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1.
Summary Early recognition of recurrence and work-up of clinically indeterminate lesions may be impaired after reconstruction with silicone implants due to superimposition of the implant or to scarring. This study was undertaken to evaluate the use of contrast-enhanced MRI in patients with silicone implant after breast cancer. Contrast-enhanded MRI was offered to 169 patients. Comparative two- to three-view mammography was also performed in 169 patients, as well as comparative sonography in 144 patients. Conventional imaging and clinical examination detected only 8/13 recurrences, whereas 12/13 were detected by MRI. One recurrence had been visible as a strongly enhancing 2-mm dot in a previous examination (2 years before), but was not called. It was therefore counted as false negative. In addition, multicentricity was detected by MRI alone in two of three cases. MRI correctly diagnosed scar tissue in all cases with indeterminate findings. However, due to false-positive calls caused by enhancing granulomas specificity could not be improved. Contrast-enhanded MRI allowed decisive additional information in our study group and improved the sensitivity significantly (concerning all diagnoses). Contrast-enhanded MRI is recommended in patients with diagnostic problems or high risk of recurrence after silicone implants.   相似文献   
2.
BACKGROUND: The recent amalgamation of data by users of the Perinatal Problem Identification Programme (PPIP) throughout South Africa has culminated in the publication of the Saving Babies report. OBJECTIVES: To determine the absolute rate of death from intrapartum-related birth asphyxia, and the contribution of intrapartum-related asphyxia to total perinatal mortality in South African hospitals, and to identify the primary obstetric causes and avoidable factors for these deaths. METHODS: The amalgamated PPIP data for the year 2000 were obtained from 27 state hospitals (6 metropolitan, 12 town and 9 rural) in South Africa. In PPIP-based audit, all perinatal deaths are assigned primary obstetric causes and avoidable factors, and these elements were obtained for all deaths resulting from intrapartum-related birth asphyxia. RESULTS: There were 123,508 births in the hospitals surveyed, with 4,142 perinatal deaths among infants > or = 1,000 g, giving a perinatal mortality rate of 33.5/1,000 births. The perinatal mortality rate from intrapartum-related birth asphyxia was 4.8/1,000 births. The most frequent avoidable factors were delay by mothers in seeking attention during labour (36.6%), signs of fetal distress interpreted incorrectly (24.9%), inadequate fetal monitoring (18.0%) and no response to poor progress in labour (7.0%). The perinatal mortality rates for metropolitan, town, and rural areas were 30.0, 39.4 and 30.9/1,000 births respectively. The contribution of intrapartum-related birth asphyxia to perinatal mortality in these areas was 10.8%, 16.7% and 26.4% respectively. CONCLUSION: The high rates of perinatal death from intrapartum-related birth asphyxia in South Africa are typical of those in underdeveloped countries, with the most serious deficiencies in rural areas. Most of these deaths are avoidable and the reduction of these rates presents an important challenge to providers of perinatal care in this country. Areas worthy of research and action include provision of mothers' waiting facilities in rural regions, improvements in fetal monitoring, partogram-based labour management, and the establishment of midwifery staffing norms for South African labour units.  相似文献   
3.
The expression of four cytochrome (cyt.) P-450 isoenzymes has been studied in preneoplastic and neoplastic lesions during the course of nitrosamine-induced hepatocarcinogenesis in the female Wistar rat. Following exposure to diethylnitrosamine (50 or 100 ppm in the drinking water) for 10 days, animals were taken sequentially, and the livers were analyzed for the evolution of adenosine triphosphatase deficient focal lesions. These lesions were subdivided into different phenotypes with regard to their cyt. P-450 isoenzyme expression using serial frozen sections. Our results demonstrate that about 40% of the adenosine triphosphatase-deficient lesions show concomitant alterations in their cyt. P-450 isoenzyme contents. Of these lesions, islets which are characterized by decreased levels of at least three cyt. P-450 isoenzymes show a dramatic increase in their volumetric fraction of liver tissue with progression of time. Although only very few lesions express this phenotype, the contribution to the volumetric fraction of islet tissue raises from about 2% at 10 weeks to about 60% at 35 weeks after cessation of diethylnitrosamine treatment. By contrast, lesions which express less than two alterations in cyt. P-450 isoenzyme levels develop relatively slowly. Similar results were obtained when animals were exposed continuously to diethylnitrosamine for a period of up to 8 weeks. Following treatment of islet-bearing animals with phenobarbital, an induction of cyt. P-450 isoenzymes and NADPH-cyt. P-450-reductase was observed within preneoplastic and neoplastic lesions. This induction was most pronounced in large, expansively growing nodules, a type of lesion which displayed decreased levels of these enzymes in livers of animals not treated with phenobarbital. The elevation of the cyt. P-450 isoenzymes disappeared within 2 to 3 weeks after cessation of inducer treatment. Our results indicate that a high proportion of rapidly growing lesions has assumed a constitutive deficiency in cyt. P-450 isoenzyme expression during nitrosamine-induced hepatocarcinogenesis. This deficiency, however, is not an irreversible quality, since individual cyt. P-450 isoenzymes can be markedly induced by treatment with an enzyme inducer like phenobarbital. Thus, the observed decrease in cyt. P-450 expression during development of malignancy does not result from alterations in the cyt. P-450 encoding structural genes but may rather be related to abnormalities in the function of regulatory systems of a higher order which may play a central role in the maintenance of cell homeostasis.  相似文献   
4.
