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61.
Cadmium is a widespread toxic pollutant of occupational and environmental concern because of its diverse toxic effects: extremely protracted biological half-life (approximately 20–30 years in humans), low rate of excretion from the body and storage predominantly in soft tissues (primarily, liver and kidneys). It is an extremely toxic element of continuing concern because environmental levels have risen steadily due to continued worldwide anthropogenic mobilization. Cadmium is absorbed in significant quantities from cigarette smoke, food, water and air contamination and is known to have numerous undesirable effects in both humans and animals. Cadmium has a diversity of toxic effects including nephrotoxicity, carcinogenicity, teratogenicity and endocrine and reproductive toxicities. At the cellular level, cadmium affects cell proliferation, differentiation, apoptosis and other cellular activities. Current evidence suggests that exposure to cadmium induces genomic instability through complex and multifactorial mechanisms. Most important seems to be cadmium interaction with DNA repair mechanism, generation of reactive oxygen species and induction of apoptosis. In this article, we have reviewed recent developments and findings on cadmium toxicology.  相似文献   
62.
In the age of a pandemic, such as the ongoing one caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the world faces a limited supply of tests, personal protective equipment, and factories and supply chains are struggling to meet the growing demands. This study aimed to evaluate the efficacy of specimen pooling for testing of SARS-CoV-2 virus, to determine whether costs and resource savings could be achieved without impacting the sensitivity of the testing. Ten previously tested nasopharyngeal and throat swab specimens by real-time polymerase chain reaction (PCR), were pooled for testing, containing either one or two known positive specimens of varying viral concentrations. Specimen pooling did not affect the sensitivity of detecting SARS-CoV-2 when the PCR cycle threshold (Ct) of original specimen was lower than 35. In specimens with low viral load (Ct > 35), 2 of 15 pools (13.3%) were false negative. Pooling specimens to test for Coronavirus Disease 2019 infection in low prevalence (≤1%) areas or in low risk populations can dramatically decrease the resource burden on laboratory operations by up to 80%. This paves the way for large-scale population screening, allowing for assured policy decisions by governmental bodies to ease lockdown restrictions in areas with a low incidence of infection, or with lower-risk populations.  相似文献   
63.
Chronic granulomatous disease (CGD) results from an inherited defect in the phagocytic cells of the immune system. It is a genetically heterogenous disease caused by defects in one of the five major subunits of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex. There is a paucity of data from India on CGD. We herein describe the clinical features in 17 children with CGD from a single tertiary referral center in India. A detailed analysis of the clinical features, laboratory investigations and outcome of 17 children 7 with X-linked (XL) and 10 with autosomal recessive (AR) form was performed. Diagnosis of CGD was based on an abnormal granulocyte oxidative burst evaluated by either Nitroblue Tetrazolium (NBT) test or flow cytometry based Dihyrorhodamine 123 assay or both. The molecular diagnosis was confirmed by genetic mutation analysis in 13 cases. The mean age at diagnosis and the age at onset of symptoms was significantly lower in children diagnosed with XL- CGD compared those with AR disease. Mutations were detected in CYBB gene in 6 patients with XL-CGD and NCF-1 gene mutations were observed in 7 cases of AR- CGD. The course and outcome of the disease was much worse in children diagnosed with X-linked form of disease compared to AR forms of the disease; 4/7 (57 %) children with X-CGD were dead at the time of data analysis. This is one of the largest series on chronic granulomatous disease from any developing country.  相似文献   
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Alveolar soft part sarcoma is a rare soft tissue tumor with uncertain histogenesis. It is a slow growing tumor with a high rate of metastasis. The tumor is not easily identified as clinical symptoms are not pronounced. The retroperitoneum is a rare location of tumor, with a few cases published in literature. Surgical excision is the mainstay of treatment. Here we describe a rare case of a large retroperitoneal Alveolar soft part sarcoma in a young female with radiological and histopathological findings.  相似文献   
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Abstract: Congenital lipomatous overgrowth, vascular malformations, and epidermal nevi (CLOVE) syndrome is a recently described syndrome similar to Proteus syndrome but lacking the progressive or distorting bony overgrowth of Proteus syndrome. We describe a neonate with features of CLOVE syndrome and nevus unius lateris.  相似文献   
69.
Langerhans cells develop from a lymphoid-committed precursor   总被引:7,自引:3,他引:4       下载免费PDF全文
Anjuère F  del Hoyo GM  Martín P  Ardavín C 《Blood》2000,96(5):1633-1637
Langerhans cells (LCs) are specialized dendritic cells (DCs) strategically located in stratified epithelia, such as those of the skin, oral cavity, pharynx, esophagus, upper airways, urethra, and female reproductive tract, which are exposed to a wide variety of microbial pathogens. LCs play an essential role in the induction of T-lymphocyte responses against viruses, bacteria, and parasites that gain access to those epithelial surfaces, due to their high antigen capture and processing potential and their capacity to present antigen peptides to T cells on migration to the lymph nodes.(1) Although LCs have been classically considered of myeloid origin, recent reports, which demonstrate the existence of lymphoid DCs derived from multipotent lymphoid precursors devoid of myeloid differentiation potential,(2-5) raise the question of the lymphoid or myeloid origin of LCs. The present study shows that mouse lymphoid-committed CD4(low) precursors, with the capacity to generate T cells, B cells, CD8(+) lymphoid DCs, and natural killer cells,(26) also generate epidermal LCs on intravenous transfer, supporting the view that LCs belong to the lymphoid lineage. (Blood. 2000;96:1633-1637)  相似文献   
70.
A total of 20 previously untreated children with growth hormone deficiency (GHD) were treated for one year with biosynthetic human growth hormone (hGH). The mean chronologic age was 9.43±3.52 years with a height age of 5.02 years, and bone age 9.43±3.52 (TW2-RUS) 6.42 years. The mean pretreatment growth velocity was 2.43±0.90 cm/year. Of these 14 children had complete GHD (peak GH levels less than 5 ng/ml) and 6 had partial GHD. They were treated with recombinant GH in a dose of 0.5 IU/kg/week divided into 6–7 injections per week subcutaneously at night. The mean growth velocity increased to 8.88±2.10 cm/yr at the end of 6 months and 8.00±2.21 cm/yr at 12 months. The actual gain ranged from 6–11 cm in a year. There were no local adverse reactions. One child developed vitiligo of the face and another transient hyperglycemia.  相似文献   
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