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131.
We report on the spontaneous expression of fra(10)(q25) in bone marrow from a patient with agranulocytosis. Expression of this fragile site in both bone marrow and leukocytes was enhanced by bromodeoxyuridine (BrdU), while folic-acid-deficient medium enhanced the expression of fra(10)(q25) only in leukocytes. Variability in the expression of fra(10)(q25) in bone marrow and leukocyte cultures over an 18-month period was also found. 相似文献
132.
The acidosis of cholera. Contributions of hyperproteinemia, lactic acidemia, and hyperphosphatemia to an increased serum anion gap 总被引:4,自引:0,他引:4
To study the metabolic acidosis that occurs during the diarrhea of cholera, we examined the serum anion gap in 21 patients with hypovolemic shock due to Vibrio cholerae infection. Measurements of serum electrolytes, as well as divalent cations and the anionic contributions of serum proteins, lactate, phosphate, and serum creatinine, were made at the time of admission, after rehydration, and during convalescence. At the time of admission, the mean serum concentration of sodium was 134.8 mmol (meq) per liter, that of chloride was 103.2 mmol per liter, and that of bicarbonate was 11.4 mmol per liter; the mean anion gap was 20.2 mmol per liter. The mean serum creatinine concentration was 2.48 mg per deciliter. The low serum bicarbonate level and the high serum anion gap were corrected by rehydration. The increased serum anion gap was caused by hyperproteinemia, lactic acidemia, and hyperphosphatemia, with anionic contributions to the rise in anion gap estimated as protein, 5.5 meq per liter; lactate, 2.5 meq per liter; and phosphate, 2.5 meq per liter. The hyperproteinemia was attributed to dehydration, the lactic acidemia to shock, and the hyperphosphatemia to acidosis and transient renal failure. The mean concentrations of serum calcium and magnesium were slightly elevated but did not affect the increased anion gap. These results indicate that severe cholera causes acidosis with relatively little change in serum chloride but an increased serum anion gap. The acidosis is more profound than would be expected on the basis of stool losses of bicarbonate, because of superimposed lactic acidemia and renal failure. 相似文献
133.
Plachot Michelle; Junca Anne-Marie; Mandelbaum Jacqueline; Cohen Jean; Salat-Baroux Jacques; Lage C.Da 《Human reproduction (Oxford, England)》1986,1(4):237-242
In humans, in contrast to other species, sperm capacitationrequires a very short time, as in-vitro fertilization has beenobtained after only 45 mm of contact between oocytes and spermatozoacapacitated for 1 h. No fertilization occurred, whatever theduration of sperm capacit.ation, when gamete mixing did notexceed 30 mim. On the contrary, 85% of cumulus-free mature oocytesexposed to sperm for 14 h were fertilized. The presenceof the pre-ovulatory, fully-expanded or compact cumulus massdid not represent a physical barrier to sperm progression, aswe observed no delay in fertilization when oocytes were enclosedin the cumulus. The use of a short insemination protocol (14h instead of 1720 h) did not reduce the fertilizationrate of denuded or cumulus-enclosed oocytes and had no significanteffect on the morphological appearance of the embryos or theircleavage rates. 相似文献
134.
M E Cunninghame J G Evans W H Butler 《International journal of experimental pathology》1990,71(5):677-687
Mice were given a single dose of diethylnitrosamine (DEN). After 12 and 15 months, the ultrastructural features of simple hepatic nodules and defined hepatocellular carcinomas were compared. The main difference between these two lesions is the presence of highly convoluted membranes in the hepatocytes of the carcinomas. A third population of nodules was also found which could not be easily classified at the light microscope level into either simple hepatic nodules or carcinomas. Ultrastructural examination of these lesions showed them to have areas resembling both simple hepatic nodules and carcinomas. Within both these areas hepatocytes with convoluted plasma membranes were observed. Changes in membrane pattern may be indicative of an altered cell growth pattern and the acquisition of invasive or metastatic properties. This provides further evidence suggesting that a sub-population of cells can be identified which has the potential to develop into overt carcinoma. 相似文献
135.
