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排序方式: 共有7414条查询结果,搜索用时 15 毫秒
31.
Steffen Dietzel Anna Jauch Dirk Kienle Guoquiong Qu Heidi Holtgreve-Grez Roland Eils Christian Munkel Michael Bittner Paul S. Meltzer Jeffrey M. Trent Thomas Cremer 《Chromosome research》1998,6(1):25-33
Fluorescence in situ hybridization (FISH) with microdissection probes from human chromosomes 3 and 6 was applied to visualize arm and subregional band domains in human amniotic fluid cell nuclei. Confocal laser scanning microscopy and quantitative three-dimensional image analysis showed a pronounced variability of p- and q-arm domain arrangements and shapes. Apparent intermingling of neighbouring arm domains was limited to the domain surface. Three-dimensional distance measurements with pter and qter probes supported a high variability of chromosome territory folding. 相似文献
32.
Flow Perfusion Culture of Marrow Stromal Cells Seeded on Porous Biphasic Calcium Phosphate Ceramics 总被引:2,自引:0,他引:2
Holtorf HL Sheffield TL Ambrose CG Jansen JA Mikos AG 《Annals of biomedical engineering》2005,33(9):1238-1248
Calcium phosphate ceramics have been widely used for filling bone defects to aid in the regeneration of new bone tissue. Addition of osteogenic cells to porous ceramic scaffolds may accelerate the bone repair process. This study demonstrates the feasibility of culturing marrow stromal cells (MSCs) on porous biphasic calcium phosphate ceramic scaffolds in a flow perfusion bioreactor. The flow of medium through the scaffold porosity benefits cell differentiation by enhancing nutrient transport to the scaffold interior and by providing mechanical stimulation to cells in the form of fluid shear. Primary rat MSCs were seeded onto porous ceramic (60% hydroxyapatite, 40% β-tricalcium phosphate) scaffolds, cultured for up to 16 days in static or flow perfusion conditions, and assessed for osteoblastic differentiation. Cells were distributed throughout the entire scaffold by 16 days of flow perfusion culture whereas they were located only along the scaffold perimeter in static culture. At all culture times, flow perfused constructs demonstrated greater osteoblastic differentiation than statically cultured constructs as evidenced by alkaline phosphatase activity, osteopontin secretion into the culture medium, and histological evaluation. These results demonstrate the feasibility and benefit of culturing cell/ceramic constructs in a flow perfusion bioreactor for bone tissue engineering applications. 相似文献
33.
David W. Barbara William D. Edwards Heidi M. Connolly Joseph A. Dearani 《Cardiovascular pathology》2008,17(3):166-171
BACKGROUND: Ebstein's anomaly has been described extensively in autopsy material. However, there have been no large surgical pathology series of this malformation. OBJECTIVE: To review clinical and surgical pathologic features of a large number of cases of Ebstein's anomaly from a single institution. METHODS: Review of medical histories, surgical reports, and surgical pathology reports at the Mayo Clinic (2000-2005). RESULTS: Among 104 patients, the mean age was 31 years (2 months-79 years), and 57% were female. Common ECG abnormalities included right bundle branch block (58%), first-degree heart block (31%), preexcitation (18%), and nonspecific intraventricular conduction delay/block (15%). Moreover, 74% had inter-atrial communication, 13% mitral valve prolapse, and 5% bicuspid aortic valve. Clinically, all had tricuspid regurgitation (severe in 74%), and 17% of anterior leaflets were fenestrated. No tricuspid valve was calcified. Surgically, tricuspid tissue was removed during replacement in 99% and repair in 1%. The anterior tricuspid leaflet was resected in 98%, and its length was 0.81-9.3 cm/m2 body surface area (mean, 3.3). Characteristically, leaflets were large and had irregular shapes and numerous short cordal or direct myocardial insertions. One tricuspid valve had two papillary fibroelastomas. None had clinical or pathologic evidence of active or healed endocarditis. CONCLUSIONS: Among patients with Ebstein's malformation, tricuspid valve tissue almost exclusively was removed during valve replacement and represented the anterior leaflet. Valve tissue was generally large, irregularly shaped, and associated with insertion of short cords or myocardial stumps. Interestingly, although appreciably deformed, Ebstein valves were not associated with infective endocarditis. 相似文献
34.
