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51.
This report describes the clinicopathologic and immunohistochemical features of 14 cases of epithelioid trophoblastic tumor (ETT), a distinctive but rare gestational trophoblastic tumor. The patients with this neoplasm were in the reproductive age group and presented with abnormal vaginal bleeding. Although diagnosis was usually associated with a gestational event, the latter was sometimes remote. Two of the 14 patients presented with extrauterine ETT without evidence of prior gestational trophoblastic disease in the uterus. Serum human chorionic gonadotropin levels were elevated in eight of nine patients in whom this information was available. In the uterus, ETT presented as a discrete, hemorrhagic, solid and cystic lesion that was located either in the fundus, lower uterine segment, or endocervix. Microscopically, the tumor was composed of a relatively uniform population of mononucleate intermediate trophoblastic cells forming nests and solid masses. The cells resemble the trophoblastic cells in the chorion laeve, and we have therefore designated them "chorionic-type intermediate trophoblast." Typically, islands of trophoblastic cells were surrounded by extensive necrosis and were associated with a hyaline-like matrix creating a "geographic" pattern that is quite characteristic of this lesion. The mean mitotic count was two mitoses per 10 high-power fields, and the average Ki-67 nuclear labeling index was 18%. Immunohistochemically, all cases were diffusely positive for inhibin-alpha, cytokeratin (AE1/AE3), epithelial membrane antigen, E-cadherin, prolyl 4-hydroxylase, and epidermal growth factor receptor but were only focally immunoreactive for human placental lactogen, human chorionic gonadotropin, PlAP, and Mel-CAM. The monomorphic growth pattern of ETT resembles placental site trophoblastic tumor to a much greater degree than choriocarcinoma which is characterized by a dimorphic population of trophoblast. In contrast to placental site trophoblastic tumor, the cells of ETT are smaller and display less nuclear pleomorphism. In addition, ETT grows in a nodular fashion compared with the infiltrative pattern of placental site trophoblastic tumor. In some of the cases, the trophoblastic cells in ETT replaced the endocervical surface epithelium, giving the appearance that the tumor was derived from the cervix. Moreover, because the associated hyaline-like material in ETT resembles keratin, the tumor can be misinterpreted as a keratinizing squamous cell carcinoma of the cervix. Ten patients underwent total hysterectomy and two had an endometrial curettage only. The two patients who presented with extrauterine ETT underwent small bowel resection and lung resection. Two of 12 patients with ETT in the uterus developed metastasis in the lungs and bone. One of these patients is alive with disease at 43 months and one patient was lost to follow-up after 2 months. One of the two patients who had extrauterine disease died of widespread tumor 36 months after diagnosis. The remainder of the patients are alive and well from 1 to 120 months. In summary, ETT is a rare trophoblastic tumor that simulates carcinoma and can behave in a malignant fashion. It appears to be less aggressive than choriocarcinoma, more closely resembling the behavior of placental site trophoblastic tumor. Based on the morphologic and immunohistochemical features, it appears that ETT develops from neoplastic transformation of chorionic-type intermediate trophoblast. 相似文献
52.
T Ikeda Y Murata EJ Quilligan JT Parer IM Theunissen P Cifuentes S Doi SD Park 《Canadian Metallurgical Quarterly》1998,179(5):1329-1337
OBJECTIVE: We previously showed that in asphyxiated fetal lambs the duration of hypotension correlated well with the severity of histologic damage to the brain, whereas the duration of bradycardia did not. This study compares fetal heart rate patterns with the degree of histologic damage to the brain. STUDY DESIGN: Twelve chronically instrumented near-term fetal lambs were subjected to asphyxia by umbilical cord occlusion until fetal arterial pH was <6. 9 and base excess was <-20 mEq/L. An additional 4 fetuses served as sham-asphyxia controls. Fetal heart rate (from electrocardiogram), arterial blood pressure, fetal breathing movements, and electrocorticogram were continuously monitored before, during, and for 72 hours after asphyxia. Fetal brain histologic features were categorized as mild (group 1, n = 5), moderate (group 2, n = 4), and severe (group 3, n = 3). Long-term fetal heart rate variability expressed as amplitude range was assessed visually every 5 minutes from 30 minutes before asphyxia until 2 hours of recovery and at 6, 12, 24, 48, and 72 hours of recovery. RESULTS: Long-term fetal heart rate variability amplitude decreased from 32 +/- 17 beats/min (mean +/- SEM) preocclusion to 4 +/- 13 beats/min at the end of occlusion (P <.001) without significant differences among the 3 groups. During 10 to 45 minutes of recovery, the long-term variability of group 1 was significantly greater than that of groups 2 and 3. At 24 to 72 hours of recovery, the long-term variability of groups 1 and 2 was significantly higher than that of group 3, which was almost 0. The "checkmark" and sinusoidal fetal heart rate patterns were observed during the recovery period in groups 2 and 3. CONCLUSIONS: Decreased long-term fetal heart rate variability and the "checkmark" and sinusoidal fetal heart rate patterns were indicators of the severity of asphyxial histologic damage in the fetal brain. 相似文献
53.
54.
