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81.
目的研究低剂量电离辐射对小鼠免疫系统影响的剂量率效应。方法以^60Co-γ射线为辐照源,低、中和高3个辐射剂量(0.075、0.5、2.0Gy),恒定剂量率(0.5mGy/min)全身一次性照射小鼠,ELISA检测照射4h后血浆IL-12和IL-10的含量。结果低、中剂量照射后,血浆中IL-12、IL-10和IL-12/IL-10出现程度几乎相同地下降;但高剂量照射后,IL-12进一步显著下降,而IL-10上升至对照组水平,IL-12/IL-10比值进一步下降。结论恒定0.5mGy/min剂量率的^60Co-γ射线照射可损伤机体免疫功能,在0.075~0.5Gy剂量范围内损伤轻微,在2.0Gy时损伤明显,表明低剂量率电离辐射对免疫系统具有损伤作用。  相似文献   
82.
The phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, has been reported to produce sustained pulmonary vasodilatation in patients with pulmonary hypertension (PH). Recently, vardenafil, a more potent and selective PDE-5 inhibitor than sildenafil, has been approved for the treatment of erectile dysfunction. However, the long-term effects of oral vardenafil in patients with PH are unknown. We studied five consecutive patients with PH; one with primary pulmonary hypertension, two with chronic pulmonary thromboembolism, one with Eisenmenger syndrome (ventricular septal defect) and one with secondary pulmonary hypertension after a ventricular septal defect closure operation. In an acute hemodynamic trial, vardenafil (5 mg) significantly decreased both the pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR) with an increase in cardiac output. In a chronic hemodynamic trial, the maintenance dose of vardenafil (10 to 15 mg) for 3 months significantly decreased the PVR, but not the SVR, with a 20.7% reduction of the PVR/ SVR ratio. Plasma brain natriuretic peptide (BNP) levels were also significantly decreased after 3 months. This pilot study demonstrates that long-term oral vardenafil therapy may be a safe and effective treatment for patients with PH.  相似文献   
83.
BACKGROUND: Ankle brachial index(ABI)is widely involved in researches and clinical application of peripheral vascular injury of patients with diabetes (DM);however ,the application in cerebral infarction(CI)is rare.OBJECTIVE: To investigate the possible risk factor of cerebral infarction plus peripheral arterial disease(PAD),compare metabolic characteristics of patients who having CI plus PAD or only having CI,and understand the significance of ABI on screening and diagnosing CI plus PAD of lower limb.DESIGN: Contrast observation based on CI patients.SETTING: Deparment of Neurology,Nanxishan Hospital of Guangxi Zhang Autonomous Region.PARTICIPANTS:A total of 124 CI patients were selected from Department of Neurology.Nanxishan Hospital of Guangxi Zhuang Autonomous Region from July 2005 to April 2006,including 72 males and 52 females aged from 45 to 88 years.All patients met the diagnostic criteria of cerebrovascular disease established by National Academic Conference of Cerebrovascular Diseases in 1995 and determined as cerebral infarction with MRI or CT examination.All patients provided informed consent.There were 46 cases(37.2%)with CI plus PAD and 78 cases(62.8%)only with CI.METHODS: Blood pressure of bilateral ankles and upper extremities was measured at plain clinostatism with DINAMAP blood pressure monitor(GE Company).The ratio between average systolic pressure of lateral ankle and average systolic pressure of both upper extremities was regarded as ABI.The normal ABI was equal to or more than 0.9.If ABI<0.9 occurred at one side,patients were diagnosed as PAD.On the second morning after hospitalization,blood was collected to measure fasting blood glucose(FBG),2-hour postprandial blood glucose(PBG2h),glycosylated hemoglobin(HbAlc),triglycerides(TG),total cholesterol(TC),high-density lipoprotein cholesterol(HDL-C)and low-density lipoprotein cholesterol(LDL-C).Among them,blood glucose.lipid and other biochemical markers were measured with enzyme chemistry assay and HbA1c was measured with HbA1c meter based on high liquid phase.Measurement data and enumeration data were compared with t test and Chi-square test.and multiple factors were deat with Logistic regression analysis and multivariate linear regression analysis.MAIN OUTCOME MEASURES: Results of correlation between ABI and metabolic markers with multivariate linear regression analysis;risk factors of CI plus PAD with Logistic regression analysis;comparisons of metabolic markers between PAD and non-PAD patients.RESULTS:All 124 patients with acute CI were involved in the final analysis.①Comparisons of metabolic markers:Levels of serum LDL-C and uric acid(UA)were higher of PAD patients than those of non-PAD patients(t=2.051 9,3.339 1,P<0.05);however,there were no significant differences among other metabolic markers(P>0.05).②Results of multivariate linear regression analysis:PBG2h,LDL.C and UA were obvious correlation with ABI of posterior tibial artery of lower limb and dorsal pedis artery rpartial regression coefficient:-0.231 to-1.010,P<0.05).③Risk factors of CI plus PAD with Logistic regression analysis:Age.Smoking history,sum of CI focus(≥3)and LDL-C were independent risk factor of CI plus PAD(OR=1.524-5.422,P<0.05-0.01 ).CONCLUSION:①Levels of serum LDL-C and UA of patients with CI plus PAD are high.②ABI of lower limbs is correlation with PBG2h,LDL-C and UA.In addition,measuring ABI is beneficial for early diagnosing PAD of lower limbs of patients who have poorly controlled blood glucose,abnormal lipid and poor renal function.③Age,LDL-C and sum of CI focus(≥3)are independent risk factors of CI plus PAD.It is of significance for screening non-PAD patients to evaluate risk degrees and prognosis and select therapeutic methods based on ABI measurement.  相似文献   
84.
