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991.
R Shayya RJ Chang 《BJOG : an international journal of obstetrics and gynaecology》2010,117(2):150-155
Polycystic ovary syndrome (PCOS) is the most common endocrinopathy among reproductive-aged women, and it typically presents during adolescence. The objective of this review is to describe the clinical manifestations of PCOS in adolescent girls and the underlying basis for the altered reproductive physiology. Recognising adolescents at risk for PCOS and taking the appropriate steps to reduce circulating androgen levels is critical in reducing the clinical symptomatology of this disorder, and the development of adulthood infertility, diabetes, and metabolic syndrome in patients with PCOS. 相似文献
992.
993.
Cholangiocarcinoma complicating primary sclerosing cholangitis: cholangiographic appearances 总被引:1,自引:0,他引:1
MacCarty RL; LaRusso NF; May GR; Bender CE; Wiesner RH; King JE; Coffey RJ 《Radiology》1985,156(1):43-46
Cholangiograms from 104 patients (and serial cholangiograms in 66 patients) with primary sclerosing cholangitis (PSC) were reviewed. In 13 patients the additional diagnosis of cholangiocarcinoma was made at biopsy or autopsy. Cholangiograms from patients with both PSC and carcinoma were compared with cholangiograms from patients with PSC alone. Marked dilatation of ducts or ductal segments (100% vs. 24%) and the appearance of a polypoid mass (46% vs. 7%) were common findings in the group of patients whose disease was complicated by malignancy. In the malignant group, polypoid masses were larger, measuring 1 cm or greater in diameter. On serial cholangiograms, four of 15 patients with progressive stricture formation and four of five with progressive ductal dilatation proved to have carcinomas. The frequent occurrence of bile duct carcinoma as a complication of PSC in this group of patients indicates that PSC has a strong tendency to undergo malignant degeneration. Cholangiographic findings which suggest malignant degeneration include markedly dilated ducts or ductal segments, presence of a polypoid mass 1 cm or greater in diameter, and progressive stricture formation or ductal dilatation. 相似文献
994.
Multi-section multi-echo pulse magnetic resonance techniques: optimization in a clinical setting 总被引:1,自引:0,他引:1
The user-selectable magnetic resonance imaging parameters involved in a multi-section multi-echo pulse sequence are described and their interrelationships explained. These parameters include repetition time (TR), echo delay time (TE), the number of sections (S), the number of echoes (E'), the time from the center of the last echo to the end of data acquisition (15 msec on the authors' system), and the time for T1 recovery. A simple mathematical relationship among these quantities, permitting easy calculation of the remaining parameters once a sufficient number have been specified, is given. In addition, a nomogram that permits rapid visual estimation of these parameters is presented. The effects of these choices and others is explained with respect to imaging time, region covered, and image contrast. Finally, the inherent trade-offs are illustrated in a clinical example involving the pelvis. 相似文献
995.
Loflin TG; Simeone JF; Mueller PR; Saini S; Stark DD; Butch RJ; Brady TJ; Ferrucci JT Jr 《Radiology》1985,157(2):457-459
Fifty-three samples of gallbladder bile were obtained at the time of cholecystectomy from patients with the clinical diagnosis of acute or chronic cholecystitis. Five bile samples from patients with clinically normal gallbladders also were obtained. Proton magnetic resonance (MR) relaxation times, protein content, and water content were determined for the bile samples, and the data were grouped according to pathologic diagnosis, which disclosed 11 cases of acute cholecystitis, 41 cases of chronic cholecystitis, and six normal gallbladders. There was no significant difference in the mean T1 and T2 values between the groups with acute and chronic cholecystitis. Patients with chronic cholecystitis were found to have more concentrated bile than those with acute cholecystitis. Protein content varied widely within both groups of patients. We conclude that T1 and T2 relaxation times do not reliably differentiate acute from chronic cholecystitis. 相似文献
996.
MR imaging in patients with metallic implants 总被引:11,自引:0,他引:11
Laakman RW; Kaufman B; Han JS; Nelson AD; Clampitt M; O'Block AM; Haaga JR; Alfidi RJ 《Radiology》1985,157(3):711-714
A total of 305 magnetic resonance (MR) examinations were performed in 236 patients with metallic implants. Most examinations were performed at 0.3 T. The metallic implants included central nervous system shunting devices, tantalum mesh, surgical wire, skin staples, surgical clips, metallic orthopedic devices, and a few miscellaneous metallic objects. Patients with cardiac pacemakers, electrical implants, prosthetic cardiac valves, and aneurysm clips were excluded from MR examinations. The images were reviewed for evidence of metallic artifact. The conspicuity of artifact was related to the composition, mass, orientation, and position of the metallic object in the body. In most instances, the metallic artifact did not interfere with the interpretation of the image. The patients' records were also reviewed for adverse effects noted by each patient during the MR examination. Only two patients reported discomfort that could possibly have been related to their metallic implants, but in both cases it seemed unlikely that the symptoms were actually related to the imaging process. There were no apparent short-term adverse effects demonstrated in these patients. 相似文献
997.
998.
999.
Mueller PR; Ferrucci JT Jr; Simeone JF; Butch RJ; Wittenberg J; White M; Brown AS 《Radiology》1985,155(3):615-618
Twelve abscesses and fluid collections in the lesser peritoneal sac were drained percutaneously using an access route across the intervening liver. This rather unusual access was chosen when other approaches were contraindicated because of surrounding colon, stomach, or spleen. All collections were drained successfully, and no specific complications such as hemorrhage, bile leak, or liver abscess occurred. Placement of an abscess drainage catheter should be done through the peripheral portion of the liver if possible. The technique offers a new, safe approach to percutaneous drainage of hitherto inaccessible collections. 相似文献
1000.
RJ Ruben IF Wallace J Gravel 《Indian journal of otolaryngology and head and neck surgery》1997,49(2):94-96
A cohort of lower socio-economic children who experienced multiple and prolonged episodes of otitis media (OM) during their first year of life were compared to an equivalent group of children who were largely free of OM during their first year. Both groups were followed until 9 years of age. The data indicate that children with positive histories of OM performed poorer on a variety of Iinguisitc tasks across the nine year age span than the children with the positive histories of OM. The results suggest that the effect of the otitis media and its accompanying hearing loss on communication skills may extend throughout childhood. 相似文献