Werahera PN Miller GJ Torkko K Crawford ED Stewart JS Deantoni EP Miller HL Lucia MS 《Human pathology》2004,35(7):798-807
Advances in the detection of carcinoma of the prostate during the last 15 years have accounted for a sharp increase and then an abrupt decrease in the incidence of the disease. A more recent decline in its mortality rates has been variously interpreted as either the success of early detection and improved treatment or lead-time bias. The recently reported Prostate Cancer Prevention Trial had an overall detection rate that approached the 30%-40% prevalence rates reported in autopsy series in which men died of other causes. However, the prognostic information that can be obtained from prostate cancer found on biopsy is limited. Three-dimensional computer modeling is one technique that allows multiple studies on "immortal" prostates to test methods of biopsy sampling accuracy and to assist in the determination of the disease's severity. Computer modeling can assess detection rates and assesses tumor multifocality and heterogeneity. It can provide a more accurate representation of tumor volume, aiding in therapeutic decision making, and can assess sampling errors of various biopsy methods. It has been shown to be superior to wire-frame technique by immortalizing the original shape and dimensions of the surgically excised prostate gland. Moreover, our 3-dimensional computer modeling system improves upon other systems: It is more than a simple extension of the planimetric technique, and it is able to demarcate clearly the boundaries of Gleason grades just 1 grade apart. 相似文献
35.
Irene Boo Alexandra E Fischer Doug Johnson Ruth Chin Maxine Giourouki Mandvi Bharadwaj Scott Bowden Joseph Torresi Heidi Drummer 《Journal of clinical virology》2007,39(4):288-294
BACKGROUND: The role of neutralizing antibody (NAb) in determining response to antiviral therapy has not been established. OBJECTIVE: In this study we have analysed the kinetic's of the NAb response in patients with chronic hepatitis C who received antiviral therapy. STUDY DESIGN: Seventeen patients infected with genotype 1, 2a/c or 3a hepatitis C virus (HCV) were enrolled, eight with a sustained virological response (SVR), five non-responders and four relapsers. RESULTS: The mean NAb titre required to neutralize 50% of the E1E2-pp in patients who achieved an SVR (294+/-S.D. 51), in relapsers (246+/-S.D. 61.7) and non-responders (286+/-S.D. 80.95) did not differ significantly between the patient groups and did not alter during the course of treatment (P>0.01). Genetic variation present before antiviral therapy was analysed by single strand conformation polymorphism (SSCP) and failed to demonstrate a significant difference in the mean number of amplified E1E2 DNA fragments from the serum of patients who achieved an SVR (3.15+/-S.D. 1.53), relapsers (2.8+/-S.D. 1.32) or non-responders (3.69+/-S.D. 1.75). The baseline serum HCV viral loads were also not significantly different between patients who achieved an SVR (1.4 x 10(6) copies/ml; +/-S.D. 2.4 x 10(6)), relapsers (1.3 x 10(7) copies/ml; +/-S.D. 2.4 x 10(7)) and non-responders (1.5 x 10(6) copies/ml; +/-S.D. 1.1 x 10(6)). CONCLUSION: We have shown that neutralizing anti-HCVpp antibody is not associated with response to antiviral therapy. In addition, there was no correlation between baseline virological load, circulating viral quasi-species, NAb titres and final response to treatment. 相似文献
36.
37.
