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11.
The assessment of blood damage and of the activation of the coagulation, complement and/or inflammatory systems by cardiovascular and extracorporeal devices is difficult at best. Immunoassay methods are now available for the measurement of many of the proteins, enzymes and peptides involved in coagulation, thrombosis, complement and inflammation. We present a long-range project and plan to develop an array of remote, on-line, semicontinuous immunosensors for selected coagulation proteins, based on fluoroimmunoassay principles. The free/bound separation step is performed optically. Excitation of fluorescence is performed via an evanescent wave produced by total internal reflection and waveguide optics. Fluorescence emission is collected only in the near field. Means to deliver fluorescently-labelled reagent and to modify the antigen-antibody binding constant are presented and discussed. The results of non-specific binding, plasma-blood fluorescence, and blood compatibility are also discussed.  相似文献   
12.
BACKGROUND AND PURPOSE: Vancomycin-resistant enterococci (VRE) have emerged as important nosocomial pathogens. This study was conducted to clarify the clinical features and outcome of patients with vancomycin-resistant enterococcal bacteremia. METHODS: Patients with vancomycin-resistant enterococcal bacteremia treated at a medical center in northern Taiwan between November 1998 and July 2006 were reviewed. Clinical and bacteriological characteristics of Enterococcus faecium and Enterococcus faecalis were compared. RESULTS: Twelve patients (6 males and 6 females) were included for analyses. The mean age was 69.3 years (range, 40 to 86 years), and 8 cases (66.7%) were older than 65 years. All patients had underlying disease. Two patients received total hip replacement before development of VRE bacteremia. Twelve patients had prior exposure to broad-spectrum antimicrobial therapy. Ten patients had prior intensive care unit stay and prior mechanical ventilation before VRE bacteremia. All of the patients (n = 12) had an intravascular catheter in place. Bacteremia was caused by E. faecalis in 4 patients and by E. faecium in eight. The portals of entry included urinary tract (8.3%), skin, soft tissue and bone (41.7%) and unknown sources (50.0%). E. faecium showed a higher rate of resistance to ampicillin and teicoplanin than E. faecalis (87.5% vs 0.0%, p=0.01). The 60-day mortality rate was higher in patients with E. faecium bacteremia than E. faecalis bacteremia (62.5% vs 0.0%), although statistical significance was not obtained (p=0.08). CONCLUSIONS: VRE bacteremia may have an impact on the mortality and morbidity of hospitalized patients. Patients with bacteremia caused by vancomycin-resistant E. faecium had a grave prognosis, especially immunosuppressed patients. The prudent use of antibiotics and strict enforcement of infection control may prevent further emergence and spread of VRE.  相似文献   
13.
We have recently reported isolation of the gene responsible for X- linked Opitz G/BBB syndrome, a defect of midline development. MID1 is located on the distal short arm of the human X chromosome (Xp22. 3) and encodes a novel member of the B box family of zinc finger proteins. We have now cloned the murine homolog of MID1 and performed preliminary expression studies during development. Mid1 expression in undifferentiated cells in the central nervous, gastrointestinal and urogenital systems suggests that abnormal cell proliferation may underlie the defect in midline development characteristic of Opitz syndrome. We have also found that Mid1 is located within the mouse pseudoautosomal region (PAR) in Mus musculus , while it seems to be X- specific in Mus spretus. Therefore, Mid1 is likely to be a recent acquisition of the M. musculus PAR. Genetic and FISH analyses also demonstrated a high frequency of unequal crossovers in the murine PAR, creating spontaneous deletion/duplication events involving Mid1. These data provide evidence for the first time that genetic instability of the PAR may affect functionally important genes. In addition, we show that MID1 is the first example of a gene subject to X-inactivation in man while escaping it in mouse. These data contribute to a better understanding of the molecular content and evolution of the rodent PAR.   相似文献   
14.
The expression of mouseZfx, Rps4, Ube1x, andXist was evaluated in hamstermouse somatic cell hybrids containing either an active or an inactive mouse X chromosome using polymerase chain reaction of reverse transcribed RNA (RT-PCR). The results showed thatZfx, Rps4, andUbe1x are expressed exclusively from the active mouse X, whileXist is expressed exclusively from the inactive X. These findings confirm the pattern of X inactivation for these mouse genes reported previously based on expression in somatic tissues of F1 females from interspecific crosses. These results demonstrate the existence of differences between human and mouse X inactivation, as the corresponding human genes,ZFX, RPS4X, andUBE1 escape X inactivation.  相似文献   
15.
