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991.
992.
CT findings in Swyer-James syndrome 总被引:4,自引:0,他引:4
Swyer-James syndrome (SJS) is usually diagnosed with plain chest radiographs obtained during inspiration/expiration. The authors studied patients with CT to assess its value in the evaluation of this syndrome. In patients with SJS, CT was useful in the determination of bronchial patency (all nine patients), lung parenchymal changes (subpleural infiltrates in six patients, atelectasis in two, and cavities in two), and the extent and degree of bronchiectasis (all nine patients). If CT is used for the evaluation of bronchiectasis, knowledge of the main findings associated with SJS (hyperlucent lung without anteroposterior gradient attenuation [n = 8], small lung [n = 6], and diminished central and peripheral pulmonary arteries [n = 9]) should facilitate the diagnosis of associated SJS. Expiration CT would support the diagnosis with demonstration of air trapping. 相似文献
993.
Improved control of image optical density with low-dose digital and conventional radiography in bedside imaging 总被引:1,自引:0,他引:1
Schaefer CM; Greene RE; Oestmann JW; Kamalsky JM; Hall DA; Llewellyn HJ; Robertson CL; Rhea JT; Rosenthal H; Rubens JR 《Radiology》1989,173(3):713-716
The technical and diagnostic performance of simultaneously acquired low-dose (44% of standard dose) storage-phosphor digital radiographs (system resolution = 0.2 mm, 10 bits) were compared with those of standard-dose conventional bedside radiographs of the chest in 32 patients. The mean optical density (OD) of the lungs (800 measurements) was closer to the ideal density with digital radiography (1.45 OD +/- 0.20 [standard deviation] vs 1.75 OD +/- 0.53) and was less often outside the usable range (2.5% vs 42.5%). Receiver operating characteristic analysis for detection of simulated nodules and monitoring devices (nine readers, 4,608 observations) showed that digital radiography was superior to conventional radiography (P less than .05) for four of the nine readers and equivalent to conventional radiography for five readers. The authors concluded that digital radiography produces more consistent and ideal image density and performs at least as well as conventional radiography under phantom test conditions. 相似文献
994.
应用导数光谱法考察苯呋洛尔溶液体外经皮渗透性 总被引:1,自引:0,他引:1
本文应用二阶导数紫外分光光度法考察了苯呋洛尔溶液体外经皮渗透性。考察了促进剂月桂氮(?)酮-丙二醉及PEG-400溶剂对其渗透性的影响。应用二阶导数紫外分光光度法消除了兔皮溶出物对一般紫外测定方法的干扰。结果表明:苯呋洛尔溶液具有体外经皮渗透性;月桂氮(?)酮-丙二醇系统及PEG-400均能增强苯呋洛尔溶液的体外经皮渗透性。 相似文献
995.
996.
Magnetic resonance (MR) imaging was performed on 15 healthy subjects to define the appearance of the iliopsoas muscle and on 15 patients with iliopsoas disease. Seven patients had tumorous involvement of the muscles, five had inflammatory disease, one had retroperitoneal hemorrhage, one had iliopsoas bursitis, and one had bilateral hypertrophy. MR imaging permitted delineation of the muscles and depiction of the disease condition. Transverse MR images alone almost always provided the necessary data to determine the origin and extent of disease. Sagittal images were occasionally useful in defining the extension of disease into the spine. T1-weighted images provided optimal contrast between the muscles and adjacent tissues, while T2-weighted images were more useful for depicting disease within the muscles themselves. 相似文献
997.
Odone-Filho V Almeida MT Bakhit S Maluf PT Peron PP Aquino MZ Cristofani LM 《Journal of pediatric hematology/oncology》2005,27(4):227-228
Infectious diseases represent one of the most important secondary problems related to the treatment of childhood cancer, being the leading cause of death in this population. They are predominantly of bacterial and fungal etiology. The association between tetanus, a bacterial vaccine-preventable disease, and cancer is virtually undescribed. The authors present the case of a previously nonimmunized child, due to his parents' choice, who developed severe tetanus with an ulcerated rhabdomyosarcoma as portal of entry. Due to an unfavorable evolution, the child underwent a hip disarticulation to provide tetanus control. The ulterior tumor management was successful: the child has been off therapy for more than 108 months with no evidence of disease. 相似文献
998.
