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161.
Three-dimensional (3-D) intravascular ultrasound (IVUS) allows for the visualization of entire coronary segments, provides more detailed insights into the geometry of atherosclerotic plaques and facilitates serial studies. Automated quantitative 3-D IVUS methods reduce the analysis time and the subjectivity of boundary tracing, and permit complex IVUS studies. The 3-D IVUS approach is not restricted to research applications, but may be used as a valuable clinical tool. Evaluation of the coronary segment of interest before catheter-based coronary interventions provides information which may facilitate the selection of interventional devices. Moreover, 3-D IVUS allows for a careful assessment of the procedural results and potential post-procedural complications. ECG-gated image acquisition, automated contour detection, and approaches using data of both 3-D IVUS and biplane angiography represent the recent progress in this field. Three-dimensional IVUS will surely gain further importance and become a routine technique, if the interest and research effort is sustained.  相似文献   
162.
BACKGROUND: There is increasing use of highly sensitive testing with polymerase chain reaction (PCR) to study white cell microchimerism after transfusion and transplantation. This study investigated possible artifactual sources of allogeneic sample contamination before PCR testing. STUDY DESIGN AND METHODS: Quantitative Y-chromosome PCR was used to study microchimerism among transfused patients with sickle cell disease (SCD) and thalassemia by using residual specimens from the clinical laboratory. High levels of circulating male white cells among transfused patients with SCD but not thalassemia led to concern over the artifactual origin of male cells. To investigate, paired specimens were collected from 26 female SCD patients: one specimen underwent processing only for PCR, while the other underwent testing in the clinical laboratory before PCR as a process control. All laboratory instruments were also assessed for their ability to impart male allogeneic cells to aliquots of female blood. RESULTS: Thirty-three (31%) of 107 SCD samples, but 0 of 20 thalassemia samples, gave a high-level PCR signal. One of 26 paired samples that was not exposed to clinical laboratory equipment had low-level PCR positivity while 10 of the 26 became strongly positive after testing on a blood cell analyzer and a reticulocyte analyzer. Sixteen of 32 female samples became positive after reticulocyte analysis, while none became positive after blood cell analysis. Samples from thalassemia patients tested PCR-negative because reticulocyte counts had not been performed. CONCLUSION: Allogeneic cell contamination is common with clinical laboratory equipment. These samples may not be suitable for microchimerism studies. In addition to method controls, process controls should be employed where appropriate.  相似文献   
163.
AIM: To develop a brief, multi-dimensional instrument for assessing treatment outcome for people with drug and/or alcohol problems. The Maudsley Addiction Profile (MAP) is the first instrument to be developed in the United Kingdom for this purpose. DESIGN: Field testing with quota-recruitment of problem drug users and problem alcohol users in treatment with researcher and clinician-administered test-retest interviews. SETTING: Two community and two inpatient services at the Bethlem Royal and Maudsley Hospital, London. PARTICIPANTS: Subjects (160 drug users and 80 alcohol users) interviewed by eight interviews (four researchers and four clinicians), each of whom interviewed 30 subjects on two occasions. MEASURES: Sixty items across substance use, health risk, physical/psychological health and personal/social functioning domains. FINDINGS: Average completion time of the MAP was 12 minutes. The questionnaire was acceptable to a majority of subjects and performed well with both researcher and clinician interviewers. Internal reliability and feasible concurrent validity assessments of the scales and items were highly satisfactory. Test-retest reliability was good, average intraclass correlation coefficients across eight substances were 0.94 and 0.81 across health risk, health problems, relationship conflict, employment and crime measures. CONCLUSIONS: The MAP can serve as a core research instrument with additional outcome measures added as required. The collection of a set of reliable quantitative measures of problems among drug and alcohol users by research or treatment personnel for outcome evaluation purposes need not be time-consuming.  相似文献   
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166.
