颈内动脉接近完全闭塞时的处理

目的由于卒中风险随着狭窄严重程度的增加而升高，因此认为颈内动脉（ICA）接近闭塞患者的卒中风险很高。在现有的随机试验中，还没有专门针对这种情况进行探讨，因此其处理尚存在争汶。方法：对相关文献进行系统评价。结果：对ICA接近闭塞患者的处理还存在争议：一些学者支持进行干预，而另一些学者则认为存在风险或没有益处而反对进行干预。在ICA接近闭塞的有症状患者中进行一项比较外科治疗与最佳内科治疗的多中心前瞻性随机试验似乎非常困难，因为这类研究需要大量的患者。尽管如此，基于目前的证据，似乎很难拒绝手术治疗。结论：由于目前对ICA接近闭塞患者的最佳处理方案仍存在着争议，因此需要前瞻性观察性研究以证实其在有症状和无症状人群中的患病率以及相关的卒中风险。基于目前的证据，大多数医疗中心选择手术治疗，但它相对干内科治疗的特粱尚右待证章．     

An optimal three-stage design for phase II clinical trials

A phase II clinical trial in cancer therapeutics is usually a single-arm study to determine whether an experimental treatment (E) holds sufficient promise to warrant further testing. When the criterion of treatment efficacy is a binary endpoint (response/no response) with probability of response p, we propose a three-stage optimal design for testing H₀: p ≤ p₀ versus H₁: p ≥ p₁, where p₁ and p₀ are response rates such that E does or does not merit further testing at given levels of statistical significance (α) and power (1 ? β). The proposed design is essentially a combination of earlier proposals by Gehan and Simon. The design stops with rejection of H₁ at stage 1 when there is an initial moderately long run of consecutive treatment failures; otherwise there is continuation to stage 2 and (possibly) stage 3 which have decision rules analogous to those in stages 1 and 2 of Simon's design. Thus, rejection of H₁ is possible at any stage, but acceptance only at the final stage. The design is optimal in the sense that expected sample size is minimized when p = p₀, subject to the practical constraint that the minimum stage 1 sample size is at least 5. The proposed design has greatest utility when the true response rate of E is small, it is desirable to stop early if there is a moderately long run of early treatment failures, and it is practical to implement a three-stage design. Compared to Simon's optimal two-stage design, the optimal three-stage design has the following features: stage 1 is the same size or smaller and has the possibility of stopping earlier when 0 successes are observed; the expected sample size under the null hypothesis is smaller; stages 1 and 2 generally have more patients than stage 1 of the two-stage design, but a higher probability of early termination under H₀; and the total sample size and criteria for rejection of H₁ at stage 3 are similar to the corresponding values at the end of stage 2 in the two-stage optimal design.     

Changes in Escherichia coli resistance to co-trimoxazole in tuberculosis patients and in relation to co-trimoxazole prophylaxis in Thyolo,Malawi

In Thyolo district, Malawi, an operational research study is being conducted on the efficacy and feasibility of co-trimoxazole prophylaxis in preventing deaths in HIV-positive patients with tuberculosis (TB). A series of cross-sectional studies were carried out to determine i) whether faecal Escherichia coli (E.coli) resistance to co-trimoxazole in TB patients changed with time and ii) whether the resistance pattern was different in HIV positive TB patients who were taking co-trimoxazole prophylaxis. Co-trimoxazole resistance among E.coli isolates in TB patients at the time of registration was 60% in 1999 and 77% in 2001 (p<0.01). Resistance was 89% among HIV-infected TB patients (receiving co-trimoxazole), while in HIV negative patients (receiving anti-TB therapy alone) it was 62% (p<0.001). The study shows a significant increase of E.coli resistance to co-trimoxazole in TB patients which is particularly prominent in HIV infected patients on co-trimoxazole prophylaxis. Since a high degree of plasmid-mediated transfer of resistance exists between E.coli and the Salmonella species, these findings could herald limitations on the short and long term benefits to be anticipated from the use of co-trimoxazole prophylaxis in preventing non-typhoidal salmonella bacteraemia and enteritis in HIV infected TB patients in Malawi.     

Intrapartum Care of a Woman With Aortic Aneurysms

Advances in technology and complex care have enabled women with various health problems to become and remain pregnant. Consequently, health-care practitioners are seeing an increasing number of pregnant women who have aortic aneurysms. This case study describes the culturally sensitive intrapartum care of a Middle Eastern woman with ascending and descending aortic aneurysms.     

创伤病人的手术与焦虑状态调查

采用状态——特质焦虑问卷及１０项躯体性焦虑测试题，对４０例外科创伤病人手术前后的焦虑状态调查显示：术前状态焦虑量表评分显著高于术后；术前躯体性焦虑评分显著高于术后；高特质焦虑评分亚组与低特质焦虑评分亚组术前状态焦虑评分无显著差异，但术后则前者显著高于后者；急诊手术者手术前后状态焦虑评分显著高于择期手术者。