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71.
72.

Introduction

Nickel and cobalt allergy remain frequent in dermatitis patients. It is important to determine possible nickel and cobalt exposures at work as these may offer important information to regulators and physicians who perform patch testing. Clinical relevance of metal exposure is usually assessed by the treating physician via the medical history and by presentation of allergic contact dermatitis.

Objectives

To screen unused non-powered hand-held work tools for nickel and cobalt release by using colorimetric spot tests.

Materials & methods

A random selection of 200 non-powered hand-held work tools for sale in 2 retailers of home improvement and construction products were analyzed qualitatively for metal release using the colorimetric nickel and cobalt spot tests.

Results

Nickel release was identified from 5% of 200 work tools using the dimethylglyoxime (DMG) test. In 8 of 10, positive results were located to the metal ring that acts like a cuff and is located at the end of the grip. The positive DMG test results were not related to specific categories of work tools. The cobalt spot test gave no positive test reactions.

Conclusions

It appears that the proportion of work tools that release nickel, in amounts that may result in allergic nickel dermatitis, has decreased markedly, when results were compared with a Swedish study performed more than a decade ago. No cobalt release was detected but it should be underscored that hard-metal tools were not examined. Other sources of cobalt may explain the relatively high levels of cobalt allergy in dermatitis patients.  相似文献   
73.
In childhood, atopic dermatitis typically begins around 2--6 months of age. It is thought that the skin barrier dysfunction as well as allergic disease is important in the mechanism of atopic dermatitis. However, there are few reports of the skin barrier function in childhood. So we examined the relationship between the longitudinal surveys of the skin barrier function through the average projected area of corneocytes (APAc) and clinical findings in children from 1 to 12 months. As a result of examinations, APAc of cheek and upper arm in 1-month-old children is the same as those in adults, and APAc of cheek and upper arm decreases by 6 months of age. These results suggest that the skin barrier function decreases before or after the onset age of atopic dermatitis during childhood. Moreover, we examined APAc of children aged 0–5 for 1 year in the same nursery. APAc of upper arm in atopic dermatitis or atopic disposition has a significant difference compared with that of the other subjects in December. Furthermore, it was shown that change of APAc in the children under medical treatment was correlated with clinical findings. In conclusion, it was thought that the APAc shown as the index of skin barrier dysfunction is associated with the onset age of atopic dermatitis in childhood.  相似文献   
74.

Scope

Epidemiological data suggest that altered gut microbiota contributes to the development of atopic dermatitis (AD). The effect of an olive-derived antioxidant dietary fiber (OADF) in relieving AD symptoms in a murine model of 2,4-dinitrofluorobenzene (DNFB)-induced AD is examined and the effect of OADF in modulating host gut microbiota is explored.

Methods and results

Mice are fed with either standard diet or standard diet + OADF for 3 weeks prior to induction of AD and maintained on the same diet throughout the DNFB application period. Dietary OADF causes significant improvement of AD-like symptoms with reduced serum levels of immunoglobulin (Ig)E, interleukin (IL)-1β, IL-6, C-X-C motif ligand (CXCL)1, and increased serum levels of IL-10. OADF supplementation restore gut microbiota composition that are altered in AD mice. Specifically, OADF increases the proportion of intestinal bacteria (Ruminococcaceae UCG014, GCA900066575, UBA1819) associated with enhanced butyrate production, along with inhibiting Clostridiales vadin BB60 which are more prevalent in AD mice.

