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41.
On curettage, done in a 39 year old patient because of metorrhagia, a peanut-sized nodule was scraped away from the endometrium. Histologically it consisted of a jumble of irregularly shaped portions of normal appearing embryonal cartilage, of tortuous thick-walled vessels, of twisted bundles of nerves of ducts of respiratory and intestinal epithelium, and of sheets of hornifying skin. The haphazard disarray of tissues supported the notion that the lesion was not a remnant of a malformed embryo. Step-sections through the lesion revealed no traces of placental villi or decidua in the surrounding endometrium. The following were considered as possible origins of the teratoma: 1. displaced germinal cells, 2. retention of pluripotent müllerian epithelium, 3. overaged or blighted ovum. The latter seems most compatible with the histological findings. 相似文献
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43.
Two experiments were conducted to investigate the effects of varying levels of pantothenic acid on the efficiency of energy utilization and changes in body composition of the growing chick. The results indicate that a pantothenic acid deficiency does not interfere with the chick's ability to obtain metabolizable energy from the diet. The data do show that the efficiency of energy utilization and body composition were markedly affected when chicks were fed diets deficient in pantothenic acid. In both experiments, protein, fat and energy stores were significantly reduced when pantothenic acid-deficient diets were fed. Increased estimates of heat increment per gram of diet were observed when levels of pantothenic acid below the N.R.C. (1971) recommended level of 10 mg. per kg of diet were fed. 相似文献
44.
V Rodriguez J Gottlieb MA Burgess R Livingston W Wheeler G Spitzer GP Bodey GR Blumenschein EJ Freireich 《Canadian Metallurgical Quarterly》1976,38(2):690-694
Phase I studies were conducted in 58 adult cancer patients with Baker's Antifol (BAF), a new active-site directed inhibitor of dihydrofolate reductase. Dose escalation ranged from 10 to 250 mg/m2/day X 5 days and courses of treatment were repeated every 2-3 weeks. Biologic effects were observed mostly at doses greater than 100 mg/m2/day X 5 days. The patients developed myelosuppression during 19% of the trials. Other types of toxicity were dermatitis in 12 to 30% and stomatitis in 7 to 38% of the trials. Toxicity was directly related to the impairment of the patient's liver function. Two partial responses (in a patient with adenocarcinoma of the lung and a patient with transitional cell carcinoma of the bladder) occurred. BAF is an active new chemotherapeutic agent which deserves further clinical trials in patients with various malignancies. 相似文献
45.
46.
HP Kourea MH Bilsky DH Leung JJ Lewis JM Woodruff 《Canadian Metallurgical Quarterly》1998,82(11):2191-2203
BACKGROUND: To determine the effects of anatomic site on the presentation and diagnosis of malignant peripheral nerve sheath tumors (MPNSTs) and on the treatment and outcomes of the patients, the authors initiated a study of these tumors at different sites. An earlier report described MPNSTs of the buttock and lower extremity, and the current series analyzes those presenting at intrathoracic (IT) and subdiaphragmatic (SD) paraspinal sites. METHODS: The authors reviewed data on patients with paraspinal MPNSTs who were seen at Memorial Hospital during the period 1960-1995 and for whom histologic slides were available. Various clinicopathologic parameters and their effects on patient outcomes were examined. RESULTS: Twenty-five patients with 26 tumors were evaluated. Seven tumors were IT and 19 were SD; 60% of the patients had neurofibromatosis type 1 (NF1). Most patients presented with pain, and a diagnostic delay (of 3 months to 2 years) was often noted. Mean tumor sizes for SD and IT tumors were 14.3 cm and 6.6 cm, respectively. Most MPNSTs were composed of spindle cells in fascicles. Twenty-seven percent exhibited divergent differentiation. Twenty-four tumors were high grade, and a low grade component was identified in 8 tumors. Surgical resection was attempted for 23 tumors (88%), but complete resection was achieved in only 6 cases (23%). Eighty percent of the patients died of their tumors, 2-year and 5-year survival rates were 35% and 16%, and median survival was 8.5 months. Significant prognostic factors were tumor size <5 cm, the presence of a low grade component, and complete tumor resection. CONCLUSIONS: Paraspinal MPNSTs have more aggressive behavior than peripherally located tumors, mainly because of the difficulty encountered in resecting them completely. Prognoses of patients with MPNST at this site appear to be affected by resection status, tumor size, and tumor grade. 相似文献
47.
