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11.
Histological characterization of a delayed wound healing model in pig   总被引:1,自引:0,他引:1  
Chronic wounds, such as venous ulcers and pressure ulcers, frequently remain unresponsive to currently available treatments. Several animal models of wound healing have been published, including models of impaired healing developed to mimic the clinical condition of chronic wounds better. We used a delayed wound healing model in the pig that uses irradiation of the skin prior to creation of the surgical wounds and characterized it histologically. Radiation was used on one side of the back prior to making four full-thickness wounds on each side. Clinical observations were performed to record granulation tissue, reepithelialization, and wound area as a function of time. Histology data were obtained at 1, 2, 3, and 4 weeks, and slides were stained with hematoxylin and eosin for general observations. Immunohistochemistry was performed using laminin as a marker for blood vessels, and the number, size, and circularity of blood vessels found in the granulation tissue were measured. Our results show that this model causes a delay in wound healing that is mostly apparent between days 7 and 15. Granulation tissue took more time to form and fill the wounds on the irradiated side, and blood vessels were slower to develop. Blood vessels were larger and more irregular in shape on the irradiated side than on the control side. After 2 weeks, healing resumed, indicating that the induced damage was not irreversible. These results suggest that this model can be used to test the effects of therapeutic approaches intended to treat chronic wounds.  相似文献   
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Background and aims In contrast to that in patients with primary hyperparathyroidism, the value of intraoperative intact parathyroid hormone (iPTH) measurement is still unclear in patients with renal hyperparathyroidism and was, therefore, evaluated in a large cohort of patients.Patients Intraoperative iPTH measurement was performed in 153 patients with renal hyperparathyroidism (129 with terminal renal failure and 24 with functioning kidney graft). Subtotal and total parathyroidectomy were performed in 123 and 13 patients, respectively, during initial surgery. In patients with recurrent disease (17), the respective hyperfunctioning tissue was removed. Intraoperative blood samples were obtained by puncture of the internal jugular vein before preparation of the parathyroids (PTH0) and 15 min after parathyroidectomy (PTH15). iPTH was measured with the Elecsys 2010 system. Postoperative iPTH levels (PTHpost) were determined at postoperative days 1 to 3 and at week 2. Patients were arbitrarily divided in four groups according to the postoperative iPTH values: 0–25 pg/ml (group 1), 26–65 pg/ml (group 2), 66–150 pg/ml (group 3) and more than 150 pg/ml (group 4).Results The mean PTH0 value was 869±57 pg/ml, which decreased to 167±15 pg/ml at PTH15. The mean relative PTH15 value was 21.6±1.7%. Postoperatively, iPTH decreased to 42±9 pg/ml. The postoperative iPTH value of the 129 patients with terminal renal failure was 25 pg/ml or less in 99 patients, 26–65 pg/ml in 11 patients, 66–150 pg/ml in eight patients and higher than 150 pg/ml in 11 patients. Two successive criteria of iPTH decrease were used: first, a PTH15 of 150 pg/ml or, second, a relative PTH15 of 30% less was used. Fifteen patients did not fulfil both criteria. In 13 of them (86.7%) iPTHpost was higher than 65 pg (true failure to decline). Of 114 patients who fulfilled the criteria, 108 (94.7%) had normal postoperative iPTH values (true decline). Absolute PTH15 values of less than 150 pg/ml predicted normal postoperative iPTH levels in 77 of 78 patients.Conclusion A PTH15 value of 150 pg/ml or less predicts operative success in patients with renal failure in 98.7% of cases, independently of the relative decay. In contrast, if the relative PTH15 is higher than 30%, high postoperative PTH values are predicted with a probability of 86.7%. Although there remain some borderline cases, intraoperative iPTH measurement is accurate and also can be useful in patients with renal hyperparathyroidism.The paper was presented at the first constitutive meeting of the European Society of Endocrine Surgeons (ESES) in Pisa, Italy, on 14–15 May 2004  相似文献   
