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81.
Pulmonary lymphangitic spread of carcinoma: appearance on CT scans   总被引:6,自引:0,他引:6  
Stein  MG; Mayo  J; Muller  N; Aberle  DR; Webb  WR; Gamsu  G 《Radiology》1987,162(2):371-375
Chest computed tomography (CT), including high-resolution CT with thin (1.5-mm) sections was used to evaluate proved (pathologically or clinically) lymphangitic spread (LS) of tumor in 12 patients. These appearances were compared with thin-section scans obtained in 11 healthy subjects. Thin-section CT demonstrated findings consistent with thickening of the normal lung interstitium. In all patients, thin sections showed an increase in the number of peripheral lines (1-2 cm in length) that were diffuse in generalized disease and localized in focal disease. Normal peripheral arcades were not increased in number, but the limbs forming the arcades were thickened in all patients. A diffuse increase in linear and curvilinear structures (reticular pattern) was seen toward the center of the lung. Polygonal structures 1-2 cm in diameter were seen in seven patients with LS but not in healthy subjects. Fissures were thickened in nine patients. Selected 1.5-mm-thick CT sections are recommended through abnormal areas (seen at CT or on chest radiographs) or if these are normal at three levels (midapex, hilus, and 3 cm above the diaphragm) when scanning patients with tumors known to cause LS.  相似文献   
82.
An experimental model is presented for studying axonal growth after experimental hyperthyroidism and hypothyroidism. The left sciatic nerve of the rat was transected and transposed to the back. The proximal nerve stump was inserted into a 50-mm-long mesothelial chamber leaving the distal end of the chamber open. Different groups of young adult rats were given daily injections of thyroxine (10 micrograms/100 g body weight) or the goitrogen, thiamazol, in the drinking water (0.125 g/liter) for 12 weeks. Thyroxine treatment increased significantly the extent of axonal outgrowth from the proximal nerve stump compared with untreated rats. Experimental hypothyroidism (thiamazol treatment), evidenced by a retarded body growth, did not affect the extent of axonal outgrowth. In other experiments the left proximal nerve stump was cross-anastomosed with the right distal nerve stump. The two nerve stumps were bridged with a mesothelial chamber leaving a 15-mm gap. This gap distance is known from our previous studies to inhibit axonal overgrowth to the distal nerve stump. As evidenced by histological evaluation, in three of six thyroxine-treated rats, axons had bridged the 15-mm gap. We conclude that experimentally induced hyperthyroidism enhances axonal growth in mesothelial chambers.  相似文献   
83.
Morphological studies have indicated that proximal nerve ends of transected rat sciatic nerves regenerating into preformed mesothelial chambers show a different organization as compared to neuromas developed in contact with a muscle fascia. We have studied the physiological properties of nerve fibres arising from these types of preparations with reference to ongoing activity, response to mechanical stimulation and noradrenaline sensitivity. The study included also fibres arising from ligated and encapsulated neuromas. Fibres with ongoing activity arising from the neuroma could be found from neuromas in contact with a muscle fascia and also from ligated and encapsulated neuromas. This ongoing activity was enhanced by mechanical stimulation and i.v. infusion of noradrenaline. In contrast, fibres arising from proximal nerve ends in mesothelial chambers did not show ongoing activity. These silent fibres responded dynamically to light mechanical stimulation. Noradrenaline did not induce ongoing activity in these fibres.  相似文献   
84.
Eight patients (seven post partum, one post abortion) with massive pelvic hemorrhage related to pregnancy and one patient with uncontrollable bleeding following a cervical biopsy underwent angiography to facilitate the identification and treatment of bleeding sites. In all nine patients pelvic hemorrhage was successfully controlled with embolization under angiographic guidance. Angiographic embolization allowed preservation of the uterus in six patients referred prior to hysterectomy, and one patient subsequently became pregnant. When conservative measures and minor surgical repairs have failed, embolization should be the next step in the treatment of postpartum hemorrhage to avoid major surgery in an unstable patient and to maintain reproductive function.  相似文献   
85.
Several studies have shown the benefit of withdrawal therapy when medication overuse headache (MOH) is suspected. Our aim was to compare the effect of withdrawal therapy in patients followed by a neurologist (group A, n  = 42) and a primary care physician (PCP) (group B, n  = 38). Patients were randomized to A or B, and follow-up was at 3, 6 and 12 months. Calculated mean headache (MH at 6 months + MH at 12 months)/2 (primary end-point) was similar; A 1.04 (0.87, 1.21) and B 1.02 (0.82, 1.21) ( P  = 0.87). The number of patients with 50% improvement of headache days was also similar; 14/42 in group A vs. 12/34 in B ( P  = 0.86) at 3 months, 15/42 vs. 11/33 ( P  = 0.83) at 6 months and 15/42 vs. 14/38 ( P  = 0.92) at 12 months. Days without headache during the last 9 months of follow-up were 123 (96, 150) in group A and 137 (112, 161) in B ( P  = 0.62). After 3 months one-third were classified as MOH. Patients with MOH improved similarly in group A and B, and so did patients without MOH. Within 1 year 7/42 in A and 9/38 in B had recurrent medication overuse ( P  = 0.43). In summary, there were no significant differences in follow-up results between the two groups.  相似文献   
86.
