山西省出生缺陷高发区土壤元素分布特征

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.     

Urodynamic studies in the evaluation of young men presenting with lower urinary tract symptoms

AIM: To evaluate the usefulness of urodynamic study in young men with lower urinary tract symptoms (LUTS). METHODS: We reviewed the charts of 50 men with LUTS aged 50 years and below. Those with neurological diseases, urethral trauma or strictures were excluded. All underwent multichannel urodynamic studies (UDS). The pre- and post-UDS diagnoses and treatment modalities were compared. RESULTS: Mean age was 38.1 years (17-49). The main pre-UDS diagnoses included prostatitis in seven (14%), overactive bladder in seventeen (34%) and benign prostatic hyperplasia in nine (18%). Pre-UDS management ranged from anticholingeric agents for thirteen (26%), alpha-adrenergic antagonists for nine (18%), antibiotics for six (12%). Abnormal UDS were noted in 36 (72%), including detrusor overactivity in 9 (18%), detrusor underactivity/acontractility in 5 (10%) and bladder outlet obstruction in 21 (42%). Fourteen (28%) had primary bladder neck dysfunction and five (10%) had benign prostatic hyperplasia. Post-UDS management included anticholingeric agents for ten (26%), alpha-adrenergic antagonists for seventeen (34%), catheterization for four (10%), behavioral therapy for three (6%), surgery for three (6%). None were prescribed antibiotics. Following UDS, the diagnosis had to be updated in 40 (80%) and concomitant change in management was required in 34 (68%). CONCLUSION: Young men presenting with LUTS have different underlying etiologies. Clinical diagnosis and treatment are often empiric and inaccurate. Urodynamic study is useful in the evaluation of this group of patients as it aids in arriving at an accurate diagnosis and guides treatment therapy.     

T辅助细胞在疫苗研制中的作用

发展感染性疾病疫苗之关键挑战在于利用确定的抗原以刺激产生能引起保护作用的合适的免疫反应。肽类疫苗的运用得到了极大的关注，其意义在于，已知不同的多表位构成单一结构以诱导出所希望的免疫反应所表现出的灵活性。这一般比利用减毒的活疫苗要安全并且相对而言比制造亚单位疫苗要容易。然而，多肽疫苗的发展面临巨大挑战。这一方法在诱导遗传背景复杂的人群免疫反应方面受到限制，这与主要组织相溶性复合物(MHC)多态性有关。因同样的理由，肽类免疫应答常因缺乏适当的辅助T淋巴细胞(HIL)而引导出不充分的细胞毒素T淋巴细胞(CTL)和抗体反应。另一个运用线性肽链结构的可能缺点是：为了引导出合适抗体反应，表面免疫球蛋白受体簇对于激活静息的B细胞就成为必须因素。由WHC多肽性引起的问题可由运用不加区别的T细胞表位来解决。从麻疹病毒F蛋白(氨基酸288到302)中得到的不加区别的T细胞表位和鼠的确定结合在多种MHC分子上的辅助T细胞表位(v1EB，aa191-209)已被定性并且被用于能极大激发免疫应答的结构中，以克服单一限制型免疫应答的缺陷。合成的，非自然Pan DR表位(PADRE)具有退化的结合几种通常HLA—DR的能力，能以绝对效价和抗体反应质量两种形式来增强激发短肽链的免疫应答。另外，一些所谓的从流感病毒血凝素(HA)来的“不加区别的”T细胞表位，恶性疟疟原虫红细胞前期抗原和分枝杆菌蛋白被报道能激发广泛的免疫应答。为了不加区别地结合于几种同型和同种异型的MHCⅡ类分子，这些肽类应显示出部重叠MHC结合形式或应利用保存于配体中的固定位点和应缺失等位基因特异性固定残基，以防止结合于其它Ⅱ类分子。了解MHCⅡ类分子对肽链的不加区别及特异性识别的生物物理学基础将为在疫苗设计中突破遗传限制的策略提供分子水平的依据。     

藤茶提取物的抗炎作用研究

目的：采用几种不同类型的炎症动物模型对AGE的抗炎作用进行研究。方法：大鼠角叉菜胶性足肿胀，醋酸诱导的小鼠腹腔毛细血管通透性增高，小鼠羧甲基纤维素囊中的白细胞数目，大鼠巴豆油性气囊肿的形成。结果：连续灌胃给药5天，AGE（5、10g/kg）可以显著抑制角叉菜胶所致的大鼠足肿胀、醋酸所致的小鼠腹腔毛细血管通透性增高、小鼠羧甲基纤维素囊中白细胞的游出数目以及大鼠巴豆油性气囊的形成。结论：藤茶提取物具有显著的抗炎活性。     

Normal obstetric ultrasound reduces the risk of Down syndrome in fetuses of older mothers

