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61.
PURPOSE: To present a case of rapidly progressing traumatic cataract caused by posterior capsule rupture after nonpenetrating ocular injury, as well as a surgical procedure to safely implant the intraocular lens in such a traumatized eye. METHODS: In a 23-year-old man with traumatic cataract and posterior lens capsule rupture, a one-piece polymethylmethacrylate IOL was implanted before cataract extraction into the ciliary sulcus in front of the cataractous lens. Subsequently, the cataract was removed by pars plana lensectomy. RESULTS: The surgery and postoperative course were uneventful. Postoperative visual acuity was 20/20. CONCLUSION: We present a method of intraocular lens implantation in cases of rapidly progressing traumatic cataract caused by posterior capsule rupture after a blunt ocular trauma.  相似文献   
62.
Popliteal traumatic arteriovenous fistulas   总被引:1,自引:0,他引:1  
BACKGROUND: The purpose of this report is to analyze the clinical presentation, diagnosis, and outcome of surgical treatment in patients with popliteal arteriovenous fistulas (AVFs) in order to make trauma surgeons aware of the various issues patients with popliteal AVFs might present. METHODS: From 1991 to 2000, 49 patients were treated for traumatic AVF. Among these patients, seven suffered from popliteal AVF of various durations. The patients were men and ranged in age from 17 to 27 years, with a mean age of 22.4 years. The time from injury to admission to our institutions varied from 5 days to 2 years. A diagnosis of popliteal AVF was made after clinical examinations revealed thrill and bruit over the injury sites. The diagnosis was confirmed in four of the patients after they underwent angiography. Patients with long-standing popliteal AVF underwent cardiology examinations to check for signs of heart failure. All patients with popliteal AVF received surgical treatment. Five patients had major blood vessels reconstructed, one patient had a minor blood vessel ligated, and another patient had a minor blood vessel reconstructed. RESULTS: Five of the seven patients experienced no postoperative difficulties. No serious heart failure occurred; however, there were signs of cardiac overload in three of the five patients. The two remaining patients of the seven underwent leg amputations. However, one of the two patients had a gangrenous foot at admission to our institution, and vascular reconstruction on the other patient was unsuccessful. For all seven patients, the average hospital stay in the vascular surgery department was 16.2 days and the follow-up ranged from 2 to 44 months, with a mean of 21.5 months. CONCLUSION: Trauma of the popliteal space requires special attention, since blood vessel injuries in that zone might result in serious complications. Popliteal traumatic AVFs result in a high rate of leg amputation and long-standing fistulas produce cardiac overload. The presence of thrill and bruit over the injury site should alert the examiner to consider the existence of AVF. Angiography is a reliable diagnostic tool, and should be used in all vitally stable patients. Surgical or nonsurgical closure of AVF will prevent local and systemic complications that might be irreversible in long-standing fistulas.  相似文献   
63.
The first case of the confirmed necrotizing fasciitis caused by Group A Streptococcus in Yugoslavia was presented. Male patient, aged 28, in good health, suddenly developed symptoms and signs of severe infective syndrome and intensive pain in the axillary region. Parenteral antibiotic, substitutional and supportive therapy was conducted along with the radical surgical excision of the necrotizing tissue. The patient did not develop streptococcal toxic shock syndrome thanks to the early established diagnosis and timely applied aggressive treatment. He was released from the hospital as completely cured two months after the admission.  相似文献   
64.
Migraine is episodic, paroxysmal disorder where the headache represents the central symptom and is followed with different combinations of neurologic, gastrointestinal and vegetative changes. Not until the diagnostic procedures were developed, ischemic lesions were verified even in the patients with ordinary migraine. This is a report of a patient with migraine headache, followed twice by verified episodes of temporary ischemic attacks and verified focal ischemic lesion of cerebral parenchyma. The mitral valve prolapse was also detected. This all imposed the administration of combined prophylactic antimigrainous and anticoagulant therapy as an imperative because of the risk of the development of repeated ischemia of cerebral tissue. This association also confirmed an opinion that migraine is a wider disorder with the dominant dysfunction of limbic system.  相似文献   
65.
Myotonic dystrophy (MD) is a multisystem disease affecting numerous organs and systems. Cardiac involvement is frequent. Sudden death, due to fatal cardiac rhythm and conduction disturbances occurs in 30% of patients with MD. The aim of this study was to assess the possibilities and methods of early detection of myocardial and conduction system disturbances. ECG, 24-hr Holter monitoring, echocardiography and electrophysiologic studies of the conduction system (electrophysiologic study) were carried out in 45 patients. Analysis of late ventricular potentials was done in 36 patients. Genetic studies revealed multiplication of CTG triplets in all patients. Cardiological abnormalities were detected in 89% of our patients. Disturbances of intraventricular conduction with prolongation of HV interval were most frequent (72%). Electrophysiologic study was the most sensitive method for detecting heart involvement in MD (positive findings in 87% patients). Abnormal findings were also discovered by Holter monitoring (64%), ECG (58%), analysis of late ventricular potentials (55%) and by echocardiography in 46% patients. The results of this study indicate a high rate of cardiac involvement in MD.  相似文献   
66.
