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11.
Eight laboratories in six countries cooperated to clarify several issues concerning the phenotypes of heterozygous carriers of hemophilia "A." Plasma levels of factor VIII (F.VIII:C, formerly VIII:C) and von Willebrand factor (VWF:Ag, formerly VIIIR:Ag) of carriers and normal women were determined by various "in-house" methods; a single lyophilized plasma standard was used for all assays. Analysis of the collated data from 336 carriers (296 obligatory carriers and 40 sporadic carriers) and 137 normal women showed that there was no difference in the F.VIII:C levels of "paternal" carriers (women who had obtained the abnormal gene from their fathers) and "maternal" carriers. Neither was there a difference in the VWF:Ag levels of normal women and either type of carrier. Age was found to have a significant effect on both F.VIII:C and VWF:Ag, values being higher at very young and very old ages, the minima occurring in the 25- to 30-year range. ABO blood type had a striking effect. Women of types A, B, and AB (designated non- O in the study), both normals and carriers, had significantly higher levels of both factors than did women of type O. Analysis by laboratories showed that differences in mean levels of both factors between laboratories were highly significant. It was concluded that age, ABO blood type, and laboratory variation should be taken into account in carrier detection.  相似文献   
12.
OBJECTIVE: Untreated hyperthyroidism and treatment with high doses of thyroid hormone are associated with osteoporosis. However, their effect on bone turnover, their contribution to bone mineral density (BMD) in the context of other clinical risk factors for osteoporosis and the prevalence of vertebral fractures is not well documented. DESIGN: Cross-sectional study. METHODS: We studied 59 patients receiving L-thyroxine suppressive therapy for differentiated thyroid carcinoma (DTC). BMD of the hip was measured by dual X-ray absorptiometry (DXA) and lateral DXA pictures of the lumbar and thoracic vertebrae were performed. Bone resorption was measured by C-telopeptides of type I collagen (ICTP) and bone formation by procollagen type I N-propeptide (PINP). Clinical risk factors for osteoporosis were evaluated using a questionnaire. RESULTS: Z-scores of BMD were similar as the NHANES (National Health and Nutrition Examination Survey) III reference group in women and men, also after long-term (> 10 years) suppression therapy. Patients in the lowest and highest quartile of BMD showed significant differences in the presence of clinical risk factors. ICTP levels were significantly higher than in age-matched controls, PINP levels were not different. We found four patients with a prevalent vertebral fracture. CONCLUSIONS: We conclude that patients with well-differentiated thyroid carcinoma are not at increased risk of developing low bone mass nor have a higher prevalence of vertebral fracture at least when treated with relatively low doses of L-thyroxine.  相似文献   
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The molecular characterization of the mutations in hemophilia A patients is hampered by the large size of the factor VIII gene and the great heterogeneity of mutations. In this study, we have performed a protocol involving multiplex polymerase chain reaction in which 19 exons were amplified in four different combinations followed by nonradioactive single-strand conformational polymorphism (SSCP) to screen for mutations. Southern blotting was used to detect inversion of the factor VIII gene resulting from recombination between copies of the gene A (F8A) located in intron 22 of the factor VIII gene and two copies close telomeric region of X chromosome. Forty-two hemophilia A patients (21 with severe and 21 with mild-to-moderate disease) were studied. The inversion of factor VIII occurred in 13 of 21 patients affected by severe hemophilia A. One patient showed a large extra band in addition to the three bands observed after Southern blotting with the F8A probe. An abnormal electrophoretic pattern of SSCP was detected in 85% and 50% of the patients affected by mild-to-moderate and severe disease, respectively. Sixteen different mutations were identified. Eleven mutations were novel and comprised 9 point mutations and 2 small deletions. This study shows that the methodology used is safe and rapid and has potential for detecting almost all of the genetic defects of the studied hemophilia A patients.  相似文献   
16.
We report 8 infants with immediate hypersensitivity reactions to foods (milk, egg, or peanut), occurring at the first-known exposure. Each developed symptoms within the first hour, but these generally settled within 2 hours. Sensitisation to the food concerned was demonstrated by positive immediate allergen skin prick tests in every case. Symptoms experienced included irritability, erythematous rash, urticaria, angio-oedema, vomiting, rhinorrhoea, and cough. Five infants were being followed prospectively and 4 were clinically tolerant of the food by age 16 months. The most likely route of sensitisation was via breast milk. None of the infants experienced similar reactions while being breast fed, suggesting that the reaction was dose dependent. As 5 out of a group of 80 infants being followed prospectively developed an immediate reaction at their first known exposure to a food, this appeared to be a not uncommon presentation of food hypersensitivity in infancy.  相似文献   
17.
OBJECTIVES: To identify parameters at first presentation after mild traumatic brain injury (MTBI) that are predictive of the severity of post-traumatic complaints (PTC) after six months. Early recognition of patients with MTBI who are at risk of developing PTC would be useful because early follow up at the outpatient clinic may help to reduce the severity of these complaints in the long run. METHODS: The presence of symptoms in the emergency room (ER) (headache, dizziness, nausea, vomiting, and neck pain) and biochemical markers (neurone specific enolase and S-100B) in serum were assessed as possible predictive variables for the severity of PTC. Outcome variables were the severity of 16 PTC six months after the trauma. RESULT: After six months, the severity of most complaints had declined to pretrauma levels but medians for headache, dizziness, and drowsiness were still increased. In a series of 79 patients, 22 (28%) reported one or more PTC after six months. After adjustment for baseline variables, an at least twofold increased severity of all PTC subgroups was reported by those patients reporting headache, dizziness, or nausea in the ER. A twofold increased severity of "cognitive" and "vegetative" PTC was also found in those with increased concentrations of biochemical serum markers at first presentation. The prevalence of full recovery after six months increased from 50% in patients with three symptoms to 78% in those with no symptoms in the ER. Inclusion of biochemical markers showed that all 10 patients with no symptoms in the ER and normal markers recovered fully. CONCLUSIONS: The presence of headache, dizziness, or nausea in the ER after MTBI is strongly associated with the severity of most PTC after six months. Identifying MTBI patients in the ER without headache, dizziness, nausea, or increased serum marker concentrations may be a promising strategy for predicting a good outcome.  相似文献   
18.
Decreased plasma orexin-A levels in obese individuals   总被引:10,自引:0,他引:10  
Orexin-A and -B stimulate appetite and food intake in rats. Orexins and orexin receptors are present in the hypothalamus as well as the enteric nervous system, the pancreas and the gut. The presence of orexins in peripheral blood, however, has not yet been reported. To determine whether orexin-A is present in human plasma and is related to body weight, we measured plasma orexin-A and leptin levels in a population with a body mass index (BMI) range from 19.8 to 59 kg/m(2). Plasma orexin-A levels correlated negatively and plasma leptin levels correlated positively with BMI. In obese and morbidly obese individuals, orexin-A levels were significantly lower and leptin levels were significantly higher when compared to normal. Our results support previous data suggesting that orexin-A acts also in a peripheral manner. The fact that lower levels of plasma orexin-A are present in obese individuals suggests that it is involved in the regulation of human energy metabolism.  相似文献   
19.
In a combined (cross-sectional and longitudinal) study, the serum concentration of laminin P1 was measured by radioimmunoassay in 16 patients with benign inflammatory bladder disorders and 47 patients with transitional cell carcinoma of the bladder. The results were compared with the serum laminin P1 values in 50 healthy control subjects. In the cross-sectional study, the mean value of serum laminin P1 was significantly higher in bladder cancer patients than either the controls (p < 0.0001) or patients with benign inflammatory bladder disorders (p < 0.001). Similarly, the mean values of all different stages of grades of the tumor were significantly higher than either the controls or patients with benign inflammatory disorders. Progressive increase in the mean values of serum laminin P1 could also be found with deterioration of the stage or grade of the tumor. However, the difference between the mean values of the different cancer stages or grades did not reach statistical significance. In the longitudinal study, no significant difference could be detected between the mean values of patients with superficial tumor recurrence and those with remission of the disease (p > 0.5). Nevertheless, in the invasive cancer group, the levels of serum laminin P1 were directly proportional with progression of the disease (Z = 2.94; p < 0.01).  相似文献   
20.

