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991.
OBJECTIVE: Uterine abnormalities, such as leiomyomas, endometrial polyps, and adenomyosis, are often clinically associated with irregular uterine bleeding. These abnormalities can have similar B-mode characteristics but require different treatment. The objective of this study was to develop diagnostic techniques based on ultrasound strain imaging that would allow in vivo visualization and characterization of endometrial and myometrial uterine abnormalities, enabling physicians to improve diagnosis and treatment. METHODS: Ultrasound strain imaging was performed on 29 uteri removed via elective hysterectomy. An ultrasound system with a linear array transducer was used to obtain radio frequency echo data during manual freehand compressions of the tissue. Radio frequency data were post-processed with a 2-dimensional block-matching algorithm to generate strain images. RESULTS: In the uteri involved in this study, there were 19 leiomyomas, 1 case of adenomyosis, and 3 endometrial polyps observed on strain imaging. Leiomyomas appeared stiffer than the surrounding normal myometrium in strain images and were characterized by a slipping artifact at their boundary. Endometrial polyps appeared softer than the normal surrounding myometrium. The average strain contrast in small leiomyomas (<1.5 cm) compared to the myometrium was 1.75 +/- 1.14; the strain contrast was 2.50 +/- 1.15 in large leiomyomas and 0.40 +/- 0.05 in endometrial polyps. Leiomyoma strain contrast results were consistent with modulus contrast values from mechanical testing results. CONCLUSIONS: Ultrasound strain imaging can differentiate between endometrial polyps and leiomyomas. More data are necessary to validate these results and to ascertain whether other uterine abnormalities can also be differentiated.  相似文献   
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993.
Treatment of an infrahepatic caval anastomotic stenosis with percutaneous transluminal balloon angioplasty is described in a patient 5 weeks after liver transplantation. Pressure measurements confirmed the significance of the obstruction and the success of the dilatation procedure.  相似文献   
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997.
OBJECTIVE: Chondrocytes frequently de-differentiate in two-dimensional (2D) culture, especially in the presence of serum. To examine the role of lysyl oxidase (LOX) induced cross-linking in this phenomenon, the effect of the specific LOX inhibitor beta-aminopropionitrile (BAPN) was studied in 2D chondrocyte culture. DESIGN: Chick embryo sternal chondrocytes (both proliferative and hypertrophic, from caudal and cranial zones, respectively) were cultured in the presence and absence of BAPN. The production and activities of LOX and LOX-like (LOXL) were assessed by enzyme assay and the use of specific antibodies. Seventeen batches of serum of different origin were compared. Chondrocyte phenotype was assessed both morphologically and biochemically, the latter by quantitative analysis of production of radiolabeled cartilage collagens II, IX, X and XI, and the de-differentiation marker collagen I, for up to 4 weeks in culture. RESULTS: LOX and LOXL were identified, by Western blotting and immunofluorescence, and LO activity was measured in the medium, with both proliferative and hypertrophic chondrocytes. Inhibition of LO activity prevented or delayed chondrocyte de-differentiation, as characterized by changes in cell shape and synthesis of the five different collagen types, from the first days of culture for up to 4 weeks, depending on the origin of the serum added to the culture medium. CONCLUSION: LO activity may be involved in the control of chondrocyte phenotype, in addition to serum factors. Inhibition of LO activity by BAPN may be useful for the maintenance of the chondrocyte phenotype in 2D culture. Specific variations in the relative proportions of collagens II, IX and XI could be involved in the mechanism underlying these observations.  相似文献   
998.
Lang S  Rotter N  Lorenzen A  Ihrler S  Eckel R  Hölzel D  Rasp G  Wollenberg B  Sommer K 《HNO》2005,53(10):905-11; quiz 912-3
Salivary gland carcinomas comprise a rare group of malignant tumors which are difficult to diagnose and treat due to their histopathologic diversity, variable clinical course and anatomic location, particularly with respect to the facial nerve. The present paper summarizes important features of these tumors, including recent advances in their management, i.e., diagnosis, surgery of the primary tumor, neck dissection, radiation therapy, and updates risk factors, criteria of malignancy, and prognostic variables, taking into account the relevant literature. Additionally, the present paper highlights briefly the survival rates of patients suffering from salivary gland carcinomas. The present overview is divided into two parts: the first is focused on epidemiology, etiology, criteria of malignancy, prognostic factors, and tumor classification, while part II discusses the diagnosis and therapy of salivary gland carcinomas.  相似文献   
999.
Cystic fibrosis (CF) is a recessive disease caused by mutations of the CF transmembrane conductance regulator (CFTR) gene. The risk of idiopathic chronic pancreatitis (ICP) is increased in individuals who have CFTR genotypes containing a CF-causing mutation plus a second pathogenic allele. It is unknown whether the risk of ICP is increased in CF carriers who have one CF-causing mutation plus one normal allele. In this study, 52 sporadic cases of ICP were ascertained through the European Registry of Hereditary Pancreatitis and Familial Pancreatic Cancer. Individuals with pathogenic cationic trypsinogen mutations were excluded. DNA was comprehensively tested for CFTR mutations using a robotically enhanced, multiplexed, and highly redundant form of single-strand conformation polymorphism (SSCP) analysis followed by DNA sequencing. Fifteen subjects had a total of 18 pathogenic CFTR alleles. Eight subjects had common CF-causing mutations. This group included seven CF carriers in whom the second CFTR allele was normal (4.3 times the expected frequency, P=0.0002). Three subjects had compound heterozygotes genotypes containing two pathogenic alleles (31 times the expected frequency, P<0.0001). A variant allele of uncertain significance (p.R75Q) was detected in eight of the 52 ICP subjects and at a similar frequency (13/96) in random donors. ICP differs from other established CFTR-related conditions in that ICP risk is increased in CF carriers who have one documented normal CFTR allele. Having two CFTR mutations imparts a higher relative risk, while having only one mutation imparts a higher attributable risk.  相似文献   
1000.
Beckerling A  Braun W  Sommer M 《Digestion》2004,70(3):139-145
Often, the decision whether a patient can be considered as healthy or ill is very difficult and depends on measurements and the interpretation of the results. Therefore, it is necessary to build and establish devices that base on certain pre-considerations (who should assess the data, when and how should be measured). Additionally, these devices have to be valid, reliable and responsive. According to the literature we came to the conclusion that no uniform definition of what is 'healthy' exists. Referring to mathematical considerations we show an approach to solve this problem especially when the device is a scale. Based on the quality of the scale and of certain pre-considerations normal ranges can be established that will help to distinguish whether patients are 'healthy' or 'ill'. In this short review we discuss the problem of the establishment of a cut-off level on the basis of devices and we try to point out a solution to solve the arising problems.  相似文献   
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