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61.
M F Herrera I D Hay P S Wu J R Goellner J J Ryan J R Ebersold E J Bergstralh C S Grant 《World journal of surgery》1992,16(4):669-74; discussion 774-5
The latest World Health Organization International Classification defines papillary thyroid carcinoma by its "follicular cell differentiation...as well as characteristic nuclear changes". However the oxyphilic (Hürthle cell) papillary carcinoma have nuclei which generally resemble the nuclei seen in oxyphilic follicular carcinomas, and such oxyphilic papillary tumors may behave more aggressively than typical papillary cancers. To further characterize these rare tumors, we identified during a 32-year period 22 patients with oxyphilic papillary cancer and compared them with 1,084 patients with typical papillary cancers and 57 patients with oxyphilic follicular cancers treated by the Mayo surgical group during the same time period. Although typical papillary and oxyphilic papillary cancers were comparable with regards to patient age, tumor size and extent, TNM stage, and prognostic score (AGES), there were significant differences. Compared to typical papillary tumors, oxyphilic papillary cancers had fewer neck nodal metastases at primary diagnosis (5% vs 40%, p less than 0.0001), were more often DNA non-diploid (71% vs 21%, p less than 0.001), and after 10 postoperative years had higher rates of both tumor recurrence (28% vs 11%, p less than 0.0001) and cause-specific mortality (1.7% vs 4%, p less than 0.0005). In these four important respects the oxyphilic papillary cancers more resembled the oxyphilic follicular cancers. For oxyphilic follicular cancers, the frequency of initial neck nodal metastases was 7% (cf 5%); 83% of the oxyphilic follicular tumors were non-diploid (cf 71%), and at 10 years postoperatively the tumor recurrence and cause-specific mortality rates were 28% and 18%, insignificantly different from 28% and 17% seen with the oxyphilic papillary cancers.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
62.
Rheumatoid factors and complex formation. The role of light-chain framework sequences and glycosylation 总被引:2,自引:0,他引:2
New information regarding rheumatoid factors (RFs) indicates that the RFs synthesized in synovium and lymphoid tissues of patients with rheumatoid arthritis (RA) are different from monoclonal and nonspecific RFs associated with other inflammatory states. The characteristics of RF associated with RA are as follows. They are of all Ig isotypes (not just IgM), indicating T-cell participation in antibody maturation. They have higher avidity for human IgG than for rabbit IgG. They use the human germline heavy-chain variable region (VH) gene VHIII more frequently than other VH genes, and light chains from multiple families. (In contrast, monoclonal RFs use predominantly VH1 and very commonly the V kappa IIIb germline gene HUMkv325). RA IgG is somatically mutated. (In contrast, monoclonal RFs use unmutated germline Ig genes). This suggests they are matured by stimulation either with specific antigens or other activation signals such as cytokines. They are abnormally glycosylated. In general, during periods of disease activity in adult and juvenile RA, a galactose is missing from the Fc of the IgG molecule, leaving an empty "pocket" between the C gamma 2 domains of heavy chains. The IgG RFs self-associate. This may result at least in part when galactose on the F(ab')2 portion of one IgG molecule fills the empty pocket in the Fc of another Ig molecule. Self-association forms immune complexes capable of fixing complement and probably of causing joint damage and vasculitis. 相似文献
63.
The hypothesis of physician-induced demand is examined empirically in a model where variation in consumer information affects health-care utilization. A theoretical framework is posited under which demand-inducing physicians will provide more services, ceteris paribus, to their medically uninformed patients. Using data from the CHAS-NORC National Survey of Access to Medical uninformed patients. Using data from the CHAS-NORC National Survey of Access to Medical Care 1975-1976, physician office visit demand equations are estimated. The key finding is that medical professionals and their families are as likely, if not more likely, to visit physicians as other people, controlling for sociodemographic factors, price factors, access to care factors and perceived health status. 相似文献
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66.
