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91.
Healing of a tendon graft to a bone tunnel is slower than the healing of a bone plug. Therefore, the device chosen for hamstring fixation may need to maintain its strength and stiffness longer than the device chosen for bone-tendon-bone fixation. We evaluated, in an extraarticular ovine model, how 4 and 12 weeks of implantation affect the strength of a tendon graft fixed to bone with the Evolgate. The long digital extensor tendon was transplanted and fixed with the Evolgate into a 30-mm long, 8 mm diameter bone tunnel drilled in the tibial metaphysis of both posterior limbs of 15 skeletally mature Suffolk sheep. Immediately after implantation, and 4 and 12 weeks later, biomechanical cyclic load tests in 50 N increments were performed until failure to evaluate the ultimate failure load (UFL). Histological analysis was also performed at 4 and 12 weeks. Biomechanical tests revealed a UFL of 339±120 N at time 0, and increases to 635±19 N (4 weeks) and to 867±80 N (12 weeks). The differences between all 3 groups were significant (p<0.001, paired t test). The histological evaluation showed a layer of cellular, fibrous tissue between the tendon and the bone, along the length of the bone tunnel; this layer progressively matured and reorganized during the healing process. The collagen fibers that attached the tendon to the bone resembled Sharpey’s fibers. The strength of the interface significantly and progressively increased between weeks 4 and 12 after transplantation, and was associated with a degree of bone ingrowth noted histologically. The use of the Evolgate seems not to interfere with the bone ingrowth after implantation, allowing an improvement in strength of the bonetendon- device complex.  相似文献   
92.
Optimum conditions for the spectrophotometric determination of pyrimidine derivatives in biological fluids of humans are determined. This method has been used for the investigation of the pharmacokinetics of the new immunomodulant ximedone in humans, dogs, and rats upon administration of the drug in different ways. Interspecific relationships of the key parameters of ximedone pharmacokinetics are established. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 7, pp. 5–8, July, 2006.  相似文献   
93.
OBJECTIVE: A relationship between brain atrophy and delta rhythmicity (1.5-4 Hz) has been previously explored in Alzheimer's disease (AD) subjects [Fernandez A, Arrazola J, Maestu F, Amo C, Gil-Gregorio P, Wienbruch C, Ortiz T. Correlations of hippocampal atrophy and focal low-frequency magnetic activity in Alzheimer disease: volumetric MR imaging-magnetoencephalographic study. Am J Neuroradiol. 2003 24(3):481-487]. In this study, we tested the hypothesis that such a relationship does exist not only in AD patients but also across the continuum of subjects with mild cognitive impairment (MCI) and AD. METHODS: Resting, eyes-closed EEG data were recorded in 34 MCI and 65 AD subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. Cortical EEG sources were correlated with MR-based measurements of lobar brain volume (white and gray matter). RESULTS: A negative correlation was observed between the frontal white matter and the amplitude of frontal delta sources (2-4 Hz) across MCI and AD subjects. CONCLUSIONS: These results confirmed for the first time the hypothesis that the sources of resting delta rhythms (2-4 Hz) are correlated with lobar brain volume across MCI and AD subjects. SIGNIFICANCE: The present findings support, at least at group level, the 'transition hypothesis' of brain structural and functional continuity between MCI and AD.  相似文献   
94.
95.
The optimum extraction conditions for obtaining a new mixed plant preparation (tanton) have been determined and its phytochemical composition has been studied. The antistressor activity of tanton has been established in experiments on white rats. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 11, pp. 42–46, November, 2007.  相似文献   
96.
The pharmacokinetics of isonicotinic acid hydrazide upon joint administration with the immunomodulant ximedone has been investigated. Ximedone influences the genetically determined parameters of the isonicotinic acid hydrazide pharmacokinetics. The dose-dependent and temporal schedules of ximedone administration in humans are established, which favor the induction of acetylation processes in patients. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 3, pp. 3–6, March, 2006.  相似文献   
97.
The authors present a retrospective study of 66 infected cases in their series of limb salvage surgery performed from January 84 to August 92. Special emphasis was given to the alternative techniques of treatment in infection. In 85% of the cases healing was achieved, however removal of the implant and amputation are still frequent occurrences. Time to recovery is very demanding.  相似文献   
98.
The relationships between gastric pH and Helicobacter pylori infection were studied in 37 consecutive subjects affected with nonulcer dyspepsia. Each underwent esophagogastroduodenoscopy with multiple gastric biopsies for both H. pylori and histologic assessment, and 24-hr antral pH monitoring. H. pylori was harbored by 59.5% of the subjects with whole gastric spread of infection in all but one patient. Histologic gastritis was shown in 70.3% of the subjects. H. pylori was strongly associated with gastritis, both antral nonatrophic and multifocal atrophic. The ranges of 24-hr pH values were 1.3-6.9 in the H. pylori-positive and 1.2-6.8 in the H. pylori-negative group. Differences in pH values between the two groups were not significant. Moreover, the mean percent time duration of pH above 2, 4, and 6 did not significantly differ between the two groups. Therefore, this study has shown that chronic H. pylori infection is not related to luminal gastric pH.  相似文献   
99.
