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71.
72.
Gaylen L. Edwards B. Douglas White Bin He Roger G. Dean Roy J. Martin 《Brain research》1997,755(1):84-90
Lesions centered on the area postrema (AP) and adjacent nucleus of the solitary tract (AP/mNTS-lesions) are reported to result in increased consumption of highly palatable diets. Recent studies suggest that neuropeptide Y (NPY) may cause a preference for carbohydrate-rich diets. Thus, it is possible that NPY may play a role in the enhanced intake of highly palatable diets by AP/mNTS-lesioned rats. In the studies reported here, we found that lesions centered on the AP result in increased levels of NPY-immunoreactivity in the paraventricular nucleus of the hypothalamus. Additionally, steady-state NPY mRNA in the basomedial hypothalamus including the arcuate nucleus was elevated. Enhanced NPY was not found throughout the hypothalamus however, as NPY-immunoreactivity was not elevated in the lateral hypothalamus or the tissue bordering the anteroventral third ventricle. These data suggest the possibility that elevated hypothalamic NPY, particularly in the arcuate and paraventricular nuclei, may contribute to the altered food intake and energy balance observed in rats with lesions centered on the AP. 相似文献
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Patterns of calcifications and cholangiographic findings in hepatobiliary tuberculosis 总被引:3,自引:0,他引:3
Dean D. T. Maglinte M.D. Sol Z. Alvarez Anastacio C. Ng Jose L. Lapeña 《Abdominal imaging》1988,13(1):331-335
The radiologic findings on conventional examinations (plain films and cholangiograms) in a large group of patients with proven hepatobiliary tuberculosis are reviewed. The plain film findings of large chalky and confluent hepatic calcifications or nodal-type calcifications along the course of the common bile duct are suggestive of hepatobiliary tuberculosis. Small, discrete, scattered calcifications may be mimicked by histoplasmosis but can be differentiated from hepatobiliary tuberculosis. Obstructing defects seen on cholangiography are indicative of tuberculosis when adjacent calcifications are present. The patterns of liver calcifications could provide a clue to the diagnosis of hepatobiliary tuberculosis and its differentiation from liver calcifications of various other etiologies. 相似文献
76.
Cytogenetic effects of methylmercury in embryos of the killifish,Fundulus heteroclitus 总被引:1,自引:0,他引:1
Dean M. Perry Judith S. Weis Peddrick Weis 《Archives of environmental contamination and toxicology》1988,17(5):569-574
Fertilized eggs of the killifish,Fundulus heteroclitus, were exposed experimentally to methylmercury (MeHg) to evaluate whether this compound induced cytogenetic effects expressed in the embryos. An additional objective was to assess cytogenetically whetherFundulus embryos from groups that were determined to be more susceptible to the teratogenic effects of MeHg were also more susceptible to its mutagenic effects. Embryos exposed to 0.05 mg/L MeHg for 1 and 7 days post-fertilization were preserved in 10% formalin for cytological examination, while unfixed embryos from the same clutches were evaluated for teratogenic effects. Untreated embyros from each clutch served as controls. Cytogenetic-cytological analyses of fixed treated susceptible embryos that exhibited teratogenic effects revealed decreased mitotic counts (5.0-fold), and increased chromosomal aberrations (2.5-fold) when compared to their controls. There were also decreased mitotic counts (1.5-fold) and increased chromosomal aberrations (2-fold) in embryos from resistant groups when compared to their controls. Exposure to MeHg also retarded development. Forty to fifty percent of the susceptible and resistant control embryos reached the tail-bud stage, but only 28% of the treated resistant and none of the treated susceptible embryos reached this stage. There was also a significant correlation (P < 0.05) between teratogenic and mutagenic effects of MeHg in early stages ofFundulus. 相似文献
77.