Detection frequency of human herpesvirus 6 (HHV-6) and Epstein Barr virus (EBV) DNA in multiple sclerosis (MS) patients and controls was investigated. DNA of peripheral blood mononuclear leukocytes (PBL) was isolated and amplified by polymerase chain reaction techniques. EBV DNA was detected in all patients and controls. HHV-6 DNA was detected in 7% of MS patients and in 14% of controls. Results are compared with other investigations of HHV-6 DNA in PBL, serum, CSF and brain of patients with MS. Results of the present study and other investigations do not show an association between HHV-6 in PBL and MS. Multiple Sclerosis (2000) 6, 66 - 68 相似文献
67.
J.A. Stillman R.P. Morton K.D. Hay Z. Ahmad D. Goldsmith 《Clinical otolaryngology》2003,28(5):406-410
Electrogustometry is well established as a clinical tool for the estimation of taste detection thresholds. Nevertheless, the user is sometimes unaware of the impact of superficially minor procedural and psychophysical factors upon the reliability and comparability of threshold estimates. The inherent strengths and limitations of the procedure are outlined, and aspects of the control and specification of the stimulus that moderate threshold measures are discussed. In addition, threshold estimates from two individuals with severe unilateral taste loss are used to illustrate the level at which anodal dc current may elicit common, rather than taste, sensation. Where chorda tympani section is complete and historical (older than 7–14 days), very high stimulus levels, conservatively over 5 µA/mm2 (100 µA linear current with a 5‐mm diameter electrode), are required to activate trigeminal responses. 相似文献
68.
Parental awareness of risk factors for sudden infant death syndrome (SIDS) and infant care practices were compared in an area of relative deprivation and one of relative affluence in Cardiff. Awareness was high in both areas. More infants slept on the side in the deprived area (p < 0.02). One in three babies was exposed to cigarette smoking, significantly more in the deprived area (p < 0.001). Health professionals should discourage side sleeping and smoking, especially in areas of deprivation. 相似文献
69.
Msika S Iannelli A Marano A Zeitoun G Deroide G Kianmanesh R Flamant Y Hay JM 《Annales de chirurgie》2000,125(5):439-443
STUDY OBJECTIVE: Laparoscopic colectomies have been recently shown to be feasible and safe, with the use of stapling devices to fashion the anastomosis. The aim of this study was to evaluate the feasibility and safety of laparoscopic intra-abdominal hand-sewn anastomosis. PATIENTS AND METHODS: Seven patients (four males and three females, mean age 48 years) were included. There were two ileocolic resections for recurrence of Crohn's disease, two right colectomies (one for Crohn's disease and one for carcinoid tumor of the appendix), two left colectomies for diverticulitis and one segmental colectomy for sigmoid volvulus. There were: four side-to-side anastomoses, two side-to-end anastomoses and one end-to-end anastomosis. Anastomoses were fashioned with interrupted single layer sutures in four cases (two ileo-colic and two colorectal anastomoses) and with single layer running sutures in three cases (two ileo-colic and one colo-colic anastomoses). The specimens were retrieved by means of a plastic bag through a 3 to 5 cm long minilaparotomy in five cases and through the rectum in two cases. RESULTS: Mean additional time to perform hand-sewn intra-corporeal anastomosis was 90 +/- 15 min. There was no operative mortality and no intraoperative complications. Postoperative course was uneventful in six patients. Patients were started on an oral fluid diet on day 2 and discharged on day 5, except for one patient with Crohn's disease who had a severe anastomotic bleeding on postoperative day 2 and who required laparotomy for hemostasis through a service colotomy with a single suture. He was discharged on day 8. CONCLUSION: Intra-abdominal hand-sewn anastomoses are feasible and seem reliable. This represents a new step making laparoscopic procedures even closer to conventional techniques. This technique must be evaluated in larger series. 相似文献
70.
Methodological Studies on Genomic DNA Extraction and Purification from Plant Drug Materials 总被引:17,自引:0,他引:17
本文探讨了菊科9种植物和地胆草的4种对口商品药材基因组DNA提取与纯化的原理、方法通过对3种常用植物基因组DNA提取方法(CsCl梯度超速离心法、CTABCsCl梯度超速离心法和CTAB微量提取法)的条件摸索在DNA产率、纯度以及提取纯化过程中影响PCR扩增因子方面进行比较,认为CTAB微量提取法是植物类药材基因组DNA一种比较省时、有效、经济的提取方法 相似文献