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991.
Gallstone dissolution   总被引:2,自引:0,他引:2  
Many methods are available for gallstone dissolution, including oral bile salts; cholesterol solvents such as mono-octanoin or methyl tert-butyl either; and calcium or pigment solvents such as EDTA and polysorbate. Which of these approaches will be appropriate for an individual patient depends on the type of stones; whether they are in the gallbladder or the bile ducts; whether access to the biliary tree is available; the patient's age and general medical condition; and the availability of necessary expertise. In the US, both chenodeoxycholate and ursodeoxycholate are now available. Ursodeoxycholate is more expensive but appears to produce fewer side effects and may be more efficacious. These agents are most effective in thin women with small floating, radiolucent cholesterol stones in a functioning gallbladder. Only about half of the small subset of patients will experience partial or complete dissolution of stones within a year. Stone recurrence and the potential toxicity of long-term therapy are problems with this approach. Therefore, for most patients, cholecystectomy, either in the traditional fashion or using a laparoscopic approach (see article later in this issue by Gadacz et al), is the most cost-effective and perhaps the safest option. Intragallbladder instillation of methyl tert-butyl ether probably will be applicable only to a small subset of patients, and treatment is likely to be followed by a high recurrence rate. In patients with retained common duct cholesterol stones and access to the biliary tree, mono-octanoin therapy is advantageous in that it can be initiated as soon as cholangiography demonstrates no extravasation. In properly selected patients, a 90% success rate with this technique can be expected within 7 days.  相似文献   
992.
Patients on long-term haemodialysis suffer from dialysis arthropathy due to the deposition of dialysis amyloid. We investigated the use of 99Tc-labelled methylene diphosphonate bone scans in 17 patients as a possible in vivo diagnostic technique. In most clinically affected joints, with the exception of shoulders and hands, there was increased radioisotope uptake consistent with uptake by periarticular bone. In addition, we describe intense soft-tissue uptake around some clinically affected large joints. In contrast, control groups of patients on haemodialysis without arthropathy and patients without renal failure did not have increased uptake. A semi-quantitative scale of uptake was devised, and the following correlations were significant: pain perception and isotope uptake score in the ankles and feet, and the number of radiological lesions and isotope uptake scores in the wrists and knees. The following sites where the radioisotope might bind in the affected joints are proposed: amyloid deposits, areas of soft-tissue calcification, or areas of increased bone turnover. It is concluded that whereas the scanning technique cannot make a definite diagnosis of amyloid and, therefore, cannot be expected to supersede histological diagnosis, it is a useful adjuvant investigation, of particular importance in those patients unable or unwilling to undergo biopsy.  相似文献   
993.
Eleven patients with lunatomalacia were treated by excision of the lunate and instillation of liquid silicone. The silicone vulcanised and formed an in-situ molded prosthesis. The patients were reexamined after a mean of 7.1 years. Four patients were pain-free and two had pain only at work; three had not been improved by the operation and two had undergone arthrodesis. The patients with good results all belonged to group IV pre-operatively. Surprisingly, no patient showed any sign of silicone synovitis, although all the prostheses except one had either fractured or deformed. The reasons for this are discussed and the indications for the operation established.  相似文献   
994.
We retrospectively reviewed our experience with immediate breast reconstruction in 103 consecutive patients with stage 0 or I breast carcinoma between May 1983 and April 1988. Two reconstructive techniques were used, that is, either tissue expansion with secondary prosthesis implantation (60%) or transverse rectus abdominis musculocutaneous (TRAM) flap (40%). Chemotherapy was administered in 22% of patients without delay or compromise. The mean length of follow-up is 30 months. The complication rate was equal for both groups (24%) with infection being most common in the group of patients with tissue expansion and partial flap necrosis being most common in the group of patients with TRAM flaps. Aesthetic results were superior with use of the TRAM flap. Our experience concurs with previous reports that documented satisfactory results with immediate breast reconstruction without compromising further therapy. We conclude that although the tissue expansion technique yields acceptable results, the TRAM flap yields superior aesthetic results in terms of both appearance and consistency.  相似文献   
995.
Summary This study explores the effects of a calcium-deficient diet on patterns of bone remodeling, and examines regional differences in the amount of bone lost. Skeletally mature female rabbits (n=6) were fed a calcium-deficient diet (0.10% Ca2+ and 0.50% P) for 14 weeks. A separate group of rabbits (n=4) were fed a maintenance diet (1.2% Ca2+ and 0.45% P). Bone mineral content, serum calcium, and serum phosphorus were measured each week during the experimental period. Following sacrifice, the L3 vetebra, femoral head, proximal tibial metaphysis, and tibial midshaft were analyzed histomorphometrically. Rabbits had 20% less vertebral bone after only 14 weeks of a calcium-deficient diet. As in human postmenopausal osteoporosis, bone loss in calcium-deficient rabbits occurs in the trabecular bone of the lumbar spine before that in the trabecular bone of the lower extremity. Calcium-deficient diets alone do not lead to increased osteoid volume or thickness. Because bone loss is relatively rapid and because the pattern of loss is similar in some respects to that found in humans, adult rabbits may provide an attractive model of calcium deficiency osteoporosis in a skeletally mature mammal in which remodeling is predominant over modeling.  相似文献   
996.