OBJECTIVE: The aim of this study was to evaluate the benefit of image fusion of CT (computertomography) and bone SPECT (single photon emission computed tomography) in diagnosis of head and neck cancer. METHODS AND PATIENTS: Computer based image fusion has been applied in 39 patients with suspected cancer in the oromaxillofacial region following CT and SPECT without any further hazard for the patients. Afterwards image fusion was set in comparision to simultaneously evaluation of CT and SPECT and histological findings. RESULTS: In 5 out of 39 patients SPECT/CT image fusion obtained more precise anatomical findings in tumour expansion than simultaneously evaluation of CT and SPECT. CONCLUSION: For planning of surgical and radiation therapy of oral and maxillofacial cancer, image fusion of CT/SPECT provides efficient and plastical diagnostic imaging. Particularly in complex anatomical regions like maxilla or base of the skull image fusion could be an additional device, if simultaneous evaluation of CT and SPECT is not clear.  相似文献   
5.
Between January 1987 and December 1988 thoracoscopic pleurodesis has been used as a standard treatment for idiopathic spontaneous pneumothorax. Bullae were electrocoagulated, and visceral and parietal pleurae were cauterized. Chemical pleurodesis with 50% glucose-solution was added. 34 procedures were performed on 32 patients. The average hospital stay was 8 +/- 2 days. One patient suffered from postoperative Horner-syndrome. No other complications occurred. Patients were re-evaluated 11 +/- 8 months after the operation. Recurrence was found in four patients within 30 days. These patients underwent pleurectomy. Another patient had recurrence after two months. He was again and successfully treated by thoracoscopic pleurodesis. Our data show improvement of the results as compared with simple chemical pleurodesis.  相似文献   
6.
Duodenogastric reflux has often been discussed as a causative factor in the pathogenesis of gastric carcinoma. The author's clinical examinations of 135 patients with primary cancer of the stomach revealed slight increase in duodenogastric reflux. Yet, apart from these findings, no correlations were found to exist between reflux incidence and tumour localisation nor between histological tumour type and tumour size.  相似文献   
7.
Apoptosis, the programmed death of cells, plays a distinct role in the etiopathogenesis of Multiple sclerosis (MS), a common disease of the central nervous system with complex genetic background. Yet, it is not clear whether the impact of apoptosis is due to altered apoptotic behaviour caused by variations of apoptosis-related genes. Instead, apoptosis in MS may also represent a secondary response to cellular stress during acute inflammation in the central nervous system. Here, we screened 202 apoptosis-related genes for association by genotyping 202 microsatellite markers in initially 160 MS patients and 160 controls, both divided in 4 sets of pooled DNA samples, respectively. When applying Bonferroni correction, no significant differences in allele frequencies were detected between MS patients and controls. Nevertheless, we chose 7 markers for retyping in individual DNA samples, thereby eliminating 6 markers from the list of candidates. The remaining candidate, the ERBB3 gene microsatellite, was genotyped in additional 245 MS patients and controls. No association of the ERBB3 marker with the disease was detected in these additional cohorts. In consequence, we did not find further evidence for apoptosis-related genes as predisposition factors in MS.  相似文献   
8.
