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51.
Eighteen human immunodeficiency virus (HIV)-seropositive patients were found among 211 previously treated adult patients with a variety of leukemias who had been multiply transfused before April 1985. Patients known to be homosexual or intravenous drug users were excluded from this study. The spouse of one HIV-seropositive patient became HIV infected and subsequently developed the acquired immune deficiency syndrome. Patients with leukemia who were multiply transfused before the availability of screening of blood products for HIV antibody should be counseled regarding their individual risks of HIV infection and the risk to sexual contacts.  相似文献   
52.
L Shi  X Cong  Y Zhang  C Ding  QW Ding  FY Fu  LL Wu  GY Yu 《Oral diseases》2010,16(4):351-359
Oral Diseases (2010) 16 , 351–359 Objectives: To investigate the changes in the muscarinic receptor signaling pathway with submandibular gland (SMG) transplantation and whether carbachol improves secretion in transplanted SMGs. Materials and methods: SMG autotransplantation was performed in a rabbit model. Carbachol (1 μM) was infused into the transplanted glands from postoperative day 1–7. The expression of the M1 and M3 muscarinic receptors, aquaporin‐5 (AQP5), and phosphorylated extracellular signal‐regulated kinase 1/2 (p‐ERK1/2) was measured by RT‐PCR, immunoblotting or immunofluorescence. The content of inositol 1, 4, 5‐trisphosphate (IP3) was measured by radioimmunoassay. Results: Salivary flow of the transplanted SMGs was decreased after transplantation. As well, the expressions of M1 and M3 receptors and their downstream signaling molecules, IP3, p‐ERK1/2 and AQP5, were all reduced. Atrophy of acinar cells was shown in transplanted glands. However, all these alterations were reversed after carbachol treatment for 7 days. Furthermore, carbachol directly increased the mRNA expression of AQP5 and phosphorylation of ERK1/2 in cultured neonatal rabbit SMG cells. Conclusion: A lack of acetylcholine and downregulation of the muscarinic receptor signaling pathway is involved in the early hypofunction of transplanted SMGs. Carbachol treatment could be a new therapeutic strategy to improve secretion and prevent the obstruction of Wharton’s duct in the early phase after SMG transplantation.  相似文献   
53.

BACKGROUND

Unconjugated bilirubin inhibits osteoblastic proliferative activity in vitro, raising the possibility that Gilbert’s syndrome (GS) patients are at increased risk of osteoporosis.

OBJECTIVES

To compare bone mineral density (BMD), serum parathyroid hormone (PTH), C-telopeptide (CTX) and osteocalcin levels in GS subjects versus matched controls in a cross-sectional, case-control study.

METHODS

BMD determinations were obtained with central dual-energy x-ray absorptiometry. Serum PTH, CTX and osteocalcin levels were measured by enzyme immunoassay.

RESULTS

A total of 17 GS and 30 control subjects were studied. Overall, there were no significant differences in BMD, PTH, CTX or osteocalcin levels between the two groups. However, when older (older than 40 years of age) and younger (40 years of age and younger) cohorts were considered separately, the older GS cohort had significantly decreased total hip BMD, T scores and Z scores, and femoral neck BMD, T scores and Z scores (P<0.005 for each parameter, respectively) compared with older control subjects. Serum osteocalcin levels were lower in the older versus younger GS cohort (P=0.006). An inverse correlation existed between all subjects’ serum unconjugated bilirubin levels and total body BMD determinations (r=−0.42; P=0.04). On univariate analysis, the association between serum unconjugated bilirubin and total body BMD was not significant (P=0.066), nor was serum unconjugated bilirubin identified as a risk factor for low BMD when entered into multivariate analyses.

