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51.
52.
A feline model of Niemann–Pick disease type C (NPC) was employed to evaluate the effect of dietary cholesterol restriction on progression of disease. Two NPC-affected treated cats were fed a cholesterol-restricted diet beginning at 8 weeks of age; the cats remained on the diet for 150 and 270 days respectively. The study goal was to lower the amount of low density lipoprotein (LDL) available to cells, hypothetically reducing subsequent lysosomal accumulation of unesterified cholesterol and other lipids. Neurological progression of disease was not altered and dietary cholesterol restriction did not significantly decrease storage in NPC-affected treated cats. One NPC-affected treated cat had decreased serum alkaline phosphatase activity (ALP) and decreased serum cholesterol concentration. Liver lipid concentrations of unesterified cholesterol, cholesterol ester and phospholipids in NPC-affected treated cats were similar to those seen in NPC-affected untreated cats. Ganglioside concentrations in the NPC-affected treated cats and NPC-affected untreated cats were similar. Histological findings in liver sections from NPC-affected treated cats showed a diffuse uniform microvacuolar pattern within hepatocytes and Kupffer cells, in contrast to a heterogeneous macro/microvacuolar pattern and prominent nodular fibrosis in NPC-affected untreated cats. Similar differences in vacuolar patterns were seen in splenic macrophages. Although some hepatic parameters were modified, dietary cholesterol restriction did not appear to alter disease progression in NPC-affected kittens.  相似文献   
53.
替硝唑软膏的研制与临床应用   总被引:9,自引:0,他引:9  
目的:研究替硝唑软膏,并应用于临床。方法:参照同类制剂,确定最优组方和制备方法,采用紫外分光光度法测定含量,用比较法进行临床疗效观察。结果:制剂制备简单,含量测定方法简便,结果可靠,经临床应用牙周炎、牙龈炎患者62例,总有效率95.3%。结论:本品是治疗牙周炎、牙龈炎的理想制剂,值得推广应用。  相似文献   
54.
Latent membrane protein 1 (LMP1), an oncoprotein encoded by Epstein-Barr virus (EBV), is an integral membrane protein, which acts like a constitutively active receptor. LMP1 is critical for some facet of EBV's induction and maintenance of proliferation of infected B cells. It, in part, mimics signaling by the CD40 receptor and has been implicated in regulating proliferation, survival, or both properties of EBV-infected cells. We established a conditional LMP1 allele in the context of the intact EBV genome to define the immediate-early cellular target genes regulated by LMP1 in order to assess its contributions to infected human B cells. The functional analysis of this conditional system indicated that LMP1 specifically induces mitogenic B-cell activation through c-myc and Jun/AP1 family members and confirms its direct role in upregulating expression of multiple genes with opposing activities involved in cell survival. LMP1's signals were found to be essential for the G1/S transition in human B cells; cells lacking LMP1's signals are cell cycle arrested and survive quiescently. LMP1's activities are therefore not required to maintain survival in nonproliferating cells. LMP1 does induce both pro- and antiapoptotic genes whose balance seems to permit survival during LMP1's induction and maintenance of proliferation.  相似文献   
55.
Pilatz A  Schultheiss D  Gabouev AI  Schlote N  Mertsching H  Jonas U  Stief CG 《European urology》2005,47(5):710-8; discussion 718-9
OBJECTIVES: Primary cell cultures derived from the corpus cavernosum are frequently used as in vitro models to define cellular mechanisms involved in erectile function. However, previous studies often lack detailed isolation protocols or a precise characterisation of the culture composition excluding especially contaminating fibroblasts. This study aimed at critically analysing and reproducing reported isolation methods, as well as establishing new procedures to receive highly pure and morphologically differentiated endothelial, smooth muscle and fibroblastic cells derived from the human penis. METHODS: We evaluated numerous isolation and enrichment techniques using cavernosal tissue from 57 patients. Assessment factors displayed the purity, cell yield, practicability and reproducibility. The purity in cultured cells was analysed using immunocytochemistry and Western blots. RESULTS: An enzymatic protocol was established for the isolation and cultivation of cavernosal endothelial cells with an impressive purity of 98.0+/-0.8%. In contrast, already published nearly pure smooth muscle cell cultures were not reproducible in our laboratory. Meaningful evidence for an overwhelming presence of fibroblasts in these widely accepted pure smooth muscle cell cultures is presented. CONCLUSION: Endothelial cell cultures derived from human corpora cavernosa are reproducible and reliable to serve for cell culture-based investigations of the endothelial dysfunction. The discrepancy in the purity of smooth muscle cell cultures might reflect laboratory and tissue source factors, lacking an exclusion of fibroblasts in other studies or changes in stromal phenotype under culture conditions. Further research is necessary to clarify a possible plasticity between smooth muscle cells and (myo)fibroblasts and assess functional properties.  相似文献   
56.
