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31.
32.
Verrucous carcinoma in association with hypertrophic lichen planus   总被引:1,自引:0,他引:1  
Neoplastic transformation of lichen planus is a rare event. However, squamous cell carcinoma may develop in 0.3%–3% of patients with the oral form of the disease. On the other hand, less than 30 cases arising in cutaneous lichen planus have been reported, and only four cases of verrucous carcinoma in association with either form, one with an oral lesion and three with cutaneous lesions (one hypertrophic and one ulcerative).
This report describes the unusual progression of a hypertrophic lichen planus plaque of the right leg to a verrucous carcinoma in a 40-year-old woman.  相似文献   
33.
PURPOSE: To develop a method for efficient automatic correction of slow-varying nonuniformity in MR images. MATERIALS AND METHODS: The original MR image is represented by a piecewise constant function, and the bias (nonuniformity) field of an MR image is modeled as multiplicative and slow varying, which permits to approximate it with a low-order polynomial basis in a "log-domain." The basis coefficients are determined by comparing partial derivatives of the modeled bias field with the original image. RESULTS: We tested the resulting algorithm named derivative surface fitting (dsf) on simulated images and phantom and real data. A single iteration was sufficient in most cases to produce a significant improvement to the MR image's visual quality. dsf does not require prior knowledge of intensity distribution and was successfully used on brain and chest images. Due to its design, dsf can be applied to images of any modality that can be approximated as piecewise constant with a multiplicative bias field. CONCLUSION: The resulting algorithm appears to be an efficient method for fast correction of slow varying nonuniformity in MR images.  相似文献   
34.
Abstract. A group of 41-year-old hypertensive men (n = 35, blood pressure (BP) 149.9 ± 2.1/ 98.9 ± 1.1 mmHg, mean ± SEM) who had never received treatment for their condition were compared with hypertensive women of the same age (n = 18, BP 155.9 ± 4.3/ 98.1 ± 1.6 mmHg) with comparable body mass index (BMI. 25.9 ± 0.5 vs. 24.9 ± 4.5 kg m?2) who, also, had never received treatment. The lipid profile was more atherogenic in the men, with lower HDL cholesterol (1.21 ± 0.04 vs. 1.38 ± 0.06 mmol l?1 P = 0.04), higher total cholesterol (6.04 ± 0.14 vs. 5.54 ± 0.18 mmol l?1. P = 0.04) and triglycerides (1.80 ± 0.16 vs. 0.96 ± 0.10 mmol l?1, P < 0.001). The hypertensive men had higher haemoglobin (P < 0.001) and haematocrit. Plasma catecholamines were inversely related to BMI in the women only (r = ?0.52, P < 0.05 for both noradrenaline and adrenaline). Women with BMI above 25 kg m?2 had significantly lower arterial plasma adrenaline and noradrenaline than those with BMI below 25 kg m?2 (28 ± 5 vs. 78 ± 16 pg ml?1, P < 0.01 and 101 ± 17 vs. 206 ± 33 pg ml?1, P < 0.01 respectively). A negative curvelinear relationship appeared between arterial adrenaline and insulin (r = 0.49, P= 0.05). These results suggest a male propensity for athero-thrombogenic risk factors in otherwise comparable hypertensive subjects. A close relationship between metabolic risk factors within the normal range seems to exist even in hypertensive women. The decreased sympathetic activity at rest in the obese hypertensive women indicates different pathophysiological mechanism for hypertension in lean and obese. Decreased sympathetic activity and thus reduced energy expenditure, promotes a risk for weight gain, and could explain the inverse relationship between insulin and adrenaline.  相似文献   
35.
Summary. In this inter-rater agreement study of antenatal and neonatal variables collected in a large teaching obstetric unit, information routinely collected by hospital staff was compared with that collected by a specially trained physician and a social worker. Agreement between the two sources of data was evaluated using kappa statistics and intraclass correlation coefficients. Excellent agreement was observed for some variables such as maternal and newborn anthropometric measures, and previous birthweight, but there was poor agreement for others such as indicators of physical activity, work during pregnancy and blood pressure measures. Some of the limitations are due to problems in phrasing questions, patients' recall, interviewer bias and abstracting data. We recommend that epidemiological studies should always include a reliability component, proper standardization of personnel and instruments and include, when published, validity data and examples of questions used.  相似文献   
36.

Objective

To evaluate the antimicrobial activity of Actinomycetes species isolated from marine environment.

Methods

Twenty one strains of Actinomycetes were isolated from samples of Royapuram, Muttukadu, Mahabalipuram sea shores and Adyar estuary. Preliminary screening was done using cross-streak method against two gram-positive and eight gram-negative bacteria. The most potent strains C11 and C12 were selected from which antibacterial substances were extracted. The antibacterial activities of the extracts were performed using Kirby-Bauer disc diffusion method. Molecular identification of those isolates was done.