IM Civello G Anastasio M Ippoliti M Salvatori L De Giovanni 《Canadian Metallurgical Quarterly》1993,48(21-22):1253-1260
The authors, after some remarks on the pathophysiology of primary alkaline gastritis, analyze the main methods, available at present, for diagnosis; they particularly consider the importance of endoscopy and histology, gastroesophageal 24-hours pH-metry and 99mTc HIDA scintigraphy. Successively, they present the criteria for the identification of patients who will predictably benefit from surgical treatment, and examine advantages and limits of the two main corrective surgical techniques for the duodenogastric reflux in patients not previously operated on the gastrointestinal tract: duodenal extramucosal myotomy according to Mattioli, relatively easy to perform, and the "duodenal switch" according to De Meester, technically more complex, but pathophysiologically more acceptable, completely eliminating the duodenogastric reflux. 相似文献
55.
GM Roshchina EB Lishnevskaia IA Sizova VA Orlova IM Tereshin 《Canadian Metallurgical Quarterly》1980,25(11):850-854
The technique of accumulating preparation of the mucosa and "turned out sac" was used to show that levorin, a polyenic antibiotic in a concentration of 10(-6) M, lowered the transport rate and accumulation of glucose by the epithelial cells of the rat thin intestine under conditions of oxygenation. Suppression of the glucose transport in the first stages resulted in partial inhibition of the transmembrane transfer. It is suggested that levorin suppression of the glucose transport through the erythrocyte apical membrane in the thin intestine is associated with a decrease in the electrochemical gradient of Na+. 相似文献
56.
The term dyshidrosis describes a nonspecific tissue pattern reaction characterized by a noninflammatory, pruritic (and sometimes burning) intraepidermal vesicular dermatosis involving selected areas of the fingers, palms, and soles. It should be distinguished from various pustular and vesicular dermatoses of the palms and soles with or without associated lesions elsewhere. When dyshidrotic lesions appear in areas where friction or pressure from the handling or wearing of sport gear occurs, the discomforting symptoms are noticeably accentuated and can thus interfere with the participant's effectiveness in the performance of the sport. A composite approach of dermatologic therapeutic acumen and physician-sponsored emotional support is essential in effectively handling this problem so that dyshidrosis does not "handicap" the patient. 相似文献
57.
James E. Warner Manuel I. Diaz Wilkins Aquino Marc Bonnet 《Computational Mechanics》2014,54(3):645-659
This work focuses on the identification of heterogeneous linear elastic moduli in the context of frequency-domain, coupled acoustic-structure interaction (ASI), using either solid displacement or fluid pressure measurement data. The approach postulates the inverse problem as an optimization problem where the solution is obtained by minimizing a modified error in constitutive equation (MECE) functional. The latter measures the discrepancy in the constitutive equations that connect kinematically admissible strains and dynamically admissible stresses, while incorporating the measurement data as additional quadratic error terms. We demonstrate two strategies for selecting the MECE weighting coefficient to produce regularized solutions to the ill-posed identification problem: 1) the discrepancy principle of Morozov, and 2) an error-balance approach that selects the weight parameter as the minimizer of another functional involving the ECE and the data misfit. Numerical results demonstrate that the proposed methodology can successfully recover elastic parameters in 2D and 3D ASI systems from response measurements taken in either the solid or fluid subdomains. Furthermore, both regularization strategies are shown to produce accurate reconstructions when the measurement data is polluted with noise. The discrepancy principle is shown to produce nearly optimal solutions, while the error-balance approach, although not optimal, remains effective and does not need a priori information on the noise level. 相似文献
58.
André Campaniço Dr. Marta P. Carrasco Dr. Mathew Njoroge Ronnett Seldon Prof. Kelly Chibale Dr. João Perdigão Prof. Isabel Portugal Prof. Digby F. Warner Prof. Rui Moreira Prof. Francisca Lopes 《ChemMedChem》2019,14(16):1537-1546
Herein we report the screening of a small library of aurones and their isosteric counterparts, azaaurones and N-acetylazaaurones, against Mycobacterium tuberculosis. Aurones were found to be inactive at 20 μm , whereas azaaurones and N-acetylazaaurones emerged as the most potent compounds, with nine derivatives displaying MIC99 values ranging from 0.4 to 2.0 μm . In addition, several N-acetylazaaurones were found to be active against multidrug-resistant (MDR) and extensively drug-resistant (XDR) clinical M. tuberculosis isolates. The antimycobacterial mechanism of action of these compounds remains to be determined; however, a preliminary mechanistic study confirmed that they do not inhibit the mycobacterial cytochrome bc1 complex. Additionally, microsomal metabolic stability and metabolite identification studies revealed that N-acetylazaaurones are deacetylated to their azaaurone counterparts. Overall, these results demonstrate that azaaurones and their N-acetyl counterparts represent a new entry in the toolbox of chemotypes capable of inhibiting M. tuberculosis growth. 相似文献
59.
With the rapid deployment of smart meters, utilities and regulators across the globe are considering the deployment of time-varying rates for residential customers. Our analysis of the impact of several studies of time-varying rates from across the globe finds that much of the discrepancy in results across the studies goes away once demand response is expressed as a function of the peak to off-peak price ratio. 相似文献
60.
A gel filtration chromatographic method has been developed which is capable of fractionating amylose and amylopectin in starch. Three GFC columns (2 × 4000 A and 1 × 300A PL Separation Sciences, Polymer Laboratories Ltd,) are used in series using sodium chloride solution as eluent. Minimal sample preparation is involved which includes a preliminary wetting of powder starch with ethanol followed by dissolution with sodium hydroxide. Since the solvent system is aqueous, cooked starch samples are analysed by direct dissolution with sodium hydroxide. The method shows promise as a rapid technique in elucidating starch structure. 相似文献