A Saunders S Hoibr?ten JJ Kraushaar BJ Kriss RJ Peterson RA Ristinen JT Brack G Hofman EF Gibson CL Morris 《Canadian Metallurgical Quarterly》1996,53(4):1745-1752
We calculated the electrostatic force between a planar interface, such as a planar-supported lipid bilayer membrane, and the tip of a stylus on which another lipid bilayer or some other biomacromolecular system might be deposited. We considered styli with rounded tips as well as conical tips. To take into account the effect of dynamical hydrogen-bonded structures in the aqueous phase, we used a theory of nonlocal electrostatics. We used the Derjaguin approximation and identified the systems for which its use is valid. We pointed out where our approach differs from previous calculations and to what extent the latter are inadequate. We found that 1) the nonlocal interactions have significant effects over distances of 10-15 A from the polar zone and that, at the surface of this zone, the effect on the calculated force can be some orders of magnitude; 2) the lipid dipoles and charges are located a distance L from the hydrophobic layer in the aqueous medium and this can have consequences that may not be appreciated if it is ignored; 3) dipoles, located in the aqueous region, can give rise to forces even though the polar layer is unchanged, and if this is ignored the interpretation of force data can be erroneous if an attempt is made to rationalize an observed force with a knowledge of an uncharged surface; 4) the shape of the stylus tip can be very important, and a failure to take this into account can result in incorrect conclusions, a point made by other workers; and 5) when L is nonzero, the presence of charges and dipoles can yield a force that can be nonmonotonic as a function of ionic concentration. 相似文献
48.
K Hayashi G Thabit JJ Bogdanske LN Mascio MD Markel 《Canadian Metallurgical Quarterly》1996,12(4):474-481
This study was designed to evaluate the effect of laser energy at nonablative levels on the ultrastructure of joint capsular collagen. The femoropatellar joint capsules of six mature New Zealand white rabbits were harvested immediately after death. Specimens were divided into three treatment groups (5, 10, and 15 watts) and one control group. Laser energy was applied using a holmium: YAG laser. Transmission electron microscopy showed significant ultrastructural alterations in collagenous architecture for all laser treatment groups, with increased fibril cross-sectional diameter for each of the treated groups. The fibrils began to lose their distinct edges and their periodical cross-striations at subsequently higher energy densities. A morphometric analysis showed that each subsequently higher laser energy caused a significant increase in collagen fibril diameter. Ultrastructural alteration of collagen fibril architecture caused by the thermal effect of laser energy is probably the dominant mechanism of laser-induced tissue shrinkage. 相似文献
49.
Eighteen and 23 FAA components were detected in the cyst wall and cyst fluid of E granulosus, respectively, by using automatic amino acid analyzer. The concentrations of most of the determined FAA were higher in the cyst fluid than those in the cyst wall, especially the taurine was 5-fold higher. Mebendazole treatment resulted in an increase in the concentration of alanine, valine, lysine, and taurine in both cyst wall and cyst fluid, the most notable being the alanine in the cyst wall. The results are interpreted as a coupling of glycolysis and amino acid metabolism, suggesting an involvement of FAA metabolism in the mechanism of Meb action. 相似文献
50.
Denis Spitzer Christian Baras Michael Richard Schfer Fabrice Ciszek Benny Siegert 《Propellants, Explosives, Pyrotechnics》2011,36(1):65-74
This study introduces the conception of an apparatus to crystallize continuously nanosized explosive or more generally nanosized organic materials. These materials can be elaborated in pure state or in form of mixtures of energetic and inert materials. The installation can produce nano‐RDX or nano‐PETN from 1 to 10 g h−1 using a reactor containing one ultrasonic piezoelectric transducer. The present study describes the different parameters which influence the crystallization process. It presents first results of the parametric study of the influence of these parameters. The most important parameters which were already identified are the frequency of the ultrasonic piezoelectric transducer, the nature of the solvent, the liquid level in the reactor, the temperatures in the system, and the passing time of the aerosol droplets in the oven. 相似文献