Langerhans cells (LC) take up Leishmania major and are critical for the induction of the parasite-specific T-cell response. Their functional activities are regulated by cytokines. We analyzed whether infection of LC with L. major modulates the expression of their cytokine receptors. The expression of the interleukin 4 (IL-4) receptor was increased on infected LC from susceptible mice but not on those from resistant mice. Moreover, IL-4 treatment strongly decreased the lipopolysaccharide-induced IL-12 response of infected LC from susceptible mice. This modulation of IL-4 receptor expression and IL-12 production by infection of LC with Leishmania may contribute to the development of Th2 cells and to susceptibility to infection.  相似文献   
9.
Summary Digital subtraction angiography (DSA) has strongly influenced angiographic procedures. Because it is less invasive it has increased the total number of angiographies in all places where it was introduced. The paper gives an introduction to the procedure explaining the roles of digital and subtraction in DSA. It is written from a technical point of view. The examples are taken from and with the DVI system.  相似文献   
10.
Zusammenfassung Seit Juli 1986 erfassen wir alle Patienten mit analen spitzen Kondylomen, prüfen den HIV-Status, sofern nicht bereits bekannt, and identifizieren das zugrunde liegende Human papilloma virus (HPV) mittels DNA-DNA-Hybridisierung (Southern-Blot). Von 70 erfaßten Patienten sind 39 seropositiv. Das Verhdltnis von Männern and Frauen beträgt 59 zu 11, bei seropositiven Patienten 35 zu 4 and bei seronegativen 24 zu 7. Das Durchschnittsalter liegt bei 28 respektive 31 Jahren. Der Anteil an Fixern and Homosexuellen liegt bei den Seropositiven signifikant höher. Nach der CDC-Klassifikation sind 17 Patienten im HIV-Stadium II, 11 im Stadium III and 10 im Stadium IV. Charakteristisch für die sero-positive Gruppe sind ausgedehnte Kondylomrasen auf der Rektalschleimhaut sowie rasant wachsende Restbefunde bei anfdnglich subtotaler Resektion zur Steno-seprophylaxe. Bei 65 Patienten wurde eine primdr radikale Resektion mit dem Elektrokauter vorgenommen. Ober-raschenderweise liegt die Rezidivquote bei Seronegativen höher, wobei das Rezidiv klein ist. Eine Hypothese dazu wird präsentiert. Postoperative Komplikationen traten nur in den HIV-Stadien III and IV auf. Wir empfehlen deshalb in diesen Stadien eine perioperative Antibiotika-prophylaxe. Die HPV-Identifikation ergab keine mit Malignität assoziierten Typen. Wir finden eine Häufung von HPV 11 bei seropositiven Patienten, deren Bedeutung uns nicht klar ist. Wir schlieen aus unseren Ergebnissen, daß, bei gegebener Operationsindikation, die primär radikale Abtragung der Kondylome mit dem Elektrokauter beim HIV-positiven Patienten notwendig ist and beim seronegativen ein sicheres Verfahren darstellt. In den HIV-Stadien III and IV ist eine Antibiotikaprophylaxe notwendig. Anale spitze Kondylome sind ein Hinweis auf eine mogliche HIV-Positivitdt.
Anal codylomata acuminata in HIV-positive patients
Summary Since July 1986 we started with following all patients with condylomata acuminata including HIV-testing and human papilloma virus (HPV) identification by DNA-DNA-hybridisation (southern blot). Seventy patients are included, 39 of them are seropositive. The ratio male to female is 59 to 11, in seropositives 35 to 4, in negatives 24 to 7. The average age is 28 and 31 years respectively. The number of homosexuals and junkies is significantly higher in seropositives. Seventeen patients are in HIV-stage II, 11 in stage III and 10 in stage IV according to CDC-classification. Characteristic for the seropositives was an extensive growth on the rectal mucosa and the very rapid growth of initially subtotally resected lesions in order to prevent stenosis. Sixty-five patients were treated by one stage radical operation with electrocauter. Surprisingly recurrency is more frequent in seronegatives, however, the lesion is much smaller in this group. A hypothesis to explain this observation is brought forward. Postoperative complications occurred only in HIV-stages III and IV We therefore recommend single shot antibiotic prophylaxis in these patients. The HPV-identification showed no malignancy associated HPV-types in both groups but a higher incidence of HPV 11 in higher HIV-stages which we cannot explain. We conclude from our series that, if operation is indicated, one stage radical electrocoagulation of condylomata acuminata is a necessary procedure in seropositive patients and a save one in negative patients but antibiotic prophylaxis should be given in stage III and IV. Anal condylomata acuminata are a hint for possible HIV-positivity.
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