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81.
Patients with influenza infection most commonly present with upper and occasionally lower respiratory tract symptoms. However, extrapulmonary presentations such as hepatitis are infrequently observed. We report a case of a hemodialysis patient with influenza A infection who presented with severe hepatitis and liver failure, while his respiratory symptoms were mild. It is important to recognize influenza infection as an unexplained cause of hepatitis and liver failure. In our case, liver failure resolved with supportive treatment.  相似文献   
82.
通过介绍楔形桩的受力机理 ,指出楔形桩不同于一般桩基 ,其楔形构造改变了桩周土的天然结构状态 ,利于发挥桩土的共同作用 ,提高了其承载力。介绍并总结了现有楔形桩承载力计算公式及按其计算所出现偏差的原因。并分析了楔形桩承载力与几何尺寸的一般关系  相似文献   
83.

Background and aims

Because their lungs and immune system are not completely developed, children are more susceptible to respiratory disease and more vulnerable to ambient pollution. We assessed the relation between prenatal and postnatal nitrogen dioxide (NO2) levels and the development of lower respiratory tract infections (LRTI), wheezing and persistent cough during the first year of life.

Methods

The study population consisted of 352 children from a birth cohort in Valencia, Spain. Prenatal exposure to NO2, a marker of traffic related air pollution was measured at 93 sampling sites spread over the study area during four different sampling periods of 7 days each. It was modeled for each residential address through land use regression using the empirical measurements and data from geographic information systems. Postnatal exposure was measured once inside and outside each home using passive samplers for a period of 14 days. Outcomes studied were any episode of LRTI during the child's first year of life diagnosed by a doctor (bronchitis, bronchiolitis or pneumonia), wheezing (defined as whistling sounds coming from the chest), and persistent cough (more than three consecutive weeks). Outcomes and potential confounders were obtained from structured questionnaires. Multiple logistic regression was used to identify associations.

Results

The cumulative incidence (CI) at first year of life was 30.4% for LRTI (23.0% bronchiolitis, 11.9% bronchitis and 1.4% pneumonia), 26.1% for wheezing and 6.3% for persistent cough. The adjusted odds ratio (95% confidence interval) per 10 μg/m3 increment in postnatal outdoor NO2 concentration was 1.40 (1.02-1.92) for persistent cough. We also found some pattern of association with LRTI, bronchiolitis, bronchitis, wheezing and persistent cough in different prenatal periods, although it was not statistically significant.

Conclusions

Our results indicate that exposure to outdoor, but not indoor, NO2 during the first year of life increases the risk of persistent cough.  相似文献   
84.
Reducing indoor exposure to influenza particles can be an important strategy to manage residential infections. Many portable air cleaning (PAC) technologies are currently employed in residential environments but very little research has been performed to evaluate and compare their performance in terms of particle removal associated with influenza. This study evaluates the effectiveness of portable air cleaners at removing airborne NaCl particles as an analogue to the influenza virus and applies the results to an IAQ mass balance model to evaluate the performance in controlling residential exposures and mitigating infection risks. Various devices representing different PAC technologies were tested using a pull down particle challenge in a full scale stainless steel chamber. Particle generation and measurement were conducted using a 6-jet atomizer and a paired aerodynamic particle sizer (APS)-scanning mobility particle sizer (SMPS), respectively. PAC incorporating HEPA filtration, electrostatic precipitation, ion generation and electret filtration were tested. We found that particle exposures released during a cough or sneeze event in a typical Quebec City residential room in Canada can significantly be reduced using HEPA, electrostatic precipitation and electret filtration PACs when compared with a situation where no PAC is being used. Modelling analysis demonstrates that the use of these PACs can mitigate the risks of influenza infection via airborne route for a caregiver or a spouse sharing the same room. The implications of this study are significant considering low ventilation rates of Quebec City residences.  相似文献   
85.
PurposeOcular hypotony after trabeculectomy may be treated medically, surgically and with a tamponade. Three cases are reported in which a scleral lens was applied to treat ocular hypotony after mitomycin C (MMC) augmented trabeculectomy.MethodsIn this retrospective case series the records of three eyes of three patients who developed ocular hypotony after they had undergone trabeculectomy augmented with MMC were evaluated. The patients were between 11 and 69 years of age and the intraocular pressure (IOP) after surgery ranged between 3 and 6 mmHg. All three patients showed a negative Seidel test; one had suspected hypotonic maculopathy and one had a collapsed anterior chamber. After unsuccessful treatment with large bandage lenses all three patients were subsequently fitted with a scleral lens. The scleral lens was fitted to fully cover and compress the bleb. Scleral lenses were worn continuously with a check-up after one night of wear and subsequent check-ups when needed. One patient continued to wear the scleral lens for a further 6.5 months on a daily wear basis.ResultsIn all three eyes the IOP was higher after wearing the scleral lens. Two patients stopped wearing the scleral lens after the IOP was stable. One patient developed a cataract; the cataract surgery was combined with a bleb revision and scleral lens wear was therefore discontinued.DiscussionThe scleral lens might be a useful tool in the treatment of ocular hypotony after trabeculectomy augmented MMC surgery. The effect of the scleral lens on the ocular pressure is unpredictable. Caution is advised in vulnerable corneas due to risk factors such as hypoxia and infection. Further research is warranted to establish the safety of the procedure, the patient selection and the overall success in a larger patient group.  相似文献   
86.
外照射急性放射病的主要致死原因之一是严重感染,预防和控制感染是救治急性放射病的关键。本文从外照射急性放射病合并感染的防治方面介绍其发病机制、临床表现、预防和救治措施以及其预后转归的研究现状。  相似文献   
87.
采动影响区煤层动态含气量数值模拟   总被引:2,自引:1,他引:1  
煤矿采动影响区是地面煤层气开发或井下瓦斯抽放的有利部位。基于矿井瓦斯工作实践,划分了煤矿采动影响区类型,阐述了采动影响区煤层动态含气量的数值模拟方法,并以阳煤集团二矿为例对采动影响区内煤层动态含气量进行了估算。  相似文献   
88.
计算机病毒的计算复杂度问题   总被引:1,自引:0,他引:1  
计算机病毒对计算机系统及软件造成各种各样的损害,除了一些常见的损害,例如删除数据或程序、修改系统信息以外,它们还造成一些非破坏性的影响,例如消耗大量的存贮及时间。这个问题涉及到计算机病毒的计算复杂度。文章初步探讨计算机病毒的计算复杂度问题,从数学上证明两个基本结论:存在计算机病毒,它的传染过程具有任意大计算复杂度;存在计算机病毒,被感染程序的执行过程具有任意大的计算复杂度。除此而外,文章简要讨论计算机病毒检测过程的计算复杂度问题。  相似文献   
89.
核医学影像检查对炎症疾病的诊断有独特的价值,标记抗生素是近来新开发的一类炎症显像剂。本文用Tc标记了左旋氧氟沙星(LVFX),研究其生物分布和动物模型的显像结果。使用酒石酸亚锡作为还原剂,快速标记LVFX。研究了^99Tc^m-LVFX在炎症动物模型内的生物分布和炎症动物模型注射^99Tc^m-LVFX后的显像结果。结果表明标记方法简单迅速,标记物稳定。生物分布和显像结果均表明^99Tc^m-LVFX在炎症组织内有较高的摄取。研究提示^99Tc^m-LVFX是一种潜在的炎症显像剂。  相似文献   
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