Giant cavernous hemangiomas: Diagnosis and surgical strategies   总被引:4,自引:0,他引:4  
From January, 1972 to June, 1989, 51 patients with liver hemangiomas (32 females and 19 males, mean age 35 years) were evaluated for surgical treatment. Diameters of the masses were 5 cm to 20 cm (median 8.5 cm). Nine of the patients had already been treated for cancer. Twenty-two (43.1%) of the 51 patients were symptomatic and 29 (56.9%) patients were asymptomatic. In 34 patients (66.7%) a definite diagnosis of hemangioma was made by scintiscan and/or ultrasound and/or computed tomography and/or angiography while in the remaining 17 (33.3%) patients the diagnosis was uncertain. The most common indications for resection were the presence of a symptomatic angioma, a symptomatic mass with an uncertain diagnosis, and/or lack of a definite pre-operative diagnosis. Surgery was performed on 25 patients. Ten anatomic and 15 atypical resections or enucleations were performed. There were no postoperative deaths. Two further patients, operated for probable hemangioma, were found to have primary hepatic malignancies. In the 26 unresected patients, no complications were observed during follow-up. In 3 patients, hemangioma enlargement was detected by ultrasound, but there were no symptoms. As cavernous liver hemangiomas are now more reliably diagnosed and their natural history is usually uneventful, surgery can be avoided in most cases. However, when a non-resection policy is adopted, an exact diagnosis is essential in order to rule out primary or metastatic cancer. Surgical exploration and treatment should be limited to symptomatic or complicated cases as well as to patients with an uncertain diagnosis.
Resumen Cincuenta y un pacientes con hemangiomas del higado (32 mujeres y 19 hombres, edad promedio 35 años) fueron valorados en cuanto a tratamiento quirúrgico en el período enero 1972 a junio de 1989; el diámetro de las lesiones oscilo entre 5 y 20 cm (promedio 8.5 cm). Nueve de los pacientes ya habían sido tratados por cáncer; 22/51 (43.1%) estaban sintomáticos y 29/51 (56.9%) eran asintomáticos. En 34/51 (66.7%) se hizo el diagnóstico definitivo de hemangioma mediante escintigrafia y/o ultrasonido y/o tomografía computadorizada y/o angiografia, en tanto que en los otros 17 pacientes (33.3%) el diagnóstico resultó incierto. Las indicaciones más comunes para resección fueron: presencia de un angioma sintomático, una masa asintomática con diagnóstico incierto y/o ausencia de diagnóstico preoperatorio definitivo. Se practicó cirugía en 25/51 pacientes, habiéndose realizado 10 resecciones anatómicas y 15 resecciones atípicas o enucleaciones. No hubo muertes postoperatorias. Otros dos pacientes operados por probable hemangioma demostraron tener neoplasias malignas hepáticas primarias. En los 26 pacientes no resecados no se observaron complicaciones durante el seguimiento; en tres casos se detectó ensanche del hemangioma en el examen con ultrasonido, pero no se presentaron síntomas. Puesto que actualmente los hemangiomas cavernosos del hígado pueden ser diagnosticados con mayor certeza y puesto que su historia natural generalmente está libre de complicaciones es posible evitar la cirugía en la mayoría de los casos. Sin embargo, cuando se pretenda adoptar una política de no resección es esencial establecer el diagnóstico exacto para excluir la posibilidad de un cáncer primario o metastásico. La exploración y el tratamiento quirúrgicos debe permanecer limitados a los hemangiomas sintomáticos o complicados, y en ningún caso deben significar riesgo para el paciente.

Résumé De Janvier 1972 à Juin 1989, 51 patients ayant un hémangiome du foie (32 femmes et 19 hommes, âge moyen 35 ans) ont été examinés en vue d'une exérèse chirurgicale. Le diamètre de la lésion variait entre 5 et 20 cm (médiane = 8.5 cm). Neuf des patients avaient déjà été traités pour un cancer; 22/51 (43.1%) étaient symptomatiques alors que 29/51 (56.9%) étaient asymptomatiques. Chez 34/51 patients (66.7%), le diagnostic définitif d'hémangiome a été confirmé par scintigraphie et/ou échographie et/ou tomodensitométrie, alors que chez les 17 autres (33.3%), le diagnostic était uncertain. Les indications d'une résection les plus fréquentes étaient: la présence d'un angiome symptomatique, une masse symptomatique avec un diagnostic uncertain, et/ou absence de diagnostic définitif préopératoire. Vingt-cinq des 51 patients ont été opérés. Il y a eu 10 résections anatomiques et 15 résections atypiques ou énucléations. Il n'y a pas eu de mortalité postopératoire. Deux autres patients, traités pour ce que l'on soupçonnait être une probalbe hémangiome du foie, avaient en fait un cancer hépatique. Chez les 26 patients non résequés, il n'y avait pas eu de complication. Chez trois patients, on a mis en évidence une augmentation de volume par l'échographie, mais ces modifications ne s'accompagnait d'aucune symptomatologie. Comme on peut faire le diagnostic d'hémangiome carverneux du foie avec plus de fiabilité qu'avant, et comme on sait que leur histoire naturelle est généralement bénigne, on peut le plus souvent surseoir à l'exérèse chirurgicale. Cependant, il importe de toujours faire le diagnositc avec certitude, de façon à éliminer un cancer primitif ou sécondaire du foie.
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100.
The incidence of invasive fungal infection is increasing especially in the field of transplantation, affecting as many as 50% of bone marrow transplant (BMT) patients with neutropenia and 5-20% of solid-organ transplant (SOT) recipients. Fusarium species are soil saprophytes and plant pathogens. They may cause superficial mycoses or important opportunistic infections in patients with bone marrow suppression and neutropenia, they have been rarely described in solid organ recipients, and up to now there have been no reports of such infection in isolated liver transplanted patients. We describe a case of disseminated Fusarium solani infection with hepatic localization in a liver transplanted patient that resolved with the administration of amphotericin B. Our observation confirms that Fusarium spp. are emerging pathogens that may most frequently affect not only BMT patients and patients with hematological malignancies, but also SOT patients. They may cause both localized and disseminated infection. In conclusion, Fusarium spp. etiology should be considered in the context of infectious diseases following liver transplantation.  相似文献   
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