This study compared depressive symptomatology among Chinese psychiatric outpatients versus the general Chinese population, and across 3 cultural groups--Chinese, Chinese American, and Caucasian American students--by use of the Center for Epidemiological Studies-Depression Scale (CES-D; L. S. Radloff, 1977) and the Chinese Depression Scale (N. Lin, 1989), translated from the CES-D. Results indicate that Chinese patients (n = 112) endorsed a higher proportion of somatic symptoms than nonpatients (n = 112). The intercultural comparison found that Chinese students (n = 98) had the lowest levels of somatic depressive symptom endorsement compared to both U.S. groups (n = 198). These findings seem to suggest that the tendency toward somatic symptom reporting is not any greater among Chinese populations but may be a function of having a mental illness or of help seeking in China.  相似文献   
16.
Five cases of benign lymphoepithelial cysts (BLCs) of the parotid gland are reported, and the histologic, aspiration cytologic, and ultrastructural findings are described in detail. These uncommon parotid lesions contain epithelium-lined cystic spaces encased by abundant lymphoid tissue with germinal centers. The epithelium was "mucoepidermoid" in three of our cases and squamous in two. Familiarity with the morphologic features of BLCs should make it possible to distinguish them from similar-appearing cystic lesions, especially low-grade cystic mucoepidermoid carcinoma and cystic types of benign lymphoepithelial lesion (so-called Mikulicz's disease). These distinctions, however, are difficult on aspiration cytology specimens.  相似文献   
17.
The anatomy of the cardiac conduction system in normal and malformed hearts reconstructed from histological serial sections is reviewed. The sinus node and its arterial supply are located in the right superior cavoatrial junction except in hearts with left-sided juxtaposition of the atrial appendages, mirror-image, and isomeric arrangements of the atria. In the presence of normally positioned atrial and ventricular septal structures, the triangle of Koch is a useful guide to the location of the atrioventricular node and the penetrating bundle. In hearts with isolated ventricular septal defects, it is necessary to distinguish between a perimembranous defect and a muscular inlet defect. The conduction axis runs in the area of fibrous continuity at the posteroinferior edge of a perimembranous defect but in the anterosuperior rim of a muscular inlet defect. In most hearts with tetralogy of Fallot, the danger area is the region of aortic-mitral-tricuspid fibrous continuity where the axis penetrates. In hearts with atrioventricular septal defects, the lack of contiguity between atrial and ventricular septum results in a posterior displacement of the nodal triangle and coronary sinus and an elongation of the nonbranching bundle. Hearts with abnormally located atrioventricular nodes and conduction axes are mainly those with atrioventricular discordance, ambiguous atrioventricular connection in presence of left-hand pattern ventricular topology, hearts with univentricular atrioventricular connection to a morphologically left or indeterminate ventricle, and hearts with a straddling tricuspid valve. The location of the atrioventricular node is governed by the orientation of the ventricular septum and by the pattern of ventricular topology.
Resumen Se revisa la anatomía del sistema de conducción cardiaca en los corazones normales y con malformaciones a la luz de la reconstrucción a partir de cortes histológicos seriados. El nódulo sinusal y su irrigación arterial está ubicado en la unión cavoatrial derecha, excepto en corazones con yuxtaposición izquierda de las auriculillas o con alteraciones en imagen en espejo e isoméricas de las aurículas. En presencia de estructuras septales atriales y ventriculares normalmente ubicadas, el tríangulo de Koch es una guía útil para la localización del nódulo atrioventricular y la penetración del haz. En corazones con defectos septales ventriculares aislados es necesario distinguir entre un defecto perimembranoso y un defecto del tracto muscular de entrada. El haz de conducción avanza en el área de continuidad fibrosa sobre el borde posteroinferior de un defecto perimembranoso, en el filo anterosuperior de un defecto del tracto muscular de entrada. En la mayoría de los corazones con tetralogía de Fallot el área de peligro se encuentra en la región del trígono fibroso aórticomitral y tricuspídeo sobre el cual penetra el haz de conducción. En corazones con defectos septales atrioventriculares la falta de continuidad entre el septo atrial y el ventrícular resulta en un desplazamiento posterior del triángulo de Koch y del seno coronario y en una elongación del haz no ramificado. Corazones con nódulos atrioventriculares y haces de conducción anormalmente ubicados son principalmente aquellos con discordancia atrioventricular, con conexión atrioventricular ambigua en presencia de un patrón izquierdo de arquitectura ventricular, corazones con conexión atrioventricular univentricular a un ventrículo morfológicamente izquierdo o indeterminado y corazones con válvula tricuspídea cabalgante. La ubicación del nódulo atrioventricular está determinada por la orientación del septo ventricular y por el patrón de la arquitectura ventricular.

