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Spontaneously elevated nociceptive threshold levels were markedly diminished after Naloxone injections in 4 patients with congenital insensitivity to pain. This finding suggested the hypothesis of a relation between congenital insensitivity to pain and permanent hyperfunction of an endomorphinic system. Radio-immunoassay of CSF beta-endorphin was performed in all 4 cases. The normal or only slightly elevated levels cannot explain electrophysiologic findings, but as a function of the multiplicity of endogenous opioid systems, hyperactivity of another endomorphinic system cannot be excluded. Other hypotheses may also be proposed.  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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Chronic myelomonocytic leukemia represents a distinct myelodysplastic syndrome in which an excess of monocytes is observed both in the blood and bone marrow of the patients. Whereas diagnosis is relatively easy, therapeutic design and efficacy is difficult and no treatment has to date provided complete or significant partial response. In vitro data suggest that the growth and differentiation of myelomonocytic progenitors may be altered inasmuch as monocytic or granulo-macrophagic colonies show spontaneous growth. Different entities may be observed: the childhood form, Juvenile Chronic Myelomonocytic Leukemia (JCML) shows in vitro a typical pattern with constitutive growth of only macrophagic colonies and hypersensitivity to GM-CSF; in the adult form at least two patterns may be observed one close to the JCML form and one more heterogeneous with absence of GM-CSF sensitivity and spontaneous growth of both CFU-GM and CFU-M colonies. Chemotherapy reduces all myeloid colonies in vitro whereas retinoic acid has a selective effect on monocytic colonies with a concomitant increase of CFU-G colonies forwarding an explanation for the correction of pancytopenia observed in some patients. Recent analysis of altered molecular pathways in this disease suggest a common disruption of intracelleular signalling pathways namely the Ras pathway and targetting for drugs with may selectively control or inhibit a constitutive activation may forward novel therapeutic perspectives.  相似文献   
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Background: Open exploration and endoscopic sphincterotomy (ES) remain the preferred treatment of common bile duct stones (CBDS). The recent spread of laparoscopy has worsened the dilemna of choosing between surgical and endoscopic treatment of CBDS. The aim of this study was to critically evaluate the results of our preliminary experience with laparoscopic common bile duct exploration (CBDE) for CBDS. Methods: Ninety-two consecutive patients were prospectively submitted to laparoscopic CBDE. Surgical strategy included an initial transcystic approach or laparoscopic choledochotomy. Failure of stone clearance was managed by conversion to open CBDE or by postoperative ES. Electrohydraulic lithotripsy and papillary balloon dilatation were selectively used. Stone clearance was assessed by choledochoscopy and control cholangiography. Results: The overall laparoscopic stone clearance in this series was 84% (transcystic route 63% and choledochotomy 93%). Conversion to laparotomy was mandatory in 12% of the patients because of incomplete stone clearance and in 5% because of intraoperative complications. Postoperative ES was required in 4% of the patients, giving an overall surgical success rate of 96%. When indicated (small and limited number of stones located below the cysticocholedochal junction, with a dilated and patent cystic duct) the transcystic route had the lower success rate, the higher complication rate, and the shorter operative time and postoperative hospital stay. When indicated (accessible and dilated common bile duct over 7 mm), laparoscopic choledochotomy had the higher success rate, the lower complication rate, the longer operative time, and the longer postoperative hospital stay, which is related to associated external biliary drainage. The hospital mortality included two high-risk patients (2%) and the complications rate was 15%. Conclusions: Laparoscopic CBDE is safe in selected patients. A stratified intraoperative surgical strategy is mandatory in deciding between a transcystic route and choledochotomy with specific indications for each approach. When feasible, laparoscopic choledochotomy is more efficient and safe than the transcystic route, but it is associated with a longer postoperative hospital stay, which is due to external biliary drainage. Received: 7 May 1996/Accepted: 19 November 1996  相似文献   
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