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961.
Although involvement of the liver is common in systemic amyloidosis, clinical manifestations of hepatic dysfunction and liver biochemical abnormalities are often absent or only mild. Here we report on a patient with primary amyloidosis and rapid development of liver failure, who was successfully treated by liver transplantation. The patient is a 61-year-old Swedish man who was admitted to the local hospital for spontaneous rupture of the spleen. Before admission, he had suffered from diffuse upper abdominal discomfort, diminished appetite, and had lost 15 kg in 6 months. Shortly after splenectomy, he developed cholestatic liver failure with moderate hepatomegaly, jaundice, ascites and hyponatremia. Over a period of 3 weeks his liver failure progressed, renal function deteriorated rapidly, and he developed encephalopathy. Liver transplantation was performed on the 35th day after splenic rupture. Histological examination revealed extensive deposits of amyloid in the spleen and liver. ¶N-terminal amino acid sequence analysis of the amyloid protein, purified from the patient's native liver, revealed an AL protein of kappa ¶I-type origin. The postoperative course was uncomplicated, apart from one episode of sepsis and one course of treatment for acute rejection. He was discharged from hospital with normal liver function and good kidney function. One year after surgery, he was in good condition, with normal liver function. However, a liver biopsy taken at the same time showed de novo amyloid deposits in the grafted liver. We conclude that liver transplantation may be indicated as a life-saving procedure in rapidly progressing hepatic amyloidosis with cholestatic jaundice, although the underlying disease has not changed.  相似文献   
962.
Objective To investigate if low dose total body irradiation (TBI, 6.0-9.0 Gy) combined with intensified chemotherapy followed by autologous peripheral blood stem cell transplantation results in better survival in children with refractory leukemia or solid tumors. Methods Twenty-one children with malignant tumors were included in this study.There w ere 14 males and 7 females aged 3.5-12 years.Underlying disease included high -risk acute lymphoblastic leukemia (ALL, CR(1) in 3 children and CR(2) in 5 ch ildren), acute myeloblastic leukemia (AML, 9 children), non-Hodgkin’s lymphoma stage Ⅳ ( 2 children), and neuroblastoma stage Ⅳ (2 children).The peripheral hematopoi etic stem cells were collected six to eleven months after complete response, mob ilized with high dose chemotherapy alone or combined with GM-CSF or G-CSF.Th e conditioning regimen consisted of chemotherapy with two to three combinations of the following drugs: cyclophosphamide, arabinosylcytosine, McNU, etopside, an d Idarubicin on the basis ofTBI (6.0-9.0 Gy).A mean of (1.8±0.5) ×10(8)/kg autologous mononuclear cells were transplanted.The patients were followed up after transplantation. Results Severe bone marrow suppression occurred in all patients around day +7.Peripher al white blood cell count decreased to 0 in all patients at day +4.8±2.9, and platelet count decreased to less than 20×10(9)/L at day +9.0±2.6.Succ essful engraftment was achieved in 21 patients, but four died of infection at da y +17, +20, +31 and +67, respectively.Recovery of white blood cell (WBC) to 10×10(9)/L, absolute neutrophil count to 0.5×10(9)/L, platelet count to 20 ×10(9)/L occurred on 21±12, 26±13, and 27±10 days, respectively.During the follow up period, three patients relapsed at +5 months, +1.5 years, and +2 yea rs 10 months, respectively.One patient died of intracranial hemorrhage at +8 m onths.Thirteen patients had event-free survival for 2-12 years, with a mean o f 6.7±3.4 years.Conclusion Our preliminary data suggest that myeloablative therapy with low dose TBI (6.0 -9.0 Gy) combined with intensified chemotherapy followed by autologous periphe ral blood stem cell transplantation might be associated with favorable results i n children with refractory leukemia or solid tumors.  相似文献   
963.
OBJECTIVES: A new measuring technique for the determination of thermal diffusivity is proposed. Using this technique, the thermal properties of a few different dental filling materials were measured. METHODS: The proposed method for measurement of thermal diffusivity is based on the classical Angstr?m's method. The method exploits the propagation of a plane thermal wave generated by a Peltier's device in a cylindrical sample along its axis. The thermal diffusivity of the sample is calculated from the phase difference between harmonic components of temperatures measured at sample surfaces, perpendicular to the direction of thermal wave propagation. The estimated accuracy of measurement is typically about 10% for samples with low thermal diffusivity. The proposed method was used for the determination of thermal diffusivities of Achatit Bichromatic, Charisma and Dentimet dental filling materials. RESULTS: The measured thermal diffusivities were: 0.295(0.020)x10(-6)m(2)s(-1) for Achatit Bichromatic, 0.321(0.015)x10(-6)m(2)s(-1) for Charisma and 1.70(0.12)x10(-6)m(2)s(-1) for Dentimet. The thermal conductivities of these materials were also estimated. The results were compared with values obtained from independent constant flux measurements with marble as a reference material. SIGNIFICANCE: There are no standard techniques for the determination of the thermal properties of dental filling materials. Moreover, it is difficult to find the thermal diffusivity and the thermal conductivity of many of them. The method proposed in this paper allows the simple and accurate measurement of thermal diffusivity. Thermal parameters of dental filling materials should be compatible with the parameters of human teeth. Lack of thermal compatibility can cause not only patient discomfort but also mechanical stresses leading to microcracks.  相似文献   
964.
