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51.
Volumetric rendering techniques: applications for three-dimensional imaging of the hip 总被引:1,自引:0,他引:1
Fishman EK; Drebin B; Magid D; Scott WW Jr; Ney DR; Brooker AF Jr; Riley LH Jr; St. Ville JA; Zerhouni EA; Siegelman SS 《Radiology》1987,163(3):737-738
Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images. 相似文献
52.
Radiologically guided balloon catheters were used to dilate 94 gastrointestinal strictures in 92 patients over a 6-year period. Fifty strictures were esophageal and 44 nonesophageal (22 gastroenterostomies, 11 antral-pyloric strictures, four colorectal strictures, four enteroenterostomies, and three miscellaneous strictures). Factors influencing the success of stricture intubation included patient age, stricture location (esophageal vs. nonesophageal and proximal vs. distal esophageal), and association with a surgical anastomosis. Malignancy was associated with greater postdilation irregularity and a smaller increase in stricture diameter, as measured radiographically. Procedural failures occurred in 8% of cases (2% of esophageal and 30% of nonesophageal lesions). Two small, asymptomatic mucosal tears were seen after dilation (one esophageal and one colonic); no other procedural complications occurred. Following successful dilation, 16 patients (17%; six with esophageal and ten with non-esophageal strictures) had recurrence of symptoms during short-term (30-day) follow-up. 相似文献
53.
Data obtained on 426 consecutive patients referred to a breast center by 122 physicians, including family practitioners, general surgeons, and other specialists, showed that the obstetricians-gynecologists referred the greatest average number of patients per physician, with more than 50% of these referrals for screening mammography. Internists referred fewer patients by nearly a factor of ten, with only one-third of these patients referred for screening mammography. Internists may be the weakest link in the utilization of screening mammography. 相似文献
54.
55.
Familial amyloidotic patients' experience of the disease and of liver transplantation 总被引:1,自引:0,他引:1
Elisabeth Jonsèn RNT Elsy Athlin RNT DR.med.sci. & Ole Suhr MD PhD 《Journal of advanced nursing》1998,27(1):52-58
Liver transplantation is a new treatment for familial amyloidotic polyneuropathy (FAP). No qualitative study examining these patients' experiences of the disease and the treatment has been published. The purpose of this study was to explore and describe the experience of the disease and the liver transplantation from the FAP patient's perspective. In-depth interviews with 11 liver transplant FAP patients were performed. The process of the FAP disease and a liver transplantation was found to involve the following categories: going downhill, defence and denial, a chance of surviving, the decision — no choice, waiting powerless and uncertain, the first few steps after surgery, freed from the death sentence, still disabled, mastering up strength to recover, and the need for support and help. 相似文献
56.
目的:低白蛋白血症是肝移植患者的常见并发症,也是患者预后的重要影响因素。肝移植术后选择合理的白蛋白应用方案将有益于提高肝移植患者术后近远期疗效。方法:选择2000-10/2005-06于北京大学第三医院行肝移植并且随访时间大于6个月的患者80例,对治疗方案均知情同意。医院自2003年8月开始改变了肝移植术后白蛋白的输入方案:①方案改变之前患者即白蛋白输入方案未改变组(n=50),术后早期常规输入白蛋白剂量大于60g/d。②方案改变之后患者即白蛋白输入方案改变组(n=30),适当减少术后早期白蛋白输入的常规剂量至0 ̄20g/d。统计分析两组患者的一般情况、术后白蛋白使用情况、预后情况及住院费用。另外,对于两组中术后存在低白蛋白相关严重并发症的患者进行进一步的比较分析。结果:80例患者全部进入结果分析。①两组患者术前及术中一般情况差异无显著性意义(P>0.05)。②白蛋白输入方案改变组术后早期白蛋白的使用量及其费用/总住院费用比例显著低于白蛋白输入方案未改变组(P<0.01)。但两组患者术后第3天肝功能情况、白蛋白水平、早期并发症发生率、早期死亡率、半年生存率及呼吸机时间等情况差异均无显著性意义(P>0.05)。③两组中术后出现低白蛋白相关严重并发症患者术后第3天肝功能情况、白蛋白水平、早期死亡率、半年生存率及呼吸机应用时间等情况差异均无显著性意义(P>0.05)。结论:肝移植术后过多输入白蛋白不能改善患者预后;适当减少术后白蛋白的常规输入剂量,同时根据血白蛋白水平及并发症情况随时调整白蛋白的输入量能够减少白蛋白的用量,对患者预后因素亦无明显影响。 相似文献
57.
Autoantibodies against bactericidal/permeability-increasing protein in patients with cystic fibrosis 总被引:5,自引:0,他引:5
Zhao MH; Jayne DR; Ardiles LG; Culley F; Hodson ME; Lockwood CM 《QJM : monthly journal of the Association of Physicians》1996,89(4):259-265
Cystic fibrosis (CF), a genetic disorder, is characterized by chronic
pulmonary infection/inflammation which leads to respiratory failure. The
presence of anti-neutrophil cytoplasmic autoantibodies (ANCA) has
previously been observed in the sera of patients with CF. In view of the
known relationship of ANCA with primary vasculitis and of their putative
pathogenetic role in these disorders, we studied the presence, specificity
and isotype of ANCA and their clinical associations in 66 adult CF
patients. None of the 66 CF samples had autoantibodies to the major ANCA
antigens, proteinase 3 or myeloperoxidase. However, 60/66 (91%) CF samples
contained IgG and 55/66 (83%) IgA, autoantibodies to
bactericidal/permeability increasing protein (BPI), a recently
characterized ANCA specificity. All the IgA anti-BPI-positive samples were
also IgG anti-BPI-positive. The autoantibody specificity was confirmed by
inhibition assay and immunoblotting of CF sera against a neutrophil granule
preparation. Furthermore, in this cross-sectional study, anti-BPI levels
were inversely correlated with the observed reductions in FEV1 and FVC (IgA
anti-BPI and FEV1: r = 0.508, <it>p</it> < 0.0001), and
both IgG and IgA anti-BPI levels were higher in CF patients with secondary
vasculitis (<it>n</it> = 6) than in those without
(<it>p</it> < 0.05). ANCA with specificity for BPI were
present in the majority of CF sera in this study and autoimmune processes
may be associated with the development of pulmonary injury in CF.
