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81.
Polymorphism of the h allele and the population frequency of sporadic nonfunctional alleles 总被引:2,自引:0,他引:2
BACKGROUND: Current polymerase chain reaction-based strategies for phenotype prediction often fail when sporadic nonfunctional alleles are encountered. The population frequency of such mutations was not known for any gene under low selection pressure and may be best examined in blood groups systems lacking prevalent nonfunctional alleles. The frequency of the very rare Bombay blood group (Oh, genotype hh sese) was recently determined in a systematic survey of more than 600,000 white individuals. STUDY DESIGN AND METHODS: With this survey used in conjunction with additional blood samples, the population frequency of nonfunctional alleles of the gene encoding the alpha (1,2)fucosyltransferase (H or FUT1) was determined. RESULTS: Seven different h alleles were found in five unrelated individuals, three of whom were homozygous for unique alleles. There was no prevalent h allele. Five missense and one frameshift mutations were observed, that were the presumptive causes of the null phenotype; the coding sequence of one h allele was identical to the H sequence. The average inbreeding factor alpha was 0.00116. The frequency of nonfunctional alleles at the H gene locus was calculated as 1 in 347 in a large white population (95% CI: 1:185-1:824). CONCLUSION: The Bombay blood group phenotype in white is due to diverse, sporadic, nonfunctional alleles without any prevalent allele. Assuming similar rates of nonfunctional alleles in glycosyltransferase genes like ABO, current genotyping strategies may fail as often as once in about 300 individuals of blood group O. Sporadic neutral alleles may also pose a serious obstacle for population-wide screening of many disease-associated genes. 相似文献
82.
S Balci B Onol M D Er?al S Beksa? C Erzen O Akhan 《The Turkish journal of pediatrics》1992,34(3):179-185
A case of Meckel Gruber syndrome is presented, diagnosed prenatally from the medical history of the mother which revealed a previous malformed stillborn with anencephaly, meningomyelocele, polydactyly and ambiguous genitalia. This was the first prenatally diagnosed case ever reported in Turkey. The clinical, computed tomography and postmortem findings and the related literature are reviewed. 相似文献
83.
本文用高效液相色谱法测定人血中普鲁卡因酰胺(PA)及其代谢产物N-乙酰普鲁卡因酰胺(NAPA)。以正丙醇—氯仿(1:9)提取血清样品,蒸干,残渣用流动相溶解;色谱分析条件:NOVA-PAK 5μm ODS柱,醋酸(40 ml)—醋酸钠(4g)—水(1000ml)—乙腈(100ml)为流动相;定量分析以普鲁卡因为内标,样品的比率色谱图表明分离良好,PA和NAPA的线性测定范围分别为0.5~12.0μg/ml和0.5~6.0μg/ml,相关系数均优于0.99,平均回收率分别为99.4%和100.5%,平均变异系数分别为4.16%和4.36%。方法适用于血清样品分析和治疗药物监测,对病人血样的测定结果表明方法不受干扰。 相似文献
84.
Epithelioid sarcoma is a rare soft-tissue sarcoma which classically presents as a subcutaneous or deep dermal mass in distal extremities of adolescents and young adults. A more aggressive "proximal" or "large-cell" type has been described in rare cases to occur as a deep soft-tissue mass at proximal body sites which tends to recur and metastasize earlier than the conventional epithelioid sarcoma. The correct diagnosis of this type is essential since these lesions can easily be misdiagnosed as other epithelioid lesions. Its prognostic factors also have not yet been fully investigated. We herein report a case of metastatic proximal-type epithelioid sarcoma arising from the scrotum of a 50-year-old man managed by radical surgery and adjuvant chemotherapy. 相似文献
85.