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Abstract:  The purpose of this study was to assess the predictive value of smoking history on breast cancer diagnosis in a referral clinic population. We conducted a case–control study using clinical data collected on 8,097 female patients (1,225 breast cancer cases and 6,872 controls) seen in the Mayo Clinic Breast Clinic between August 1, 1993 and November 31, 2003. Breast cancer patients and noncancer patients significantly differed with respect to age at time of the index visit (p < 0.001), number of pregnancies (p = 0.006), number of live births (p = 0.002), vital status at last known follow-up (p < 0.001), current menstruation (p < 0.001), age at menopause (p < 0.001), history of hysterectomy (p < 0.001), use of oral contraception (p = 0.05), duration of oral contraception use (p = 0.001), use of other exogenous hormones (p < 0.001), duration of exogenous hormone use (p = 0.05), breast pain at time of index visit (p = 0.002), smoking status (p < 0.001), and use of five or more alcoholic beverages per week (p = 0.002). After adjustment for these baseline characteristics, having a personal history of smoking was found to be predictive of breast cancer diagnosis (odds ratios [OR] = 1.25, p = 0.004). Other positive predictors for breast cancer diagnosis were: age (OR = 1.02, p < 0.001), history of hysterectomy (OR = 0.66, p < 0.001), prior use of oral contraception for more than 11 years (OR = 2.10, p < 0.001), and prior use of other exogenous hormones/estrogen (OR = 1.81, p < 0.001). In this referral practice having a personal history of smoking is predictive of breast cancer diagnosis. Further studies are needed to further explore this relationship.  相似文献   
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Liver transplantation (OLT) for end-stage chronic hepatitis-B-virus (HBV) infection is frequently complicated by HBV recurrence. In the present study we investigated whether human leucocyte antigen (HLA)-matching influences the outcome after OLT. In a retrospective analysis we reviewed 84 recipients of liver transplants for end-stage HBV-cirrhosis and complete HLA-typing for outcome after OLT. Follow-up ranges from 1 to 110 months (median = 55.6 months). Immunosuppression consisted of Cyclosporin A (CsA)-based quadruple induction therapy or Tacrolimus-based induction protocols. Immunoprophylaxis with hepatitis B immunoglobulin was started at OLT and continued long-term. Actuarial 1- and 5-yr graft survival figures were 90.5 and 80.4%, respectively. Hepatitis-B recurrence was responsible for 15 of 20 (75%) graft failures. We observed a significantly improved graft survival in patients with more HLA-A, -B compatibilities (p = 0.02), whereas the degree of HLA-DR compatibilities did not influence the outcome. The occurrence of HBV-reinfection was significantly lower in HLA-A, -B matched grafts (p < 0.05). Additionally, graft survival was prolonged in patients with HBV-reinfection and 1 or 2 HLA-B compatibilities when compared with patients with HBV-reinfection and a complete HLA-B mismatch (p = 0.02). In conclusion, this retrospective analysis shows that more HLA-A, -B compatibilities seems to be associated with an improved graft survival in patients after OLT for end-stage HBV infection.  相似文献   
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A forty-six-year-old man presented with a two-month history of increasing neck pain of insidious onset. He received treatment from his familty doctor and chiropractor consisting of analgesics and manipulation respectively, both of which did not offer relief. The patient presented to University Hospital where plain radiographs and CT showed a pathological fracture of the C4 vertebral body. A neoplasm was suspected and surgical excision revealed a giant-cell tumour of bone. This type of neoplasm is rare in the spine and difficult to manage in this site. This case highlights some of the problems encountered in the treatment of giant-cell tumour of the spine.  相似文献   
17.

Background  

Human immunodeficiency virus infected individuals are prone to malnutrition due to increased energy requirements, enteropathy and increased catabolism. Trace elements such as zinc and selenium have major role in maintaining a healthy immune system. This study was designed to evaluate the nutritional status of Iranian subjects who were newly diagnosed with human immunodeficiency virus infection and to compare serum level of zinc and selenium in these patients with those of the sex and aged match healthy subjects.  相似文献   
18.
背景目前已开展了对重性精神病患者进提供连续性服务的研究。目的探讨基层对有抑郁症风险患者提供连续性服务的水平,并与对心力衰竭患者的服务水平进行对比。方法采用抑郁症风险患者与心力衰竭患者对比的探索性研究。采用患者问卷评估服务的持续性,包含如下内容:(1)联系的服务提供者数(个人连续性);(2)诊所内服务提供者之间的合作(团队连续性)(6个项目,分数1~5分);(3)诊所外全科医师与服务提供者之间的合作(跨界连续性)(4个项目,分数1~5分)。结果大多数抑郁症风险患者在过去1年中寻遍整个服务提供界联系了几个服务提供者,曾遇到过高水平团队连续性服务及低水平跨界连续性服务。在诊所中可接触到的不同服务提供者要明显多于心力衰竭患者服务提供者(P<0.01)。抑郁症风险患者的服务提供者之间的合作更好一些,每项平均得分4.3分,心力衰竭患者得分为4.0分(P=0.03)。然而,跨界连续性服务方面正好相反:抑郁症风险患者每项平均得分3.5分,心力衰竭患者得分为4.0分(P=0.01)。结论抑郁症风险患者与心力衰竭患者之间的探索性对比显示:体验服务连续性方面的差距不大。对此还应行进一步分析。  相似文献   
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