Conclusion

OADF modulates gut microbiota composition, improves cytokine profile and butyrate production influencing AD-associated immune response. Results highlight the importance of the gut-skin axis for the AD dietary therapeutic agents.  相似文献   
75.
The etiopathogenesis of bovine digital dermatitis (DD) is not well understood, but its risk factors on dairy farms have been studied extensively. The objective of this study was to identify associations between a DD risk score [determined by a DD risk assessment questionnaire (RAQ)] and DD prevalence (determined by an in-parlor M-score). We also investigated whether feedback for farmers on their DD management using the DD RAQ resulted in changes that decreased DD prevalence in their herds. The DD RAQ consisted of multiple-choice questions related to foot health, housing, and general management that were used to create a total risk score (TRS). In 2016 and 2018, the DD RAQ—together with a DD prevalence determination in the lactating herd—was used on 19 Dutch dairy farms from 1 veterinary practice. After each visit, farmers and their consulting veterinarians received a 1-page summary that identified herd-specific strengths and weaknesses in DD management. In 2018, the summary included suggestions for improvement. In 2019, farmers and veterinarians were contacted to ask whether the use of the DD RAQ and the 1-page summary had led them to implement changes in their DD management in 2016 and 2018. We tested the association between TRS and DD prevalence using linear mixed model analysis. The TRS ranged from 13 to 65% and 20 to 68% in 2016 and 2018, respectively. Herd DD prevalence ranged from 15 to 59% and 27 to 69% in 2016 and 2018, respectively. For both years, the DD RAQ identified that DIM, herd size, and breed were often present in a manner associated with increased risk for DD. The linear mixed model analysis identified that each 10-point increase in TRS was associated with an increase in herd DD prevalence of less than 1%. The association between TRS and herd DD prevalence was caused mainly by risk factors related to housing. We found no important relationship between change in TRS and change in DD prevalence between the 2 visits. Only a few farmers indicated some form of change in their DD management following a visit. Veterinarians in general said that they discussed the 1-page summaries and DD control with farmers during a routine visit, but the majority admitted a lack of follow-up. We propose that the DD RAQ could be used as a tool to start a discussion on DD control on farm, but simply undertaking a DD RAQ and providing a 1-page summary of the results was insufficient to initiate behavioral change that led to a decrease in DD prevalence.  相似文献   
76.
Skin is the largest organ of the body and is constantly exposed to physical, chemical, bacterial, and fungal challenges. It is well known that probiotics are helpful for specific disorders and different clinical studies have indicated that probiotics have special effects in cutaneous apparatus directly or indirectly that can be considerable from versatile aspects. Probiotic bacteriotherapy can have great potential in preventing and treating the skin diseases including eczema, atopic dermatitis, acne, and allergic inflammation or in skin hypersensitivity, UV-induced skin damage, wound protection, and as a cosmetic product. The current paper comprehensively reviews the different health effects of probiotics on the skin.  相似文献   
77.
Udder cleft dermatitis (UCD) is a skin lesion in dairy cattle mostly located at the anterior junction between the udder and the abdominal wall or between the front quarters. Relatively little is known about causative factors for UCD, and few studies have investigated prevalence and risk factors of UCD. Therefore, the aim of this study was to investigate the prevalence of UCD in a random sample of dairy herds with freestalls and milking parlors in a county of Sweden. Thirty dairy herds participated in the study. Each herd was visited once at milking, when every third cow was investigated for presence of UCD. Associations between UCD and milk production, breed, parity, days in milk, claw health, and udder health on the herd and cow levels were also investigated. In addition, a case-control study was performed in 6 herds with a high prevalence of UCD to investigate associations between udder conformation or mange and UCD. Udder cleft dermatitis was found in 18.4% of the 1,084 cows included in the study. The within-herd cow prevalence varied between zero and 39%, with an average of 18.5%. Risk factors for UCD at the herd level were a high proportion of Swedish Red cows and a high production level. At the cow level, breed, parity, and production level were identified as risk factors. The highest risk of having UCD was found in high-producing Swedish Red cows that had calved at least 3 times. Veterinary-treated clinical mastitis was associated with UCD, but cow composite somatic cell count was not. A strong anterior udder attachment was a protective factor, but signs of mange had no association with UCD. The primary cause of UCD is still unclear, and more research is needed to identify the best ways to prevent the development of this animal welfare problem.  相似文献   
78.
One of the problems that some industries, and more specifically cement industries, still have to deal with is the requirement to determine and control the content of some chromium, nickel and cobalt compounds due to their allergenic effects on human health (mainly cement dermatitis). This paper focuses on the quantification of total and soluble chromium, nickel and cobalt content in different materials used normally in the manufacturing of Spanish commercial cements (limestone, clay minerals, raws and clinkers). These materials belong to three different cement factories, which could be representative of Spanish Portland cements. This study is a follow-up of a previous research carried out by the same authors, which provides a valuable contribution to establish possible limitations of these allergenic compounds in future national as well as international standards.  相似文献   
79.
The effects of atopic dermatitis (AD) on scalp hair properties, such as morphology and water content, were investigated using atomic force microscopy (AFM) and thermogravimetric analyzer. Hairs from lesional and nonlesional scalp regions of eight patients with AD were investigated. The severity of the disease, which was evaluated using the SCORing Atopic Dermatitis index, was 48.75 (range, 40-80). Hairs from 15 normal adults were also examined as controls. The surface images were taken in an area of 20 × 20 μm(2) with 512 × 512 pixels and a scan speed of 0.8 line/s. AD affected the cuticle structures and scales of scalp hair. The edges of cuticles were torn and collapsed, and the scales were very thick. The water contents of both types of AD hair were less than the control: 12% ± 0.7%, 11.7% ± 0.4%, and 13% ± 0.8% for lesional AD hair, nonlesional AD hair, and control hair, respectively. The scalp hair of patients with AD can be characterized by thick and globular scale patterns. The hair of patients with AD has less water content than normal hair showing a good agreement with the property of skin having AD.  相似文献   
80.
特应性皮炎是一种皮肤慢性炎症性疾病,其发病机制尚不清楚,与遗传、免疫等因素相关。近年的研究发现皮肤屏障结构和功能的异常可能是特应性皮炎发病的首要机制。皮肤屏障中的关键结构和成分如角化包膜、中间丝聚合蛋白、蛋白酶及其抑制剂、脂质等的形成障碍或代谢失调,使表皮屏障功能受损,增加特应性皮炎发病的风险。编码FLG相关基因的无效突变目前被认为是特应性皮炎发病的主要因素,而角化包膜的缺陷、蛋白酶活性的增加及脂质层合成的减少加重了皮肤屏障的损害。同时临床研究表明,对皮肤屏障的修复可以降低特应性皮炎的发病率及复发率。  相似文献   
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