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1.
Metabolic abnormalities of gastrointestinal mucosa in celiac disease: An in vitro proton nuclear magnetic resonance spectroscopy study 下载免费PDF全文
2.
Increased rate of DNA recovery from United Kingdom epidemic Clostridium difficile PCR ribotype 1 strains stored cryogenically 下载免费PDF全文
We noted that some Clostridium difficile isolates are nonrecoverable after frozen storage and so used molecular typing analysis to characterize DNA from these strains. The recovery rate of C. difficile PCR ribotype 1 was statistically significantly greater than that of other strains. This observation has implications for C. difficile epidemiological studies. 相似文献
3.
Tandon A Singh A Atrishi E Saxena SK Mathur A 《International journal of experimental pathology》2002,83(1):39-46
A unique factor, human T cell hypoglycaemic factor (hTCHF), has been shown to produce hypoglycaemia during the convalescent stage in the plasma of patients with Japanese encephalitis virus (JEV) infection. The present study was undertaken to investigate the ability of T cells from fresh peripheral blood mononuclear cells (PBMC) of such patients to produce hTCHF. The PBMC, as well as the individual subpopulations, were cultured for 24 h and the culture supernatants (CS) were assayed for hypoglycaemic activity. The activity was observed in the CD8+ T cells. The hypoglycaemia in JE-confirmed patients coincided with the gradual rise in circulating glucagon level, with no significant alterations in insulin, growth hormone and cortisol levels. The hTCHF was purified by ion exchange chromatography and the purified protein was observed as a approximately 25 kDa band on SDS-PAGE. Secretory hTCHF in the sera of patients and T cell CS was present in 88% of convalescent serum samples. We conclude that during the convalescent stage of JEV infection, a unique factor, hTCHF, is secreted by activated CD8+ T cells from patients and that this is responsible for the development of hypoglycaemia. 相似文献
4.
5.
Elevated telomere-telomere recombination in WRN-deficient, telomere dysfunctional cells promotes escape from senescence and engagement of the ALT pathway 总被引:4,自引:0,他引:4 下载免费PDF全文
Laud PR Multani AS Bailey SM Wu L Ma J Kingsley C Lebel M Pathak S DePinho RA Chang S 《Genes & development》2005,19(21):2560-2570
Werner Syndrome (WS) is characterized by premature aging, genomic instability, and cancer. The combined impact of WRN helicase deficiency and limiting telomere reserves is central to disease pathogenesis. Here, we report that cells doubly deficient for telomerase and WRN helicase show chromosomal aberrations and elevated recombination rates between telomeres of sister chromatids. Somatic reconstitution of WRN function, but not a WRN helicase-deficient mutant, abolished telomere sister chromatid exchange (T-SCE), indicating that WRN normally represses T-SCEs. Elevated T-SCE was associated with greater immortalization potential and resultant tumors maintained telomeres via the alternative lengthening of telomere (ALT) pathway. We propose that the increased incidence of chromosomal instability and cancer in WS relates in part to aberrant recombinations between sister chromatids at telomeres, which facilitates the activation of ALT and engenders cancer-relevant chromosomal aberrations and tumor formation. 相似文献
6.
A 25-year-old man presented with a sudden spurt in size of a bony swelling around the external ear, which was present since birth. This was associated with a painful swelling of the right half of the face and pain, redness, and decreased vision in the right eye. Neurologic examination showed decreased visual acuity in the right eye and paresis of the fifth, seventh, and eighth cranial nerves. Neuroimaging showed an extra-axial, partly cystic tumor of mixed density, located entirely within the middle cranial fossa scalloping the temporal bone and extending into the right infratemporal fossa and the right middle ear and impinging on the ipsilateral cavernous sinus. The right temporal lobe was elevated and compressed. Histopathologic examination confirmed a mature teratoma. 相似文献
7.