Description of the transcriptomes of immune response-activated hemocytes from the mosquito vectors Aedes aegypti and Armigeres subalbatus 总被引:3,自引:0,他引:3
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136.
Lu W Parikh PJ El Naqa IM Nystrom MM Hubenschmidt JP Wahab SH Mutic S Singh AK Christensen GE Bradley JD Low DA 《Medical physics》2005,32(4):890-901
We have developed a four-dimensional computed tomography (4D CT) technique for mapping breathing motion in radiotherapy treatment planning. A multislice CT scanner (1.5 mm slices) operated in ciné mode was used to acquire 12 contiguous slices in each couch position for 15 consecutive scans (0.5 s rotation, 0.25 s between scans) while the patient underwent simultaneous quantitative spirometry measurements to provide a sorting metric. The spirometry-sorted scans were used to reconstruct a 4D data set. A critical factor for 4D CT is quantifying the reconstructed data set quality which we measure by correlating the metric used relative to internal-object motion. For this study, the internal air content within the lung was used as a surrogate for internal motion measurements. Thresholding and image morphological operations were applied to delineate the air-containing tissues (lungs, trachea) from each CT slice. The Hounsfield values were converted to the internal air content (V). The relationship between the air content and spirometer-measured tidal volume (v) was found to be quite linear throughout the lungs and was used to estimate the overall accuracy and precision of tidal volume-sorted 4D CT. Inspection of the CT-scan air content as a function of tidal volume showed excellent correlations (typically r>0.99) throughout the lung volume. Because of the discovered linear relationship, the ratio of internal air content to tidal volume was indicative of the fraction of air change in each couch position. Theoretically, due to air density differences within the lung and in room, the sum of these ratios would equal 1.11. For 12 patients, the mean value was 1.08 +/- 0.06, indicating the high quality of spirometry-based image sorting. The residual of a first-order fit between v and V was used to estimate the process precision. For all patients, the precision was better than 8%, with a mean value of 5.1% +/- 1.9%. This quantitative analysis highlights the value of using spirometry as the metric in sorting CT scans. The 4D reconstruction provides the CT data required to measure the three-dimensional trajectory of tumor and lung tissue during free breathing. 相似文献
137.
Uptake of host cell transforming growth factor-beta by Trypanosoma cruzi amastigotes in cardiomyocytes: potential role in parasite cycle completion
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138.
Automated DNA fingerprinting analysis of Mycobacterium tuberculosis using fluorescent detection of PCR products. 总被引:2,自引:2,他引:2
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DNA fingerprints of Mycobacterium tuberculosis are produced by restriction fragment length polymorphism analysis of the insertion element IS6110. We modified a PCR-based subtyping method, mixed-linker PCR with fluorescent-labeled IS6110-specific oligonucleotides, to demonstrate rapid, automated, and unattended electrophoretic analysis. Variation in band sizing (normally occurring with fragment mobility), an artifact of lane-to-lane and gel-to-gel differences, was controlled with an internal lane standard, resulting in accurate and precise DNA sizing. By using this method, fingerprint analysis can be performed using actual fragment length rather than estimated position analysis. 相似文献
139.
Michelle K Williamson Jane Pirkis Jon J Pfaff Orla Tyson Moira Sim Ngaire Kerse Nicola T Lautenschlager Nigel P Stocks Osvaldo P Almeida 《BMC medical research methodology》2007,7(1):42
Background
Recruiting and retaining GPs for research can prove difficult, and may result in sub-optimal patient participation where GPs are required to recruit patients. Low participation rates may affect the validity of research. 相似文献140.
Pooling of clinical specimens prior to testing for Chlamydia trachomatis by PCR is accurate and cost saving
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Currie MJ McNiven M Yee T Schiemer U Bowden FJ 《Journal of clinical microbiology》2004,42(10):4866-4867
The accuracy and cost savings of pooling specimens prior to testing for Chlamydia trachomatis by PCR were evaluated with genital and urine specimens (n = 2,600). There was a 60% reduction in tests without significant loss of accuracy. The efficiency of pooling vaginal swabs is demonstrated for the first time. 相似文献