Spontaneous intracranial hypotension is characterized by orthostatic headaches in conjunction with reduced cerebrospinal fluid volume(CSF) and characteristic imaging findings. We report the clinical course of six consecutive patients with spontaneous intracranial hypotension who were followed between 4 months and 2.5 years. The characteristic orthostatic headaches were present in five patients. Diffuse pachymeningeal enhancement on brain magnetic resonance imaging (MRI) was evident in all cases. CSF detected elevated protein content in three of six patients. In only two of our six patients a first epidural blood patch resulted in complete symptom resolution lasting 4 months and 1 year. Four patients received a second epidural blood patch and one patient also received a third. In four patients, follow-up brain MRI revealed re-occurrence of the typical MRI features and all of them suffered from orthostatic symptoms at this time. Only four patients are free of complaints after an average follow-up period of 10 months. Symptom relief within 7 days from an epidural blood patch is accepted to be diagnostic for spontaneous intracranial hypotension. However, our data illustrate that the clinical course of the syndrome is very unstable and the epidural blood patch is less effective than widely accepted.  相似文献   
965.
966.
Wrist injuries causing coincident disruptions of the scapholunate and lunotriquetral ligaments commonly result in perilunate dislocations. This article (1) describes our management of eight patients with wrist pain after coincident scapholunate and lunotriquetral ligament disruptions in the absence of perilunate dislocation; and (2) reports the results of biomechanical testing of some of the extrinsic and intrinsic wrist ligament and interprets these data to explain the injury seen clinically. The diagnosis of ligament failure was made on the basis of history, physical examination, arthrography and surgical exploration. Surgical treatment of seven patients consisted of concomitant scapho-trapezio-trapezoid fusion and lunotriquetral fusion. Three of seven patients were free of pain, two had pain only at the extremes of motion, and two required additional surgery. Biomechanical analysis of the scapholunate and lunotriquetral ligaments and two extrinsic wrist ligaments, the radiolunotriquetral and the radioscaphocapitate, confirmed the clinical suspicion that the intrinsic ligaments could be completely disrupted while the extrinsics are only partially injured. Such a scenario could account for the residual stability that prevents the development of perilunate dislocations. Coincident disruption of the scapholunate and lunotriquetral ligaments in the absence of perilunate dislocation is an unusual injury. Treatment with lunotriquetral fusion and scapho-trapezio-trapezoid fusion restored functional use in five of seven wrists while maintaining wrist motion.  相似文献   
967.
A deviation from physiological osmolality (300 mOsm/kg H2O) can lead to genotoxic effects. A 30-min treatment of V79 hamster cells with hy-potonic sodium chloride of 60 mOsm/kg H2O or with diluted culture medium of the same osmolality induces extraordinarily high frequencies of chromosomal aberrations. In this study, multiple fixation times over a 24-hr period were used to identify cells in various stages of the cell cycle at the time of treatment and to find out whether or not hypotonic conditions are able to induce aberrations in all cell cycle stages. Because of the aberration pattern observed, it is suggested that hypotonic treatment acts as an S-independent agent, like X-rays or restriction endonucleases. Whether the aberrations originate from directly induced DNA damage or from a release of DNase after lysosomal breakdown is discussed.  相似文献   
968.
This paper is a review of the medical concerns pertinent to dental care and a preliminary study of dental findings of the sickle cell anemia (SS) patient. The dental characteristics observed in 21 dental patients with SS are described. Radiographic findings included "stepladder" trabeculae pattern (70%), enamel hypomineralization (24%), calcified canals (5%), Increased overbite (30–80%), and increased overjet (56%). Comparisons are made with other studies of the sickle cell patient, and the need for further study is suggested.  相似文献   
969.
Captopril, an angiotensin converting enzyme inhibitor, was evaluated for a potential antidepressive activity in several animal models. The drug administered in doses of 3-30 mg/kg ip neither affected the reserpine- or apomorphine-induced hypothermia in mice nor reduced the immobility time in the forces swimming test in mice and rats. Moreover, captopril administered repeatedly (10 mg/kg ip, twice daily for 14 days) neither changed the density or affinity of cortical beta-adrenoceptors nor modified the nomifensine-induced locomotor hyperactivity in rats. These results suggest that captopril has no antidepressant-like activity in animal models.  相似文献   
970.
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