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991.
A patient with end-stage renal failure, two previously failed kidney transplants and high serum lymphocytotoxic antibody levels was transplanted electively with an ABO-mismatched, HLA-identical kidney from his sibling. Immunosuppression consisted of pretransplant splenectomy and plasma exchange, followed by rabbit antithymocyte serum, azathioprine, prednisone and plasma exchange in the early post-transplant period. He is now 3 years post-transplant with normal renal function on conventional immunosuppressive therapy. This case, and a review of the literature, suggest that ABO blood group incompatibility need not be an absolute barrier to successful kidney transplantation. ABO incompatible kidney transplantation may be a potentially fruitful area for further research as the demand for donor organs continues to outstrip the supply.  相似文献   
992.
Extensor mechanism complications following total knee arthroplasty   总被引:5,自引:0,他引:5  
Extensor mechanism complications following 281 knee arthroplasties that included patellar resurfacing, performed by two surgeons in one hospital over a 6-year period, were reviewed. The mean follow-up period was 42 months. There were 28 (10%) extensor mechanism complications: 3 quadriceps tendon ruptures, 5 patellar fractures, 4 patellar tendon ruptures, 11 recurring patellar subluxations, 4 cases of patellar pain, and 1 malrotated patella. Nine (3%) required further surgery. Surgical technique may have contributed to the tendon ruptures; patellar fractures occurred mainly in patients who had rheumatoid arthritis. Patients with patellar subluxation had abnormal preoperative valgus deformities of their knees and presented with this subluxation problem an average of 4 months after surgery, but it appeared to cause them less discomfort with time. Patellar resurfacing as part of a knee arthroplasty procedure is recommended but should be performed with care to the integrity and vasculature of the extensor mechanism.  相似文献   
993.
Rotator interval lesion   总被引:5,自引:0,他引:5  
Arthrography and surgical exploration reveal the pathogenesis of a painful shoulder syndrome characterized by inferior instability in the rotator interval (RI). The RI is the space between the subscapularis and the adjacent supraspinatus interval. Two types of RI lesions can be identified. Type I, a contracted state, is characterized by inflammatory changes in superficial bursal area. In Type II, an unstable condition is associated with extensive inflammation of deeper tissues in the RI. In a series of 101 patients, including 106 shoulders with RI lesions, surgical repair of the RI was performed with the shoulder in an externally rotated position. This position ensured a close fit of the supraspinatus and the subscapularis attachments. Of 78 shoulders evaluated in a follow-up study, 96% were graded good or excellent, and 4% poor. This investigation presents evidence for the importance of diagnosis and treatment of RI lesions in patients with persistent pain in the shoulder.  相似文献   
994.
Two methods of separating human sperm were compared using twenty-two semen samples. The sperm were separated by a swim-up technique or by self-migration on a Percoll gradient followed by medium change. After separation, the sperm obtained were assessed for progressive motility, ATP content, energy charge index ([ATP + 0.5 ADP]/[ATP + ADP + AMP]) and morphology. In general, and especially for semen samples containing less than 20 X 10(6) sperm/ml, separation by Percoll gradient selected sperm that were superior to those separated by the swim-up technique. The relatively high energy charge index (greater than 0.8) showed that the sperm tolerated the separation conditions well. It is suggested that self-migration on a Percoll gradient should prove useful for obtaining sperm of high quality.  相似文献   
995.
The objective of this article is to describe histological methods currently used to study ovarian physiology that may have applicability to reproductive toxicology. Histologic techniques are, for the most part, inexpensive and easy to perform. Many of these techniques require little equipment and can be readily implemented in small laboratories. The resulting histological preparations are permanent, can be used over again for several different types of analyses, and provide objective, quantifiable endpoints. These techniques have been extremely useful for studying the ovary.  相似文献   
996.
Effects of human recombinant TNF on the tumor blood vessels and on the thrombus formation were investigated in relation to its mode of antitumor action against Meth-A sarcoma transplanted in BALB/c mice. The extent of the blood vessel lesion was evaluated by using transparent chamber placed in the mouse skin. Bleeding, hyperemia and congestion were observed at 1-2h, 4-6h and 24h after TNF (1 X 10(4)U/mouse) administration, respectively. In contrast, no histological changes in the normal blood vessels were observed microscopically following TNF injection. Thrombus formation was evoked in the tumor vessels 4h after TNF injection. However, when thrombus formation was prevented by heparin, no difference was observed among antitumor action of TNF against Meth-A fibrosarcoma necrotic response and the rate of complete cure. These results suggest that the direct effects of TNF causing lesions in the tumor blood vessels plays an important role in its antitumor action.  相似文献   
997.
998.
999.
Surgically-obtained tissue specimens from 41 patients with ventricular aneurysm were studied electron microscopically. The tissue from the resected aneurysms showed substantially varied morphological differences. In some, there were extensive regions of scar containing increased fibrotic material and few cells, in others there were also larger contiguous regions of myocardium with an essentially normal appearance. In the preserved myocardial regions, the cardiac cells showed moderate hypertrophy. There was an increase in contractile substance in parallel with an increase in mitochondria and enlargement of the nucleus with frequent waves and invaginations in the cell membrane. The cells at the marginal regions between fibrous tissue and preserved myocardium were frequently isolated from adjacent cells. In particular, when the isolated cells were completely surrounded by fibrous tissue, clear degeneration was apparent. These cells showed mainly a fibrillolysis with dissolution of the cross-bands and loss of the entire contractile apparatus. In compensation, occasionally there was proliferation of other cell structures, especially the free sarcoplasmatic reticulum. The hypertrophy of the still intact myocardial cells is considered compensatory for the infarct-incurred loss of tissue. The degenerative appearance is mainly attributable to fibrous tissue invasion. The diminished oxygen supply, compromised or abolished impulse conduction, loss of function and passive stretch during systole may be regarded as causes of the degeneration.  相似文献   
1000.
Cibenzoline, a new class I antiarrhythmic drug, was compared with quinidine in an open crossover study of 20 patients with frequent (greater than 30/hr) premature ventricular depolarizations (PVDs). Eight patients treated with cibenzoline experienced more than 75% reduction in PVD frequency. Cibenzoline completely suppressed ventricular couplets in eight of 17 patients and inhibited ventricular tachycardia (VT) in four of 13 patients. Only four patients (20%) responded to quinidine with a similar reduction in PVDs. Quinidine completely suppressed ventricular couplets in eight of 17 patients and episodes of VT in six of 13 patients. Cibenzoline prolonged PR, QRS, and QTc intervals. Eight patients who had shown more than a 75% reduction of PVDs were treated with cibenzoline for an extended period. At the end of three months, only five of eight patients continued to have 75% or greater reduction of PVDs. At the end of six and 12 months, four of five patients continued to have 75% or greater reduction of PVDs. Cibenzoline was similarly effective in suppressing complex arrhythmias. Thus, cibenzoline was only slightly superior to quinidine in suppressing ventricular arrhythmias. With long-term use of cibenzoline, significant PVD suppression was noted at the end of three months but not afterward.  相似文献   
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