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71.
目的研究选择性头部降温对缺血性脑损伤胎羊纹状体神经元凋亡和星形胶质细胞增殖的影响。方法胎羊于妊娠117~124d时通过双侧颈动脉阻塞30min造成双侧脑缺血损伤,损伤后将胎羊随机分为:损伤组(n=10)、2h低温组(损伤后2h开始亚低温治疗,n=7)和6h低温组(损伤后6h开始亚低温治疗,n=8),另设正常对照组(n=5)。通过冷循环水进行选择性头部降温,取脑组织用免疫组化法检测胎羊纹状体caspase-3(半胱天冬氨酸酶-3),GFAP(胶质纤维酸性蛋白)和PCNA(增殖细胞核抗原)的表达。结果①纹状体神经元凋亡:正常对照组中,caspase-3表达极少(11.00±13.77),损伤组caspase-3免疫阳性细胞为177.70±48.69,明显增加(P=0.000),损伤后2h治疗组(54.14±39.44,P=0.000)和损伤后6h治疗组(122.43±52.36,P=0.017)均能减少caspase-3免疫阳性细胞。②纹状体星形胶质细胞增殖:与正常对照组(163.40±21.98)相比,缺血性脑损伤组的GFAP免疫阳性细胞明显增多(433.25±66.69,P=0.000),损伤后2h开始亚低温治疗(219.50±35.31,P=0.000)和损伤后6h开始亚低温治疗(272.50±86.20,P=0.000)均能减少GFAP免疫阳性细胞。③纹状体PCNA阳性细胞的表达:在正常对照组中,PCNA免疫阳性细胞较少,为153.40±12.46,缺血性脑损伤组的PCNA免疫阳性细胞明显增多(353.70±45.60,P=0.000),损伤后2h开始亚低温治疗(187.14±26.26,P=0.000)和损伤后6h开始亚低温治疗(230.25±67.46,P=0.000)均能减少PCNA免疫阳性细胞。结论亚低温可以抑制纹状体神经元的凋亡和星形胶质细胞的增殖,该作用可能为选择性头部降温的脑保护作用机制之一。 相似文献
72.
73.
After the introduction of the colposcope for the examination of children suspected of being sexually abused in Leeds, a study was undertaken to describe the findings in detail. A total of 109 consecutive prepubertal girls, mean age 70.4 months were assessed including colposcopic genital and anal examination, and peer group review of reports and photographs. Fifty nine children had signs consistent with blunt force penetrating trauma (hymenal transection/major notch, scar, or hymenal attenuation). Transections were encountered most commonly at 6 o'clock (directly posterior). In 46 the hymenal orifice was gaping with thigh abduction only and in 47 the hymenal orifice transverse diameter was greater than 4 mm on labial separation. Overall, physical findings were commonly present and in only two cases were no signs recorded. Non-specific and frequent findings included patterns of labial and introital reddening. Supportive hymenal signs including swelling, rounding of edge, thickening, distortion, and loss of symmetry were common. Labial fusion was present in 20. Urethral dilatation with labial separation was noted in 14. Physical findings including normality are consistent with abuse and even minor anogenital signs as well as negative findings should be documented. Colposcopy and photography are valuable tools in peer review, teaching, and case management. 相似文献
74.
AJ Blethyn HR Jenkins R Roberts K Verrier Jones 《Archives of disease in childhood》1995,73(6):534-535
Little objective evidence has been published to support the claim that constipation is an important contributory factor in recurrent urinary tract infection (UTI) in childhood. Using a radiological scoring system, two observers assessed faecal loading from abdominal radiographs of children with proved UTIs. There was a significant increase in the degree of faecal loading in children with UTI when compared with controls (r = 0.237). This difference was mainly accounted for by girls with recurrent (greater than five) UTIs. This study confirms an association between recurrent UTI and faecal loading. Further studies are needed to establish if there is a causal relationship and benefits from treatment. 相似文献
75.