Rabbit IgG anti-chicken erythrocyte antibodies were compared with the Fab/c or Facb fragments of IgG and with partially reduced and alkylated IgG for the capacity to induce cytotoxicity by normal human lymphocytes. The Fab/c antibody fragment, which lacks one Fab region, was still able to induce cytotoxicity. In contrast, the Facb antibody fragment, which lacks the Cγ3 domains, was nearly ineffective in activating the effector cells, whereas intact antibody activity was demonstrated by its ability to inhibit the cytotoxicity induced by unsplit IgG. Similarly, partial reduction and alkylation of the IgG antibodies, under conditions affecting the interchain disulphide bonds only, greatly diminished their ability to induce cytotoxicity, although they effectively inhibited the cytotoxicity induced by untreated IgG. On the basis of these results and previous data, we suggest that the reaction of the Fc region of IgG with the effector cell depends on the integrity of the Cγ2 domain in the native, divalent state or on the interaction between the Cγ2 and Cγ3 domains. 相似文献
86.
Haliloğlu G Vezir E Baydar L Onol S Sivri S Coşkun T Topçu M 《The Turkish journal of pediatrics》2012,54(1):52-58
Neurometabolic diseases diagnosed by cerebrospinal fluid (CSF) examination are GLUT1 deficiency, serine-deficiency syndromes, glycine encephalopathy, cerebral folate deficiency, neonatal vitamin-responsive epileptic encephalopathies, disorders of monoamine metabolism, and y-amino butyric acid (GABA) metabolism. We retrospectively analyzed and compared the demographic, clinical, laboratory, and neuroimaging features of 62 patients in whom CSF examination was performed. Of the 62 patients, 16 (25.8%) had a final diagnosis, including succinic semialdehyde dehydrogenase (SSADH) deficiency (n=4), aromatic amino acid decarboxylase (AADC) deficiency (n=4), L-dopa-responsive dystonia (n=3), glycine encephalopathy (n=2), pyridoxal-phosphate-dependent seizures (n=l), cerebral folate deficiency (n=1), and serine biosynthesi defect (n=1). Parental consanguinity was present in all patients except one Positive yield of a diagnostic lumbar puncture (LP) for the diagnosis of inherited neurotransmitter metabolism disorder was 25.8% overall. Oculogyric crisis (50%), diurnal variation (81.8%) and consanguinity (93.8%) were the only statistically significant variables between patients with and without a specific diagnosis. It is challenging to diagnose neurotransmitter defects, since there is no ideal set of clinical symptoms. In our cohort, consanguinity, diurnal variation and abnormal ocular movements were the most significant findings associated with a diagnosis of a specific neurometabolic disorder based on CSF examination. Early diagnosis is of great importance not only for specific treatment, but also for genetic counseling and prenatal diagnosis. 相似文献
87.
In this study, 24 patients aged 70 and over who were operated for primary bronchogenic carcinoma were reviewed retrospectively and their results were compared with those of 90 patients under 70, whom operated for the same intent. The mean age and age range of the group were 74.6 +/- 3.3 and 70-86, respectively, and it consisted of 21 male and three female patients. The histology of the tumor revealed epidermoid carcinoma in 16 (67%) patients, adenocarcinoma in 6 (25%), and large cell carcinoma in 2 (8%). Twelve of the elderly patients had associated diseases (six had coronary artery disease and/or hypertension, four had chronic obstructive pulmonary disease and two had diabetes) that increased the operative risk. The resection type used most frequently was lobectomy (67%), followed by limited resection (25%). In postoperative staging, nine patients were found to have stage I disease, nine stage II disease, four stage IIIA disease and two stage IIIB disease. Three (13%) patients developed major complications, and postoperative mortality rate within 30 days was 4% with one patient. In the patients aged under 70, the last two variables were noted in 10 (%11) cases and in 1 (%1) case respectively, and the difference between the two groups was statistically insignificant. As a result, with appropriate patient selection and vigorous postoperative care, morbidity and mortality of the pulmonary resections in elderly is not higher than in young patients, and a curative resection should be preferred. 相似文献
88.
