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1.
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   
2.
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.  相似文献   
3.
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。  相似文献   
4.
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.  相似文献   
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7.
The effect of H1 and H2 receptor-blocking agents on antibody-dependent cell-mediated cytotoxicity (ADCC) was studied. The H1 receptor-blocker clemastinum and the H2 receptor blocker cimetidine dose-dependently inhibited the antibody-dependent cytotoxic activity of normal human peripheral blood mononuclear cells on chicken erythrocytes. The inhibition cannot be explained either by a direct toxic effect on effector cells or by blocking of Fc receptors. The possible involvement of histamine receptor-bearing effector cells in human ADCC is suggested.  相似文献   
8.
Mouse antibodies were prepared to human amniotic fluid fibronectin by means of somatic cell hybrids. Comparison of immunological reactivity of antibodies with amniotic and plasma fibronectin revealed that the two molecules had very similar patterns of antigenic determinants. Antibodies from one cell population, however, bound belier to amniotic fluid fibronectin, indicating that there is a difference in the molecular structure of fibronectins isolated from the two sources.  相似文献   
9.
The human promyelocytic leukemia cell line HL60 can be differentiated to mature granulocytes upon exposure to DMSO (1.3%, 6 days). The ability of these cells to metabolize arachidonic acid via the 5-lipoxygenase pathway to form 5-HETE, LTB4, and 5,12-diHETEs, has been previously documented. However, the production of peptidoleukotrienes by DMSO-differentiated HL60 cells has not been previously reported. Arachidonic acid metabolites produced via 5-lipoxygenase were identified by reverse-phase, high-performance liquid chromatography, immunoreactivity specific for peptidoleukotriene, glutamyl transpeptidase transformation, characteristic UV spectra, and GC mass spectra. Leukotriene synthesis in the DMSO-differentiated HL60 cell is maximal at 5 min when stimulated with the calcium ioniphore, A23187 (1M), in the presence of calcium. These cells produce 12.94±1.8 ng/106 cells of LTC4 and 3.8±0.4 ng/106 cells of LTB4. LTC4 and LTB4 are also synthesized in the undifferentiated cell when stimulated with 1M A23187 and 1 mM Ca2+, but in much smaller quantities, i.e., 1.91±0.42 ng/106 cells of LTC4 and 0.41 ng±0.06/106 cells of LTB4. The synthetic chemotactic peptide, f-Met-Leu-Phe, also elicits formation of LTC4 and LTB4 in a dose-dependent manner in the presence of exogenously added calcium. Maximal stimulation of DMSO-differentiated cells with f-Met-Leu-Phe produces 2.5±0.2 ng of LTC4 and 1.45±0.2 ng of LTB4 per 106 cells. The observation that DMSO-differentiated HL60 cells produce LTC4, as well as other 5-lipoxygenase products, increases the utility of this cell line for unraveling the regulation of leukotriene biosynthesis by granulocytes.  相似文献   
10.
During a 6-month period, 95 invasive infections due to Streptococcus pyogenes and group C or group G Streptococcus dysgalactiae subsp. equisimilis were recorded from 40 centers of 16 cities in Argentina. We describe here epidemiologic data available for 55 and 19 patients, respectively, associated with invasive infections due to S. pyogenes and S. dysgalactiae subsp. equisimilis. The associated isolates and 58 additional pharyngeal isolates were genotyped and subjected to serologic and/or antibiotic susceptibility testing. Group A streptococcal emm type distribution and strain association with toxic shock appeared to differ somewhat from results found within the United States; however, serologic characterization and sof sequence typing suggested that emm types found in both countries are reflective of shared clonal types.  相似文献   
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