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The first step of enzyme linked immunosorbent assay (ELISA), namely, adsorption of antigen or antibody to the plastic microtiter well plate, was studied as a function of insolubility of IgG in water. Immobilization efficiency was assessed in terms of number of wells coated per milliliter of primary antiserum. We have compared different coating/immobilization protocols, i.e., direct and indirect immobilization of primary antibody to the plastic microtiter well plate using carbonate buffer and phosphate buffer with glutaraldehyde. We have observed efficient coating when the immobilization of primary antibody through an immunobridge technique was performed, where water was used as a coating medium. It gave a higher number of wells coated per milliliter of anti-serum (primary or secondary) than other compared coating protocols and it allowed the use of serum (non-immune) and anti-serum (primary and secondary antibody) dilutions, avoiding the need for gamma-globulin purification from normal and immunized serum.  相似文献   
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Background  

Colon cancer is the second leading cause of cancer deaths in the western world. If detected early, colorectal cancer is one of the most treatable forms of cancer. Unfortunately, very few people are screened. N-myristoyltransferase (NMT) catalyzes myristoylation of various proteins including oncoproteins. We have demonstrated earlier the alteration of NMT activity during the progression of colorectal cancer and established NMT as a putative therapeutic target for cancer.  相似文献   
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Hereditary hearing impairment affects about 1 in 1000 newborns. In most cases hearing loss is non-syndromic with no other clinical features, while in other families deafness is associated with specific clinical abnormalities. Analysis of large families with non-syndromic and syndromic deafness have been used to identify genes or gene locations that cause hearing impairment. The present report describes a large Norwegian family with autosomal dominant non-syndromic, progressive high tone hearing loss with linkage to 1q21-q23. A maximum LOD score of 7.65 (theta = 0.00) was obtained with the microsatellite marker D1S196. Analysis of recombinant individuals maps the deafness gene (DFNA7) to a 22 cM region between D1S104 and D1S466. The region contains several attractive candidate genes. This report supports the idea of extensive genetic heterogeneity in hereditary hearing impairment and represents the first localization of a deafness gene in a Norwegian family.   相似文献   
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Sixteen patients with suspected cerebral metastases were studied with magnetic resonance (MR) imaging before and after the intravenous administration of 0.1 mmol/kg of gadolinium diethylenetriaminepenta-acetic acid. The images were interpreted blindly by two neuroradiologists; all clinical, radiologic (computed tomographic and MR imaging), and pathologic data were reviewed to arrive at a final "best diagnosis," which was then compared with the prior blinded interpretations. Of seven patients found to have multiple metastases, six (86%) had at least one tumor nodule depicted by postinfusion MR imaging that was missed by one or both observers on review of preinfusion images alone. Lesions missed on preinfusion studies were usually small nodules hidden by or not detected next to regions of high-signal edema thought to be related to the adjacent tumor nodule. The authors believe that contrast enhancement improves detection of metastatic foci with MR imaging and that the findings indicate broader implications for the detection of multiple lesions from other causes.  相似文献   
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A population based hybrid design combining element of cohort and cross-sectional approach was used to develop a simple clinical algorithm to predict individual probability of developing hypertension (systolic BP > 140 mm Hg and/or diastolic BP > 90 mmHg). 3615 soldiers initially normotensive at the time of induction into high altitude, were studied by systematic random sampling. Multiple logistic regression analysis showed a high significant association between hypertension and age, body mass index (BMI), tobacco smoking and alcohol consumption. Using the constant/coefficient values obtained from the logistic model and the receiver operating characteristics (ROC) curve analysis, the following predictive rule was developed – To the age in years, add (BMIx 3.86); also add 5.53 if he is a smoker; and add 19.81 if he consumes alcohol. If the total exceeds 142, the individual is at high risk of developing hypertension. This algorithm carries a sensitivity of 68.2% and specificity of 78.5%.KEY WORDS: Hypertension, High altitude  相似文献   
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Purpose

Antropylorus transposition in the perineum for end-stage anal incontinence has shown to be feasible in humans. Vascular anatomy of the antro-pyloro-duodenal area is critical in preventing complications and increasing pyloric graft survival. This study was undertaken to examine the vascular anatomy of antro-pyloro-duodenal area in an attempt to safeguard the graft blood supply and improve its survival.

Methods

After obtaining preoperative CT angiography to delineate the infrapyloric artery (IP a.), bench dissection of resected pancreaticoduodenectomy specimens was performed in 12 patients. Ex vivo angiography of these specimens were also performed. Subsequent to the information obtained from these dissections, the method of antropylorus mobilization during transposition was modified in terms of the site of division of the right gastroepiploic a. (Rt GEA). Perioperative outcomes (graft related complications, fecal incontinence scores, Doppler flow studies, and manometry studies of the graft) were compared between the two groups.

Results

IP a. originated only from the Rt GEA in 8 cases (66 %) and from both the gastroduodenal a. and the Rt GEA in the rest. However, its origin solely from the gastroduodenal a. was not observed. The pyloric graft survival, pyloric valve pressures and Doppler flow velocities were significantly (p < 0.05) better when the infrapyloric a. was preserved following this refinement. However, no immediate significant difference in incontinence scores was observed.

Conclusions

Careful preservation of the pyloric valve vascularity by preserving the IP a. by dividing the Rt GEA at its origin increases vascularity, survival and contractility of the pyloric graft in perineum.  相似文献   
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