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排序方式: 共有301条查询结果,搜索用时 15 毫秒
1.
Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献
2.
Is the outcome of in-vitro fertilization and embryo transfer treatment improved by spontaneous or surgical drainage of a hydrosalpinx? 总被引:4,自引:7,他引:4
Sowter MC; Akande VA; Williams JA; Hull MG 《Human reproduction (Oxford, England)》1997,12(10):2147-2150
A pilot study was designed to examine whether the outcome of embryo
transfer in women with a hydrosalpinx might be improved by surgical
drainage of the hydrosalpinx at the time of oocyte collection for in- vitro
fertilization treatment. A comparative, controlled but retrospective
analysis of the results was performed of all women with infective tubal
damage aged <40 years old, who had ovulatory cycles, a normal uterus and
a partner with normal spermatozoa. A standardized treatment regimen was
used. A maximum of three embryos were transferred. Hydrosalpinx was defined
by prior hysterosalpingography and/or laparoscopy with transcervical dye
injection. A total of 237 embryo transfer cycles in women with
hydrosalpinges (tubal distension not visible in 151, visible but not
drained in 30 and drained in 56) were compared with 705 embryo transfer
cycles in women with tubal disease but no hydrosalpinx. Results were
analysed in the first three cycles but also separately in the first cycle
to check for bias. Success rates were higher in the first cycle, but did
not significantly influence overall differences. Implantation rates were
significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2%
for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup
without evident tubal distension and 7.5% (not significant) in the drained
hydrosalpinx group. This study shows that tubal damage with distal
occlusion is associated with a marked reduction in embryo implantation,
even in the absence of obvious fluid distension. Surgical drainage of
distended hydrosalpinges appears to offer no benefit.
相似文献
3.
目的对十年前后精神分裂症患者用药情况的变化进行调查分析.方法对十年前后两个五年段的各500份符合精神分裂症诊断标准的病历进行回顾性调查,并对各项指标进行对比分析.结果两组折算用药剂量经t检验差异无显著性(P>0.05);两组合并用药、合并抗胆碱药及疗效经χ2检验差异有显著性(P<0.01);十年后非典型抗精神病药物氯氮平在临床上的应用比例明显增大并上升为首位.结论十年前后两组抗精神病药的应用发生了明显变化,疗效好、副作用轻的非典型抗精神病药的应用比例明显增加. 相似文献
4.
Emergency portacaval shunt for control of hemorrhage from a parenchymal fracture after adult-to-adult living donor liver transplantation 总被引:2,自引:0,他引:2
Marcos A Fisher RA Ham JM Olzinski AT Shiffman ML Sanyal AJ Luketic VA Sterling RK Posner MP 《Transplantation》2000,69(10):2218-2221
As more adults undergo transplantation with partial liver grafts, the unique features of these segments and their clinical significance will become apparent. A patient presented with life-threatening hemorrhage from an iatrogenic laceration to a right lobe graft 11 days after transplantation. The creation of a portacaval shunt effectively controlled the bleeding, allowing more elective replacement of the organ with another right lobe graft. The regeneration process combined with increased portal blood flow and relative outflow limitation may have set the stage for this complication. Any disruption of the liver parenchyma during transplantation should be securely repaired and followed cautiously. Portacaval shunting is an option for controlling hemorrhage from the liver in transplant recipients. The timely availability of a second organ was likely the ultimate determinant of survival for this patient. 相似文献
5.
Saroj Neupane M.D. Naga VA Kommuri M.D. Noora Kazanji D.O. Pertha Chowdhury M.D. F.A.C.C. 《Echocardiography (Mount Kisco, N.Y.)》2016,33(11):1788-1789
Development of left ventricular pseudoaneurysm is a rare complication of mitral valve surgery and requires urgent surgical intervention. We describe a case of pseudoaneurysm of membranous septum following repeat mitral valve replacement with the use of multimodality imaging. 相似文献
6.
7.
Clinical and histologic spectrum of nonalcoholic fatty liver disease associated with normal ALT values 总被引:34,自引:0,他引:34
Mofrad P Contos MJ Haque M Sargeant C Fisher RA Luketic VA Sterling RK Shiffman ML Stravitz RT Sanyal AJ 《Hepatology (Baltimore, Md.)》2003,37(6):1286-1292
A retrospective study was performed to (1) characterize the clinical and histologic features of those with nonalcoholic fatty liver disease (NAFLD) and normal alanine aminotransferase (ALT) values, (2) compare the spectrum of NAFLD associated with normal versus elevated ALT levels, and (3) determine whether there were differences in the clinical or histologic spectrum of NAFLD between those with a low normal versus high normal ALT value. A total of 51 subjects with NAFLD and normal ALT were identified and compared with 50 consecutive subjects with NAFLD and elevated ALT. The major indications for liver biopsy in those with normal ALT were unexplained hepatomegaly (n = 21) and evaluation as a potential donor for living donor liver transplantation (n = 16). The 2 groups were comparable with respect to age, gender distribution, and ethnicity. Approximately 80% of cases in both groups had at least 1 feature of the metabolic syndrome, the major risk factor for NAFLD. The 2 groups were also comparable with respect to the grade of the individual histologic parameters of NAFLD. A total of 12 subjects with normal ALT levels had bridging fibrosis, whereas 6 had cirrhosis. Diabetes was the only factor independently associated with an increased risk of advanced fibrosis (bridging fibrosis or cirrhosis) by multivariate analysis (relative risk: 2.3, P <.01). The mean steatosis (1.6 vs. 2.16, P <.04) and perisinusoidal fibrosis scores (0.35 vs. 0.9, P <.049) were lower in those with low normal (<30 IU/L) ALT versus high normal ALT. However, the prevalence of advanced fibrosis was similar (5 of 15 vs. 13 of 36, respectively). In conclusion, (1) the entire histologic spectrum of NAFLD can be seen in individuals with normal ALT values, (2) the histologic spectrum in these individuals is not significantly different from those with elevated ALT levels, and (3) a low normal ALT value does not guarantee freedom from underlying steatohepatitis with advanced fibrosis. 相似文献
8.
