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2.
利用三角函数幂公式、L′Hospital法则、分部积分公式,得到含有三角函数的第一类广义积分integral from n=0 to ∞(((sin(θ_x))/x)~ndx)的计算公式,其中n≥1且θ≠0.  相似文献   
3.
医院药品采购供应及药库管理   总被引:1,自引:0,他引:1  
对医院药品采购供应及药库管理提出了一些看法。  相似文献   
4.
Prediction of bacteria-carrying particle (BCP) dispersion and particle distribution released from staff members in an operating room (OR) is very important for creating and sustaining a safe indoor environment. Postoperative wound infections cause significant morbidity and mortality, and contribute to increased hospitalization time. Increasing the number of personnel within the OR disrupts the ventilation airflow pattern and causes enhanced contamination risk in the area of an open wound. Whether the amount of staff within the OR influences the BCP distribution in the surgical zone has rarely been investigated. This study was conducted to explore the influence of the number of personnel in the OR on the airflow field and the BCP distribution. This was performed by applying a numerical calculation to map the airflow field and Lagrangian particle tracking (LPT) for the BCP phase. The results are reported both for active sampling and passive monitoring approaches. Not surprisingly, a growing trend in the BCP concentration (cfu/m3) was observed as the amount of staff in the OR increased. Passive sampling shows unpredictable results due to the sedimentation rate, especially for small particles (5–10 μm). Risk factors for surgical site infections (SSIs) must be well understood to develop more effective prevention programs.  相似文献   
5.
对于一类00型或∞0型未定式,给出其极限为1的一个充分条件,并通过实例展示其应用。  相似文献   
6.
Prediction of bacteria-carrying particle (BCP) dispersion and particle distribution released from staffmem- bers in an operating room (OR) is very important for creating and sustaining a safe indoor environment. Postoperative wound infections cause significant morbidity and mortality, and contribute to increased hospitalization time. Increasing the number of personnel within the OR disrupts the ventilation airflow pattern and causes enhanced contamination risk in the area of an open wound. Whether the amount of staffwithin the OR influences the BCP distribution in the surgical zone has rarely been investigated. This study was conducted to explore the influence of the number of personnel in the OR on the airflow field and the BCP distribution. This was performed by applying a numerical calculation to map the airflow field and Lagrangian particle tracking (LPT) for the BCP phase. The results are reported both for active sampling and passive monitoring approaches. Not surprisingly, a growing trend in the BCP concentration (cfu/ms) was observed as the amount of staff in the OR increased. Passive sampling shows unpredictable results due to the sedimentation rate, especially for small particles (5-10 i~m). Risk factors for surgical site infections (SSls) must be well understood to develop more effective prevention programs.  相似文献   
7.
介绍利用导数建立等价无穷小关系的三个方法,并举例说明.  相似文献   
8.
给出了从Stolz定理到L′Hospital法则的推导过程及各定理之间的联系.  相似文献   
9.
 The Netherlands Institute for Accreditation of Hospitals (NIAZ) was established at the end of 1998. It was founded by the PACE foundation, the Society of University Hospitals, the Netherlands Association of General Hospitals and the Society of Medical Specialists in the Netherlands. Since then in the Netherlands 19 pilot accreditations have been performed based upon 35 NIAZ-PACE standards for hospital departments and functions, and the overall standard 'quality system'. The aims and methods of the accreditation system were inspired by examples from the other side of the Atlantic, especially from Canada. The characteristics are: voluntary-based, self-evaluation, peer-review and aiming at continuous improvement of quality of care. Received: 15 April 2000 · Accepted: 15 April 2000  相似文献   
10.
The Staudinger ketene-imine cycloaddition reactions of cyclobrassinin phytoalexin analogues 2-aryl-4,9-dihydro-1,3-thiazino[6,5-b]indoles with chloroacetyl chloride as a ketene source were investigated under different conditions. Both β-lactam ring formation and the N-chloroacetylation of the indole moiety took place. The indole N-chloroacetyl group can be easily removed by treatment in the presence of silica gel in methanol at reflux temperature. The selective β-lactam formation can be also achieved in certain cases under milder Staudinger conditions. The treatment of azeto[2,1-b]thiazino[6,5-b]indole-1-one derivatives with sodium ethoxide in ethanol provided the novel thiazepino[7,6-b]indole ring systems in a one-step ring transformation. The structures of the new ring systems were determined by means of IR and NMR spectroscopy.  相似文献   
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