超声在狭窄颈部动脉支架植入术后随访中的应用   总被引:2,自引:0,他引:2  
目的评价超声在颈部动脉(颈动脉、锁骨下动脉及椎动脉)狭窄血管支架成形术后随访中的应用价值。方法应用超声随访观察47例患者的15枚颈内动脉(ICA)支架、9枚锁骨下动脉(SCA)支架及26枚椎动脉(VA)支架术后1~12个月,观察狭窄血管处支架位置、支架内及远端的收缩期峰值流速(PSV)、支架内有无血栓及再狭窄等情况,判断其疗效。结果支架置入术后超声示狭窄ICA、VA及SCA内径较术前明显增宽,内径分别由术前(2.90±0.76)mm、(2.0±0.38)mm及(4.00±1.46)mm增宽至术后的(4.20±1.78)mm、(3.4±0.51)mm、(6.15±0.98)mm;PSV分别由术前(115±15)cm/s、(181.4±32.5)cm/s、(257.67±66.41)cm/s减低至术后的(75±24)cm/s、(47.15±12.44)cm/s及(98.87±48.63)cm/s。随访中发现2例患者颈内动脉支架狭窄,1例颈内动脉支架闭塞。结论超声是评价颈部动脉狭窄血管支架成形术后疗效的无创、安全可靠的影像学检查方法。  相似文献   
85.
目的比较劳累性心绞痛患者抑郁障碍与冠状动脉粥样硬化程度的相关性,以进一步明确两者之间关系。方法将146名劳累性心绞痛患者根据汉密尔顿抑郁量表评分分为无抑郁症状组、可疑抑郁症状组、明确抑郁症状组。比较三组冠脉Gensini积分。结果3组之间Germini积分值存在统计学差异(P〈0.05)。HAMD量表评分与Gensimi评分成正相关(r=0.244,P〈0.01)。结论劳累性心绞痛患者冠脉粥样硬化程度与抑郁障碍程度成正相关,抑郁障碍对冠脉粥样硬化的发展可产生不良影响。  相似文献   
86.
目的 探讨肺上沟癌的临床特点及放疗疗效和不良反应。方法 回顾性分析 3 3例肺上沟癌住院病人的临床特征和常规放疗的疗效。结果 肺上沟癌占原发性支气管肺癌的 2 9% ,常见症状为 :患侧肩、背和上肢疼痛 ( 78 8% ) ,后 1,2 ,3肋骨或椎骨破坏( 5 7 6% ) ,Horner’s综合征 ( 3 6 7% ) ;少见的症状为 :咳嗽 ( 2 7% ) ,咯血 ( 9% ) ;中位生存期为 8 4月 ;1,3 ,5年生存率分别为 3 5 6% ,12 3 % ,4 6% ;放疗反应可耐受。结论 肺上沟癌相当少见 ,其临床特征基本符合pancoast综合症 ,本病预后差 ,但放疗可缓解疼痛 ,提高生存质量。  相似文献   
87.
Angiotensin II receptor blockers (ARBs) are widely used for the treatment of hypertension. It is believed that treatment with an ARB increases the level of plasma angiotensin II (Ang II) because of a lack of negative feedback on renin activity. However, Ichikawa (Hypertens Res 2001; 24: 641-646) reported that long-term treatment of hypertensive patients with olmesartan resulted in a reduction in plasma Ang II level, though the mechanism was not determined. It has been reported that angiotensin 1-7 (Ang-(1-7)) potentiates the effect of bradykinin and acts as an angiotensin-converting enzyme (ACE) inhibitor. It is known that ACE2, which was discovered as a novel ACE-related carboxypeptidase in 2000, hydrolyzes Ang I to Ang-(1-9) and also Ang II to Ang-(1-7). It has recently been reported that olmesartan increases plasma Ang-(1-7) through an increase in ACE2 expression in rats with myocardial infarction. We hypothesized that over-expression of ACE2 may be related to a reduction in Ang II level and the cardioprotective effect of olmesartan. Administration of 0.5 mg/kg/day of olmesartan for 4 weeks to 12-week-old stroke-prone spontaneously hypertensive rats (SHRSP) significantly reduced blood pressure and left ventricular weight compared to those in SHRSP given a vehicle. Co-administration of olmesartan and (D-Ala7)-Ang-(1-7), a selective Ang-(1-7) antagonist, partially inhibited the effect of olmesartan on blood pressure and left ventricular weight. Interestingly, co-administration of (D-Ala7)-Ang-(1-7) with olmesartan significantly increased the plasma Ang II level (453.2+/-113.8 pg/ml) compared to olmesartan alone (144.9+/-27.0 pg/ml, p<0.05). Moreover, olmesartan significantly increased the cardiac ACE2 expression level compared to that in Wistar Kyoto rats and SHRSP treated with a vehicle. Olmesartan significantly improved cardiovascular remodeling and cardiac nitrite/ nitrate content, but co-administration of olmesartan and (D-Ala7)-Ang-(1-7) partially reversed this anti-remodeling effect and the increase in nitrite/nitrate. These findings suggest that olmesartan may exhibit an ACE inhibitory action in addition to an Ang II receptor blocking action, prevent an increase in Ang II level, and protect cardiovascular remodeling through an increase in cardiac nitric oxide production and endogenous Ang-(1-7) via over-expression of ACE2.  相似文献   
88.
