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991.
Primary lung non-Hodgkin's lymphoma is a rare neoplasm mostly represented by low-grade B-cell lymphomas of mucosa-associated lymphoid tissue. Their diagnostic criteria are now well defined on surgical specimens, but pathologists may experience difficulties in distinguishing them on exiguous biopsies from benign lymphoid hyperplasia and other lymphomas. Therefore, we examined a series of 26 lung lymphoid lesions to further define the pathologic features of either lymphoma or lymphoid hyperplasia on small specimens. We observed 16 primary lung non-Hodgkin's lymphomas with a large predominance of low-grade mucosa-associated lymphoid tissue-type lymphomas (87.5%, n = 14). There were no autoimmune disorders, but three patients had a concomitant infectious disease (hepatitis C virus and Helicobacter pylori gastritis). One patient presented with a synchronous pulmonary adenocarcinoma. As well as the classical mucosa-associated lymphoid tissue cellular infiltrate, immunohistochemical characterization of the 14 mucosa-associated lymphoid tissue-type lymphomas revealed the CD20+/CD43+ centrocyte-like cell phenotype in 10 cases (71.5%). Although the lymphoepithelial lesions observed in all lymphomatous cases have been reported in lung lymphoid hyperplasia, the determination of B-cell CD20+/CD43+ phenotype of the intraepithelial lymphocytes highly increased the specificity of lymphoepithelial lesions. A monoclonal immunoglobulin heavy chain gene rearrangement was present in 71.4% of the mucosa-associated lymphoid tissue-type lymphoma specimens. Investigation of H. pylori by polymerase chain reaction detection was negative, even for the two cases associated with H. pylori gastritis.  相似文献   
992.
Total laparoscopic aortobifemoral bypass.   总被引:1,自引:0,他引:1  
AIM: To assess the feasibility of aortobifemoral bypass by a laparoscopic approach. MATERIAL AND METHODS: During November 2002 through July 2003 a total of 21 patients with aorto-iliac occlusive disease underwent total laparoscopic aortobifemoral bypass surgery. RESULTS: The median operative time was 240 (range 150-420) min with a median aortic cross-clamp time of 60 (30-120) min. Operating time was reduced with experience. The median blood loss was 500 (100-2500) ml. One conversion to open surgery for acute dilation of the small bowel was necessary. Post-operative complications occurred in five patients (coagulation problems, disseminated intravascular coagulation secondary to thrombosis of the left limb, cerebro-vascular accident, dyspnoea, lymph leak) and there was no peri-operative death. Median hospital stay was 7 (5-30) days. CONCLUSION: Aorto-bifemoral bypass using a total laparoscopic approach can be performed safely. As all new techniques, a learning curve is observed. This new technique should be evaluated in a larger randomised trial to assess its clinical value in comparison to conventional surgery.  相似文献   
993.
Hereditary factor VII (FVII) deficiency is a rare bleeding disorder. Dysfunctional FVII variants characterized by normal or reduced levels of FVII antigen and discordantly low FVII activity have been described. In this study, seven unrelated Tunisian patients with FVII deficiency were examined. Molecular analysis revealed that three probands harbored a novel Ser339Phe mutation, one proband was inferred to have a novel splice site mutation in intron 2, c.226-2 A>G and three probands had two previously described mutations, Arg304Gln and Cys310Phe. Expression of Ser339Phe in baby hamster kidney cells yielded secretion of FVII antigen at a concentration of 225+/-50 ng/ml, compared with 181+/-47 ng/ml in cells transfected with wild-type FVII but with no demonstrable FVII activity. FVII Ser339Phe bound to tissue factor similarly to the binding of commercial recombinant activated FVII or recombinant wild-type FVII and was normally activated by activated factor X. The major defect of FVII Ser339Phe was its inability to activate factor X in the presence of tissue factor. Modeling predicted that the substitution of Ser339 by Phe abrogated substrate docking.  相似文献   
994.
In a controlled polysomnographic (PSG) study that we recently performed in our laboratory, we noticed that some patients with a chief complaint of sleep bruxism reported concomitant non-myofascial pain in their masticatory muscles. To study the influence of such pain on the pattern of bruxism motor activity, we re-assessed the 2nd out of 2 consecutive PSG and masseter electromyographic (EMG) recordings of 7 bruxers without pain and 6 bruxers with concomitant jaw muscle pain. Among others, the selection of these patients was based on reports of current jaw muscle pain intensity, using 100-mm visual analogue scales. In our sample of bruxism patients with pain, levels of pain intensity did not differ significantly between bedtime and awakening in the morning. Although there were no significant differences between both subgroups of bruxers in the number of bruxism bursts per episode and the root-mean-squared EMG level per bruxism burst, bruxers with pain had 40% less bruxism episodes per hour of sleep. This suggests that non-myofascial jaw muscle pain decreases the number of initiations of bruxism episodes, but leaves their contents unaffected.  相似文献   
995.
The influence of lipid vehicles on the intestinal absorption of Ciclosporin was studied in vivo. The model takes into account the effect of the intestinal lipid digestion on the absorption after intraduodenal administration of [3H]Ciclosporin in olive oil or middle-chain triglyceride (MCT) to the bile duct-cannulated rat. Digested vehicles significantly promoted the absorption compared to nondigested vehicles. In the nondigested state, olive oil was a significantly better vehicle than MCT, whereas the difference between both lipids was only a trend in the digested state. Further studies with variants of this in vivo model should determine the influence of abnormalities of fat digestion and absorption on the pharmacokinetics and pharmacodynamics of a drug with a low therapeutical index.  相似文献   
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997.
Pediatric residents, nurses, and other hospital staff membersoften receive very limited training in adolescent psychologyduring their schooling. Often the training they do receive ispsycho-analytically oriented and stresses that adolescence isa period of tumultous development in which symptomatic behavioris quite common and psychiatric disturbances are transient.This study surveyed the beliefs of pediatric residents (N =13), nurses (N = 20), and adjunct personnel (N = 12) about adolescentturmoil and the transitory nature of symptoms displayed duringadolescence. The survey questionnaire consisted of 9 true-falseitems concerning the frequency and severity of parent-adolescentconflicts, the frequency of various symptoms, and the adolescent'slikelihood of "growing out of" such problems by adulthood. Theresults indicated a tendency among respondents to consider neuroticand antisocial behaviors to be more common than some recentstudies suggest they are, and falsely to believe adolescents"grow out of" their psychiatric problems. Implications of thesefindings are discussed.  相似文献   
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