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11.
William G. Kohn Jonathan A. Ship Jane C. Atkinson Lauren L. Patton Philip C. Fox 《Journal of oral pathology & medicine》1992,21(2):70-74
Sequential salivary gland scintigraphy with 99mTc-technetium pertechnetate (Tc-99) is a safe, minimally invasive test for study of major salivary glands. However, its relationship to salivary function has not been investigated in detail. We have investigated the relationship between major salivary gland flow rates and Tc-99 scans and developed a new rating scale using scans of a control group with normal salivary function. Salivary flow rates and Tc-99 scans were obtained from healthy, non-medicated subjects (n = 33) and from xerostomic patients (n = 22). There were significant differences between the groups for salivary flow rates and Tc-99 ratings. Significant correlations were found between salivary flow rates and Tc-99 ratings in the control and xerostomic groups. The Tc-99 rating scale proved reliable in assessing salivary dysfunction, and showed a high inter-examiner correlation. These results demonstrate the usefulness of salivary gland scintigraphy in assessing major salivary gland flow rates and the utility of a new rating scale. 相似文献
12.
The high cycle fatigue strength of porous coated Ti-6A1-4V is approximately 75% less than the fatigue strength of uncoated Ti-6A1-4V. This study separates the effects of three parameters thought to be responsible for this reduction: interfacial geometry, microstructure, and surface alterations brought about by sintering. To achieve the goal of one parameter variations, hydrogen-alloying treatments, which refined the lamellar microstructure of beta-annealed and porous coated Ti-6A1-4V, were formulated. The fatigue strength of smooth-surfaced Ti-6A1-4V subjected to hydrogen-alloying treatments is 643-669 MPa, significantly greater than the fatigue strength of beta-annealed Ti-6A1-4V (497 MPa) and also greater than the fatigue strength of pre-annealed, equiaxed Ti-6A1-4V (590 MPa). The fatigue strength of porous coated Ti-6A1-4V, however, is independent of microstructure. This leads to the conclusion that the notch effect of the surface porosity does not allow the material to take advantage of the superior fatigue crack initiation resistance of a refined alpha-grain size. Thus, sinternecks acts as initiated microcracks and fatigue of porous coated Ti-6A1-4V is propagation controlled. 相似文献
13.
We report on a patient with trisomy 18 syndrome and tetrasomy 18p. The case indicates that the presence of an isochromosome i(18p) can mimic complete trisomy 18 syndrome. 相似文献
14.
P Merlob G Kohn A Litwin I Nissenkorn M B Katznelson S H Reisner 《American journal of medical genetics》1989,32(1):22-26
We describe a preterm female infant with multiple anomalies who has a duplication of a large part of 4q and partial deletion of chromosome 1q. Her karyotype was interpreted to be 46,XX,-1,+der(1),t(1;4) (q44;q23 or 24)mat. She is the first patient with an unbalanced translocation involving chromosomes 4 and 1. There is a substantial amount of concordance between the phenotypic features of this patient and those described in the context of partial deletion 1q. The extensive duplication of 4q has no dominant clinical effects in the present infant. These facts support the general concept of much more deleterious effects of deletions versus duplications in human species. 相似文献
15.
Detection of Mycoplasma pulmonis in arthritic joints of rats by indirect immunoperoxidase staining. 下载免费PDF全文
Neonatal and 8-week-old rats were inoculated with Mycoplasma pulmonis. A portion of the animals developed polyarthritis. Indirect immunoperoxidase staining was used to identify the localization of M. pulmonis within arthritic joints. M. pulmonis antigen was most often observed within cartilage in the neonatal group and in synovial tissue in the 8-week-old group. 相似文献
16.
Metastatic dissemination is the primary cause of death in ovarian cancer (OvCa) patients, and dissemination to pleural and peritoneal effusions is a common clinical event. Effusion samples were collected from 15 OvCa patients. Twenty-six samples were collected prospectively, two were archival, and eight were taken from patients with other malignancies. Twenty-nine samples were from malignant ascites, and seven specimens were pleural fluids. In addition, six ascites and two pleural fluids from noncancer patients were studied as effusion controls. Effusion supernatants were tested for migration-stimulation activity, using A2058 human melanoma cells as the index responder cell. Malignant samples induced a 400-1200% increase in migration. Sixty percent of the migration was inhibited by incubation of the malignant fluid with antifibronectin (FN) antibody, in contrast to 75% inhibition of control fluid-stimulated migration (P = 0.017). Gelatin zymography and Western blot analyses showed that latent and activated MMP-2 and MMP-9 collagenases, and tissue inhibitor of metalloproteinase-2 (TIMP-2) were present in all malignant fluids. Serial samples were taken from several patients, and a trend for correlation between MMPs and clinical behavior of the tumors was shown. Free TIMP-2 correlated with CA-125 levels in two patients for whom serial samples were available. The demonstration of promigratory and proinvasive activity in malignant effusions is consistent with their association with other metastatic disease in OvCa patients and their function as a haven for metastatic cells. 相似文献
17.
18.