CONCLUSIONS

The results of the present pilot study warrant further research involving larger numbers of subjects and longitudinal measurements to determine whether GS is associated with decreased BMD, particularly in older GS subjects.  相似文献   
54.
METHODSInanimalstudies,adultmaleSpragueDawleyrats(n=3-4/group)weresacrificedat0,12,24,36,48,72and96hoursfollowing70%partia...  相似文献   
55.
目的:建立测定甲磺酸加贝酯含量的新方法。方法:以NOVAPARK(150mm ×4 .5m m ,6μm) 为色谱柱,甲醇水磷酸(50∶50∶0 .2) 为流动相,检测波长为236nm ,外标法定量。结果:线形范围0 .4 ~2 .0μg ,r = 0 .9997 ,回收率99 .67 % ,日间RSD 为0 .61 % 。结论:该法简便,可用以测定甲磺酸加贝酯含量。  相似文献   
56.
Landau  JM; Wang  ZY; Yang  GY; Ding  W; Yang  CS 《Carcinogenesis》1998,19(3):501-507
We investigated the effects of black tea (BT) and green tea (GT) infusion on the spontaneous formation of lung tumors and rhabdomyosarcomas in A/J mice. Female A/J mice, 6 weeks of age, were allocated into five groups (50 per group) and were given the following as the sole source of drinking fluid: (i) deionized water (control group), (ii) 0.5% BT, (iii) 1% BT, (iv) 2% BT and (v) 1% GT. After 60 weeks, the mice were killed by decapitation. Lung tumor incidence, multiplicity and volume were significantly lower in the 2% BT group as compared with the controls (27 versus 52%, 0.33 versus 0.72 tumors/mouse and 4.27 versus 38.3 mm3, respectively). The 1% GT group had significantly lower lung tumor multiplicity (0.41/mouse), while the 1% BT group had significantly decreased tumor volume (7.17 mm3). Rhabdomyosarcomas were found in 34% of the mice in the control group, and both the 1 and 2% BT groups had significantly lower incidences at 13 and 14%, respectively. The mice in the 2% BT group weighed 16% less than those in the control group, although they consumed more food than the control group. The other tea-consuming groups also weighed less than the control group (7.8-11%) while consuming more food and fluid. In a separate experiment, similar carcinogenesis inhibition was also observed in female A/J mice that were given 0.6% and then 0.3% instant black tea for 52 weeks. These results demonstrate the inhibitory activity of BT against the spontaneous formation of lung tumors and rhabdomyosarcomas in mice.   相似文献   
57.
Goldstein  SR; Yang  GY; Chen  X; Curtis  SK; Yang  CS 《Carcinogenesis》1998,19(8):1445-1449
A rat model was developed recently in our laboratory to study the pathogenesis of Barrett's esophagus (BE) and its progression to esophageal adenocarcinoma (EAC). Eight-week-old male Sprague-Dawley rats underwent esophagoduodenal anastomosis (EDA) to produce gastric and duodenal reflux in their distal esophagi. The rats were given iron dextran (50 mg of Fe/kg, i.p.) starting 2 weeks after surgery and this was continued once a month. BE was observed as early as week 3 and the incidence of BE and EAC increased with time: 58 and 17% at week 23; 91 and 73% at week 31. There was a progression in epithelial cell proliferation and inflammation from mild to severe in the distal one- third of the esophagus. Iron deposition in the esophagus also increased with time. Iron deposits in the stromal tissue adjacent to the epithelium in the distal one-third of the esophagus were associated with areas of severe inflammation. Immunohistochemical analysis showed positive inducible nitric oxide synthase (iNOS) expression in the stromal macrophages directly beneath the epithelium in the distal one- third of the esophagus in 36, 83 and 100% of the rats at weeks 17, 23 and 31, respectively. A significant increasing linear trend (P=0.001) was seen in nitrotyrosine immunostaining (number of positive cells/high power field) in the distal esophagus. Strong positive nitrotyrosine staining was seen in the macrophages and weaker positive staining was seen in the adjacent epithelium starting at week 17. Furthermore, iron supplemented rats killed at week 31 had significantly higher (P < 0.05) levels of inflammation, cell proliferation, iNOS and nitrotyrosine as well as more tumors in their distal esophagi than did rats that received no iron supplement. These results suggest that iron supplementation enhanced inflammation and the production of reactive oxygen and nitrogen species in the esophageal epithelium. These processes could contribute to the formation of BE and its progression to EAC.   相似文献   
58.
目的 探讨应用PCR分子生物学方法产前诊断Down综合征(Down syndrome,DS)。方法 取产前诊断病例:羊水100例,绒毛16例。提取DNA,PCR扩增21号染色体的6个多态位点,电泳,膜转移,等位基因位点分析,诊断。结果 正常人为两种带型:杂合型显示两条带,纯合型一条带。Down综合征患者为三种带型:完全杂合型显示三条带,半杂合型两条带(信号增强的2:1带),纯合型一条带。100例羊水中2例阳性,16例绒毛标本中1例阳性,3例患者,至少有2个位点检出三个等 基因,患者为2个位点时,表现2:1带型;无一例正常检出三个等位基因。所有结果均与细胞染色体核型检查相符。结论 本分子生物学方法产前诊断DS简便、快速、可行,是一种值得推广的方法。  相似文献   
59.
The electroretinograms (ERGs) of patients with Duchenne muscular dystrophy and an allelic variant of the mdx mouse (mdxCv3) have been shown to be abnormal. Analysis of five allelic variants of the mdx mouse with mutations in the dystrophin gene has shown that there is a correlation between the position of the mutation and the severity of the ERG abnormality. Three isoforms are expressed in the retina: Dp427, Dp260 and Dp71. Using indirect immunofluorescence and isoform-specific antibodies on retinal sections from three allelic mdx mouse strains, we have examined the localization of each of the isoforms. We show that Dp71 expression does not overlap with Dp427 and Dp260 expression at the outer plexiform layer (OPL). Instead, Dp71 is localized to the inner limiting membrane (ILM) and to retinal blood vessels. Moreover, we show that Dp260 and Dp71 differ structurally at their respective C-termini. In addition, we find that the proper localization of the beta- dystroglycan is dependent upon both Dp260 at the OPL and Dp71 expression at the ILM. Thus, Dp260 and Dp71 are non-redundant isoforms that are located at different sites within the retina yet have a common interaction with beta-dystroglycan. Our data suggest that both Dp71 and Dp260 contribute distinct but essential roles to retinal electrophysiology.   相似文献   
60.
阿托品对兔胸主动脉平滑肌收缩和细胞增殖的影响   总被引:1,自引:0,他引:1  
用兔胸主动脉条研究Atr,Ver对CaCl2,Atr对KCI量—效反应的影响。观察到Atr和Ver能抑制2种激动剂所致兔主动脉条的收缩,量一效曲线右移,最大反应降低,其pD2值分别为4.4和5.8。两药也能明显抑制NE依内Ca2+性收缩,Atr对NE依外Ca2+性收缩影响较小,说明Atr主要对细胞外Ca2+经PDC所致的收缩有抑制作用。在兔ASMC培养中,有Ca2+时,Atr抑制ASMC增殖,无Ca2+时,Atr 20.6~185.2 μmol/L表现刺激增殖,555.7~1666.7 μmol/L则抑制MSMC增殖,说明Atr对ASMC作用也与Ca(2+)有关。  相似文献   
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