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71.
In this study the distribution patterns of various extracellular matrix components and their receptors (i.e. β1 integrins) in B-cell non-Hodgkin lymphomas were examined and compared to those in reactive lymphoid tissue. Neoplastic follicles within follicular lymphomas showed similar patterns to that observed in reactive follicles, which appeared to be strongly associated with the presence of follicular dendritic cells. Diffuse lymphomas of low and intermediate malignancy grade revealed features comparable to those of interfollicular areas of reactive lymphoid tissue, irrespective to which compartment the tumour cells were related. Highly malignant lymphomas, however, displayed unique extracellular matrix configurations, resulting from active matrix degradation by macrophages; this may support rapid tumour growth. Extranodal lymphomas showed virtually the same matrix patterns as their nodal counterparts, suggesting that (malignant) lymphoid cells generate (at least partly) their own specific microenvironment. In reactive lymphoid tissue β1 integrins were mainly found on resident cells and except for α4, α5 (and β1) the lymphoid cells expressed very little, if any, β1 integrins. In comparison, expression of these integrins on lymphoma cells was reduced (follicular lymphomas) or could not be detected at all (diffusely growing lymphomas); this might contribute to the growth pattern and metastatic properties of the tumours.  相似文献   
72.
Four patients with untreated renal tubular acidosis had a urinary excretion of low-molecular-weight (LMW) proteins which was restored to normal by alkali therapy. Hypokalaemic proximal tubular damage in untreated patients with distal renal tubular acidosis is believed to be the cause of LMW proteinuria. An examination of urinary excretion of LMW proteins is useful for determining hypokalaemic proximal tubular dysfunction, as well as the efficiency of alkali therapy.  相似文献   
73.
Objective: Our purpose was to determine whether insulin-like growth factors I and II preferentially stimulate uterine leiomyoma cells versus myometrial cells in monolayer culture.Study design: Leiomyomas and normal myometrium were obtained at hysterectomy from five premenopausal women. Specimens were enzymatically digested for use in primary monolayer cell cultures. By use of serum-free media, insulin-like growth factor I or II was added in 1, 10, and 100 ng/ml concentrations to both cell types with the patient serving as her own control. Cell number, prolactin production, and proliferative index values were measured on day 15 of cell culture.Results: Significant increases in cell number were found in the leiomyoma cultures (p < 0.05) treated with 10 and 100 ng/ml insulin-like growth factors I but not with insulin-like growth factos II. Neither factor exerted a stimulatory effect on myometrial cells.Conclusion: Insulin-like growth factor sI preferentially stimulates leiomyoma cells in monolayer culture. These results suggest an autocrine-paracine role in vivo for this factor in conjuction with gonadal steroids in promoting leiomyoma growth.  相似文献   
74.
75.
We conducted a case-control study of the alpha-synuclein-interacting protein gene (SNCAIP, also known as synphilin-1) and Parkinson's disease (PD). A total of 319 PD cases and 195 controls were genotyped for four SNCAIP variants, including a microsatellite repeat in intron 4 and three restriction fragment length polymorphisms (RFLP) proximal to the 5' terminal of exons 1, 4, and 6. None of the variants were found associated with PD overall. Global score statistics were not significant for four, three, and two loci haplotypes. All four loci were in linkage disequilibrium for cases, controls, or both groups combined (P < 0.0001). Recursive partitioning showed no interactions between variants of the SNCAIP gene and variants of the alpha-synuclein gene (SNCA) or the parkin (PARK2) gene.  相似文献   
76.
选择南方热区某特种部队战士52人,分两组分别口服5mgVitB1和VitB2,收集4h尿液,用荧光法进行负荷试验。结果:VitB1组,所测29人中,15人缺乏,9人不足,2人正常,3人充裕;VitB2组,所测23人中,11人缺乏,12人不足,反映该部队全年约5%的发病是由于VitB1、VitB2缺乏不足所致。其原因为膳食摄入不够  相似文献   
77.
本文探讨了ASA剂量与药效的关系及血ASA、SA药物浓度监测的临床意义,结果表明:(1)ASA剂量与6-keto-PGF_(1α)抑制率呈正相关(P<0.01),而与TXB_2及PAgR抑制率无相关性(P>0.1);(2)本文采用HPLC内标法同时测定血ASA和SA浓度,结果准确,方法简便;(3)当口服小剂量ASA防治CI时,监测血ASA和SA以调整ASA用药剂量的临床价值并非十分重要。  相似文献   
78.
79.
The course of the organic brain disease caused by human immunodeficency virus (HIV-1) was evaluated in a follow-up study. The primary material included 200 consecutive HIV-1 infected persons. Sixty-one subjects, in whom other brain-affecting factors were excluded, consented to the follow-up. They underwent 278 radiologic examinations: computed tomography, magnetic resonance imaging, or a combination of both (mean 4.6 examinations/subject). Clinical neurologic status and, in 40 subjects, cognitive performance were repeatedly evaluated. Sixteen subjects were followed up until death and 11 of them were autopsied. Median follow-up time was 27 mo (range 2.5–66 mo). The most common radiologic finding was atrophy, found in 19 subjects at study entry and developing in 10 subjects during the study. Twenty-four subjects (39%) showed the development and/or progression of atrophy. Atrophic changes progressed most rapidly in acquired immunodeficiency syndrome (AIDS), but mild developing/progressive atrophy was found even in 33% of asymptomatic or neurologically intact subjects. Cognitive and radiologic worsening were simultaneous in 6/7 subjects with declining neuropsychologic test performance. Signal intensity changes including HIV-1 leukoencephalopathy appeared in AIDS patients with clear cognitive decline.  相似文献   
80.
The complete sequence of the cDNA encoding the neuropeptide Y (NPY) Y1-receptor has recently been deduced from a rat brain library, and the presence of messenger ribonucleic acid (mRNA) encoding Y1-receptor protein has been demonstrated within the brain. Using quantitative in situ hybridization histochemistry, the content and distribution of Y1receptor and preproNPY mRNAs have been investigated in the hypothalamic arcuate nucleus of adrenalectomized rats receiving glucocorticoid replacement therapy for 12 days by means of either high doses of dexamethasone in their drinking water or by subcutaneous corticosterone pellets. Basal metabolic parameters such as weight gain or loss, blood glucose and plasma insulin were monitored: Dexamethasone treatment induced weight loss and a state of hyperinsulinemia with normoglycemia, while corticosterone treated animals displayed metabolic parameters identical to sham ADX animals. Within the arcuate nucleus of glucocorticoid treated animals, levels of Y1receptor and preproNPY mRNAs were increased. In contrast, adrenalectomy itself had no effect upon Y1-receptor mRNA levels or preproNPY mRNA levels in the arcuate nucleus. These studies demonstrate that glucocorticoids exert a stimulatory action on levels of Y1-receptor mRNA and preproNPY mRNA levels in the hypothalamic arcuate nucleus. This is the first evidence to suggest that the expression of a neuropeptide-receptor gene in the central nervous system may be directly sensitive to peripheral hormonal signals.  相似文献   
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