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61.
Tate  CF  d; Wilkov  HR; Lestrange  NR; Gardiner  HF; Stein  KR 《Radiology》1985,157(2):391-393
Seventy-nine patients underwent lumbar myelography on an outpatient basis, with a low (3.75 g) dose of metrizamide as the radiocontrast agent and a 25-gauge spinal needle used for lumbar puncture. No patient experienced significant neurotoxicity following the examination; 70.8% (56 of 79) experienced minimal (23%) or no (48%) side effects. Three patients (3.8%) were admitted to the hospital for management of common side effects (headache, nausea/vomiting, back pain). We obtained postmyelographic computed tomographic scans on 96% (76 of 79) of the patients. Our initial results suggest that outpatient lumbar myelography is safe and can be performed with a very acceptable incidence of side effects.  相似文献   
62.
In developing countries, maternal infections during lactation are common. In this study, we evaluated the effect of acute maternal postpartum infection on the composition of colostrum and early milk with special emphasis on milk proteins and trace elements. The study was carried out in two maternity hospitals in Lima, Peru. Subjects were normally nourished women (body mass index (BMI) > 20.0) who intended to exclusively breastfeed their child and who had fever and clinical symptoms of infection within the first 48 h postpartum ( n = 34). Non-ill women of similar characteristics were selected as controls ( n = 23). Blood and milk samples were taken on days 1 and 14 postpartum. An acute phase response was confirmed by significantly increased serum levels of C-reactive protein in infected women. Serum zinc levels increased significantly from day 1 to day 14, but were not affected by infection. Serum copper levels were significantly higher in ill women than in non-ill women on day 1. All participating women were breastfeeding on day 14. Whey protein levels, the whey/casein ratio and total protein levels decreased significantly with time, but were not affected by infection. There were no differences in milk iron or copper levels with time or infection. Milk zinc levels decreased significantly with time, but were not affected by infection. Maternal infection during the early postpartum period does not appear to adversely affect the initiation of lactation or milk protein and trace element contents.  相似文献   
63.
Som  PM; Lanzieri  CF; Sacher  M; Lawson  W; Biller  HF 《Radiology》1985,154(2):407-412
Twenty-eight patients had combined conventional drip infusion CT scans. The information about the anatomic location of the lesion, its configuration, its cross-sectional appearance, its vascularity (as determined by dynamic signature curves), and its clinical presentation were considered as a single overall unit. This diagnostic approach allowed a diagnosis to be made on virtually all of these enhancing lesions without resorting to either a digital venous imaging study or angiographic procedure. In 17 of these cases, such an invasive second procedure was performed either to confirm the CT impression as part of this study or as part of a therapeutic embolization procedure.  相似文献   
64.
Seventy-five patients with hemoptysis were treated with bronchial artery embolization (BAE). The procedure was performed with Hexabrix (sodium methylglucamine ioxaglate), Mikaelson catheters, and Gelfoam particles. Angiographic evaluation of the bronchial artery anatomy revealed ten different configurations, which are described. The embolization attempt failed in three cases (4%); eight additional patients (10.7%) were excluded from the series because of inadequate data. In the remaining 64 patients, 41 underwent BAE alone and 23 underwent either chemotherapy or surgery in addition to embolization. Immediate control of hemoptysis was achieved in 49 of 64 patients (76.6%). Long-term control of hemoptysis was achieved in 46 of the 56 patients included in the long-term follow-up (82.1%). Eight of the 64 patients were lost to follow-up, which ranged from one to 47 months (mean 24.8 months). Hemoptysis recurred in 12 of 56 patients (severe in 10, mild in 2) (21.4%). Twelve patients died (21.4%), five of them due to hemoptysis (8.9%). None of the patients who died of hemoptysis had responded to initial BAE. It is concluded that BAE is an effective treatment for immediate control of life-threatening hemoptysis, allowing long-term control of bleeding in the majority of patients.  相似文献   
65.

Background and purpose:

Thrombus formation is commonly associated with pulmonary arterial hypertension (PAH). Thrombin may thus play an important role in the pathogenesis and pathophysiology of PAH. Hence, we investigated the contractile effects of thrombin and its mechanism in pulmonary artery.

Experimental approach:

The cytosolic Ca2+ concentrations ([Ca2+]i), 20 kDa myosin light chain (MLC20) phosphorylation and tension development were evaluated using the isolated porcine pulmonary artery.