Schultheiss D 《Der Urologe. Ausg. A》2005,44(10):1139-40, 1142-6
A detailed medical history and clinical examination are important steps in the diagnosis of male infertility. Tests include semen analysis according to WHO standards, laboratory tests (mainly determination of follicle-stimulating hormone) and scrotal sonography. Invasive diagnostic procedures, such as testicular biopsy or investigation of seminal pathway obstruction, are generally combined with therapeutic sperm retrieval for cryopreservation or microsurgical refertilization.  相似文献   
57.
The identification of common genetic variants such as single nucleotide polymorphisms (SNPs) in the human genome has become central in human population genetics and evolution studies, as well as in the study of the genetic basis of complex traits and diseases. Crucial for the accurate identification of genetic variants is the availability of high quality genomic DNA (gDNA). Since popular sources of gDNA (buccal cells, lymphocytes, hair bulb) often do not yield sufficient quantities of DNA for molecular genetic applications, whole genome amplification methods have recently been introduced to generate a renewable source of double-stranded linear DNA. Here, we assess the fidelity of one method, multiple displacement amplification (MDA), which utilizes bacteriophage Phi29 DNA polymerase to generate amplified DNA from an original source of gDNA, in a representative SNP discovery and genetic association study at the melanocortin 1 receptor (MC1R) locus, a highly polymorphic gene in humans involved in skin and hair pigmentation. We observed that MDA has high fidelity for novel SNP discovery and can be a valuable tool in generating a potentially indefinite source of DNA. However, we observed an allele amplification bias that causes genotype miscalls at heterozygous sites. At loci with multiple polymorphic sites in linkage disequilibrium, such as at MC1R, this bias can create a significant number of heterozygote genotype errors that subsequently misrepresents haplotypes.  相似文献   
58.
The inhibition of the glycoprotein (GP) IIb/IIIa receptor for reducing periprocedural ischemic events in patients undergoing coronary intervention is known to influence platelet reactivity. Suboptimal doses of GP IIb/IIIa antagonists have been suggested to be prothrombotic and proinflammatory. This study was performed to observe platelet activation markers, whole blood aggregation and the dosage of unfractionated heparin (UFH) in the presence or absence of the GP IIb/IIIa inhibitor abciximab. Patients with acute myocardial infarction undergoing percutaneous coronary intervention were treated with (n = 15) or without (n = 15) abciximab. Platelet activation markers were flow cytometrically measured before and after PCI. Whole blood platelet aggregation was tested by a platelet function assay. The patients with abciximab showed a significant increase in platelet activation markers (P-selectin: 7.12 +/- 0.36 AU vs 11.05 +/- 0.79 AU) and a lower requirement of UFH to prolong aPTT > 60 sec during the infusion. 12 hours after infusion P-selectin level decreased (7.20 +/- 0.58 AU), whereas whole blood aggregation was increasing again. After stopping abciximab, requirement of UFH to prolong aPTT increased in the treated group to a greater extent to a level similar to the untreated group even when most of the platelets were still inhibited. The increased platelet activation found at the end of abciximab treatment points to a procoaguable condition that should be carefully monitored and treated by adapting anticoagulation and antiplatelet drugs.  相似文献   
59.
BACKGROUND: Nephrotic syndrome (NS) represents the association of proteinuria, hypoalbuminemia, edema, and hyperlipidemia. Steroid-resistant nephrotic syndrome (SRNS) is defined by primary resistance to standard steroid therapy. It remains one of the most intractable causes for end-stage renal disease (ESRD) in the first two decades of life. Sporadic mutations in the Wilms' tumor suppressor gene WT1 have been found to be present in patients with SRNS in association with Wilms' tumor (WT) and urinary or genital malformations, as well as in patients with isolated SRNS. METHODS: To further evaluate the incidence of WT1 mutations in patients with NS we performed mutational analysis in 115 sporadic cases of SRNS and in 110 sporadic cases of steroid-sensitive nephrotic syndrome (SSNS) as a control group. Sixty out of 115 (52%) patients with sporadic SRNS were male, 55/115 (48%) were female. Sex genotype was verified by haplotype analysis. Mutational analysis was performed by direct sequencing and by denaturing high-performance liquid chromatography (DHPLC). RESULTS: Mutations in WT1 were found in 3/60 (5%) male (sex genotype) cases and 5/55 (9%) female (sex genotype) cases of sporadic SRNS, and 0/110 (0%) sporadic cases of SSNS. One out of five female patients with mutations in WT1 developed a WT, 2/3 male patients presented with the association of urinary and genital malformations, 1/3 male patients presented with sexual reversal (female phenotype) and bilateral gonadoblastoma, and 4/5 female patients presented with isolated SRNS. CONCLUSION: According to the data acquired in this study, patients presenting with a female phenotype and SRNS and male patients presenting with genital abnormalities should especially be screened to take advantage of the important genetic information on potential Wilms' tumor risk and differential therapy. This will also help to provide more data on the phenotype/genotype correlation in this patient population.  相似文献   
60.
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