Résumé L'anatomie du système de conduction du coeur normal et du coeur siège de malformations reconstituée à partir de coupes sériées histologiques est exposée. Le sinus nodal et sa vascularisation sont situés au niveau de la partie supérieure de la jonction auriculo-ventriculaire droite sauf dans certains cas: coeur avec juxtaposition des auricules du côté gauche, image en miroir et dispositions isomères des oreillettes. Lorsque les cloisons auriculaire et ventriculaire occupent une situation normale, le triangle de Koch constitue un repère utile pour localiser le noyau auriculo-ventriculaire et le faisceau de His. En cas de défects septaux ventriculaires isolés, il est nécessaire de distinguer les défects périmembraneux et les défects musculaires. L'axe nerveux conducteur chemine dans la zone de continuité fibreuse au bord postéroinférieur du défect périmembraneux mais il chemine au bord antéro-supérieur du défect musculaire. En cas de tétralogie de Fallot, le danger se situe souvent au niveau de la zone fibreuse de continuité aortique-mitrale-tricuspide où pénètre l'axe conducteur. En cas de coeur porteur d'un défect septal auriculo-ventriculaire, le défaut de continuité entre la cloison ventriculaire et la cloison auriculaire entraîne le déplacement postérieur du triangle nodal et du sinus coronaire ainsi que l'élongation du faisceau. Les coeurs qui présentent une anomalie du siège des noyaux auriculo-ventriculaires et des nerfs conducteurs sont principalement ceux qui sont le siège d'une anomalie auriculo-ventriculaire, d'une connexion auriculo-ventriculaire ambiguë en cas d'une disposition ventriculaire de type gauche, d'une connexion auriculo-ventriculaire univentriculaire avec une morphologie ventriculaire gauche ou indeterminée, d'une valve tricuspide en fourche. Le siège du noyau auriculo-ventriculaire est fonction de l'orientation du septum ventriculaire et de l'architecture ventriculaire.


Supported by the British Heart Foundation.  相似文献   
18.
In patients with agenesis of the vagina and cervix but with a functional endometrium, the traditional treatment is hysterectomy with construction of a neovagina. We report successful treatment by laparoscopically assisted full thickness skin graft for reconstruction in a patient with congenital agenesis of the vagina and uterine cervix concomitant with haematometra and ovarian endometrioma in a 12 year old girl. Postoperatively, the vaginal skin graft healed well, and menstruation first appeared 4 weeks later. In our opinion, a combined laparoscopic and vaginal procedure with full thickness skin graft is an efficacious alternative in managing such genital defects.  相似文献   
19.
This study assessed 11C-acetate turnover (clearance) in nasopharyngeal carcinoma (NPC). Data were acquired by dynamic PET after the intravenous injection of 4.625 MBq.kg-1 body weight of 11C-acetate for 30 min. Tomograms were reconstructed and evaluated visually. A time-activity curve of the nasopharynx and neck was generated and the clearance rate of 11C-acetate from the nasopharynx in the slow phase and from NPC was calculated using 0.693/T1/2. Ten patients with nasopharyngeal carcinoma and nine normal subjects were studied. The clearance of 11C-acetate from the normal nasopharynx was rapid and biexponential, in contrast to the rapid uptake followed by extremely slow clearance in patients with NPC. The clearance rate (mean +/- S.D.) was 0.0074 +/- 0.0042 in NPC and 0.0263 +/- 0.0152 in controls in the slow phase, being significantly different between the two groups with no overlap. All nasopharyngeal carcinomas were clearly visualized, in contrast to no obvious retention in the normal nasopharynx. Our initial results indicate that 11C-acetate clearance can be used to differentiate nasopharyngeal carcinoma from a normal nasopharynx. This finding may lead to new applications of 11C-acetate in oncology.  相似文献   
20.
BACKGROUND AND OBJECTIVE: To develop an animal model for evaluation of femtosecond laser intrastromal refractive surgery. METHODS: Intrastromal photodisruption was performed in New Zealand Albino rabbits using a femtosecond laser system. This surgical pattern consisted of a 100 microm-tick pyramid of laser pulses starting 180 microm below the corneal surface. Animals underwent serial slit lamp examinations and corneal thickness measurements at 1,3,7,14, and 28 days, then monthly up to 1 year. RESULTS: Approximately 70 microm of central corneal thinning were seen at 1 week, remaining stable up to 7 months. CONCLUSIONS: Intrastromal photodisruption with femtosecond lasers produced consistent changes in corneal thickness without loss of corneal transparency. These changes were more stable than those produced with excimer laser procedures in a similar animal model.  相似文献   
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