相似文献
58.
Stanworth SJ; Bhavnani M; Chattopadhya C; Miller H; Swinson DR 《QJM : monthly journal of the Association of Physicians》1998,91(1):49-56
Felty's syndrome (FS) (rheumatoid arthritis with neutropenia and
splenomegaly) has a poor prognosis, largely because of the high risk of
severe infection. Granulocyte colony-stimulating factor (G-CSF) is an
emerging treatment for chronic neutropenia. We prospectively monitored its
use in eight patients with recurrent infections or who required joint
surgery. Significant side-effects were documented in five, including
nausea, malaise, generalized joint pains, and in one patient, a vasculitic
skin rash. In two patients treatment had to be stopped, and in these cases
G-CSF had been started at full vial dosage (300 micrograms/ml filgrastim or
263 micrograms/ml lenograstim) alternate days or daily. G-CSF treatment was
continued in three patients by restarting at reduced dose, and changing the
proprietary formulation. G- CSF raised the neutrophil count, reduced severe
infection, and allowed surgery to be performed. A combined clinical and
laboratory index suggested that long-term treatment (up to 3.5 years) did
not exacerbate the arthritis. Once on established treatment, it may be
possible to use smaller weekly doses of G-CSF to maintain the same clinical
benefit. One of the three patients whose FS was associated with a large
granular T-cell lymphocytosis showed a reduction in this subset of
lymphocytes during G-CSF treatment.
相似文献
59.
The effect of sterilization on transforming growth factor beta isolated from demineralized human bone 总被引:1,自引:0,他引:1
Growth factors have been identified as the primary cause of osteoinduction in bone healing. Transforming growth factor beta (TGF- beta) has been shown to promote bone formation and is present in bone in high quantities. The aims of the present study were to isolate TGF- beta from human bone, demonstrate its biologic activity, and analyze the effects of conventional sterilization techniques on activity. Bone, obtained from femoral heads of five patients (mean age, 70 years) was ground, demineralized, and freeze-dried, and samples from each patient were divided into three groups: no treatment, sterilization with 1.60 to 1.94 Mrad of 60Co irradiation, and sterilization with ethylene oxide (ETO). Carrier-free recombinant TGF-beta control was also treated and was totally inactivated by ETO but not by irradiation (p < 0.01). TGF- beta activity in demineralized bone was not significantly diminished (p > 0.1) by either sterilization procedure, and substantial amounts of active TGF-beta were recovered in all bone samples: 1.04 +/− 0.77 ng per mg of protein in irradiated samples, 0.67 +/− 0.26 ng per mg in ETO- treated samples, and 1.04 +/− 0.33 in untreated samples, respectively (mean +/− SD). Although a recent report demonstrated that the osteoinductive activity of bone morphogenetic protein in bone powder is diminished considerably by ETO and by 2.5 Mrad of irradiation sterilization of bone powder, these data demonstrate that TGF-beta activity, with its osteoinductive properties, was not destroyed in more coarsely ground, demineralized bone by ETO or by lower doses of irradiation. These findings support the use of human bone allografts in clinical instances involving impaired bone formation. 相似文献
60.
David Galloway Ethan Mezoff Wujuan Zhang Melissa Byrd Conrad Cole Inmaculada Aban Samuel Kocoshis Kenneth DR Setchell James E Heubi 《JPEN. Journal of parenteral and enteral nutrition》2019,43(2):263-270
Background: We determined qualitative and quantitative serum unconjugated bile acid (SUBA) levels among children with history of intestinal failure (IF) and suspected small bowel bacterial overgrowth (SBBO). Methods: This was a single‐center, case‐control pilot study conducted at Cincinnati Children's Hospital Medical Center. Children with history of IF and suspected SBBO were enrolled as subjects. Age‐matched children without IF or suspected SBBO served as controls. All participants underwent small bowel fluid sampling for microbial culture analysis. Additionally, serum fractionated and total bile acids were measured by liquid chromatography‐mass spectrometry at enrollment and following treatment for SBBO. Results: SUBA concentrations were elevated in IF subjects (median 1.16 μM, range 0.43–10.65 μM) compared with controls (median 0.10 μM, range 0.05–0.18 μM, P = 0.001). Among SUBA, chenodeoxycholic acid (CDCA) was significantly elevated in subjects (median 0.8 μM, range 0–7.08 μM) compared with controls (median 0 μM, range 0–0.03 μM, P = 0.012). When controls were excluded from analysis, IF subjects with positive aspirates for SBBO demonstrated higher concentration of CDCA (median 7.36 μM, range 1.1–8.28 μM) compared with IF subjects with negative aspirates (median 0.18 μM, range 0–1.06 μM, P = 0.017). Treatment for SBBO did not alter SUBA concentration. Conclusions: SUBA concentrations are elevated in children with history of IF and presumed SBBO compared with non‐IF controls. CDCA was more prevalent in IF subjects with positive aspirates for SBBO compared with IF subjects with negative aspirates. The determination of SUBA concentration may be a useful surrogate to small bowel fluid aspiration in the diagnosis of SBBO in children with history of IF. 相似文献