Lugli A Forster Y Haas P Nocito A Bucher C Bissig H Mirlacher M Storz M Mihatsch MJ Sauter G 《Human pathology》2003,34(10):994-1000
Calretinin is a calcium-binding protein expressed in different normal and neoplastic tissues. Early studies suggested that calretinin is a useful marker to differentiate adenocarcinomas from malignant mesotheliomas of the lung, but subsequent work has shown that calretinin can be expressed in several other tumor types. To systematically investigate the epidemiology of calretinin expression in normal and neoplastic tissues, we used tissue microarrays (TMAs) to analyze the immunohistochemically detectable expression of calretinin in 5233 tissue samples from 128 different tumor categories and 76 different normal tissue types. At least 1 case with weak expression could be found in 74 of 128 (58%) different tumor types and 46 entities (36%) had at least 1 tumor with strong positivity. In normal tissues, a particularly strong expression was found in Leydig cells of the testis, neurons of the brain, theca-lutein and theca interna cells of the ovary, and mesothelium. In tumors, strong calretinin expression was most frequently found in malignant mesotheliomas (6 of 7), Leydig cell tumors of the testis (5 of 5), adenomas of adrenal gland (5 of 9), and adenomatoid tumors (4 of 9). In summary, calretinin is frequently expressed in many different tumor types. Metastases of various different origins must be included in the differential diagnosis of calretinin-positive pleura tumors. 相似文献
38.
Laperriere A Ironson GH Antoni MH Pomm H Jones D Ishii M Lydston D Lawrence P Grossman A Brondolo E Cassells A Tobin JN Schneiderman N Weiss SM 《Journal of health psychology》2005,10(2):223-231
This prospective multisite Phase III clinical trial (Miami, New York, New Jersey) investigated the long-term (one year) effects of a 10-week group cognitive-behavioral stress management/expressive supportive therapy (CBSM+) intervention on disadvantaged minority women living with AIDS. The CBSM+ intervention consisted of 10-weekly group session of stress management, cognitive-behavioral skill training, relaxation techniques and expressive-supportive therapeutic strategies. The primary study outcome was self-reported depression scores as measured by the BDI. The CBSM+ Group intervention significantly decreased depression scores on the BDI for women following the intervention and maintained the decreased level at one-year follow-up. 相似文献
39.
An enzyme-linked immunosorbent assay (ELISA) for the major crustacean allergen, tropomyosin, in food
Heidi R. Fuller Philip R. Goodwin Glenn E. Morris 《Food and Agricultural Immunology》2006,17(1):43-52
Shellfish are a common cause of food reactions in hypersensitive individuals and are among the eight foods that account for over 90% of food allergies. At present, the only way to prevent these serious consequences of food allergies is to avoid the foods that trigger the reactions. A sandwich-ELISA kit has been developed for the detection of crustacean meat in food, based on the major heat-stable shellfish allergen, tropomyosin. Tropomyosin was purified from whole prawn (Penaeus latisulcatus) and used to immunize rabbits after confirming its identity by MALDI-TOF MS. A sandwich-ELISA based on the rabbit antibodies takes less than 2 h to perform, including the food extraction, and has a detection limit of 1 ppm crustacean (prawn, lobster), without detectable cross-reactivity with fish or mammalian meat. 相似文献
40.
Stöhr H Marquardt A Nanda I Schmid M Weber BH 《European journal of human genetics : EJHG》2002,10(4):281-284
The RFP-TM protein family was first described in Caenorhabditis elegans as hypothetical transmembrane proteins containing a conserved 350-400 amino acid domain including the invariant peptide motif RFP. The VMD2 gene underlying Best disease was shown to represent the first human member of the RFP-TM protein family. More than 97% of the disease-causing mutations are located in the N-terminal RFP-TM domain implying important functional properties. Here, we have identified three novel VMD2-related human genes (VMD2L1, VMD2L2 and VMD2L3) demonstrating a high degree of conservation in their respective RFP-TM domains. Each of the VMD2-like proteins has a unique C-terminus that lack similarity to other proteins or motifs. By FISH analysis, VMD2L1 was localised to chromosome 19p13.2-p13.12, VMD2L2 to 1p32.3-p33 and VMD2L3 to 12q14.2-q15. RT-PCR analyses revealed tissue-restricted expression of the three genes with both VMD2L1 and VMD2L2 abundantly transcribed in colon. VMD2L1 is present in the retinal pigment epithelium while VMD2L3 shows predominant expression in skeletal muscle. 相似文献