Results

All those twenty one isolates were active against at least one of the test organisms. Morphological characters were recorded. C11 showed activity against Staphylococcus species (13.0±0.5 mm), Vibrio harveyi (11.0±0.2 mm), Pseudomonas species (12.0±0.3 mm). C12 showed activity against Staphylococcus species (16.0±0.4 mm), Bacillus subtilis (11.0±0.2 mm), Vibrio harveyi (9.0±0.1 mm), Pseudomonas species (10.0±0.2 mm). 16S rRNA pattern strongly suggested that C11 and C12 strains were Streptomyces species.

Conclusions

The results of the present investigation reveal that the marine Actinomycetes from coastal environment are the potent source of novel antibiotics. Isolation, characterization and study of Actinomycetes can be useful in discovery of novel species of Actinomycetes.  相似文献   
37.
Background: Acute kidney injury (AKI) with renal replacement therapy (RRT) is rare in trauma patients. The primary aim of the study was to assess incidence, mortality and chronic RRT dependency in this patient group. Methods: Adult trauma patients with AKI receiving RRT at a regional trauma referral center over a 12‐year period were retrospectively reviewed. Results: Population‐based incidence of post‐traumatic AKI with RRT was 1.8 persons per million inhabitants per year (p.p.m./year) [95% confidence the interval (CI) 1.5–2.1 p.p.m./year]. In trauma patients admitted to hospital, incidence was 0.5‰ (95% CI 0.3–0.7‰) of those treated in intensive care unit (ICU), it was 8.3% (95% CI 5.9–10.8%). The median age was 46 years. Odds ratio (OR) for post‐traumatic AKI requiring RRT was higher in males than in females in general population (OR 5.6, 95% CI 2.2–14.0), and in trauma patients admitted to hospital (OR 4.4, 95% CI 1.9–10.3) and ICU (OR 4.5, 95% CI 1.9–10.7). The in‐hospital mortality rate was 24% (95% CI 11–37%), 3‐month mortality 36% (95% CI 21–51%) and 1‐year mortality 40% (95% CI 25–55%). Age was a risk factor for death after 1 year, with 57% (95% CI 7–109%) increased risk for each 10 years added. None of the survivors was dialysis‐dependent 3 months or 1 year after trauma. Conclusion: AKI in trauma patients requiring RRT was rare in this single‐center study. More males than females were affected. Mortality was modest, and renal recovery was excellent as none of the survivors became dependent on chronic RRT.  相似文献   
38.
Humans can determine image quality instantly and intuitively, but the mechanism of human perception of image quality is unknown. The purpose of this work was to identify the most important quantitative metrics responsible for the human perception of digital image quality. Digital images from two different datasets—CT tomography (MedSet) and scenic photographs of trees (TreeSet)—were presented in random pairs to unbiased human viewers. The observers were then asked to select the best-quality image from each image pair. The resulting human-perceived image quality (HPIQ) ranks were obtained from these pairwise comparisons with two different ranking approaches. Using various digital image quality metrics reported in the literature, we built two models to predict the observed HPIQ rankings, and to identify the most important HPIQ predictors. Evaluating the quality of our HPIQ models as the fraction of falsely predicted pairwise comparisons (inverted image pairs), we obtained 70–71% of correct HPIQ predictions for the first, and 73–76%for the second approach. Taking into account that 10–14% of inverted pairs were already present in the original rankings, limitations of the models, and only a few principal HPIQ predictors used, we find this result very satisfactory. We obtained a small set of most significant quantitative image metrics associated with the human perception of image quality. This can be used for automatic image quality ranking, machine learning, and quality-improvement algorithms.  相似文献   
39.
BackgroundCholera, a severe acute watery diarrhea caused by Vibrio cholerae is endemic in Nigeria with most cases occurring in the rural areas. In South West Nigeria, some individuals resort to alternative treatments such as Ogi-tutu, Psidium guajava and Vernonia amygdalina during infections. The effectiveness of these alternatives in the prevention and treatment of V. cholerae infection requires experimental investigation.ObjectiveThis study was designed to investigate the ameliorative effects of Ogi-tutu, Vernonia amygdalina and Psidium guajava on intestinal histopathology of experimental mice infected with V. cholerae.MethodsPreliminary investigation of in vitro vibriocidal activities of these alternatives were carried out using agar cup diffusion assay. For ameliorative effects, adult mice were inoculated with 100 µl (106 cells) of Vibrio cholerae and dosed at 0 h (immediate prevention) and 4 h (treatment of infection) and their intestines were histopathologically evaluated.ResultsThe histopathological changes were the same irrespective of the treated groups, but the lesions varied in extent and severity. The ameliorative effects in decreasing order were V. amygdalina > P. guajava > Ogi-tutu.ConclusionV. amygdalina gave the best ameliorative effects in the prevention and treatment of V. cholerae infection.  相似文献   
40.
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