Saurabh Kumar Bhushan Shah Ashok Johari Rashid Anjum Devansh Garg Rashmi Salhotra Asha Tyagi Amir Maroof Khan Anil Kumar Jain 《Indian Journal of Orthopaedics》2021,55(2):506
Covid-19 is a respiratory disease caused by coronavirus 2 (SARS-CoV-2) first identified in Wuhan, China (December 2019). The disease rapidly crossed the barrier of countries, continents and spread globally. Non-pharmaceutical measures such as social distancing, face mask, frequent hand washing and use of sanitizer remained the best available option to prevent the spread of disease. OPD, IPD admissions, elective O. Ts were curtailed. Orthopedic care was only limited to emergency and semi-urgent procedures like necrotizing fasciitis, open fracture, and compartment syndrome. These measures were taken to preserve infrastructure and manpower to manage covid-19 pandemic. The children were thought to have a low susceptibility to covid-19 as compared to an adult. Deferring the patient during pandemic has led to high orthopedic disease burden, morbidity and disease-related sequelae, hence elective care must be resumed with modified hospital infrastructure. Resumption of elective/emergent orthopedic care should be slow, phasic and strategic, much similar to unlocking. Cases must be stratified depending on covid status and severity. Dedicated O.Ts with neutral/negative pressure and HEPA filter for covid positive and suspected patients are to be used. All symptomatic and suspected patients should be investigated for covid-19 by RT-PCR, blood counts and CT scan. Regional anaesthesia should be preferred to General anaesthesia. Power drill/saw/burr/pulse lavage should be minimized to avoid aerosol generation. Postoperatively continuous surveillance and monitoring to be done for covid related symptoms. Medical institutes rapidly shifted to the online mode of education. Blended learning (virtual & physical) and imparting skills have to be continued in post covid phase with equitable distribution of teaching hours to students of different years. 相似文献
8.
A comparative study of perinatal mortality patterns over a period was conducted at a teaching hospital of South India. Among
the 6,048 babies born from January 1984 to December 1985 (Group A), there were 265 (43.8/1000) still births and 127 (22.0/1000)
early neonatal deaths. Three hundred and thirty seven (41/1000) babies were still born and 235 (29.8/1000) early neonatal
deaths out of 8,215 deliveries during 1992–93 (Group B). The perinatal mortality rate (PMR) in Group A and B were 57.9/1000
and 57.7/1000 respectively. Unbooked cases accounted for the majority (> 75%) of perinatal deaths during both the periods.
The overall mortality rates in unbooked cases were three to four times higher than booked cases. Among the various causes
of still births, antepartum haemorrhage and uterine rupture had increased. Septicaemia was the major cause of early neonatal
deaths in Group A, but in Group B birth asphyxia and prematurity were the leading causes. Effective interventions like creating
awareness among the target population to utilise maternal and child health services and early referral of high risk cases
with improved intranatal and perinatal care can decrease the perinatal mortality. 相似文献
9.
Asha R Kallianpur Lynn D Hall Meeta Yadav Brian W Christman Robert S Dittus Jonathan L Haines Fritz F Parl Marshall L Summar 《Cancer epidemiology, biomarkers & prevention》2004,13(2):205-212
Individuals with the major hemochromatosis (HFE) allele C282Y and iron overload develop hepatocellular and some extrahepatic malignancies at increased rates. No association has been previously reported between the C282Y allele and breast cancer. We hypothesized that due to the pro-oxidant properties of iron, altered iron metabolism in C282Y carriers may promote breast carcinogenesis. Because 1 in 10 Caucasians of Northern European ancestry carries this allele, any impact it may have on breast cancer burden is potentially great. We determined C282Y genotypes in 168 patients who underwent high-dose chemotherapy and blood cell transplantation for cancer: 41 with breast cancer and 127 with predominantly hematological cancers (transplant cohort). Demographic, clinical, and tumor characteristics were reviewed in breast cancer patients. The frequency of C282Y genotypes in breast cancers was compared with the frequency in nonbreast cancers, an outpatient sample from Tennessee (n = 169), and a published United States national sample. The frequency of at least one C282Y allele in breast cancers was higher (36.6%, 5 homozygotes/10 heterozygotes) than frequencies in Tennessee (12.7%, P < 0.001), the general population (12.4%, P < 0.001), and similarly selected nonbreast cancers (17.0%, P = 0.008). The likelihood of breast cancer in the transplant cohort increased with C282Y allele dose (P(trend) = 0.010). These results were supported by the finding in a nontransplant cohort of a higher frequency of C282Y mutations in Caucasian (18.4%, P = 0.039) and African-American (8.5%, P = 0.005) women with breast cancer than race-specific national frequency estimates. A high prevalence of C282Y alleles in women with breast cancer with and without poor risk features suggests that altered iron metabolism in C282Y carriers may promote the development of breast cancer and/or more aggressive forms of the disease. 相似文献
10.