We studied regeneration distance of rat sciatic nerve, with the sensory pinch reflex test and immunocytochemical staining for neurofilaments, four to 21 days after transsection, repair, and enclosure of the repair site in either a non-absorbable silicone tube or an absorbable polyglycolic acid (PGA) tube. The size of both tube-types was carefully selected so that they did not compress the repaired nerve. The opposite nerve was repaired and not inserted in a tube (control). The regeneration distances in repaired nerves enclosed in silicone tube were significantly longer than the control side at all time points, a result not seen when PGA tube was used. The number of proliferating non-neuronal cells (incorporation of 5-bromodeoxyuridine (BrdU)) was studied just proximal to the site of nerve repair after six days. Numerous stained cells were seen, but there where no significant differences between the groups. We conclude that outgrowth of sensory axons after transsection and repair of rat sciatic nerve with sutures can be increased by enclosing the site of repair in a silicone tube but not in a PGA tube. The effect is probably not related to the number of proliferative non-neuronal cells.  相似文献   
87.
88.
To study the effects of drying on regeneration, crush lesions were made on the sciatic nerve of 38 rats and the injured area was then air-dried for various periods of time (0-60 min). The regeneration distance of sensory nerve fibres was measured by the pinch reflex test three or six days later. Regeneration was significantly impaired by drying the nerve for 30 or 60 min, but shorter periods (10 min) also seemed to affect axonal outgrowth. Regeneration distances were increased in nerves that were subjected to drying and then allowed to recover for a week (conditioning interval) before the nerve was crushed. The results show that drying of a peripheral nerve is detrimental to nerve regeneration, and we suggest that nerves should not be exposed to air for more than a few minutes during operation without irrigation.  相似文献   
89.
BACKGROUND: The transmission of viral infections via protein concentrates made from a large pool of plasma depends on the selection of donors, fractionation process, and virucidal methods. To date, no data are available on the infectivity risk of plasma concentrates of the inhibitor of the first component of complement (C1-INH). STUDY DESIGN AND METHODS: The prevalence of blood-borne viral infections and levels of transaminases were evaluated in patients treated with a large- pool plasma concentrate of the inhibitor of C1-INH before and after the introduction of virucidal methods. The study included 85 patients with hereditary angioedema and 4 with acquired angioedema. The patients were divided into three groups: 1) 48 untreated patients; 2) 22 patients treated with non-virus-inactivated C1-INH concentrates; and 3) 19 patients treated with virus-inactivated concentrates. Serum samples obtained at various times after the infusion of concentrate were assayed for alanine amino-transferase and tested for hepatitis B surface antigen and antibodies to hepatitis C virus (anti-HCV) and human immunodeficiency virus (anti-HIV); anti-HCV-negative subjects exposed to the concentrate were also tested for HCV RNA. RESULTS: Prevalences of HCV infection and elevated alanine aminotransferase are significantly lower in patients treated with virus-inactivated concentrates than in those exposed to non-virus-inactivated concentrates. No patients were anti-HIV positive. CONCLUSION: This study suggests that C1-INH concentrates transmitted HCV, but that the virucidal methods adopted are effective in reducing the infectivity.  相似文献   
90.
Transition to a new work area is often stressful for both experienced and new graduate nurses. It is essential that the new graduate be supported through this transition period to enable them to adjust to the environment itself, refine knowledge, and develop skills specific to their chosen clinical stream. In past years, several strategies have been designed with varying levels of success.This study evaluates an Australian transition support model, where the fundamental difference is that the management of the program is facilitated by a nurse possessing refined leadership, communication, clinical and organisational skills.The model has been evaluated on its effectiveness in meeting specific outcomes. The findings revealed that this coordinated team approach provided increased support for the new graduate, reduced the stress and workloads on the preceptors, whilst promoting confidence in the new starters and preventing conflict between preceptors and preceptees. The Coordinator’s role was shown to be an effective and crucial component in the Coordinated Team Preceptorship Model (CTPM) and findings illustrated that a team preceptorship model is not sustainable without a Coordinator.  相似文献   
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