters contrasted with those of 5025 women and 1179 men in 45 control clusters. Control clusters showed a distal block (negative influence) in the results chain with a cumulative net influence of 0.88; intervention clusters showed no such block and a cumulative net influence of 1.92. Female control respondents, like the overall control picture, showed a distal block, whereas female intervention responses showed no such blocks (cumulative net influence 0.78 and 1.73 respectively). Male control respondents showed weak distal blocks. Male intervention responses showed several new negative influences and a reduction of cumulative net influence (1.38 in control and 1.11 in intervention clusters).

Conclusions

The overall influence of the intervention across the results chain fits with the trial findings, but is different for women and men. Among women, the intervention overcame blocks and increased the cumulative net influence of knowledge on action. Among men, the intervention did not reinforce prevention behaviour. This might be related to emphasis, during the intervention, on women’s participation and empowerment. The fuzzy transitive closure of the CASCADA map usefully highlights the differences between gender-specific results chains.

Trial registration

ISRCTN27581154.
  相似文献   
110.
Background  Up to now rejuvenating treatment of the hands has been challenging and results often disappointing.
Aims  To determine whether hyaluronic acid (HA) microdroplet placement into the dorsal hands has an impact on skin physiology and clinical appearance and whether there is any difference between stabilized HA (S-HA) and nonstabilized HA (NS-HA).
Patients/methods  The intra-individual comparison in 15 volunteers involved injection sessions at week 0, 4, and 8 with random assignment of left and right hand to either S-HA or NS-HA. Skin physiology parameters cutaneous elasticity, surface roughness, hydration, and transepidermal water loss (TEWL) were measured in vivo at weeks 0 (before treatment), 4 (before subsequent treatment), 12, and 24. Clinical hand assessment was carried out at weeks 0 and 12 by a blinded dermatologist.
Results  Intradermal injection of S-HA generated significant improvement in skin elasticity and surface roughness at week 12 compared to baseline. On the hands treated with NS-HA, there was a trend for improvement (not significant). While there was no significant difference in hydration and TEWL between both hands before treatment, at week 12 hands treated with S-HA displayed a significantly higher hydration level and lower TEWL compared to NS-HA treatment. Clinically S-HA proved to be significantly superior to NS-HA. At week 24 the observed effects started to return back toward baseline, with S-HA treatment still offering better results compared to the NS-HA.
Conclusions  Skin revitalization with injectable HA can improve clinical appearance and skin physiology parameters on the back of the hands. It has been shown that S-HA has better effects when compared with NS-HA.  相似文献   
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