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21.
224 patients with a recent diagnosis of chronic lymphocytic leukemia, confirmed by immune phenotype, were studied with a mean follow-up of 16 months. The median age was 72 years and the ratio of men to women was 1.51. An incidental diagnosis because of leukocytosis was made in 75% of the patients; in only 22% was the diagnosis related to symptoms. 80% were in stage A, 7.5% in stage B, and 12.5% in stage C. A relation was found between advanced stage and the number of lymphocytes in the blood, the percentage of lymphocytes in the bone marrow, WHO performance status, bacterial infection and disease-related mortality. Thus, six patients in stage C (21%) died because of infection (septicaemia or pneumonia), as opposed to only one out of 196 patients in stages A and B. The incidence of bacterial infection was 64% in stage C, as compared to 8.3% in stage A. Treatment with chlorambucil, started in 59 patients, was in accordance with the guidelines of the national programme for 52 of them. In contrast, a strict indication for prednisone (autoimmune cytopenia) was found in only 42% of 42 patients given this treatment. 相似文献
22.
IT Johnson 《Canadian Metallurgical Quarterly》1997,6(6):515-517
A patient with a 14q32.3 terminal band deletion and cat cry is reported. Review of four other 14q32.3 deletion cases suggests the possible presence of a recognisable 14q32.3 terminal deletion syndrome, which is characterised by (1) apparently postnatal onset of small head size in comparison to body size, (2) high forehead with lateral hypertrichosis, (3) epicanthic folds, (4) broad nasal bridge, (5) high arched palate, (6) single palmar crease, and (7) mild to moderate developmental delay. Although none of the above seven features in unique to this syndrome, and indeed are quite common in other chromosomal disorders or genetic syndromes, patients with a terminal 14q32.3 deletion do show a recognisable facial gestalt. Interestingly, unlike ring chromosome 14, the 14q32.3 terminal deletion has rarely been reported, possibly because it is harder to detect, and an optimal chromosome preparation is required for its identification. 相似文献
23.
Many procedures have been described to correct velopharyngeal incompetence. Significant complications can occur, and the results may not be satisfactory. If the short soft palate has satisfactory muscle function and if it could be moved toward the posterior pharyngeal wall by distraction osteogenesis of the hard palate, an entirely new concept of treatment for velopharyngeal incompetence would be available. The object of the present study was to explore the possibility of osteogenesis occurring in the hard palate in dogs after gradual distraction (callus distraction). Six adult, mix-bred dogs were anesthetized, and the palatal mucosa was elevated. A midpalatal transverse osteotomy and two lateral osteotomies were performed. Tantalum bone markers for cephalometric analysis were placed, and an individually fabricated, orthodontic-like distraction device with an expansion screw in the sagittal direction was inserted. The device was stabilized on the premolars and fixed to the palatal bone with titanium miniscrews. Gradual distraction began after a latency period of 10 to 18 days. The rate of the distraction varied from 0.25 to 0.75 mm per day. The device was left in place for 6 to 8 weeks after expansion to allow for bony consolidation. Assessment was by direct examination, cephalograms, computed tomography, and histology with bone labeling. Impressions of the jaws were taken preoperatively and after device removal to examine plaster cast changes in the dental occlusion. Cephalometric and computed tomographic scan analysis demonstrated a distraction of up to 8 mm. All gaps were filled with de novo osteogenesis. Comparison of the plaster casts revealed no change in the occlusion. At 1 month after distraction, the computed tomographic scan showed the first signs of ossification of the experimental gap from the anterior and posterior bone ends. After 4.5 months ossification was almost complete with a small translucent zone in the middle of the experimental gap. After 7 months ossification was complete. 相似文献
24.