Sterling RK Sanyal AJ Luketic VA Stravitz RT King AL Post AB Mills AS Contos MJ Shiffman ML 《The American journal of gastroenterology》1999,94(12):3576-3582
OBJECTIVES: Hepatitis C virus (HCV) is common in patients with end stage renal disease (ESRD) awaiting renal transplantation (RT). However, few data are available on the liver histology and viral titer in these patients relative to patients with HCV and normal renal function. The aims of this study were to assess liver histology, quantitative HCV-RNA titer, and alanine aminotransferase (ALT) levels in patients with ESRD awaiting RT, and to identify clinical predictors of histological progression to advanced bridging fibrosis and/or cirrhosis. METHODS: A total of 50 consecutive patients (mean age 42 yr, 62% male) with ESRD and HCV, who were awaiting RT, underwent liver biopsy. Two HCV populations, one with persistently normal ALT and another with elevated ALT, both with normal renal function, served as controls. HCV-RNA titer was assessed by quantitative PCR. RESULTS: Of the patients with ESRD, 94% had normal ALT. Log HCV RNA titer was significantly higher in patients with ESRD (5.8+/-0.3) than in either normal ALT (5.4+/-0.1) or elevated ALT (5.3+/-0.1) controls (p < 0.05). Knodell Histological Activity Index (HAI) in patients with ESRD was similar to that observed in control patients with normal ALT (4.8+/-0.4 vs 4.9+/-0.4) but significantly less (p < 0.05) than that observed in control patients with elevated ALT (8.4+/-0.5). The percentage of patients with bridging fibrosis or cirrhosis was similar in patients with ESRD and controls with persistently normal ALT (22% vs 13%) but significantly less (p < 0.001) than that observed in control patients with elevated ALT (48%). No significant differences in ALT, HCV-RNA titer, duration on hemodialysis, or time from first possible exposure was observed between ESRD patients with advance fibrosis (n = 11) and those with mild disease (n = 39). CONCLUSIONS: Our data suggest that liver biopsy is necessary to exclude significant liver pathology in patients with HCV and ESRD, and to help define those patients in whom interferon treatment might be helpful. 相似文献
9.
R A Morey J E Dunsmoor C C Haswell V M Brown A Vora J Weiner D Stjepanovic H R Wagner III VA Mid-Atlantic MIRECC Workgroup K S LaBar 《Translational psychiatry》2015,5(12):e700
Fear conditioning is an established model for investigating posttraumatic stress disorder (PTSD). However, symptom triggers may vaguely resemble the initial traumatic event, differing on a variety of sensory and affective dimensions. We extended the fear-conditioning model to assess generalization of conditioned fear on fear processing neurocircuitry in PTSD. Military veterans (n=67) consisting of PTSD (n=32) and trauma-exposed comparison (n=35) groups underwent functional magnetic resonance imaging during fear conditioning to a low fear-expressing face while a neutral face was explicitly unreinforced. Stimuli that varied along a neutral-to-fearful continuum were presented before conditioning to assess baseline responses, and after conditioning to assess experience-dependent changes in neural activity. Compared with trauma-exposed controls, PTSD patients exhibited greater post-study memory distortion of the fear-conditioned stimulus toward the stimulus expressing the highest fear intensity. PTSD patients exhibited biased neural activation toward high-intensity stimuli in fusiform gyrus (P<0.02), insula (P<0.001), primary visual cortex (P<0.05), locus coeruleus (P<0.04), thalamus (P<0.01), and at the trend level in inferior frontal gyrus (P=0.07). All regions except fusiform were moderated by childhood trauma. Amygdala–calcarine (P=0.01) and amygdala–thalamus (P=0.06) functional connectivity selectively increased in PTSD patients for high-intensity stimuli after conditioning. In contrast, amygdala–ventromedial prefrontal cortex (P=0.04) connectivity selectively increased in trauma-exposed controls compared with PTSD patients for low-intensity stimuli after conditioning, representing safety learning. In summary, fear generalization in PTSD is biased toward stimuli with higher emotional intensity than the original conditioned-fear stimulus. Functional brain differences provide a putative neurobiological model for fear generalization whereby PTSD symptoms are triggered by threat cues that merely resemble the index trauma. 相似文献
10.