颈肩背轴型反流皮瓣修复儿童颏颈瘢痕挛缩   总被引:2,自引:1,他引:1  
目的探讨修复儿童颏颈瘢痕挛缩一种实用而较理想的方法.方法以颈横动脉浅支为蒂,利用其与旋肩胛动脉皮支的丰富吻合,反流形成超长的轴型皮瓣,向前旋转修复瘢痕松解后的颈前创面.结果采用本皮瓣修复30例儿童颏颈瘢痕挛缩,其中18例随访2年,颈部活动自如,颌骨发育无明显异常,皮瓣色泽良好,效果令人满意.结论本皮瓣轴型血管恒定,反流灌注动脉压高有保证,供瓣面积充足,供区多可直接拉拢缝合,是修复儿童颏颈瘢痕挛缩的较理想方法.  相似文献   
89.
骨髓间充质干细胞分化为皮肤附属器细胞的初步实验研究   总被引:4,自引:0,他引:4  
目的探讨骨髓间充质干细胞(marrowmesenchymalstemcells,MSCs)分化为创面皮肤附属器细胞的可能性,及其参与创面修复的可能机制。方法无菌条件下取Wistar大鼠股骨骨髓细胞,密度梯度离心分离、纯化MSCs,体外培养扩增后,用BrdU标记细胞。另于同种雄性Wistar大鼠背部正中,制备1cm×1cm全厚皮肤缺损创面模型,将BrdU标记的1×106/mlMSCs从阴茎静脉输注,术后第3天与第7天切取创面组织,行BrdU免疫组织化学单染色,以及BrdU和广谱角蛋白免疫组织化学双染色。结果BrdU阳性细胞出现在创面皮下组织、皮脂腺、毛囊和骨髓腔中。免疫组织化学双染色结果显示,皮脂腺和毛囊有BrdU阳性细胞,同时表达广谱角蛋白。结论创面愈合过程中,MSCs归巢并参与创面修复;在实验性全身皮肤缺损创面微环境下,MSCs可分化为皮肤附属器细胞。  相似文献   
90.
山西省出生缺陷高发区土壤元素分布特征   总被引:6,自引:0,他引:6  
目的 了解出生缺陷高发区土壤中元素分布特征,为出生缺陷的干预和治疗提供理论依据.方法 于2005年1-5月,选择山西省吕梁山区出生缺陷高发的中阳县和交口县作为出生缺陷高发区,以人口相对集中的河道两侧为采样点,共涉及8个乡镇,79个行政村;选择晋中盆地出生缺陷低发的祁县作为出生缺陷对照区,采样点均匀分布,共涉及6个乡镇,27个行政村.采集距耕地表层10~20cm深的土壤,共采集样品131件.采用ICP-电感耦合等离子发射光谱法,对土壤样品中的16种元素进行测定.结果 高发区土壤中元素总量明显高于低发区.与祁县相比,交口县土壤中元素含量偏高的有As、Mo、Pb、Ni、V,含量偏低的元素有Se,差异均有统计学意义(P<0.05);中阳县土壤中含量偏高的元素为Sn、Se、Mo、Zn、Sr、Pb、Ni、Fe、V、Ca、Cu、Al,偏低的元素为Mg和Na,差异均有统计学意义(P<0.05).土壤中元素含量(μg/g)与出生缺陷发病率的(1/万)逐步回归分析显示,交口县土壤中Mo、Al、As、Ni、Pb、Zn元素对病情影响有统计学意义(均P<0.01),其标准的逐步回归判别方程为:y=-1.321 1.106 Mo-0.509 Al 0.117 As 0.663 Ni-0.429 Pb-0.262 Zn(R2a=0.891);中阳县土壤中Pb、Mg、Ca、Al、Zn元素对病情影响有统计学意义(均P<0.05),其标准回归方程为:y=-1.757 0.441 Pb-0.264Mg 0.309 Ca-0.186Al 0.162Zn (R2a2=0.839).结论 交口县和中阳县土壤中Pb、Mo、Al等含量异常可能是两县出生缺陷高发的原因之一.  相似文献   
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