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21.
Increased calcium uptake in vascular tissue, leading to elevated cytosolic free calcium has been implicated in the pathophysiology of hypertension. This study examined the effect of oral heparin on systolic blood pressure, platelet cytosolic free calcium and aortic calcium uptake in spontaneously hypertensive and normotensive Wistar-Kyoto rats. Starting at age 12 weeks, each strain of rats were divided into 2 groups (6 animals in each group); the control group was placed on H2O (100%) and the experimental group was placed on H2O with heparin (0.5 mg sodium heparin/ml H2O) for a period of nine weeks. At 21 weeks, systolic blood pressure, platelet cytosolic free calcium and aortic calcium uptake were significantly higher in spontaneously hypertensive rats on water compared with spontaneously hypertensive rats on heparin and Wistar-Kyoto rats on water and on heparin. Oral heparin treatment normalized the elevated platelet cytosolic free calcium, aortic calcium uptake and systolic blood pressure in spontaneously hypertensive rats but had no effect on Wistar-Kyoto rats. Heparin also prevented onset of adverse renal vascular changes observed in spontaneously hypertensive rats. Oral heparin treatment did not cause abnormal hematological, biochemical or pathological changes in rats.  相似文献   
22.

Background

The intracerebral hemorrhage (ICH) score is a simple grading scale that can be used to stratify risk of 30 day mortality in ICH patients. A similar risk stratification scale for subarachnoid hemorrhage (SAH) is lacking. We sought to develop a risk stratification mortality score for SAH.

Methods

With approval from the Institutional Review Board, we retrospectively reviewed 400 consecutive SAH patients admitted to our institution from August 1, 2006 to March 1, 2011. The SAH score was developed from a multivariable logistic regression model which was validated with bootstrap method. A separate cohort of 302 SAH patients was used for evaluation of the score.

Results

Among 400 patients with SAH, the mean age was 56.9 ± 13.9 years (range, 21.5–96.2). Among the 366 patients with known causes of SAH, 292 (79.8 %) of patients had aneurysmal SAH, 65 (17.8 %) were angiogram negative, and 9 (2 %) were other vascular causes. The overall in-hospital mortality rate was 20 %. In multivariable analysis, the variables independently associated with the in-hospital mortality were Hunt and Hess score (HH) (p < 0.0001), age (p < 0.0001), intraventricular hemorrhage (IVH) (p = 0.049), and re-bleed (p = 0.01). The SAH score (0–8) was made by adding the following points: HH (HH1-3 = 0, HH4 = 1, HH5 = 4), age (<60 = 0, 60–80 = 1, ≥80 = 2), IVH (no = 0, yes = 1), and re-bleed within 24 h (no = 0, yes = 1). Using our model, the in-hospital mortality rates for patients with score of 0, 1, 2, 3, 4, 5, 6, and 7 were 0.9, 4.5, 9.1, 34.5, 52.9, 60, 82.1, and 83.3 % respectively. Validation analysis indicates good predictive performance of this model.

Conclusion

The SAH score allows a practical method of risk stratification of the in-hospital mortality. The in-hospital mortality increases with increasing SAH mortality score. Further investigation is warranted to validate these findings.  相似文献   
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Impaired gastrointestinal motility as a result of interruption of sympathetic outflow is a common occurrence in the spinal cord injury (SCI) population. In addition, frequent use of medications with anticholinergic properties in this population results in further impairment of peristalsis resulting in gastrointestinal stasis. Since SCI patients often lack sensation below the level of injury, they may present with vague symptoms, which complicates the diagnosis of intestinal obstruction. We report the first case of gastric phytobezoar in a patient with T4 ASIA A paraplegia who presented with vague upper abdominal discomfort, anorexia, weight loss, and vomiting. Because mortality rates can be as high as 30% if phytobezoars remain untreated, gastrointestinal phytobezoars should be considered in the differential diagnosis of abdominal discomfort in SCI patients. Etiologic factors for phytobezoars are discussed for the general population and in particular, for patients with SCI.  相似文献   
29.
Management of a floating sternum after repair of pectus excavatum   总被引:7,自引:0,他引:7  
PURPOSE: The aim of this study was to examine the authors' experience with patients who have floating sternum after correction of pectus excavatum via the classical Ravitch procedure. A floating sternum is defined as a sternum in which the only attachment to the chest wall is its superior (cranial) border, and in which the body is secured only by the manubrium and whatever lateral and inferior fibrous bands are present. Typically, a floating sternum is caused by either extensive resection of the costal cartilages and perichondrium during correction of pectus excavatum or failure of proper regrowth of these cartilages. METHODS: The authors retrospectively assessed the charts of all patients diagnosed with a floating sternum noting age at original correction of pectus excavatum, time from original correction of pectus excavatum to diagnosis of floating sternum, age at correction of floating sternum, complaints before stabilization of the sternum, methods of repair, and postoperative complications. RESULTS: Between July 1993 and June 1999, floating sternum was diagnosed in 7 patients. The mean age of patients who underwent operative correction of a floating sternum was 28.9 years (range, 16 to 42 years). The mean time interval between original correction of pectus excavatum, or "redo," and diagnosis of a floating sternum was 9.9 years (range, 2 to 20 years). Complaints before correction of the floating sternum included sternal pain and instability, exercise intolerance, and difficulty breathing. Operative repair consisted of mobilizing the lateral and inferior edges of the sternum, detaching the fibrous perichondrium, performing anterior sternal osteotomies, and finally supporting the sternum with substernal Adkins struts. All 7 patients had successful stabilization of the sternum. Two of 7 patients underwent 2 procedures to successfully stabilize the sternum. One patient has Adkins struts still in place because of hematopoetic malignancy. Six of 7 patients are now without symptoms. CONCLUSIONS: A floating sternum is a morbid phenomenon that may manifest many years after the original procedure. It can cause significant sternal pain, chest wall instability, and respiratory dysfunction, which are the hallmark indications for correction. Repair of a floating sternum can be accomplished successfully.  相似文献   
30.
Sclerosing encapsulating peritonitis, or “abdominal cocoon,” is a rare but serious complication of continuous ambulatory peritoneal dialysis. It is characterized by the diffuse appearance of marked sclerotic thickening of the peritoneal membrane resulting in intestinal obstruction.A 14-year-old adolescent boy with a history of end-stage renal failure on continuous ambulatory peritoneal dialysis presented with symptoms of acute intestinal obstruction. A computed tomography scan of the abdomen revealed distended small bowel loops clustered and displaced to the right upper quadrant. The overlying peritoneum was markedly thickened and calcified. Laparotomy confirmed the diagnosis of sclerosing encapsulating peritonitis and the patient was treated with excision of the fibrocollagenous membrane. Postoperatively, he had prolonged ileus requiring parenteral nutritional support and peritoneal dialysis was restarted on postoperative day 10.A high degree of cognizance is needed to facilitate diagnosis and treatment of this uncommon and potentially life-threatening condition.  相似文献   
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