In immunocytes from the mollusc Mytilus galloprovincialis, the major pathway followed by platelet-derived growth factor (PDGF)-AB and transforming growth factor (TGF)-beta1 in provoking the release of norepinephrine, epinephrine and dopamine into cell-free hemolymph (serum) is mediated by a corticotropin-releasing hormone-adrenocorticotropin hormone (CRH-ACTH) biogenic amine axis. This axis not only annulled the inhibiting properties of PDGF-AB, it even reversed the latter's effect, while the inducing effect of TGF-beta1 was amplified. These findings show that non-classical immune-neuroendocrine molecules, such as PDGF-AB and TGF-beta1, are involved in building stress response, using the same conserved mechanisms present from invertebrates to vertebrates.  相似文献   
167.
One-day-old specific-pathogen-free White Leghorn chicks were inoculated orally with Salmonella enteritidis phage type 4 to study adhesion and invasion of the ceca by immunohistochemistry. Positive staining bacilli were associated with the epithelial surface and were present in the lumen of the cecal crypts. They were observed in the interstitial tissue and in the cytoplasm of macrophage-like cells in the lamina propria. A granulomatous nodule containing positive staining bacilli was present in the submucosa of the cecum of one bird at 14 d after inoculation.  相似文献   
168.
BACKGROUND: Cardiac memory (CM) refers to T-wave changes induced by ventricular pacing or arrhythmia that accumulate in magnitude and duration with repeated episodes of abnormal activation. We report herein the kinetics of long-term CM and its association with the ventricular action potential. METHODS AND RESULTS: Dogs were paced from the ventricles at rates of 110 to 120 bpm for approximately 3 weeks. CM characterized by gradual sinus rhythm T vector rotation toward the paced QRS vector evolved in all dogs regardless of pacing site (left ventricular [LV] anterior apex or base, posterior LV, or right ventricular free wall). Cardiac hemodynamics and myocardial flow (microsphere studies) were unaltered by the pacing. Recovery time for the memory T wave to return to control increased with duration of the previous pacing. The protein synthesis inhibitor cycloheximide markedly (P<.05) and reproducibly attenuated evolution of CM. When pacing was performed from the atrium, CM did not occur. Standard microelectrode techniques were used to study action potential from the LV free wall of control and CM dogs. CM was associated with increased action potential duration in epicardial and endocardial but not midmyocardial cells, significantly altering the transmyocardial gradient for repolarization. CONCLUSIONS: CM is a dynamic process for which the final T vector is predicted by the paced QRS vector and which is associated with significant changes in epicardial and endocardial but not midmyocardial cell action potential duration, such that the transmural gradient of repolarization is altered. It is unaccompanied by evidence of altered hemodynamics or flow, requires a change in pathway of activation, and appears to require new protein synthesis.  相似文献   
169.
Amphiregulin (Ar) is an EGF receptor ligand that functions to modulate the growth of both normal and malignant epithelial cells. We asked whether mouse preimplantation embryos express Ar, and if so, what the function of Ar is during preimplantation development. We used RT-PCR to show expression of Ar mRNA in mouse blastocysts, and using a polyclonal anti-Ar antibody and indirect immunofluorescence, we detected the presence of Ar protein in morula- and blastocyst-stage embryos. Ar protein was present in both the cytoplasm and nucleus in both morulae- and blastocyst-stage embryos, which is similar to Ar distribution in other cell types. Embryos cultured in Ar developed into blastocysts more quickly and also exhibited increased cell numbers compared to control embryos. In addition, 4-cell stage embryos cultured in an antisense Ar phosphorothioate-modified oligodeoxynucleotide (S-oligo) for 48 hr exhibited slower rates of blastocyst formation and reduced embryo cell numbers compared to embryos exposed to a random control S-oligo. TGF-alpha significantly improved blastocyst formation, but not cell numbers, for embryos cultured in the antisense Ar S-oligo. From these observations, we propose that Ar may function as an autocrine growth factor for mouse preimplantation embryos by promoting blastocyst formation and embryo cell number. We also propose that blastocyst formation is stimulated by Ar and TGF-alpha, while Ar appears to exert a greater stimulatory effect on cell proliferation than does TGF-alpha in these embryos.  相似文献   
170.
In this paper the effect of Ge substitution on the lattice parameter of Br sodalite has been studied. The sodalite was grown as a powder by the hydrothermal method. Lattice parameter measurements show a linear increase in ao with increasing amounts of Ge. The compositions of the powders were determined by the electron microprobe and spot checked by wet chemical analysis.  相似文献   
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