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We report the results of 322 ultrasonically guided percutaneous fine-needle biopsies of focal intrahepatic lesions. The technique is original in several respects; it is an aspiration of both the lesion and normal-looking liver, and it includes both cytology and histology when the tiny cores are obtained. Cytology included Papanicolaou and Giemsa staining and other special staining when necessary. Sensitivity was 88.6% and specificity was 100% in the diagnosis of malignancy. Out of 141 metastases, 14 false negatives, 5 misclassifications, and 122 correct diagnoses were obtained. Out of 69 hepatomas the correct diagnosis of malignancy was made in 63 patients and of these the correct classification in 49. Complications occurred in six patients and marked hemorrhage in four. This technique is a simple, accurate, safe method for the diagnosis of focal intrahepatic lesions.  相似文献   
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BACKGROUND: Since 1997, a number of trials have shown promising results in treating generalized vitiligo with narrowband ultraviolet B (UVB) both in adults and children. However, there is little knowledge concerning the duration and permanency of the treatment-induced repigmentation. OBJECTIVE: Our main objective was to perform a follow-up trial of successfully treated patients receiving narrowband UVB for generalized vitiligo. METHODS: We have investigated to what degree the treatment-induced repigmentation remains stable for up to 2 years post-treatment. We performed an initial open trial including 31 patients with generalized vitiligo. They received narrowband UVB thrice weekly for up to 12 months. Patients experiencing > 75% repigmentation were defined responders and were included in the follow-up trial. Responders were followed every 6 months for up to 2 years after cessation of treatment. We observed the pigmentation status and registered any changes indicating loss of pigmentation and relapse. RESULTS: Eleven of the 31 treated patients were included in the follow-up trial. Six patients had relapse and five patients had stable response 24 months after cessation of treatment. Four out of six relapses were within 6 months post-treatment. CONCLUSION: In our study population of 31 patients with generalized vitiligo, five patients (16%) experienced > 75% stable repigmentation 2 years after cessation of a treatment programme of up to 1 years narrowband UVB therapy.  相似文献   
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We report two clinical pregnancies occurring after intracytoplasmic sperm injection (ICSI) using cryopreserved spermatozoa obtained from testicular biopsy, made in two different infertility situations in our clinic. The first patient showed a secretory azoospermia associated with elevated serum follicular stimulating hormone (FSH) level and spermiogenesis maturation arrest. The second patient was affected by azoospermia resulting from bilateral epididymal obstruction. Spermatozoa present in the wet preparation of testicular biopsy made on the day of scrotal exploration were cryopreserved within the testicular tissue for both men. Intracytoplasmic injections were performed at a later date, using spermatozoa prepared from frozen-thawed tissues. In each case, three embryos were obtained and transferred in utero. The transfers resulted in a twin pregnancy for the first case, and in a singleton pregnancy for the second. Living foetuses were seen in the ultrasound scan at the 7th week and both pregnancies are proceeding to date beyond 30 weeks without complications.   相似文献   
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The chemical stability of members of two groups of cytostatics, mitomycins and anthracyclines, has been studied in four different cell culture media enriched with serum. Stability was determined with the use of high performance liquid chromatography. In the group of mitomycins, the 7-aminomitosanes appeared to be relatively stable during a seven days incubation period at 37 degrees C when compared to the 7-methoxy congeners. The anthracycline derivatives, 4-demethoxy-daunorubicin, doxorubicin and its 4'-analogues showed half-lives of about 10-20 hours. Doxorubicinol and daunorubicin were found to be more stable. Anthracycline degradation products could be traced with the use of thin layer chromatography. All main degradation products originate from hydrolytic reactions. No enzymatic conversions could be observed. These observations may be of importance for the correct interpretation of the effects of mitomycins or anthracyclines on cells incubated in a cell culture medium.  相似文献   
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