Soberón-Mobarak A Díaz-Aparicio E Torres-Armenta J Adams LG Suárez-Güemes F 《Vaccine》2000,18(26):3018-3020
The objective of this study was to determine if B. abortus rough mutant strains RB51 and rfbK are eliminated in goat milk. Thirty milk goats were divided into two groups. Group I was inoculated with 4x10(10) cfu/ml of B.abortus RB51 strain and Group II with 1x10(9) cfu/ml of B. abortus rfbK strain by subcutaneous route in the right axilary region. Milk samples were taken aseptically on a daily basis for the first 30 days and weekly for the second and third months. The samples were inoculated on Farrell's media and incubated under 5-10% CO(2) at 37 degrees C for 10 days. The suspicious colonies were recultured in Farrell's media. There were no isolations of bacteria with characteristics of Brucella from any of the milk samples collected during 90 days of the study. It was concluded that neither of the strains used at these doses were eliminated by milk in goats inoculated during lactation. 相似文献
76.
Geller AC Zhang Z Sober AJ Halpern AC Weinstock MA Daniels S Miller DR Demierre MF Brooks DR Gilchrest BA 《Journal of the American Academy of Dermatology》2003,48(1):34-41
BACKGROUND: In response to the precipitous increase of melanoma, the American Academy of Dermatology (AAD) has coupled melanoma/skin cancer education with free skin cancer screening programs throughout the United States since 1985. The purpose of this analysis is to investigate the risk factors, access to dermatologic services, and screening results of participants in AAD-sponsored programs during the first 15 years that this service was available to the US public. METHODS: Before screening, participants completed a standardized AAD screening form. Screening forms were counted in the AAD central office and recorded in annual summaries. Forms were sent for keypunching and returned to the AAD on a computer disk annually. In 1999, disks were sent to Boston University and a master file was created. RESULTS: Computerized records were available for 819,019 screening forms and 639,835 individuals. In all, 65% of screenees had at least 1 risk factor and 33% had at least 2 risk factors. Of screenees, 33% reported a changing mole and 37% had skin type I or II. Among all screenees, nearly 80% did not have a regular dermatologist, 78% reported no prior AAD skin cancer screening, 60% had never had their skin checked by any doctor, and 51% would not have seen a doctor for skin cancer without the free screening. Nearly 30% of screenees had a presumptive diagnosis of skin cancer or a precursor lesion. Melanomas confirmed by postscreening biopsy were more likely than those in population-based registries to be less than 1.50 mm in thickness. CONCLUSIONS: AAD national screening and educational programs have expanded to all 50 states, provided educational messages about sun protection and early detection to millions, and served many US citizens with an above average risk for skin cancer and suboptimal access to dermatologic care. Screenees had a disturbingly high point prevalence of malignant and premalignant skin lesions. Sustained commitment by the AAD leadership and membership to the screening program is critical to reducing the morbidity and mortality of skin cancer. 相似文献
77.
Juergen C Dinger Lothar AJ Heinemann Sabine Möhner Do Minh Thai Anita Assmann 《BMC women's health》2006,6(1):13-13
Background
Previous epidemiological studies have inconsistently shown a modestly increased breast cancer risk associated with hormone replacement therapy (HRT). Limited information is available about different formulations - particularly concerning different progestins. 相似文献78.
Background
The Licensing Act 2003 (The Act) was implemented on the 24th November 2005 across England and Wales. The Act allowed more flexible and longer opening hours for licensed premises. We investigated the effect of The Act on alcohol related attendances to an inner city emergency department in Birmingham, UK. 相似文献79.
Extralobar pulmonary sequestration was found in a newborn premature infait that presented with non-immune hydrops fetalis, massive bilateral hydrothorax and polyhydramnios in utero. The baby died of severe respiratory insufficiency 15 h after birth. Postmortem examination revealed distended lymphatic vessels in the sequestered lung tissue probably due to impeded lymph drainage. We suggest that not extralobar pulmonary sequestration itself but a subsequent massive unilateral hydrothorax due to severe obstruction of lymph drainage was the cause of the non-immune hydrops fetalis, pulmonary hypoplasia and polyhydramnios. If these symptoms are diagnosed before delivery, a search for extralobar pulmonary sequestration is indicated. 相似文献
80.