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This report describes experience with radiation therapy in hyperbaric oxygen in 201 patients with squamous carcinoma arising in the mobile portion of tongue (anterior 2/3), oropharynx, hypopharynx, and supraglottic larynx, treated between the years 1964 and 1980. Although not statistically different, the overall 5-year determinate survival figures of 35% for all patients with tumors arising in the hypopharynx, 87.5% for Stage I and II, 55% for Stage III, and 27.1% for Stage IV supraglottic carcinoma were perceptibly better than those obtained in a contemporary but not randomly controlled series of patients treated in air at Royal Adelaide Hospital from 1970 to 1980. The results obtained for tumors arising in the oropharynx and mobile portion of tongue however were found to be very similar to those achieved in air. The results achieved in this series are discussed in the context of experience at other centers and the role of randomly controlled clinical studies in evaluating new treatment modalities is emphasized.  相似文献   
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L. G. is a 37-year-old black female, first seen in the Nephrology Clinic in May 1987 with a serum creatinine of 3.7 mg/dl. Ultrasound studies revealed bilaterally contracted kidneys. Over the next 18 months, the patient's renal function continued to deteriorate and she was started on hemodialysis. She stayed on hemodialysis for about one year but finally changed to continuous ambulatory peritoneal dialysis (CAPD) because of multiple vascular access problems. Over the next two and a half years the patient did well on CAPD. Then on a routine breast self-examination, she discovered a firm, approximately 1.5 cm mass below the right nipple. A mammogram was done which revealed the lesion to be suspicious for malignancy. Biopsy of the lesion revealed a poorly differentiated mammary carcinoma. The patient subsequently underwent a right mastectomy without complication .
Past medical history includes cholecystectomy which was done about seven years previously, and an abnormal Tiberoxime Stress Test, but a normal coronary angiogram done as part of her renal transplant evaluation. About four years ago, the patient complained of swelling in the right breast. She was seen by a surgeon and had a mammogram performed which was normal. She had a follow-up mammogram in 1991 which was again normal .  相似文献   
104.

Background

Phaconit or ultra micro incision phacoemulsification cataract surgery involves phacoemulsification through a 0.9 millimetre sleeveless phaco tip and irrigating chopper followed by implantation of a rollable intraocular lens. The procedure leads to negligible astigmatism and faster visual recovery as compared to phacoemulsification with a foldable intraocular lens.

Methods

This prospective study analysed 80 cases of sub millimetre phaconit surgery with implantation of rollable intraocular lenses(IOL) in 40 cases and acrylic foldable IOL in the remaining 40 cases. Evaluation of efficacy and adaptability of procedure, equipment settings, operative constraints, postoperative complications, keratometric and topographic evaluation of induced astigmatism with visual outcome and patient''s rehabilitation were studied.

Results

The intraoperative complications were surge/ chamber collapse in 16 (20%), iris chaffing in one and corneal burns in two cases. All cases had an induced astigmatism of less than or equal to ± 0.25 D in four to six weeks after rollable IOL and ± 0.5 D to ± 0.75 D after acrylic IOL implantation. All patients had best-corrected visual acuity of 6/6 by third post operative day.

