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81.
82.
Near-haploidy is a rare cytogenetic finding in childhood acute lymphoblastic leukaemia (ALL) and is associated with a poor prognosis. A second hyperdiploid line, occurring presumably by endoreduplication of the near-haploid stemline, is often observed. We present a case of common ALL in relapse characterized morphologically by a dual population of small and large lymphoblasts. Cytogenetic analysis supplemented with fluorescence in-situ hybridization (FISH) studies localized near-haploidy and hyperdiploidy to the small and large blast population respectively. DNA ploidy determination confirmed two abnormal clones with near-haploidy as the predominant one. A novel t(9;12)(q11;q13) was present in the near-haploid clone and was duplicated in the hyperdiploid clone. This finding identified cells bearing near-haploidy to be the clonogenic population following malignant transformation and confirmed endoreduplication as the mechanism for the presence of associated hyperdiploidy.  相似文献   
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We currently recommend excision of adrenal incidentalomas > or = 4 cm in size and all hormonally active tumors. The optimal management and follow-up of smaller nonfunctioning tumors are controversial. The aim of this study was to determine the clinical outcome of a well defined population of patients with incidentalomas followed without operative intervention. The study group comprised 231 patients, identified from the records of abdominal or thoracic computed tomographic (CT) scans performed between 1985 and 1989. The primary outcome variable analyzed was survival. Follow-up was obtained by office records, telephone contact, or letter. There were 101 male and 130 female patients with a mean age at diagnosis of 64 years (range 5-86 years). Most adrenal tumors were unilateral (right 113; left 98); 20 were bilateral. Mean tumor size was 2 cm (range 1-6 cm). In nine (4%) patients the tumor was > or = 4 cm. Follow-up [mean 7 years; range 1 month (patient died) to 11.7 years] was complete in 224 (97%) patients. Ninety-one (39%) patients had one or more additional CT scans performed during the follow-up period, with only four patients demonstrating a > 1 cm increase in the size of the adrenal mass. Surgical excision of these four lesions identified benign pathology. Eighty-one (35%) patients died of conditions unrelated to adrenal pathology. No patient developed subsequent adrenal hyperfunction or adrenal malignancy. Within the context of our guidelines, conservative management of adrenal incidentalomas considered benign or nonfunctioning at diagnosis is appropriate. Additional information provided by repeat CT scanning appears to confer limited benefit. This study does not support laparoscopic removal of small, nonfunctional adrenal tumors, as has been suggested.  相似文献   
85.
Strategies to noninvasively evaluate patients after coronary stenting have not been evaluated. To determine the accuracy of single-photon emission computed tomography (SPECT) myocardial perfusion imaging in patients after coronary stenting, 209 patients who had undergone stenting followed by late stress SPECT myocardial perfusion imaging were evaluated. Quantitative coronary angiography was performed in 33 patients following SPECT imaging. SPECT restenosis was defined as a reversible or fixed defect within the stented vascular territory. Angiographic restenosis was examined using 2 definitions: total area narrowing > or =50% or > or =70% of the stent site or stented artery. The SPECT and angiographic findings were concordant in 22 of 33 stented vascular territories using the 50% definition of restenosis and in 29 of 33 stented territories using the 70% definition. Use of the 70% definition of restenosis resulted in improved accuracy of SPECT to detect a significant stenosis in the stented artery. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of SPECT were 95%, 73%, 88%, 89%, and 88% respectively. In patients with positive SPECT scans, the most significant stenosis in the stented artery was outside the stent site in 50% of cases. SPECT imaging appears to be accurate to predict significant stenosis in the stented artery, although the most severe stenosis is frequently distant from the stent site.  相似文献   
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BACKGROUND: Chylothorax is a rare primary or secondary condition the optimum management of which remains uncertain. METHODS: Twenty cases of chylothorax, including ten of primary chylothorax and ten secondary to either malignancy, subclavian vein thrombosis or lymphangioma treated between 1956 and 1986 have been reviewed. RESULTS: Open pleurectomy was the most successful treatment in preventing reaccumulation of the effusion. Three patients had thoracic duct-azygous vein anastomoses, but all anastomoses were probably occluded within a year of surgery. Three patients have been lost to follow-up and five died within 2 years of their treatment, but 12 patients were alive and free from an effusion 3-22 years after treatment. CONCLUSION: Patients with chylothorax should undergo lymphangiography to identify the cause and site of the lymphatic abnormality. Conservative treatment is successful in some patients but should be abandoned if the fluid loss exceeds 1.5 l/day for more than 5-7 days in an adult or more than 100 ml/day in a child. Parietal pleurectomy is the most successful treatment when no distinct chylous leak can be identified. Less commonly, an isolated chylous leak either in the chest or in the abdomen may be identified and this should be treated by direct ligation.  相似文献   
89.
Follicles > or = 5 mm were ablated in pony mares by a transvaginal ultrasound-guided technique on Day 10 (ovulation = Day 0). Follicle emergence (at 15 mm, experiment 1; at 6 mm, experiment 2) and development of the new wave was monitored by transrectal ultrasound. Deviation was defined as the beginning of a marked difference in growth rates between the two largest follicles. In experiment 1, mares were grouped (n = 4 per group) into controls, ablation-controls (ablations at Day 10 only), and a two-follicle model (periodic ablation sessions so that only the two largest follicles developed). There were no significant indications that the two-follicle model altered follicle diameters, growth rates, or time intervals of the two retained follicles at or between events (follicle emergence, deviation, and ovulation). In experiment 2, the two-follicle model (n = 14) was used for follicle and hormonal characterization and hypothesis testing, without the tedious and error-prone necessity for tracking many (e.g., 20) individual follicles. The future dominant follicle emerged a mean of 1 day earlier (p < 0.008) than the future subordinate follicle, the growth rates for the two follicles between emergence and deviation (6 days later) did not differ, and the dominant follicle was larger at the beginning of deviation (23.1 +/- 0.8 mm versus 19.6 +/- 0.9 mm; p < 0.0001). Mean FSH and LH concentrations increased (p < 0.05) concomitantly from emergence of the future dominant follicle and peaked 3 days later when the follicle was a mean of 13 mm. Thereafter, the two hormones disassociated until ovulation: FSH decreased and LH increased. Results supported the hypothesis that the future dominant follicle has an early size advantage over future subordinate follicles and indicated that the advantage was present as early as 6 days before deviation.  相似文献   
90.
The objective of this study was to evaluate the effect of cannabidiol (CBD) on the crystallization behavior and physical properties of various fats. Anhydrous milk fat (AMF), palm oil (PO), palm kernel oil (PKO), and cocoa butter (CB) were chosen for this study, for their unique crystallization behaviors. CBD was added at 1 and 2.5% wt/wt to these fats, and the crystallization behavior was evaluated at 26°C for AMF and PO and at 22°C for PKO and CB. Control samples with no CBD were prepared and evaluated as well. Results show that CBD delayed the crystallization of all fats with the least effect observed for the PO. Slight increases in crystal size were observed with the addition of CBD for all samples. CBD did not affect the melting profile of AMF or CB, but it increased the peak temperature of PO and decreased the enthalpy of PKO. Similarly, hardness was only affected by CBD in PO samples, with harder materials obtained for samples containing 2.5% CBD. The same trend was observed for elasticity. In addition, the elasticity of AMF increased with the addition of CBD but not its hardness. Overall, this study indicates that the effect of CBD on fat crystallization is highly dependent on the type of fat used. Producers of fat-based products that are willing to include CBD in their formulations must carefully control processing conditions to ensure product quality.  相似文献   
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