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101.
OBJECTIVES: To categorize the radiological presentation of osteosarcoma of the jaws. METHODS: Conventional radiographs and CT scans of nine patients with histologically proven osteosarcoma were reviewed. RESULTS: Five patients were men and four women, aged between 20 and 51; four lesions were in the maxilla and five in the mandible. Three radiological presentations of osteosarcoma of the jaw were identified. The first was radiolucent, characterized by a total absence of bone formation within the tumour. The second had a mottled appearance with small areas of amorphous ossification separated by non-ossified tumour tissue. The third, with lamellar ossification, was typically characterized by bony plates irradiating from a focus like a 'sunburst'. CONCLUSION: Radiological diagnosis of osteosarcoma of the jaw can be difficult because of its variable appearance. CT is particularly useful. 相似文献
102.
High-frequency ultrasound (US) is an efficient, rapid and inexpensive altenative to magnetic resonance imaging (MRI) for investigation
of diseases in the soft tissues of the wrist and hand. US allows detection of foreign bodies and the reliable identification
of a variety of traumatic lesions affecting tendons, annular pulleys, ligaments, vessels and nerves. Inflammatory diseases
of tendons, including acute and chronic tenosynovitis and some degenerative conditions in the wrist and hand, can also be
diagnosed. In entrapment neuropathies, US is able to identify nerve shape changes and possible extrinsic space-occupying lesions
that may cause nerve compression within the tunnels. In patients with localized swelling of the hand or wrist, US is able
to assess the presence of an expansile lesion and to characterize its nature in most cases. The objective of this article
is to review the main findings and the primary indications of US in the investigation of disorders of the hand and wrist.
Received: 10 September 1998 Accepted: 24 November 1998 相似文献
103.
Ferrarese C Zoia C Pecora N Piolti R Frigo M Bianchi G Sala G Begni B Riva R Frattola L 《Journal of neural transmission (Vienna, Austria : 1996)》1999,106(7-8):685-692
Summary. Defects in mitochondrial enzymes have been found not only in substantia nigra, but also in platelets from Parkinson's Disease
(PD) patients, suggesting a systemic impairment of energy metabolism. Since platelets present an energy-dependent glutamate
uptake similar to that described in central nervous system, glutamate uptake was determined in platelets from 34 PD patients
and 21 age-related normal controls, as Na+-dependent [3H]glutamate influx; glutamate level was also analyzed by reverse-phase HPLC. A 50% reduction of glutamate uptake (p < 0.001)
was observed in idiopathic PD patients, respect to controls and secondary parkinsonian syndromes. The decrease correlated
with the severity of PD, measured by the UPDRS (r = −0.54; P < 0.05). Glutamate level was increased in platelets of PD patients,
but was not correlated to the uptake decrease. Both phoenomena may be explained by the modifications of mitochondrial enzymes
described in platelets, which could be used as a peripheral model of glutamatergic function in PD.
Received October 7, 1998; accepted January 7, 1999 相似文献
104.
BACKGROUND: At present video thoracoscopy is a primary diagnostic procedure in the diagnosis of pleural diseases, particularly when pleural effusions have unknown origin. METHODS: In this article the personal experience is reported about 20 patients in which video thoracoscopy was very important in the diagnosis of pleural effusions. RESULTS: Thoracoscopy permits to explore the thoracic cavity and to do a lot of biopsies. Video thoracoscopy, made it possible to diagnose 10 cases of malignant mesothelioma, 2 cases of pleural metastases (renal mts and mammary mts) and 8 cases of inflammatory diseases. CONCLUSIONS: At last, is laid on the contribution of video thoracoscopy to determine the stage of malignant mesothelioma. 相似文献
105.
A benign neoplastic lesion of the skin originating from cystic proliferation of apocrine secretory glands is defined as an apocrine hidrocystoma or cystadenoma. The tumor usually occurs in adults as a solitary cystic lesion; it is commonly found on the periorbital region, neck, upper torso and limbs. The case presented is unusual because of the age of the patient--cystadenoma is very rare in childhood--and the localization of the lesion. From a literature review and to the best of our knowledge, a scrotal cyst has never been previously described. Surgical excision is the treatment of choice since the lesion does not tend to recur. 相似文献
106.
F P Mattioli A Cagnazzo F Razzetta C Bianchi E Varaldo A Campagna A Percivale 《Minerva chirurgica》1999,54(7-8):471-476
BACKGROUND: To assess which factors determined conversion to laparotomy in patients undergoing laparoscopic elective cholecystectomy. Setting: department of General Surgery. University of Genoa. Italy. METHODS: Two hundred sixty-four consecutive laparoscopic cholecystectomies were performed in our Department. Interventions: laparoscopic cholecystectomy was performed according to Dubois's technique. Duration of the procedure was not considered a reason for conversion. RESULTS: 121 patients showed "difficult intraoperative situations" with further conversion risk factor. Conversion to laparotomy was necessary in 11 patients (4.16%). Five patients underwent conversion in the first 50 cases (10%), while six in the last 214 (2.8%). We had to convert to open cholecystectomy only in eleven patients, despite the high rate of technical difficulties and anatomic anomalies even in cases which, in the past, represented a contraindication to this kind of technique. The use of new instruments and new surgical techniques has reduced to only factors of increased risk in those situations that in the past were considered as contraindications to laparoscopic cholecystectomy. CONCLUSIONS: Conversion to open cholecystectomy is based on the surgeon's decision and the safety should be the main consideration in performing laparoscopic cholecystectomy. The use of a careful dissection could avoid the conversion in many patients. 相似文献
107.