IT Rubio Y Cao LF Hutchins KC Westbrook VS Klimberg 《Canadian Metallurgical Quarterly》1998,227(5):772-8; discussion 778-80
OBJECTIVE: To examine the effect of oral glutamine (GLN) on the efficacy and toxicity of methotrexate (MTX). SUMMARY BACKGROUND DATA: The use of high-dose chemotherapy regimens is limited by the severity of their toxicities. Oral GLN has been shown to decrease the gut toxicity seen with MTX treatment while enhancing its tumoricidal effect. METHODS AND RESULTS: Studies were done in laboratory rats and in breast cancer outpatients. Fischer 344 rats were randomized to 48 hours of prefeeding with GLN (1 g/kg/day) or an isonitrogenous amount of glycine. Rats were killed 24 hours after receiving a 20-mg/kg intraperitoneal dose of MTX. In the GLN group, there was a threefold increase in total MTX in the tumor as compared with the control group, and this increase was in both the diglutamated and pentaglutamated MTX. Inversely, there was a significant decrease in the total polyglutamated MTX in the gut in the GLN group. Given the results of this preclinical study, the authors performed a phase I trial. Nine patients diagnosed with inflammatory breast cancer received GLN (0.5 g/kg/day) during MTX neoadjuvant therapy, escalating from doses of 40 mg/m2 to 100 mg/m2 weekly for 3 weeks, followed by a doxorubicin-based regimen. No toxicity of oral GLN was detected. No patient showed any sign of chemotherapy-related toxicity. One patient had a grade I mucositis. Except for one, all patients responded to the chemotherapy regimen. Median survival was 35 months. CONCLUSIONS: These studies suggest that GLN supplementation is safe in its administration to the tumor-bearing host receiving MTX. By preferentially increasing tumor retention of MTX over that of normal host tissue, GLN may serve to increase the therapeutic window of this chemotherapeutic age. 相似文献
25.
26.
IT Jackson HY Choi R Clay R Bevilacqua S TerKonda M Celik AW Smith 《Canadian Metallurgical Quarterly》1998,102(6):1869-1873
A follow-up of 363 cranial bone grafts for nasal reconstruction is presented. The main indications for the surgery were congenital, posttraumatic, or postrhinoplasty deformity. The results were satisfactory in the vast majority of cases. The complications associated with the grafts and with the donor site are discussed, as are the methods to treat and prevent these complications from occurring. 相似文献
27.
Differentiation of biliary epithelial cells from hepatic endodermal cells of the mouse embryo was examined with a special attention to the role of the connective tissue. When the whole liver primordium of the 9.5-day mouse embryo was cultured in vitro for 5 days, the endodermal cells differentiated into mature hepatocytes expressing carbamoylphosphate synthetase I (CPSI) and accumulating glycogen. Intrahepatic bile duct cells and connective tissue were poorly developed in this culture. However, when the hepatic endoderm was recombined with the 4-day embryonic chick lung mesenchyme and cultured in vitro, the endodermal cells differentiated into many ductal epithelial cells as well as mature hepatocytes with abundant connective tissue development. These results suggest that the ducts might be bile ducts, and that connective tissue is very important for bile duct development. In addition, this in vitro culture system might be useful for the study of mechanisms of bile duct differentiation and congenital biliary atresia. 相似文献
28.
Metabolic engineering is defined as the purposeful modification of intermediary metabolism using recombinant DNA techniques. Cellular engineering, a more inclusive term, is defined as the purposeful modification of cell properties using the same techniques. Examples of cellular and metabolic engineering are divided into five categories: 1. Improved production of chemicals already produced by the host organism; 2. Extended substrate range for growth and product formation; 3. Addition of new catabolic activities for degradation of toxic chemicals; 4. Production of chemicals new to the host organism; and 5. Modification of cell properties. Over 100 examples of cellular and metabolic engineering are summarized. Several molecular biological, analytical chemistry, and mathematical and computational tools of relevance to cellular and metabolic engineering are reviewed. The importance of host selection and gene selection is emphasized. Finally, some future directions and emerging areas are presented. 相似文献
29.
It has been demonstrated that Adeturon (S-2-aminoethyl-iso-thiuronium adenosine triphosphate) showed a marked protective effect against translocations induction in mice germ cells after chronic gamma-or neutron-irradiation. 相似文献
30.
A 7-year-old girl twice developed severe hypernatremia (serum sodium values up to 194 mEq/l) without obvious cause. The ability of her kidneys to conserve water was normal, and increasing her plasma osmolality stimulated an appropriate ADH response. Unable to excrete a water load, her kidneys continued to conserve water even with a serum sodium concentration of 133 mEq/l. She was never thirsty and did not ingest sufficient fluid by choice. Although there was no demonstrable anatomic lesion, we postulate a localized defect of her thirst center. This may have modified release of ADH and resulted in an inability to dilute the urine by interrupting a pathway that could exist from the thirst center to the supraoptic nuclei. A therapeutic regimen based on these studies has prevented further hypernatremia. 相似文献