Summary Previous studies of Alcian blue-induced birefringence in adult avian cortical bone showed that a short period of intermittent loading rapidly produces an increased level of orientation of proteoglycans within the bone tissue. In the absence of further loading, this persists for over 24 hours. We have proposed that this phenomenon could provide a means for “capturing” the effects of transient strains, and so provide a persistent, constantly updated strain-related influence on osteocyte populations related to the bones' averaged recent strain history, in effect, a “strain memory” in bone tissue. In our present study, we use the Alcian blue-induced birefringence technique to demonstrate that proteoglycan orientation also occurs after intermittent loading of both cortical and cancellous mammalian bonein vivo andin vitro. We also show that the change in birefringence is proportional to the magnitude of the applied strain, and that the reorientation occurs rapidly, reaching a maximal value after only 50 loading cycles. Examination of electron micrographs of bone tissue after staining with cupromeronic blue allows direct visualization and quantification of the change in proteoglycan orientation produced by loading. This shows that intermittent loading is associated with a realignment of the proteoglycan protein cores, bringing them some 5 degrees closer to the direction of collagen fibrils in the bone matrix.  相似文献   
997.
Sixteen patients with stable chronic asthma participated in a double blind crossover study comparing the new inhaled long acting beta 2 agonist formoterol with salbutamol. Inhaled (n = 15) and oral steroid (n = 1) treatment were maintained at the same daily dose throughout the study. For four weeks the patients received either formoterol 24 micrograms twice daily or salbutamol 400 micrograms twice daily, plus additional puffs (with the same drug) when needed. Asthma symptoms, additional puffs of beta 2 agonist, peak expiratory flow (PEF), and side effects were recorded daily. During treatment with formoterol the patients used fewer additional puffs of beta 2 agonist, had better symptom scores, less disturbed sleep, more days without additional aerosol, and higher PEF both morning and evening than during salbutamol treatment. Thus formoterol 24 micrograms twice daily gave long lasting bronchodilatation and asthma symptoms were well controlled with regular twice daily administration.  相似文献   
998.
999.
We have investigated anemia in patients at different stages of the evolution of three chronic renal diseases: Balkan endemic nephropathy (BEN), chronic pyelonephritis (PN) and chronic glomerulonephritis (GN). A total of 88 patients with creatinine clearances from 9 to 118 ml/min and hemoglobin concentrations from 70 to 160 g/l were studied with regard to the relationship, if any, between erythropoietin production and the type and stage of nephropathy. Anemia in BEN was a particular focus of interest since it had been stated that in BEN, anemia precedes renal failure. Our data neither prove nor disprove this statement. A significant positive correlation between creatinine clearance and hemoglobin concentration was found in all three nephropathies, indicating that in the patients studied the severity of anemia increased with the impairment of renal function regardless of the underlying disease. Serum levels of immunoreactive erythropoietin were in the normal range in 54 patients, moderately increased in 20 and slightly decreased in 14. The erythropoietin level appears to be unrelated to the stage of renal failure or the type of nephropathy. The only exception was the subgroup where the patients with glomerulonephritis and normal renal function had increased serum erythropoietin levels and significantly higher parameters of red blood cell concentration than the patients from the same subgroup with tubulointerstitial nephropathies. In patients with severe renal failure and anemia, serum erythropoietin levels were inappropriately low for the degree of anemia, indicating that erythropoietin plays a role in the pathogenesis of the anemia.  相似文献   
1000.
We compared our standard NIH (extended incubation) crossmatch (XM) with antihuman globulin (AHG) and flow cytometry XMs and correlated the results with rejection episodes and graft survivals. For 89 CsA-Pred, primary renal allograft recipients, AHG and/or FCXM results did not improve on the NIH-XM-negative (NEG) graft survival results, whether testing pretransplant or historical (Hx) sera. Similarly, there was no association of a positive (POS) AHG or FCXM with increased rejection episodes in these primary recipients. However, for retransplant (Re-Tx) recipients a neg AHG or FCXM did discriminate fewer rejections and an improved graft survival compared with the NIH-XM-neg. results. The overall one-year graft survival for the 47 Re-Tx recipients studied herein was 66% (based on a neg pre-Tx NIH-XM). Pre-Tx AHG-NEG, Re-Tx recipients displayed an improved graft survival compared with NIH-XM NEG recipients (77% vs. 66%, P less than 0.05) and with AHG-POS recipients (77% vs. 47%, P less than 0.05). Similarly, pre-Tx, FCXM-NEG, Re-Tx recipients displayed improved graft survivals compared with NIH-XM-NEG recipients (83% vs. 66%, P less than 0.05) and FCXM-POS recipients (83% vs. 48%, P less than 0.05). Re-Tx recipients displaying a POS AHG and/or FCXM experienced a significantly greater number of rejections than NEG-XM recipients (P less than 0.05, respectively). The AHG and FCXM results correlated with rejections and graft survivals whether testing pre-Tx or Hx high-PRA sera. Re-Tx recipients who were AHG-XM-NEG but FCXM-POS, experienced more rejection episodes than recipients who displayed a negative XM reactivity for both AHG and FCXM (P less than 0.02), but with no resulting differences in graft survival. HLA matching, pre-Tx blood transfusions and PRA did not impact on these crossmatch and graft survival results. Use of AHG and/or FCXMs for Re-Tx, but not primary, recipients should help to improve graft survival for these high-risk recipients.  相似文献   
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