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71.
目的:探讨超声导航系统在引导经皮肾穿刺过程中的有效性及安全性.方法:选择2013年5月至10月北京大学人民医院泌尿外科,采用超声导航系统引导经皮肾穿刺行经皮肾镜取石术病例16例,对建立每处皮肾通道的穿刺次数、每次穿刺时长、回吸出尿液的颜色、手术出血量、术后并发症等进行回顾性分析.结果:16例患者建立皮肾通道18处,全部一次穿刺成功,穿刺时长15 ~ 54 s,平均(26.90±11.37)s,术后血红蛋白水平较术前下降1.41% ~24.06%,平均(9.56±5.27)%,术后出现发热2例,未见其他并发症发生.结论:超声导航系统在引导经皮肾穿刺过程中操作简单、快速、准确,成功率高,有效地降低了穿刺的难度,是一项安全、有效的新技术.  相似文献   
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《Hospital practice (1995)》2013,41(1):232-235
Abstract

A coronary artery chronic total occlusion (CTO) represents a coronary artery that has been occluded for a long period of time, typically months. Coronary artery CTOs are common and occur in approximately one-third of patients referred for coronary angiography. Revascularization of CTO is technically challenging and has historically been associated with lower procedural success rates and higher complication rates. Technical success of CTO revascularization has significantly improved given remarkable advances in interventional cardiology over the past 3 decades. However, the decision to perform CTO revascularization remains a dilemma, given the lack of robust clinical evidence to support its use.  相似文献   
75.
An experimental and theoretical methodology is proposed to calculate the permeability of microcapsules that contain a core of oil-based active ingredient. Theoretical analysis is performed considering the polydispersity of the measurable capsule size, which allows the estimation of the permeability polydispersity via three different methods. The models proposed were applied in order to determine the permeability of melamine-formaldehyde microcapsules with hexyl salicylate as core oil. Release experiments were performed with four different co-solvents (ethanol, propan-1-ol, propan-2-ol and 1,3-butanediol) of different concentration. Permeability values were found to be constant, despite a two order magnitude of difference in the solubility concentrations.  相似文献   
76.
Protein concentration and hydrostatic pressure were measured in subcutaneous tissue of rats during development of aminonucleoside nephrosis. Samples of interstitial fluid for protein analysis were collected from subcutaneous tissue by a wick method, and hydrostatic pressure was measured by a modified Scholander technique. When the serum protein concentration was reduced from 6.1 to 4.8 g/100 ml, interstitial fluid protein concentration fell from 3.0 to 1.1 g/100 ml. This corresponds to a reduction of calculated oncotic pressures from 18.0 to 13.0 mm Hg and from 7.8 to 3.0 mm Hg in serum and interstitial fluid, respectively, thus leaving a nearly constant net transcapillary oncotic pressure. When serum protein concentration was further reduced to 3.8 g/100 ml, interstitial fluid protein concentration was reduced to 0.5 g/100 ml, reducing net transcapillary oncotic pressure by 2–3 mm Hg. The average hydrostatic pressure in subcutis was 1.0 mm Hg sub-atmospheric under control conditions and did not change during hypoproteinemia. The results indicate that a reduction of interstitial protein concentration is an important factor in preventing edema formation in hypoproteinemia.  相似文献   
77.
Purpose. To review the complications and recovery of patients with Achilles tendon rupture managed by percutaneous repair, open repair, and non-operative means in a tertiary referral centre between 2001 and 2003.

Methods. The operating theatre register and logbooks of the Consultants were used to identify surgically managed patients, while plaster room records were used for conservatively managed patients. We collated demographic and management details.

Results. The number of plaster changes (p < 0.001), median length of time in cast (p < 0.001), and number of outpatient visits (p < 0.05) was greater in conservatively managed patients. We performed no formal statistical analysis given the small numbers. Conservative management was the least expensive and open surgery the most costly modality of management. Percutaneous surgery was approximately a third of the cost of open surgery when performed under local anaesthetic.

Conclusion. In our setting, percutaneous repair and conservative management are viable alternatives to open surgery, which carries higher complications rates and was the most costly of the three. Individual patients will have different needs due to their age, occupation, or level of sporting activity.  相似文献   
78.
Percutaneous coronary intervention (PCI) to the unprotected left main stem offers an attractive alternative to bypass grafting, but is associated with a significant clinical risk and therefore demands special consideration. Successful left main PCI is dependent upon the morphology of the lesion and the technical quality of the procedure. For these reasons, intravascular ultrasound (IVUS) has been the most popular adjunct to coronary angiography during left main PCI. However, trials of IVUS in left main PCI have produced inconclusive results, and most data predate the use of drug-eluting stents. Despite this, IVUS offers practical benefits in both case selection, and in guiding angioplasty and stenting. Here, we review the arguments for the present and future role of IVUS in left main PCI.  相似文献   
79.
The present view focuses on the possibility that cationic antimicrobial peptides (CAMPs) might, in addition to their killing effects due to permeabilization of microbial membranes, also function similarly to β-lactam antibiotics to activate nascent autolytic wall enzymes, leading to bacteriolysis. Since the massive release of microbial cell wall components is a major cause of postinfectious sequelae, the in vivo process of bacteriolysis must be controlled. Due to the emergence of antibiotic resistance in pathogenic bacteria, CAMPs might be useful as an alternative to antibiotics. However, they should be used with caution, since they might also function as a ‘double-edged sword’ by injuring both the bacteria and host.  相似文献   
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