The objective of this study is to determine whether a normal fetal morphology ultrasound scan in women older than 35 years reduces the risk of aneuploidy. We reviewed the results of amniocentesis and second trimester sonogram in all women older than 35 years from 1991 to 1995. None had prior screening. We excluded fetuses with structural anomalies. We determined the sensitivity and specificity of minor markers in detecting Down syndrome and also determined the reduction in risk of a normal sonogram. Among the 2060 women older than 35 years giving birth during the study period, 16 (0.78%) delivered an infant with Down syndrome. Of the 16 fetuses, two had no prenatal testing or ultrasound, two had invasive testing but no second trimester sonogram, five had a normal sonogram and seven had one or more sonographic markers of Down syndrome. At least 17% of women older than 35 years did not participate in prenatal testing or ultrasound. Ultrasound detected Down syndrome with a sensitivity of 59% (95% confidence interval: 45–72%), a false‐positive rate of 10.6% (9.4–11.8%) and a positive predictor value of 1 in 9. The likelihood of having normal karyotype if the sonogram was normal was 0.46 (0.31–0.61). In women older than 35 years, a normal second trimester sonogram reduces the risk of Down syndrome by more than 50%. At least 17% of women older than 35 years do not participate in prenatal testing or ultrasound.     

Laparoscopic cholecystectomy for left-sided gallbladder (sinistroposition).

Transposition of the gallbladder to the left side without situs inversus viscerum is rare. These gallbladders are situated under the left lobe of the liver between Segment III and IV or on Segment III to the left of the falciform ligament. Because routine preoperative studies may not detect the anomaly, it may provide the surgeons with an unusual surprise during laparoscopy. Awareness of the unpredictable confluence of the cystic duct into the common bile duct and selective use of intraoperative cholangiography aid in the safe laparoscopic management of this unusual problem.     

Does multi-vessel off-pump coronary artery bypass grafting reduce post operative morbidity compared to on-pump CABG?

Background Cardiopulmonary bypass (CPB) may contribute to the complications and it is assumed that eliminating cardiopulmonary bypass has the potential of reducing post operative morbidity after coronary artery bypass grafting (CABG). The study was carried out to compare mortality and morbidity in the off-pump and on-pump CABG groups. Methods We prospectively analysed 200 patients undergoing CABG. Group A consists of 100 patients underwent multi-vessel off-pump CABG and group B consists of 100 patients underwent CABG with CPB. The incidence of complications (mortality, re-exploration for bleeding, myocardial infarction, atrial fibrillation, neurological events, new onset renal failure (s. creatinine>1.6 mg/dL) pulmonary complications, length of ICU stay and hospital stay were recorded, analysed and compared. Results OPCAB patients received 2.73±0.61 grafts/patient and on-pump CABG patients received 3.39±0.75 grafts/patient (p value<0.00001). There was no significant statistical difference in mortality, incidence of stroke between OPCAB and CABG with CPB patients. Length of ICU stay was 32.84±4.22 vs 44.85±7.18 hrs (p value<0.00001) and hospital stay was 6.52±0.69 vs 7.94±0.92 days (p value<0.00001) between group A and group B respectively. Incidence of atrial fibrillation was less in OPCAB group 7% vs 12% although it was statistically not significant (p value 0.33). It was observed in our study that there was no significant deference in worsening of existing renal failure between on-pump CABG and OPCAB 6% vs 2% (P value 0.28). Blood utilization was significantly less in OPCAB group (p value<0.001). Conclusion There was no statistically significant difference in terms of mortality, incidence of stroke and new onset renal failure in both groups. But there was lesser incidence of post operative atrial fibrillation, worsening of existing renal failure in off-pump group though statistically not significant. There was significant reduction in blood utilization, length of ICU and hospital stay in OPCAB group.     

Localized echo-volume imaging methods for functional MRI

To perform true three-dimensional activation experiments in the human brain, dedicated localized echo-volume imaging (L-EVI) methods were developed. Three-dimensional acquisition allows generation of activation maps with minimal vascular enhancement related to inflow effects. The rapid acquisition of the L-EVI (～100 msec) reduces signal instabilities caused by motion, facilitating the detection of the small intensity changes expected with brain activation. Single-shot L-EVI was performed on normal volunteers at 1.5 T, imaging a three-dimensional predefined volume (240 × 45 × 45 mm³) in the superior portion of the brain with a spatial resolution of 3.75 × 5 × 5 mm³. Increased brain coverage was achieved with a multi-volume imaging (three-shot) version, which simultaneously achieved effective suppression of signals from cerebrospinal fluid. In addition, both asymmetric spin-echo (ASE) and spin-echo (SE) versions of the technique were used to detect blood oxygenation level dependent (BOLD) signal changes in the motor cortex with a finger-tapping paradigm. Images obtained by the L-EVI sequence were qualitatively comparable to standard multislice two-dimensional echo-planar images. Both ASE and SE functional MRI (fMRI) experiments showed consistent activation in the contralateral primary sensorimotor cortex. Furthermore, significant differences in location and magnitude of activation was observed between the two methods, confirming theoretical predictions.