Conclusion

Phaconit with rollable IOL is a perfect blend of surgical skill, application of technology and ultra thin IOL.Key Words: Phaconit, Ultra micro phaco, Submillimetre incision, Rollable IOL implantation  相似文献   
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目的:间充质干细胞具有强大的增殖能力和多向分化潜能,文章对其主要的来源途径予以综述。资料来源:应用计算机检索Medline1991-01/2006-01期间的相关文章,检索词为“mesenchyma stem cells,origin,research progress”,并限定文章语言种类为English。同时计算机检索中国期刊全文数据库1998-01/2006-10期间的相关文章,检索词为“间充质干细胞,来源,研究进展”,并限定文章语言种类为中文。资料选择:对资料进行初审,并查看每篇文献后的引文。纳入标准:①间充质干细胞的起源。②间充质干细胞研究进展、干细胞的分离及鉴定。排除标准:重复研究、个案报告或Meta分析类文章。资料提炼:共收集到96篇相关文献,40篇文献符合纳入标准,排除的56篇文献为内容陈旧或重复。符合纳入标准的40篇文献中,分别涉及骨髓、肌肉、脐血、胎盘、外周血、脂肪组织、血管及其他来源的间充质干细胞。资料综合:间充质干细胞是属于中胚层的一类多能干细胞,具有强大的增殖能力和多向分化潜能,动物模型试验和临床应用研究也取得了一定的效果。间充质干细胞来源广泛,易于获得,临床上为神经损伤及其他系统的损伤修复提供了更为广泛的途径。结论:间充质干细胞主要来源于骨髓、肌肉、脐血、外周血、胎盘等组织,具有广阔的应用前景。  相似文献   
107.
Interleukin-8 (IL-8) is a chemoattractant cytokine involved in chemotaxis and activation of neutrophils. Because in vivo administration of IL-8 induces mobilization of hematopoietic stem cells in mice, we assessed the mobilizing properties of IL-8 in rhesus monkeys. Recombinant human IL-8 was administered as a single intravenous injection at doses of 10, 30, and 100 micrograms/kg to rhesus monkeys (age, 2 to 3 years; weight, 2.5 to 4.5 kg). Venous blood samples were obtained at time intervals ranging from 1 to 480 minutes after IL-8 administration. Cell counts, colony-forming unit-Mix assays, and fluorescence-activated cell sorter analysis were performed. Plasma was harvested to assess IL-8 levels. A time-controlled bolus intravenous injection of 100 micrograms IL-8 per kilogram of body weight resulted in peak IL-8 plasma levels up to 5 micrograms/mL. The calculated half-time life of free IL-8 was 9.9 +/- 2.2 minutes. IL-8 injection resulted in instant neutropenia that was due to pulmonary sequestration, as shown using 99mTc-labeled leukocytes. Within 30 minutes after IL-8 injection, neutrophilia developed with counts up to 10-fold greater than baseline levels. The numbers of hematopoietic progenitor cells (HPCs) increased from 45 +/- 48/mL to 1,382 +/- 599/mL of blood at 30 minutes after injection of 100 micrograms IL-8 per kilogram of bodyweight (mean +/- SD, n = 8). Individual animals showed 10- to 100-fold increase in numbers of circulating HPCs that returned to almost pretreatment values (92 +/- 52 CFU/mL) at 240 minutes after the injection of IL-8. Immunophenotyping showed no significant changes in lymphocyte (sub)populations. A second bolus injection of IL-8 with an interval of 72 hours resulted in similar numbers of mobilized stem cells as observed after the first injection, showing that no tachyphylaxis had occurred. We conclude that IL-8 induces mobilization of HPCs from the bone marrow of rhesus monkeys in a rapid and reproducible fashion. Therefore, IL-8 may be a potentially useful cytokine in the setting of blood stem cell transplantation.  相似文献   
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Effect of oncogenic virus on muscle differentiation.   总被引:23,自引:12,他引:23       下载免费PDF全文
Chick muscle cultures infected with wild-type Rous sarcoma virus form myotubes, but these myotubes vacuolate and by day 6 most have degenerated, leaving only large numbers of transformed mononucleated, replicating cells. Muscle cultures infected with a temperature-sensitive mutant (TS) at permissive temperatures behave as cells infected with wild-type Rous sarcoma virus. TS-infected cells reared for 8 days at nonpermissive temperature form contracting myotubes, plus large numbers of fibroblastic cells. If these cultures are lowered to permissive temperature, within 72 hr the myotubes vacuolate and degenerate, whereas the mononucleated cells transform. If replicating TS-transformed cells after 8 days at permissive temperature are shifted to nonpermissive temperature, within 72 hr many cells fuse and form contracting, post-mitotic myotubes. Creatine kinase (ATP:creatine N-phosphotransferase, EC 2.7.3.2) levels parallel the formation and degeneration of myotubes during these temperature shifts. If the viral transforming gene is expressed in the post-mitotic myotubes it is lethal, whereas it is not lethal if expressed in replicating percursor myogenic cells. The viral gene expression at permissive temperature blocks further myogenesis depending on the position of the cells in the myogenic program. The virus does not cancel the replicating, transformed myogenic cells' commitment to, or position in, the myogenic lineage. When the transforming action of the virus is suppressed, the normal myogenic program resumes.  相似文献   
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