Alidianne?Fábia?C?XavierEmail author Eline?FF?Moura Waldeneide?F?Azevedo Fernando?F?Vieira Mauro?HNG?Abreu Alessandro?L?Cavalcanti 《BMC oral health》2013,13(1):71
Background
Pediatric medications may possess a high erosive potential to dental tissues due to the existence of acid components in their formulations. The purpose was to determine the erosive and cariogenic potential of pediatric oral liquid medications through the analysis of their physicochemical properties in vitro.Methods
A total of 59 substances were selected from the drug reference list of the National Health Surveillance Agency (ANVISA), which belong to 11 therapeutic classes, as follows: analgesics, non-steroidal anti-inflammatory, corticosteroids, antihistamines, antitussives, bronchodilators, antibacterials, antiparasitics, antiemetics, anticonvulsants and antipsychotics. Measurement of pH was performed by potentiometry, using a digital pH meter. For the Total Titratable Acidity (TTA) chemical assay, a 0.1 N NaOH standard solution was used, which was titrated until drug pH was neutralized. The Total Soluble Solids Contents (TSSC) quantification was carried out by refractometry using Brix scale and the analysis of Total Sugar Content was performed according to Fehling’s method. In addition, it was analyzed the information contained in the drug inserts with regard to the presence of sucrose and type of acid and sweetener added to the formulations.Results
All drug classes showed acidic pH, and the lowest mean was found for antipsychotics (2.61?±?0.08). There was a large variation in the TTA (0.1% - 1.18%) and SST (10.44% - 57.08%) values. High total sugar contents were identified in the antitussives (53.25%) and anticonvulsants (51.75%). As described in the drug inserts, sucrose was added in 47.5% of the formulations, as well as citric acid (39.0%), sodium saccharin (36.4%) and sorbitol (34.8%).Conclusion
The drugs analyzed herein showed physicochemical characteristics indicative of a cariogenic and erosive potential on dental tissues. Competent bodies’ strategies should be implemented in order to broaden the knowledge of health professionals, drug manufacturers and general consuming public about the risks from the consumption of medicines potentially harmful to dental tissues.89.
90.
High glucocorticoid receptor content of leukemic blasts is a favorable prognostic factor in childhood acute lymphoblastic leukemia 总被引:4,自引:1,他引:4
Kato GJ; Quddus FF; Shuster JJ; Boyett J; Pullen JD; Borowitz MJ; Whitehead VM; Crist WM; Leventhal BG 《Blood》1993,82(8):2304-2309
We have previously shown that the number of glucocorticoid receptors (GR) per cell in malignant lymphoblasts from children with newly diagnosed pre-B- and early pre-B-cell acute lymphoblastic leukemia (ALL) has a positive correlation with the probability of successful remission induction (Quddus et al, Cancer Res, 45:6482, 1985). We report now on the long-term outcome for these patients treated on a single protocol with 3 different treatment arms, all of which included glucocorticoid pulses during maintenance therapy. GR were quantitated in leukemic cells from 546 children with ALL at the time of diagnosis. Immunophenotyping studies were performed on all specimens. Prior studies showed that in pre-B- and early pre-B-cell ALL, successful remission induction was associated with a median GR number of 9,900 sites/cell, whereas induction failure was associated with a median receptor number of 4,800 sites/cell. Long-term follow-up of these patients shows an association between higher GR number and improved prognosis. The 5-year event-free survival of 61.0% (SE 2.8%) for patients whose leukemic cells had greater than 8,000 receptors/cell and 47.3% (SE 3.3%) for those with less than 8,000 receptors/cell is significantly different (P < .001). This difference remains significant when adjusted multivariately for blast immunophenotype and clinical risk factors (P < .001) or for treatment type (P < .001). We conclude that GR number greater than 8,000 sites/leukemic cell is a favorable prognostic marker for children with acute lymphocytic leukemia. This finding offers deeper insights into molecular mechanisms of anti- leukemia therapy and suggests that manipulation of steroid receptor number might augment the antitumor response, thus opening new avenues for basic and clinical research. 相似文献