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81.
A case of sclerosing epithelioid fibrosarcoma and its appearance on MRI is presented. The tumor showed a zonal architecture
on MRI with a large central core of very low signal intensity and a peripheral rim of intermediate to high signal intensity
on T1- and T2-weighted spin echo pulse sequences. The core showed decreased cellularity with dense collagen deposition on
histologic examination, and the peripheral zone increased cellularity with increased nuclear atypia. The presence of a prominent
region of very low signal intensity on T1- and T2-weighted images can be seen with neural tumors, giant cell tumor of the
tendon sheath, aggressive fibromatosis, and, in rare instances, with soft tissue sarcomas rich in collagen. 相似文献
82.
Bruce G. Haffty M.D. Peter L. Perrotta M.D. † Barbara Ward M.D. ‡ Meena Moran M.D. Malcolm Beinfield M.D. ‡ Charles McKhann M.D. ‡ Diana Fischer Ph.D. Darryl Carter M.D. † 《The breast journal》1997,3(1):7-14
Abstract: Between 1970 and 1990, 1,008 patients with early-stage breast cancer were treated by conservative surgery without axillary dissection followed by radiation therapy to the intact breast in the Department of Therapeutic Radiology at Yale-New Haven Hospital. The patient population, broken down by histologic subtype, was as follows: 761 patients presented with infiltrating ductal carcinoma, 70 patients with pure intraductal, 38 intraductal with focal invasion, 54 infiltrating lobular, 21 tubular, 17 medullary, 16 mucinous, and 29 with other various histologic subtypes. Patients were followed on a regular basis by the referring physicians and radiation oncologists. Diagnostic studies for distant metastases were performed as clinically indicated. Annual mammography was a routine component of the follow-up program. As of 3/96, with a median follow-up of 10.5 years, 83 patients developed an ipsilateral breast tumor recurrence, and 109 patients developed distant metastases resulting in an overall 10-year breast recurrence-free rate of 84%, and a 10-year distant metastasis-free rate of 78%. There were significant differences in clinical stage, pathological nodal involvement, and administration of systemic therapy between various histologic subtypes. As expected, those patients with histologies of low metastatic potential (such as intraductal, tubular, and mucinous) had significantly superior distant recurrence-free survival rates. With respect to breast relapse rates, there were no statistically significant differences in the 5- and 10-year breast recurrence-free rates between any of the histologic subtypes. Patients with intraductal carcinoma with or without focal invasion had similar breast relapse rates as those with other histologic subtypes. Patients with lobular carcinoma in situ as a histologic component also had a similar overall breast relapse-free recurrence rate. In conclusion, long-term follow-up of conservatively treated breast cancer patients demonstrates no significant differences in ipsilateral breast tumor recurrence rates between various histologic subtypes. There are no histologies which had a statistically significantly higher breast-relapse rate than infiltrating ductal carcinomas and therefore no primary histologic subtype represents a relative contraindication to breast conservation therapy. 相似文献
83.
84.
Corneal abrasion is the most common ocular injury occurring in the perioperative period. Corneal abrasion may occur during general anesthesia, monitored anesthesia care, regional anesthesia, or in the immediate recovery period. This injury is not usually apparent until the patient is in the PACU, and the perianesthesia nurse may be the first clinician to detect this complication. Preventive measures and vigilant care can help reduce the incidence of corneal abrasion in susceptible patients. Early detection and prompt intervention may help reduce the incidence of ocular morbidity. The purpose of this article is to explore the incidence, mechanism of injury, prevention, recognition, and treatment of perioperative corneal abrasion. 相似文献
85.
C K Dingee I G Cleator J K MacFarlane R M Christensen C L Birmingham J Appleby R H Gourlay 《Canadian journal of surgery》1990,33(1):25-27
Patients who have had ileogastrostomy for the treatment of morbid obesity require close, long-term follow-up. From a prospective study of a large number of variables in 12 consecutive patients, and from experience with more than 200 patients who have undergone this procedure since 1982, a protocol has evolved. The authors outline the associated morbid conditions, operative complications and biochemical alterations that are important in the management of these patients. 相似文献
86.
