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91.
Fully automated, internally controlled quantification of hepatitis B Virus DNA by real-time PCR by use of the MagNA Pure LC and LightCycler instruments 总被引:3,自引:0,他引:3
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Leb V Stöcher M Valentine-Thon E Hölzl G Kessler H Stekel H Berg J 《Journal of clinical microbiology》2004,42(2):585-590
We report on the development of a fully automated real-time PCR assay for the quantitative detection of hepatitis B virus (HBV) DNA in plasma with EDTA (EDTA plasma). The MagNA Pure LC instrument was used for automated DNA purification and automated preparation of PCR mixtures. Real-time PCR was performed on the LightCycler instrument. An internal amplification control was devised as a PCR competitor and was introduced into the assay at the stage of DNA purification to permit monitoring for sample adequacy. The detection limit of the assay was found to be 200 HBV DNA copies/ml, with a linear dynamic range of 8 orders of magnitude. When samples from the European Union Quality Control Concerted Action HBV Proficiency Panel 1999 were examined, the results were found to be in acceptable agreement with the HBV DNA concentrations of the panel members. In a clinical laboratory evaluation of 123 EDTA plasma samples, a significant correlation was found with the results obtained by the Roche HBV Monitor test on the Cobas Amplicor analyzer within the dynamic range of that system. In conclusion, the newly developed assay has a markedly reduced hands-on time, permits monitoring for sample adequacy, and is suitable for the quantitative detection of HBV DNA in plasma in a routine clinical laboratory. 相似文献
92.
A 53-yr-old woman presented with a left upper quadrant abdominal mass attached to the body of the pancreas. Fine-needle aspiration (FNA) yielded cyst fluid containing numerous benign, mature squamous cells, keratin debris, and inflammatory cells. The diagnosis of dermoid cyst was subsequently rendered on the resected specimen. The cytologic and histologic features are presented. FNA cytology proves to be a valuable diagnostic adjunct in the preoperative evaluation of a patient with dermoid cyst of the pancreas. 相似文献
93.
P J Lamey R E Leake S K Cowan D S Soutar I A McGregor F M McGregor 《Journal of clinical pathology》1987,40(5):532-534
Major salivary gland tumours were studied for the presence of hormone receptors for oestrogen and progesterone. Of the eight salivary gland tumours exhibiting varied histology, none showed high affinity receptors for oestrogen or progesterone. Salivary tissue from four patients with non-neoplastic salivary gland disease was also studied and found not to contain high affinity receptor sites. The absence of hormone receptors in these glands suggests that such tumours are not dependent on endocrine function. 相似文献
94.
Victoria Chan-Palay 《Anatomy and embryology》1973,142(2):149-186
Summary Axon terminals in the neuropil of the lateral nucleus can be divided into six classes, each with a specific constellation of characteristics that consistently occur together. Two of these classes have synaptic varicosities with elliptical synaptic vesicles, one in a dense, the other in a sparse matrix, and both make axosomatic and axodendritic synapses. The remaining four classes all have round synaptic vesicles and do not make axosomatic synapses. In the first of these four, the vesicles are tightly packed in a dense matrix, in another they are loosely dispersed, and in the third they are clustered. In the fourth, large granular vesicles predominate. Of these six classes, the most numerous belong to the axons of the Purkinje cell terminal arborization. These boutons resemble their counterparts in the cerebellar cortex, the recurrent collaterals of the Purkinje axon. They have elliptical and flat synaptic vesicles in a dark matrix. The varicosities terminate on somata and dendrites of large and small neurons and constitute the majority of their input. Purkinje axons constitute 86% of the total population of terminals on large neuronal perikarya and 50% of those on their dendrites, but only 78% on the somata of small neurons and 31% on their dendrites. The terminals of climbing fiber collaterals are recognized by their resemblance in electron micrographs to the terminals of the climbing fiber arborization in the cerebellar cortex. They bear round synaptic vesicles packed into a dense axoplasmic matrix and make Gray's type 1 axodendritic synapses with large and small neurons. These axons are restricted to the lateral and ventral aspects of the nucleus and constitute 5% of the terminals on large cell dendrites and 6% of those on small neurons. The axons tentatively identified as collaterals of mossy fibers are myelinated fibers with a light axoplasm containing round synaptic vesicles, dispersed throughout their varicosities. They make Gray's type 1 synapses and constitute a fair percentage of the total axodendritic contacts in the neuropil, 22% on large neurons and 28% on small neurons. The bases for these tentative identifications are discussed in detail, as are the various synaptic relationships undertaken by each class of axon. The remaining 4 classes of axons of the neuropil will be described in subsequent papers.Supported in part by U.S. Public Health Service grants NS 10536 and NS 03659, Training grant NS 05591 from the National Institute of Neurological Diseases and Stroke, and a William F. Milton Fund Award from Harvard University. 相似文献
95.