Comparative study of laparoscopy vs. laparotomy for adnexal surgery: efficacy, safety, and cyst rupture 总被引:2,自引:0,他引:2
Operative laparoscopy is becoming routine in gynecologic surgery. This study was designed to compare the safety and efficacy of laparoscopy and laparotomy for ovarian cystectomy and adnexectomy. The medical records of 32 patients who underwent operative laparoscopy for adnexal masses (group L) were reviewed and compared with those of 32 patients who underwent surgical laparotomy (group S) for similar indications. All patients sustained either an ovarian cystectomy or adnexectomy. The group were matched for age, weight, and history of previous laparotomy. Median operating time for group L was 90 min and for group S was 85 min. Blood loss was significantly less in group L (33.4 +/- 22 mL) than in group S (84.6 +/- 22.2 mL), p < 0.0001. There were two intraoperative complications in group L and one in group S. Significantly less patients in group L had postoperative fevers (16%) as compared with those in group S (69%), p < 0.0001. There was a higher incidence of cyst rupture when cystectomy was performed in patients from group L (7 of 21) as compared with patients from group S (2 of 17). No such difference in cyst rupture was noted when an adnexectomy was affected in group L (1 of 11) and group S (1 of 15). Patients in group L remained in the hospital a shorter time period, 1.5 +/- 0.8 days, than patients in group S, 4.7 +/- 0.9 days, p < 0.0001. Patients in group L required a shorter postoperative recovery time before resuming normal activities, 9.1 +/- 6.6 days, than patients in group L, 27.5 +/- 9.2 days, p < 0.0001. Similarly, patients in group L required less time to become pain free, 10.1 +/- 7.4 days, than patients in group L, 17.7 +/- 6.1 days, p < 0.0005. This study demonstrates a statistically significant decrease in postoperative morbidity and faster recovery in patients undergoing laparoscopy for adnexal surgery as compared with patients undergoing laparotomy for the same procedure. When cystectomy is performed via the laparoscope, there is a higher incidence of cyst rupture than with laparotomy. 相似文献
19.
Screening methods for thyroid hormone disruptors 总被引:15,自引:0,他引:15
DeVito M Biegel L Brouwer A Brown S Brucker-Davis F Cheek AO Christensen R Colborn T Cooke P Crissman J Crofton K Doerge D Gray E Hauser P Hurley P Kohn M Lazar J McMaster S McClain M McConnell E Meier C Miller R Tietge J Tyl R 《Environmental health perspectives》1999,107(5):407-415
The U.S. Congress has passed legislation requiring the EPA to implement screening tests for identifying endocrine-disrupting chemicals. A series of workshops was sponsored by the EPA, the Chemical Manufacturers Association, and the World Wildlife Fund; one workshop focused on screens for chemicals that alter thyroid hormone function and homeostasis. Participants at this meeting identified and examined methods to detect alterations in thyroid hormone synthesis, transport, and catabolism. In addition, some methods to detect chemicals that bind to the thyroid hormone receptors acting as either agonists or antagonists were also identified. Screening methods used in mammals as well as other vertebrate classes were examined. There was a general consensus that all known chemicals which interfere with thyroid hormone function and homeostasis act by either inhibiting synthesis, altering serum transport proteins, or by increasing catabolism of thyroid hormones. There are no direct data to support the assertion that certain environmental chemicals bind and activate the thyroid hormone receptors; further research is indicated. In light of this, screening methods should reflect known mechanisms of action. Most methods examined, albeit useful for mechanistic studies, were thought to be too specific and therefore would not be applicable for broad-based screening. Determination of serum thyroid hormone concentrations following chemical exposure in rodents was thought to be a reasonable initial screen. Concurrent histologic evaluation of the thyroid would strengthen this screen. Similar methods in teleosts may be useful as screens, but would require indicators of tissue production of thyroid hormones. The use of tadpole metamorphosis as a screen may also be useful; however, this method requires validation and standardization prior to use as a broad-based screen. 相似文献
20.
Evidence for the genetic role of human leukocyte antigens in low frequency DRB1*1501 multiple sclerosis patients in Israel 总被引:2,自引:0,他引:2
Karni A Kohn Y Safirman C Abramsky O Barcellos L Oksenberg JR Kahana E Karussis D Chapman J Brautbar C 《Multiple sclerosis (Houndmills, Basingstoke, England)》1999,5(6):410-415
A strong association exists between multiple sclerosis (MS) and the DRB1*1501 haplotype, in most populations. Linkage of Multiple Sclerosis (MS) with the MHC or HLA region on chromosome 6p21 has previously been observed in DRB1*1501 positive MS families. A group of 13 Israeli multiplex MS families with a very low frequency of DRB1*1501 haplotype were examined in this study. Association and a linkage test were performed in order to identify a non-DRB1*1501 effect of HLA on susceptibility for MS. MS multiplex families and healthy controls were molecularly typed for six highly polymorphic markers located within the MHC region: DRB1, DQA1 and DQB1, BAT-2, MIB and D6S248. Data analyses included: (a) an association study comparing the patient group with both healthy relative, and healthy control groups (b) a transmission test for linkage disequilibrium (TDT) of the MS-associated alleles in the multiplex families, and (c) multipoint non-parametric linkage (NPL) and parametric LOD score analyses using the GENEHUNTER program. The DRB1*1303 allele was significantly more frequent among the MS patients. There was a trend towards transmission disequilibrium of DRB1*1303, but was not statistically significant. Allele sharing and LOD score analyses revealed no evidence for linkage. The high frequency of DRB1*1303 observed in our family patients provides evidence to support the association with this allele that previously described in sporadic non-Ashkenazi MS patients. Thus, DRB1*1303 may serve as genetic risk factor for MS. Our study exemplifies the genetic heterogeneity in MS as there is a genetic effect of HLA on MS susceptibility in our low frequency DRB1*1501 patients. 相似文献