Activating mutants of ras are among the most frequently found genetic alterations in human cancers. Therefore, Ras appears to be an attractive target for therapeutic intervention using gene transfer. The protein kinase Raf-1 acts as a direct downstream effector of Ras and is involved in Ras-induced cellular transformation. Using the NIH3T3 fibroblast-derived tumor cell line PEJ, which expresses oncogenic Ha-rasG12V, we analyzed whether dominant negative mutants of Raf-1 can inhibit Ras-mediated transformation. Retroviral gene transfer was used to stably transduce PEJ cells with three different dominant negative mutants of Raf-1. This resulted in reversion of the transformed phenotype in vitro as evidenced by an increase in contact inhibition and reduced anchorage-independent growth. However, tumor formation in nude mice was significantly delayed only by one of these mutants. Therefore, dominant negative mutants of the oncoprotein Myc, which is known to synergize with Raf-1 in tumor formation, were transduced into PEJ cells expressing a dominant negative Raf mutant. This leads to killing of the cells. These results indicate that although interference with Ras-induced transformation using dominant negative mutants of Raf is feasible and effective in vitro using retroviral vectors, an additional block (e.g., that of Myc) is necessary to kill PEJ cells. These results also indicate that interference with Ras-dependent signaling is not sufficient for inhibition of tumor formation of PEJ cells in vivo.  相似文献   
67.
Neoplastic development is a multistep process that involves the stochastic accumulation of heritable genetic alterations in proto-oncogenes, DNA repair genes, and tumor suppressor genes. Loss of heterozygosity (LOH) analysis has been used successfully to identify the genetic determinants of neoplastic development, including tumor suppressor genes, in several species and organs but not in the rat liver. We report the results of a sensitive genome-wide LOH analysis of rat hepatocellular carcinomas (HCCs). Heterozygous rats (Wistar-Furth x Fisher 344) were subjected to an Initiation-Promotion-Progression (IPP) protocol of hepatocarcinogenesis. Two weeks after initiation (by partial hepatectomy, 10 mg/kg diethylnitrosamine), the rats were placed on a diet containing 0.05% phenobarbital (PB). After 24 wk of PB promotion, the rats received either 100 or 1 50 mg/kg ethylnitrosourea. Hepatocellular tumors were resected after a total of 76wk of PB promotion. LOH analysis was completed on 26 HCCs by using 60 microsatellite markers covering all 20 rat autosomes and chromosome X. While 85% of the HCCs had one or more allelic imbalances, the average HCC had 3.3 allelic imbalances (range 0-9). A conditional hypothesis-testing method called the Hot-Cold model was used to determine the location of statistically significant elevations in the frequency of allelic imbalances. Elevated allelic imbalances were observed on chromosomes 1q, 6, 8, 11, 15, 17, and 20p. Together, these allelic imbalances suggest that the retinoblastoma and insulin-like growth factor genes as well as the resistance to chemical carcinogenesis (rcc) locus may be involved in HCC development in the rat but that LOH of the p53 gene is not. The elevated rate of allelic imbalances on chromosomes 8,11, and 17 may indicate the location of undiscovered tumor suppressor genes important to neoplastic development in rat liver. Microdissection-based LOH analysis of HCC revealed that contamination of non-neoplastic and nonhepatocellular tissue was not masking LOH in the whole-tumor analysis. There were no statistically significant differences in the frequency of allelic imbalances between HCC of any differentiation state (histological grade). To the degree that it does not reflect differences in etiological factors, the absence of allelic imbalances in chromosomal regions containing the p53 and mamose-6-phosphate/insulin-like growth factor II receptor tumor suppressor genes and the generally low frequency of allelic imbalances in these tumors, suggests that LOH and allelic imbalances play a less significant role in the molecular pathogenesis of HCC in rats than humans.  相似文献   
68.
We have recently demonstrated that DNA coding for both subunits of the murine IL-12 heterodimer exhibits a strong antimetastatic effect against B16-melanoma in C57BL/6 mice and after intratumoral injection tumor regression. Here we show that the antimetastatic effect can be detected when the DNA is injected intramuscularly 30 days before tumor cell challenge. A long-term IL-12 expression was measured for up to 50 days in the serum with a peak at day 20 amounting to about 10 ng/mL in C57BL/6 mice. CpG oligodeoxynucleotides also induce IL-12 expression, however, only for a few hours. IL-12 DNA administration induces long-lasting systemic IFN -gamma production, whereas IL-4 and TNF-alpha levels remained undetectable. NK cell-depleted mice showed a strong but reduced expression of murine IL-12. Expression of DNA encoding human instead of murine IL-12 resulted in a significantly lower and transient expression, indicating that not plasmid-derived IL-12 production alone but the immune system of the host contributes to the long- lasting antimetastatic effect. It may be attributable to an autocrine feedback mechanism maintaining murine IL- 12 expression, whereby several cell populations including NK cells are involved.  相似文献   
69.
AIMS: The purpose of this study is the assessment of efficiency of distraction osteogenesis (DO) as a method of operative treatment of knee arthrosis with co-existent varus deformity. MATERIAL AND METHODS: Authors undertook an attempt of evaluation of results of tibial corticotomy in 21 patients (25 operated knee joints) treated in Orthopaedic Clinic of Wroclaw Medical University in years 1995-2001, with the use of circular, external Ilizarov's fixator. All the operated patients underwent corticotomy of proximal tibial metaphysis followed by slow axis correction and bone regenerate formation started at 7th postoperative day. In orthopaedic examination functional evaluation of knee joint with modified point scale according to Ranawat (HSS-score) there were taken into account. In rentgenometric examination the limbs axis in the frontal plane and joint space morphology according to Ahlback were evaluated. RESULTS: The results in our group of patients were very encouraging. Accordingly to Ranawat scale, in majority of patients assessed before the treatment as poor and fair moved to group assessed as fair and good and even excellent. We observed decelerated regenerate formation and remodeling probably caused by advanced age of patients in 6 cases. In 3 cases persistent lose of entire correction was observed. CONCLUSIONS: In author's opinion DO as a method of operative treatment of unicompartmental knee arthrosis could be advocated as alternative method to traditional tibial osteotomy considering its biological effect stimulating regeneration of all tissues including cartilage even in advanced unicompartmental arthrosis.  相似文献   
70.
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