Hyponatremia in neurosurgical patients 总被引:12,自引:0,他引:12
Bianchi A Cavallo R Imeneo MR Manno E Riva M Terragni P Vacca R 《Minerva anestesiologica》1999,65(11):807-810
Hyponatremia played an essential role in this case, determining the rapid transition from consciousness to a state of coma in female patient who had just come through the critical phase of intensive care. This circumstance underlines the importance of a correct water balance in patients undergoing neurosurgery, as well as a knowledge of the inappropriate antidiuretic hormone secretion (SIADH) syndrome responsible, either alone or in association, for the genesis of severe hyponatremia. In the differential diagnosis of hyponatremia, it is important to recall the role of an often mistaken syndrome (cerebral salt wasting syndrome) characterized by the secretion of a natriuretic factor that has still not been clearly identified. 相似文献
108.
Vaccination of pigs against pseudorabies virus with plasmid DNA encoding glycoprotein D 总被引:1,自引:0,他引:1
Haagmans BL van Rooij EM Dubelaar M Kimman TG Horzinek MC Schijns VE Bianchi AT 《Vaccine》1999,17(9-10):1264-1271
We analysed the ability of a plasmid carrying the gene encoding glycoprotein D (gD) of pseudorabies virus (PRV) to induce humoral and cell-mediated immune responses and assessed the protection provided by PRV-gD DNA vaccination against challenge infection with PRV. Immunization with plasmid PRV-gD induced neutralizing antibodies and lymphocyte proliferative responses both in mice and pigs. Moreover, when challenged with virulent PRV six weeks following the last immunization, PRV-gD DNA vaccinated pigs excreted virus for a significantly shorter period and showed less clinical symptoms than pigs vaccinated with a control plasmid. Thus, in the target animal, DNA vaccination with PRV-gD DNA induces protective immunity against challenge infection. 相似文献
109.
BACKGROUND: The prerequisites necessary for attributing lung carcinoma to asbestos, represent a controversial issue. METHODS: Three parameters (occupational history, pleural plaques, and lung asbestos bodies) were investigated in 414 consecutive cases of lung carcinoma, examined at necropsy at the Hospital of Monfalcone, Italy. Occupational data were obtained from the patients' relatives by personal or telephone interviews. Pleural plaques were classified into three classes (small, moderate, large). Routine lung sections were examined for asbestos bodies in all cases; isolation and counting were performed in 408 cases. RESULTS: The series included 353 men, and 61 women, aged between 38 and 97 years. The male patients had worked in industries in 74% of cases (60% in shipbuilding). Men showed pleural plaques in 82% of cases (moderate or large plaques in 58.7%). Asbestos bodies were observed in routine lung sections in 34.8%, and in 31% exceeded the value of 5,000 bodies per gram of dried tissue. Among women the principal features were: history or domestic exposure to asbestos in 36% of the cases, prevalence of pleural plaques 34% (moderate or large plaques 15%), asbestos bodies in routine lung sections in 3.3% and there was no case with an asbestos body burden over 5,000/g. The fraction of asbestos-related carcinomas among male patients varied between 24.7 and 61%, depending on the criteria used for attribution. CONCLUSIONS: Different criteria indicated about 60% of the present lung carcinomas among men as plausibly attributable to asbestos. 相似文献
110.
Salvadori S Guerrini R Balboni G Bianchi C Bryant SD Cooper PS Lazarus LH 《Journal of medicinal chemistry》1999,42(24):5010-5019
Twenty N- and/or C-modified Dmt-Tic analogues yielded similar K(i) values with either [(3)H]DPDPE (delta(1) agonist) or [(3)H]N, N(Me)(2)-Dmt-Tic-OH (delta antagonist). N-Methylation enhanced delta antagonism while N-piperidine-1-yl, N-pyrrolidine-1-yl, and N-pyrrole-1-yl were detrimental. Dmt-Tic-X (X = -NHNH(2), -NHCH(3), -NH-1-adamantyl, -NH-tBu, -NH-5-tetrazolyl) had high delta affinities (K(i) = 0.16 to 1 nM) with variable mu affinities to yield nonselective or weakly mu-selective analogues. N, N-(Me)(2)Dmt-Tic-NH-1-adamantane exhibited dual delta and mu receptor affinities (K(i)delta = 0.16 nM and K(i)mu = 1.12 nM) and potent delta antagonism (pA(2) = 9.06) with mu agonism (IC(50) = 16 nM). H-Dmt-betaHTic-OH (methylene bridge between C(alpha) of Tic and carboxylate function) yielded a biostable peptide with high delta affinity (K(i) = 0.85 nM) and delta antagonism (pA(2) = 8.85) without mu bioactivity. Dmt-Tic-Ala-X (X = -NHCH(3), -OCH(3), -NH-1-adamantyl, -NHtBu) exhibited high delta affinities (K(i) = 0.06 to 0.2 nM) and elevated mu affinities (K(i) = 2.5 to 11 nM), but only H-Dmt-Tic-Ala-NH-1-adamantane and H-Dmt-Tic-Ala-NHtBu yielded delta receptor antagonism (pA(2) = 9.29 and 9.16, respectively). Thus, Dmt-Tic with hydrophobic C-terminal substituents enhanced mu affinity to provide delta antagonists with dual receptor affinities and bifunctional activity. 相似文献