Background

HBV DNA quantitation is used extensively world wide for the diagnosis and monitoring of treatment of Hepatitis B virus (HBV) infection. However, it has still to be popular in India. The aim of this study was to quantitate HBV – DNA by Real time – PCR method in Hepatitis B and in immuno-compromised patients, to compare the results with HBeAg detection and to monitor the response to therapy of chronic Hepatitis B patients to antivirals.

Methods

Ninety one serum samples of Hepatitis group of patients (all HBsAg positive), 41 samples from immuno-compromised patients (all HBsAg negative) and 49 patients of Chronic Hepatitis B group (all HBsAg positive) were the subjects of this first ever study in Armed Forces. Twenty serum samples from healthy volunteers and non-hepatitis B patients served as negative controls. The amplification detection was carried out in a Rotor-Gene 2000-sequence detector

Results

Amongst Hepatitis B group, 33% (30/91) of the samples were positive for HBV-DNA and 26% (24/91) of samples were positive for HBeAg. In the immuno-compromised group of patients 14.6% (6/11) of samples were positive for HIV-DNA and 9.7% (4/41) were positive for HBeAg. Of the Chronic Hepatitis B patients on treatment, all (100%) were positive by HBV-DNA, whereas 29/49 (59.2%) were positive by HBeAg before treatment. After treatment with antivirals, 06/49 (12.2%) were positive by both tests and 11/49 (22.5%) were positive only by HBV-DNA. 32/49 (65.3%) patients became negative serologically after therapy.

Conclusion

HBeAg status did not necessarily reflect HBV-DNA level in the serum, as 10/91 (11%) in the Hepatitis B group, 2/41 (4.9%) in the immuno compromised group and 20/49 (40.8%) patients in the Chronic Hepatitis B group were positive for HBV-DNA but negative for HBeAg. HBV-DNA was not found to be positive amongst any of the negative controls. Real time – PCR is a sensitive and reproducible assay for HBV-DNA quantitation and may be started in Armed Forces referral centers in the near future.Key Words: Real time – PCR, Chronic Hepatitis B, HBV – DNA, Antivirals  相似文献   
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