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121.
RD Hull GE Raskob RF Brant GF Pineo KA Valentine 《Canadian Metallurgical Quarterly》1997,157(22):2562-2568
BACKGROUND: Randomized trials have demonstrated the importance of achieving adequate heparinization early in the course of therapy. Recently, some authors reported a pooled analysis of selected studies in the literature that suggested that there is no convincing evidence that the risk of recurrent venous thromboembolism is critically dependent on achieving a therapeutic activated partial thromboplastin time result at 24 to 48 hours. METHODS: We provide the analyses of patient groups entered into our series of 3 consecutive double-blind randomized trials evaluating initial heparin therapy for proximal deep venous thrombosis. RESULTS: Logistic regression analysis of the patient groups receiving the less intense initial intravenous heparin dose of 30,000 U/24 h demonstrated that subtherapy for 24 hours predicted the onset of venous thromboembolic events. Failure to achieve a therapeutic activated partial thromboplastin time by 24 hours was associated with a 23.3% frequency of venous thromboembolism vs 4% to 6% for those whose activated partial thromboplastin time exceeded the therapeutic threshold by 24 hours (P=.02). Time-to-event analysis shows the increased frequency of recurrent venous thromboembolic events during the period of study in patients who were subtherapeutic for 24 hours compared with those who were therapeutic (P=.001). CONCLUSIONS: Our findings reaffirm the clinical importance of rapidly achieving therapeutic levels of heparin. Patients who failed to achieve the therapeutic threshold by 24 hours were at an increased risk of subsequent recurrent venous thromboembolism. These findings are independently supported by the results of a randomized trial comparing different intensities of initial heparin treatment by continuous infusion. 相似文献
122.
OBJECTIVE: To determine the value of operation in patients with bowel obstruction caused by recurrent abdominal cancer. DESIGN: Retrospective case review. SETTING: The University of Connecticut Health Center, Farmington. PATIENTS: Ninety-eight patients admitted with a diagnosis of bowel obstruction and malignant neoplasm between November 1, 1987, and June 30, 1995. RESULTS: Data for 75 patients who developed a bowel obstruction within 5 years of a malignant diagnosis were analyzed. Forty-six patients (61%) were treated operatively and 29 (39%) were treated nonoperatively. The operative group included 32 patients (70%) whose obstruction was caused by carcinomatosis; 6 (19%) of these 32 patients had had at least 1 episode of previous obstruction requiring hospitalization. They had a 22% in-hospital mortality, stayed an average of 21 days in the hospital, and survived 7 +/- 6 months (mean +/- SD) after discharge; 5 (16%) had at least 1 episode of postoperative obstruction that required hospitalization. After discharge from the hospital, 53% had an excellent or good quality of life (assessed retrospectively). Of the 29 patients in the nonoperative group, 16 (55%) had carcinomatosis. These 16 patients had a 38% in-hospital mortality (6 of 16), stayed an average of 10 days in the hospital, and survived a mean of 13 +/- 9 months; 3 (19%) had at least 1 episode of recurrent obstruction requiring hospitalization. After discharge from the hospital, 6 (37%) had an excellent or good quality of life. CONCLUSION: The value of operative intervention for bowel obstruction in patients with cancer is derived from the possibility of a benign cause, not alleviation of the consequences of carcinomatosis. 相似文献
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Low-frequency (1/f) noise in near-fully-depleted Thin-Film Silicon-On-Insulator (TFSOI) CMOS transistors designed for sub-l-V applications is investigated in the subthreshold region, linear region, and saturation region of operation for the first time. The noise in these surface-channel devices is composed of a bias invariant 1/f component and a bias dependent generation-recombination (G/R) component that becomes enhanced in the subthreshold region of operation for both n- and p-channel MOSFETs. Results presented in this letter are consistent with the noise being dominated by a number fluctuation model. These results demonstrate that the bias independent 1/f noise spectrum of the n-channel TFSOI MOSFET is comparable to the 1/f noise level found in conventional bulk silicon submicron CMOS fabrication processes 相似文献
127.
This study examined the attitudes toward breastfeeding of medical professionals working with pregnant or new mothers. Most advocated breastfeeding to mothers who had not made an infant feeding decision; fewer talked about breastfeeding during the first trimester; and many recommended that mothers supplement a breastfed infant with prepared commercial baby milk. All agreed that a mother's return to work led to early discontinuance of breastfeeding and that the family is a major influence on a mother's decision to breastfeed. To increase the prevalence of breastfeeding, the study group recommended prenatal education, participation in support groups, and promotion of breastfeeding through the media. 相似文献
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Lin Y. Jordan G.A. Sanford M.O. Zhu J. Babcock W.H. 《Power Systems, IEEE Transactions on》2006,21(4):1520-1527
With the issue of its Notice of Proposed Rulemaking on Standard Market Design (SMD NOPR) in July 2002, the U.S. Federal Energy Regulatory Commission (FERC) took a major step to ensure consistency in wholesale electricity markets. The SMD NOPR contains the Commission's most definitive guidelines regarding its vision of future competitive wholesale electric markets, their structure, and scope. Regional transmission organizations (RTOs) are at the heart of the order-providing the structure and institutions to support wholesale electricity trade and the management of the nation's transmission grid. Locational marginal pricing (LMP) and congestion revenue rights (CRRs) will be used to manage the operation of the transmission grid. As the geographics of these RTOs will expand across many states and one or more independent system operators (ISOs), the state regulators and ISOs, affected by FERC orders, are particularly interested in the assessment of economic impact in their states and ISO market areas, if these orders were adopted. While one can easily conceptualize the steps required to characterize the economic impact of implementing RTOs and SMD, the modeling and analytical methodology is extremely complex and requires that numerous "reasonable assumptions" be made to approximate the operations of the electric system. Results from a case study are used to illustrate the impact of key assumptions and the inherent imprecision in this type of analysis. These types of issues, modeling, and analytical considerations are relevant for evaluating the impact of changing electricity market structures throughout the world 相似文献
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