Key results:

Thrombin induced a sustained contraction in endothelium-denuded strips obtained from different sites of a pulmonary artery, ranging from the main pulmonary artery to the intrapulmonary artery. In the presence of endothelium, thrombin induced a transient relaxation. The contractile effect of thrombin was abolished by either a protease inhibitor or a proteinase-activated receptor 1 (PAR1) antagonist, while it was mimicked by PAR1-activating peptide (PAR1AP), but not PAR4AP. The thrombin-induced contraction was associated with a small elevation of [Ca2+]i and an increase in MLC20 phosphorylation. Thrombin and PAR1AP induced a greater increase in tension for a given [Ca2+]i elevation than that obtained with high K+-depolarization. They also induced a contraction at a fixed Ca2+ concentration in α-toxin-permeabilized preparations.

Conclusions and implications:

The present study revealed a unique property of the pulmonary artery. In contrast to normal arteries of the systemic circulation, thrombin induces a sustained contraction in the normal pulmonary artery, by activating PAR1 and thereby increasing the sensitivity of the myofilament to Ca2+. This responsiveness of the pulmonary artery to thrombin may therefore contribute to the pathogenesis and pathophysiology of PAH.  相似文献   
66.
67.
Cystic fibrosis pulmonary disease is characterized by excessive and prolonged inflammation. CF Pulmonary disease severity exhibits considerable variation that, to some extent, appears to be due to the presence of modifier genes. Several components of the inflammatory response are known to have altered regulation in the CF lung. Genetic variants in 52 inflammatory genes were tested for associations with lung disease indices in a CF patient population (n=737) homozygous for the DeltaF508 cystic fibrosis transmembrane conductance regulator mutation. Variants in three inflammatory genes showed significant genotypic associations with CF lung disease severity, including IL8 and previously reported TGFbeta1 (P< or =0.05). When analyzed by gender, it was apparent that IL8 variant associations were predominantly due to males. The IL8 variants were tested in an additional CF population (n=385) and the association in males verified (P< or =0.01). The IL8 variants were in strong linkage disequilibrium with each other (R2> or =0.82), while variants in neighboring genes CXCL6, RASSF6 and PF4V1 did not associate (P> or =0.26) and were in weaker LD with each other and with the IL8 variants (0.01< or =R2< or =0.49). Studies revealed differential expression between the IL8 promoter variant alleles (P<0.001). These results suggest that IL8 variants modify CF lung disease severity and have functional consequences.  相似文献   
68.
69.
Most pedobarographic studies of microsurgical foot reconstruction have been retrospective. In the present study, we report the results from a prospective pedobarographic study of a patient after microsurgical reconstruction of her foot with a latissimus dorsi flap and a cutaneous paddle, with a 42-month follow-up period. We describe the foot reconstruction plan and the pedobarographic measurements and analyzed its functional outcome. The goal of the present study was to demonstrate that pedobarography could have a role in the treatment of foot reconstruction from a quantitative perspective. The pedobarographic measurements were recorded after the initial coverage surgery and 2 subsequent foot remodeling procedures. A total of 4 pedobarographic measurements and 2 gait analyses were recorded and compared for both the noninvolved foot and the injured foot. Furthermore, the progress of the reconstructed foot was critically evaluated using this method. Both static and dynamic patterns were compared at subsequent follow-up visits after the foot reconstruction. The values and progression of the foot shape, peak foot pressure (kPa), average foot pressure (kPa), total contact surface (cm2), loading time (%), and step time (ms) were recorded. Initially, the pressure distribution of the reconstructed foot showed higher peak values at nonanatomic locations, revealing a greater ulceration risk. Over time, we found an improvement in the shape and values of these factors in the involved foot. To homogenize the pressure distribution and correct the imbalance between the 2 feet, patient-specific insoles were designed and fabricated. In our patient, pedobarography provided an objective, repeatable, and recordable method for the evaluation of the reconstructed foot. Pedobarography can therefore provide valuable insights into the prevention of pressure ulcers and optimization of rehabilitation.  相似文献   
70.
Beckmann  CF; Roth  RA 《Radiology》1987,164(2):365-367
Percutaneous incision and balloon catheter dilation of the ureteropelvic junction (UPJ) was performed in nine patients with secondary UPJ strictures. In all patients, the UPJ was successfully dilated, and no immediate complications were encountered. After a postoperative follow-up period of 4-27 months, six patients showed marked improvement on excretory urograms. Three patients had recurrent obstruction after 3-18 months. The 66% success rate of percutaneous balloon dilation with or without endopyelotomy compares favorably with the success rate of open surgical repair of secondary UPJ strictures in adults.  相似文献   
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