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71.
Toomey  JR; Kratzer  KE; Lasky  NM; Stanton  JJ; Broze  GJ Jr 《Blood》1996,88(5):1583-1587
Tissue factor (TF) is an integral membrane glycoprotein that is believed to be the physiologic initiator of the blood coagulation cascade. Disruption of the mouse tissue factor gene leads to embryonic lethality between days E9.5-E11.5 of gestation. On E9.5, TF(-/-) embryos appear indistinguishable from their TF(+/+) and TF(+/-) littermates. By E10.5, TF(-/-) embryos are severely growth retarded, appear nearly bloodless, and are in most cases dead. Initial observations suggest that TF(-/-) embryos are dying of circulatory failure. Approximately 15% of the TF(-/-) embryos survive beyond E10.5, but none complete gestation. Heterozygotes appear normal and free of bleeding complications.  相似文献   
72.
BACKGROUND & AIMS: The aim of this study was to determine the risk of endoscopic/radiological recurrence of Crohn's disease postoperatively and the long-term outcome. METHODS: A randomized placebo-controlled trial was performed to determine the effectiveness of mesalamine in preventing recurrent Crohn's disease postoperatively. Patients in the control group were examined endoscopically/radiologically before entry into and annually during the trial. Findings were classified as minimal or severe. RESULTS: There were 76 patients (49 men and 37 women; mean age, 37.1 +/- 13.2 years). Fifty (61.7%) had terminal ileal resections. Overall, 55 endoscopic/radiological recurrences were observed in 51 patients (67.1%). Expressed actuarially, the recurrence rate was 27.5% at 1 year (95% confidence interval [CI], 15.8%-37.6%), 60.8% at 2 years (95% CI, 46%-71.3%), and 77.3% at 3 years (95% CI, 62.7%-86.3%). Nineteen (37%) were symptomatic and 12 (24%) were initially asymptomatic but later became symptomatic (mean, 13.0 +/- 8.8 months), whereas 20 (39%) remained asymptomatic (mean, 16.9 +/- 17.4 months). Patients with severe endoscopic/radiological disease were significantly more likely to be or become symptomatic than those with minimal disease (23 of 32 vs. 8 of 19, respectively; P = 0.0437). CONCLUSIONS: This study suggests that postoperative endoscopic/radiological recurrences occur later than previously reported. Furthermore, many of these patients, especially with minimal disease, will remain asymptomatic. (Gastroenterology 1997 Dec;113(6):1823-7)  相似文献   
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肝性脑病是的一种慢性消耗性的肝硬化并发症。利福昔明(rifaximin),一种口服的抗生素,治疗急性肝性脑病的疗效已有报道,但其预防此病疗效未知。  相似文献   
75.
Albert NM, Gillinov AM, Lytle BW, Feng J, Cwynar R, Blackstone EH. A randomized trial of massage therapy after heart surgery. Heart Lung 2009; 38: 480–90.  相似文献   
76.
PURPOSE OF REVIEW: This review article will discuss aortic stenosis, the evolving studies defining the cellular mechanisms and the potential for medical therapies for the treatment of this disease. RECENT FINDINGS: Currently, the only therapy for these patients is surgical valve replacement. In the past decade there has been a change in the paradigm towards our understanding of the cellular biology of this disease process. Studies in laboratories across the world have demonstrated that this disease has an active biology and that this biology may be targeted with medical therapies similar to that of vascular atherosclerosis. SUMMARY: Calcific aortic stenosis is the third most common form of cardiovascular disease in the USA. It has replaced rheumatic heart disease in prevalence in western countries due to improved access to healthcare and the widespread use of antibiotics.  相似文献   
77.
78.

Background

Mathematical modelling and analysis is now accepted in the engineering design on par with experimental approaches. Computer simulations enable one to perform several 'what-if' analyses cost effectively. High speed computers and low cost of memory has helped in simulating large-scale models in a relatively shorter time frame. The possibility of extending numerical modelling in the area of breast cancer detection in conjunction with medical thermography is considered in this work.

Methods

Thermography enables one to see the temperature pattern and look for abnormality. In a thermogram there is no radiation risk as it only captures the infrared radiation from the skin and is totally painless. But, a thermogram is only a test of physiology, whereas a mammogram is a test of anatomy. It is hoped that a thermogram along with numerical modelling will serve as an adjunct tool. Presently mammogram is the 'gold-standard' in breast cancer detection. But the interpretation of a mammogram is largely dependent on the radiologist. Therefore, a thermogram that looks into the physiological changes in combination with numerical simulation performing 'what-if' analysis could act as an adjunct tool to mammography.

Results

The proposed framework suggested that it could reduce the occurrence of false-negative/positive cases.

Conclusion

A numerical bioheat model of a female breast is developed and simulated. The results are compared with experimental results. The possibility of this method as an early detection tool is discussed.
  相似文献   
79.
80.
Throughout the western United States, studies have identified various detrimental effects of contaminants to aquatic biota from the use of agricultural drainage water for management of arid wetlands. However, little is known about the relative contributions of contaminant loading from pollutants dissolved in water compared with those carried by drifting material (e.g., detritus) associated with drainage water. Consequently, we determined loading rates for contaminants dissolved in water and those incorporated by drifting material for drainage (Diagonal Drain) as well as fresh (S-Line Canal) water used for wetland management at Stillwater National Wildlife Refuge (SNWR), Nevada during the early, middle, and late periods of the irrigation season (June through mid-November) in 1993. We found loading rates for trace elements throughout the irrigation season were almost entirely (> 98%) associated with contaminants dissolved in the water rather than incorporated by drift. Although drift contributed little to the total loading for trace elements to SNWR wetlands, contaminant concentrations were much greater in drift compared with those dissolved in water. Loading rates for dissolved As, B, Hg, and total dissolved solids (TDS) differed among periods for the Diagonal Drain. Along the Diagonal Drain, loading rates for dissolved As, B, Hg, Mo, unionized ammonia (NH3-N), TDS, and Zn differed among its three sampling sites. B was the only trace element with differences in loading rates for drift among periods from the Diagonal Drain. In contrast, loading rates for As, B, Cr, Cu, Hg, Se, and Zn in drift differed among periods for the S-Line Canal. Along Diagonal Drain, loading rates in drift for B (middle and late periods), Cr, Cu, and Zn differed among sites. Hg (xˉ ≥ 12.0 ng/L) and NH3-N (xˉ ≥ 0.985 mg/L) dissolved in water as well as B (xˉ ≥ 97.4 μg/g DW) and Hg (xˉ ≥ 0.461 μg/g DW) in drift from the Diagonal Drain and S-Line Canal exceeded screening levels (SLs) for protection of aquatic biota throughout the irrigation season. Dissolved As (xˉ ≥ 0.0426 mg/L) in water from the Diagonal Drain during all periods exceeded the SL for protection of aquatic biota. Dissolved B (xˉ = 1.03 mg/L) in water from the Diagonal Drain during the early period exceeded the SL for protection of aquatic biota. Received: 18 September 1997/Accepted: 5 February 1998  相似文献   
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