Fuentes V Toledano M Osorio R Carvalho RM 《Journal of biomedical materials research. Part A》2003,66(4):850-853
Our purpose in this study was to determine the microhardness of superficial and deep dentin by means of two indentation methods (Knoop and Vickers) under two different applied loads. Twelve dentin discs approximately 2-mm thick were obtained from both superficial and deep dentin by transversally sectioning the crowns of sound, extracted human third molars with a diamond blade under water irrigation. Dentin surfaces were sequentially polished, and indentations (n = 20 per surface) were performed with either Vickers indentor at loads of 300 and 500 g, respectively, or Knoop indentor at loads of 50 and 100 g, respectively. Average Vickers hardness number (VHN) and Knoop hardness number (KHN) were calculated and treated with two-way analysis of variance (ANOVA) and Student's t test. Microhardness of dentin was not influenced by the different loads applied for both indentation methods. Knoop hardness was significantly higher for superficial than for deep dentin (p < 0.05). Conversely, Vickers hardness was not significantly different for both substrates (p > 0.05). Differences in dentin hardness as a function of depth exist, but they might not be relevant, and no alteration of the distribution of stresses along the adhesive interface is expected. 相似文献
96.
The effect of a competitive soccer match on maximal power performance was assessed on 19 members of an NCAA Division III female soccer team. Performance testing occurred within 24 hours prior to the game (Pre), immediately postgame (IP), and 24 hours postgame (24P). Each subject performed a squat jump (SJ) and countermovement jump (CMJ). Comparisons between starters (n = 10) and nonstarters (n = 9) revealed no between-group differences in power performance at IP, but starters were found to have significantly lower power and force measures at 24P than nonstarters. There were significant correlations between playing time and peak force during the SJ at 24P (r = -0.47), and between playing time and peak power during the SJ at IP (r = -0.57) and 24P (r = -0.51), and during the CMJ at IP (r = -0.49). Comparisons between different positions revealed no differential fatigue patterns. Results of this study show that power performance appears to be maintained for the duration of a soccer match but declines significantly within 24 hours after the match. Position played does not appear to affect performance decrements seen at 24 hours postmatch. 相似文献
97.
Chorneyko K Giesler R Sabatino D Ross C Lobo F Shuhaibar H Chen V Elavathil L Denardi F Ansari S Salama S LeBlanc V Norman G Sheridan B Riddell R 《American journal of clinical pathology》2002,117(5):783-790
Telepathology (TP) uses telecommunication linkages to electronically capture, store, retrieve, and transmit images to distant sites. We assessed the feasibility of a dynamic real-time TP system for light microscopic (LM) diagnosis of anatomic pathology specimens, including frozen sections. Six pathologists, in 2 separate periods, read a set of 160 retrospectively retrieved slides (80 of which were frozen sections) by TP and LM. Reading times were recorded. Diagnoses were compared with the reference diagnosis (established by a group of 5 independent pathologists) and graded on a scale of 0 to 2 (2, correct; 1, incorrect but no clinical impact; 0, incorrect with clinical impact). Overall, LM was more accurate than TP compared with the reference diagnosis (score, 1.68 vs 1.54). There was no difference in accuracy between frozen section and paraffin-embedded tissue. Intraobserver agreement ranged from 82.5% to 88.2%. The average reading time was 6.0 minutes for TP and 1.4 minutes for LM. During the study, reading time decreased for TP but not for LM. These results show that despite marginally lower accuracy and longer reading times, TP isfeasible for routine light microscopic diagnosis, including frozen sections. 相似文献
98.