目的 分析402例无症状性血尿患儿的病因。 方法 选择2009年1月至2019年12月新乡医学院第一附属医院收治的402例无症状性血尿患儿为研究对象。通过查阅病历资料收集患儿的一般临床资料(性别、年龄、血压、临床表现、家族史)、临床相关检验资料[尿红细胞畸形率、24 h尿蛋白定量、血尿酸、血尿素、血清免疫球蛋白A(IgA)、血清补体C3、胱抑素C(Cys C)水平]。115例患儿在超声引导下行肾穿刺活检术,其中97例患儿肾组织标本经免疫组织化学法处理后进行光学显微镜、免疫荧光、电子显微镜检查,18例患儿肾组织标本经免疫组织化学法处理后进行光学显微镜、免疫荧光检查(未做电子显微镜检查)。402例无症状血尿患儿中,尿红细胞畸形率>70%为肾小球源性组(n=230),尿红细胞畸形率≤70%为非肾小球源性组(n=172)。97例行光学显微镜、免疫荧光、电子显微镜检查的无症状血尿患儿中,24 h尿蛋白定量≤150 mg为单纯血尿组(n=51),24 h尿蛋白定量>150 mg为血尿+蛋白尿组(n=46);经肾组织免疫荧光检查有IgA在肾小球系膜区沉积者为 IgA肾病(IgAN)组(n=42),无IgA在肾小球系膜区沉积者为非IgAN组(n=55)。结果 肾小球源性组中,镜下血尿83例,肉眼血尿147例;病因主要为孤立性血尿(33.5%),IgAN(20.4%),轻微病变(14.3%),急性肾小球肾炎(13.5%)。非肾小球源性组中,镜下血尿63例,肉眼血尿109例;病因主要为感染伴一过性血尿(28.5%)、泌尿道感染(27.3%)、胡桃夹综合征(17.4%)。血尿+蛋白尿组患儿的血清IgA、Cys C水平显著高于单纯血尿组 (P<0.05);单纯血尿组与血尿+蛋白尿组患儿的血尿素、血尿酸及补体C3水平比较差异无统计学意义 (P>0.05)。IgAN组患儿的血清Cys C、IgA水平显著高于非IgAN组(P<0.05);IgAN组与非IgAN组患儿的血尿酸、血尿素、补体C3水平比较差异无统计学意义(P>0.05)。结论 无症状性血尿病因复杂多样,以肾小球源性血尿为主,其早期诊断、治疗及预后评估有赖于肾穿刺活检;血清Cys C和IgA水平可能对肾脏损害程度和IgAN有一定的预测价值。 相似文献
78.
Greg V. Stiegmann John S. Goff John H. Sun Deborah Davis Dean Silas 《Surgical endoscopy》1989,3(2):73-78
Summary Endoscopic variceal ligation (EVL) is a new technique designed to be used instead of sclerotherapy. Small elastic O rings ligate varices resulting in their strangulation and eradication. During a 12-month period, EVL was employed in 53 consecutive patients, of whom 36 (68%) had alcoholic cirrhosis 17 were Child-Pugh class A, 22 class B, and 14 class C. Varices were graded from I to IV and repeat treatments were given at 1–2 week intervals until the varices were eliminated. At follow-up ranging from 6–18 months (mean 11.5), 217 EVL treatment sessions had been performed. Of the 13 patients (24%) who died during the study, 11 died during the index hospitalization. Active bleeding was controlled in 19 of 21 patients (90%). Of 40 survivors 13 patients (33%) had 1–2 (mean 1.4) recurrent variceal bleeds while 34 patients had repeat EVL treatment. Elimination of distal varices was achieved in 26 and 7 had reduction of varices from grade III–IV to grade I–II or less. Eradication required a mean of 4.4 EVL sessions in Child's A and B patients and 7.0 sessions in Child's C patients (P<0.025). No significant treatment-related complications were observed. EVL appears to control active bleeding, is associated with a low incidence of non-bleeding complications, and may be used as an alternative to sclerotherapy. 相似文献
79.
With regard to cadmium toxicity, Drosophila strains v;bw and Austin represent extremes in resistance and sensitivity, respectively. Both strains produced metallothionein (MT) in response to Cd ions in their diet. Austin produced more metallothionein than v;bw at Cd ion levels below 0.2 mM, when both strains were allowed lifetime development on Cd2+-containing media. When the rate of MT appearance was measured for 4 days in young adults the results showed no clear trend with time within a strain or between strains. The plot of LC50 vs. MT levels for identical developmental conditions revealed that for v;bw small increases in MT corresponded to large increases in resistance whereas for the sensitive Austin even large increases in MT had comparatively little effect on increasing LC50. Results given here suggest that differences in total MT content do not explain the genetically demonstrable difference in Cd2+-resistance between v;bw and Austin. However, since two MT genes are identified in Drosophila, differences in resistance could be reflective of greater relative amounts of one "more important" MT in the resistant fly. 相似文献
80.
基于"WD倒谱"法分析人体脾组织的超声散射微结构特征 总被引:1,自引:1,他引:1
本文提出了一种对超声散射信号分析的新方法--“WD倒谱”法,并利用该方法对人体正常脾和脾增生组织的回波信号进行了分析,对软组织中散射子的平均间距进行了估计,结果表明:两种脾组织散射子的平均同距明显不同;“WD倒谱”能有效的反映软组织的微观结构特征,说明“WD倒谱”是软组织超声散射信号分析与软组织散射子平均间距定征的一种有效方法。 相似文献