Attitudes of College Football Officials Regarding NCAA Mouthguard Regulations and Player Compliance 总被引:1,自引:0,他引:1
Dennis N. Ranalli DDS MDS Diana M. Lancaster PhD 《Journal of public health dentistry》1993,53(2):96-100
The National Collegiate Athletic Association (NCAA) mandates the use of brightly colored, intraoral mouth- guards by football players to reduce the frequency and severity of craniofacial and intraoral morbidity and mortality, and to enhance the ability of officials to observe player compliance. The purpose of this 12-question mail survey was to determine the attitudes of on-Held game officials regarding current NCAA mouthguard regulations and patterns of utilization by college football players. The sample consisted of all 50 Big East Football Conference officials; a response rate of 100 percent was achieved. Only 42 percent of the officials reported observing all players in compliance, and quarterbacks were identified by others as the least compliant group (52%). The majority (88%) indicated that the 1990 rule for brightly colored mouthguards had been beneficial to them in determining player compliance, and 52 percent reported that this rule had resulted in more frequent use by these athletes. Nearly all officials (96%) indicated that they would issue a warning for noncompliance to the player or coach, rather than charging a timeout for a violation as prescribed by NCAA regulations. The majority (70%) believe current enforcement is appropriate, but expressed the opinion that coaches should be held more accountable for player compliance. 相似文献
87.
D J Stennett W H Gerwick P K Egging J M Christensen 《JPEN. Journal of parenteral and enteral nutrition》1988,12(1):88-92
The composition of a precipitate obtained from a silastic right atrial catheter was determined. The precipitate was collected and washed with deionized water thoroughly before subjecting portions of it to organic and inorganic analysis. Inorganic analysis was conducted using scanning electron microscopy and x-ray spectroscopy for sodium, aluminum, silicone, sulfur, chlorine, and calcium. Phosphorus analysis was conducted by a commercial laboratory. Organic analysis was conducted by thin layer chromatography with cholesterol, phosphatidyl serine, phosphatidyl choline, phosphatidyl ethanolamine, and sphingomyelin as standards. Silicone, calcium, and phosphorus and three organic compounds, which could not be conclusively identified, were found. The precipitate was most likely calcium phosphate intermixed with silicone oil lubricant and residual total parenteral nutrition (TPN) solution. This formed in the catheter at body temperature probably due to incomplete catheter flushing. 相似文献
88.
The pattern of fluctuation in the population size of Bulinus globosus and Biomphalaria pfeifferi, in their infection rates with Schistosoma haematobium/S. mattheei and S. mansoni, respectively, and in the cercarial population size as monitored using hamster immersions, was elucidated in streams in the temperate highveld region of Zimbabwe over a 27-month period during 1982-1984. The results revealed that transmission of S. mansoni was erratic and unpredictable without a clearcut seasonal transmission pattern. In contrast, transmission of S. haematobium and S. mattheei exhibited a marked seasonal pattern, being most intensive during the hot, dry season (September-November) and markedly reduced during the cold, dry season (June-August). During the rainy (December-February) and warm, post-rainy (March-May) seasons transmission was moderate and variable, but occasionally intensive. The results also showed that rodent immersion is to be preferred to measurements of snail population size and snail infection rate in elucidating seasonality of transmission of schistosomiasis. 相似文献
89.
Unscheduled DNA synthesis (UDS) was studied by quantitative autoradiography in human urothelial cells of three transformation grades (TGr I-III). Cells incubated in arginine-free medium supplemented with hydroxyurea showed dose-dependent UDS after administration of agents injurious to DNA, while the scheduled synthesis of DNA was nearly totally suppressed. UDS was demonstrated after treatment with the ultimate carcinogen N-methyl-N-nitroso-N'-nitroguanidine (CAS: 70-25-7) or with the procarcinogen 4-nitroquinoline-1-oxide (4-NQO; CAS: 56-57-5). In cultures treated with benzo[a]pyrene (CAS: 50-32-8), which requires a different activation system than that for 4-NQO, UDS was less pronounced. In 9 cell lines the average rates of UDS were inversely related to TGr. Two cell lines showed a different pattern. 相似文献
90.
Intrinsic nerves in the mammalian colon: confirmation of a plexus at the circular muscle-submucosal interface 总被引:1,自引:0,他引:1
Slow waves in the small intestine seem to arise in plexuses of neurites with interstitial cells of Cajal. In the colon, slow waves appear to arise at the circular muscle - submucosal interface. We therefore sought a plexus at this surface in the colon in the cat, dog, ferret, opossum, rabbit, rat, guinea-pig and man. Segments from all levels of the colon were stained by the Champy-Maillet osmic acid-zinc iodide method and cut into serial 25 micron sections in the plane of the muscle layers. A dense network of neurites with abundant interstitial cells of Cajal was found at the circular muscle - submucosal interface in all species except rabbit. Neurites in this plexus appeared to arise from the deep plexus of the submucosa (Schabadasch's or Henle's plexus). It was not found in the small intestine and stomach. A similar plexus was found in the interstices of the myenteric plexus in the colon. Interstitial cells of Cajal in both plexuses were positive for the NADH-diaphorase stain, but not for silver impregnation. The possible roles of the plexuses of neurites and interstitial cells of Cajal at the circular muscle - submucosal interface and at the plane of the myenteric plexus in the generation of rhythmic activity in the colon are discussed. 相似文献