Kjeld?P?van Houwelingen Boukje?AC?van DijkEmail author Christina?A?Hulsbergen-van de Kaa Leo?J?Schouten Hanneke?JM?Gorissen Jack?A?Schalken Piet?A?van den Brandt Egbert?Oosterwijk 《BMC cancer》2005,5(1):57
Background
Biallelic von Hippel-Lindau (VHL) gene defects, a rate-limiting event in the carcinogenesis, occur in approximately 75% of sporadic clear-cell Renal Cell Carcinoma (RCC). We studied the VHL mutation status in a large population-based case group. 相似文献999.
Bone Mineral Density Increases in Trans Persons After 1 Year of Hormonal Treatment: A Multicenter Prospective Observational Study 下载免费PDF全文
Chantal M Wiepjes Mariska C Vlot Maartje Klaver Nienke M Nota Christel JM de Blok Renate T de Jongh Paul Lips Annemieke C Heijboer Alessandra D Fisher Thomas Schreiner Guy T'Sjoen Martin den Heijer 《Journal of bone and mineral research》2017,32(6):1252-1260
Sex steroids are important determinants of bone acquisition and bone homeostasis. Cross‐sex hormonal treatment (CHT) in transgender persons can affect bone mineral density (BMD). The aim of this study was to investigate in a prospective observational multicenter study the first‐year effects of CHT on BMD in transgender persons. A total of 231 transwomen and 199 transmen were included who completed the first year of CHT. Transwomen were treated with cyproterone acetate and oral or transdermal estradiol; transmen received transdermal or intramuscular testosterone. A dual‐energy X‐ray absorptiometry (DXA) was performed to measure lumbar spine (LS), total hip (TH), and femoral neck (FN) BMD before and after 1 year of CHT. In transwomen, an increase in LS (+3.67%, 95% confidence interval [CI] 3.20 to 4.13%, p < 0.001), TH (+0.97%, 95% CI 0.62 to 1.31%, p < 0.001), and FN (+1.86%, 95% CI 1.41 to 2.31%, p < 0.001) BMD was found. In transmen, TH BMD increased after 1 year of CHT (+1.04%, 95% CI 0.64 to 1.44%, p < 0.001). No changes were observed in FN BMD (–0.46%, 95% CI –1.07 to 0.16%, p = 0.144). The increase in LS BMD was larger in transmen aged ≥50 years (+4.32%, 95% CI 2.28 to 6.36%, p = 0.001) compared with transmen aged <50 years (+0.68%, 95% CI 0.19 to 1.17%, p = 0.007). In conclusion, BMD increased in transgender persons after 1 year of CHT. In transmen of postmenopausal age, the LS BMD increased more than in younger transmen, which may lead to the hypothesis that the increase in BMD in transmen is the result of the aromatization of testosterone to estradiol. © 2017 American Society for Bone and Mineral Research. 相似文献
1000.
Bourgeois P; Bolcato-Bellemin AL; Danse JM; Bloch-Zupan A; Yoshiba K; Stoetzel C; Perrin-Schmitt F 《Human molecular genetics》1998,7(6):945-957
Most targeted gene mutations are recessive and analyses of gene function
often focus on homozygous mutant phenotypes. Here we describe parts of the
expression pattern of M-twist in the head of developing wild-type mice and
present our analysis of the phenotype of heterozygous twist- null animals
at around birth and in adults. A number of twist -null heterozygous mice
present skull and limb defects and, in addition, we observed other
malformations, such as defects in middle ear formation and the xyphoid
process. Our study is of interest to understand bone formation and the role
of M-twist during this process, as within the same animal growth of some
bones can be accelerated while for others it can be delayed. Moreover, we
show here that expressivity of the mouse mutant heterozygous phenotype is
dependent on the genetic background. This information might also be helpful
for clinicians, since molecular defects affecting one allele of the human
H-twist ( TWIST ) gene were identified in patients affected with
Saethre-Chotzen syndrome (SCS). Expressivity of this syndrome is variable,
although most patients present craniofacial and limb malformations
resembling those seen in mutant mice. Thus the mutant mouse twist -null
strain might be a useful animal model for SCS. The twist -null mutant mouse
model, combined with other mutant mouse strains, might also help in an
understanding of the etiology of morphological abnormalities that appear in
human patients affected by other syndromes.
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