Adhesion molecules play a crucial part in cell-matrix and in cell-cell interactions. These interactions, which are essential to the body's defense processes, involve adhesion molecules belonging to different families: integrins, immunoglobulins and selectins. Integrins are expressed by a large number of tissues, whereas other adhesion molecule families are restricted to a small number of cell types. A recent symposium dealt with the recruitment of circulating platelets at specific sites, their adhesion to extracellular matrix components and their activation by agonists leading to aggregation or attachment to other cells. These events, supporting hemostasis and thrombosis, involve integrins, selectins and other adhesion molecules. This report focuses on newly reported integrins (GPIa, GPIc, GPIIa), selectins (GMP-140) and GPIIIb, previously known as 'minor' surface oriented platelet glycoproteins. Major membrane glycoproteins such as GPIIb-IIIa (an integrin) and GPIb, which also play a vital role in platelet functions, have been extensively reviewed elsewhere. 相似文献
99.
Barbara H. Bowman Lillian H. Lockhart Victoria L. Herzberg Don R. Barnett Donald Armstrong John Kramer 《Clinical genetics》1973,4(6):461-463
The presence of a ciliary inhibitor in media of cultured amniotic cells obtained from a fetus heterozygous for cystic fibrosis has been observed by the oyster gill cilia assay. The chromatographic fraction containing the inhibitor corresponded to eluted fractions chromatographed from cystic fibrosis fibroblast media and serum. An analogous chromatographic fraction from media of cultured amniotic cells from two proportedly normal fetuses did not inhibit cilia. The chromatographic fraction from media of cultured amniotic cells of a fetus at high risk for cystic fibrosis did not inhibit ciliary activity. Serum was collected from this baby seven weeks after birth and also did not inhibit ciliary action, indicating a homozygous normal genotype. These observations may lead to the development of an antenatal test for cystic fibrosis. 相似文献
100.
Fibrinogen stabilizes placental-maternal attachment during embryonic development in the mouse 总被引:9,自引:0,他引:9
Iwaki T Sandoval-Cooper MJ Paiva M Kobayashi T Ploplis VA Castellino FJ 《The American journal of pathology》2002,160(3):1021-1034
In humans, maternal fibrinogen (Fg) is required to support pregnancies by maintaining hemostatic balance and stabilizing uteroplacental attachment at the fibrinoid layer found at the fetal-maternal junction. To examine relationships between low Fg levels and early fetal loss, a genetic model of afibrinogenemia was developed. Pregnant mice homozygous for a deletion of the Fg-gamma chain, which results in a total Fg deficiency state (FG(-/-)), aborted the fetuses at the equivalent gestational stage seen in humans. Results obtained from timed matings of FG(-/-) mice showed that vaginal bleeding was initiated as early as embryonic day (E)6 to 7, a critical stage for maternal-fetal vascular development. The condition of afibrinogenemia retarded embryo-placental development, and consistently led to abortion and maternal death at E9.75. Lack of Fg did not alter the extent or distribution pattern of other putative factors of embryo-placental attachment, including laminin, fibronectin, and Factor XIII, indicating that the presence of fibrin(ogen) is required to confer sufficient stability at the placental-decidual interface. The results of these studies demonstrate that maternal Fg plays a critical role in maintenance of pregnancy in mice, both by supporting proper development of fetal-maternal vascular communication and stabilization of embryo implantation. 相似文献