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991.
Adenocarcinoma of the oesophagus and gastro-oesophageal junction are rapidly increasing in incidence and have a well described sequence of carcinogenesis: the Barrett's metaplasia-dysplasia-adenocarcinoma sequence. During recent years there have been changes in the knowledge surrounding disease progression, cancer management and histopathology specimen reporting. Tumours around the gastro-oesophageal junction (GOJ) pose several specific challenges. Numerous difficulties arise when the existing TNM staging systems for gastric and oesophageal cancers are applied to GOJ tumours. The issues facing the current TNM staging and GOJ tumour classification systems are reviewed in this article. Recent evidence regarding the importance of several histopathologically derived prognostic factors, such as circumferential resection margin status and lymph node metastases, have implications for specimen reporting. With the rising use of multimodal treatments for oesophageal cancer it is important that the response of the tumour to this therapy is carefully documented pathologically. In addition, several controversial and novel areas such as endoscopic mucosal resection, lymph node micrometastases and the sentinel node concept are being studied. We aim to review these aspects, with special relevance to oesophageal and gastro-oesophageal cancer specimen reporting, to update the surgical oncologist with an interest in upper gastrointestinal cancer.  相似文献   
992.
Zusammenfassung Nervenfasern, die die optischen Ganglien beider Kopfseiten von Musca und Phaenicia verbinden und die selektiv auf Musterbewegungen antworten, zeigen binoculare Wechselwirkungen. Details dieser Wechselwirkungen und der Ort an dem sie in den optischen Ganglien stattfinden wurden ermittelt. Die Bedeutung dieser Einheiten für die direkte Steuerung von Wendereaktionen beim Flug wurde ebenfalls untersucht.

This research was supported by the National Institutes Health, United States Public Health Service Grant NB 03627.  相似文献   
993.
S ummary . The microbial flora of the thigh adjacent to the vaginal labia and of the mucosal surface of the labia has been examined quantitatively and qualitatively in students from Colleges of Education and a University, and in persons attending a Consultant Gynaecologist for non-suppurative conditions. In the 2 student populations, members of the Micrococcaceae and diphtheroids were the most common organisms but all populations yielded many organisms of gut origin. Differences between the populations may relate to social and hygienic conditions and should make us wary of direct comparisons with other, different populations. The effect of intimate hygiene deodorants containing 0.01% or 0.02% of chlorhexidine was compared with a base spray containing no antibacterial agent. No significant effect of these sprays on the microbial flora could be demonstrated.  相似文献   
994.
995.
Synopsis Observations on the Caribbean sand tilefish, Malacanthus plumieri, were made during 3 dive trips in the Bahamas (Feb., 1986; July, 1986; Jan., 1987) at depths from 5 to 30 m. Eighteen mating groups contained 1 to 5 females (x = 2.9). Seven male home ranges (encompassing female ranges within mating groups) measured 250 to 700 m2. Of 134 paired rises recorded between 1733 and 1925 h EST, 38 had an observed cloud of gametes. Mating times are presented in relation to time of sunset and depth of water. Courtship begins with conspicuous looping behavior of the male as he swims to a female. Close pairing, criss-crossing, and low rises (<1.5 m) often precede a high quivering upward swim (1.5 to 6 m) which culminates in the release of a cloud of gametes at the apex. M. plumieri is compared to the protogynous hermaphroditic razorfishes, Xyrichtys pentadactylus and X. martinicensis, with regard to social organization, size of male home ranges in exposed sandy habitats near coral reefs, sexual size dimorphism, and sex ratio.  相似文献   
996.
Unstimulated monolayer cultures of confluent rabbit periosteal fibroblasts synthesize a factor that stimulates bone resorption in vitro. Furthermore it stimulates rabbit chondrocytes and mouse osteoblasts to synthesize collagenase. The factor has no effect on dead bone in culture, and its activity on live bone is mediated principally by osteoclasts, since it is 75% inhibited by salmon calcitonin. Characterization of the factor by gel filtration and isoelectric focusing indicates an Mr in the range 15 000–25 000 and a pI corresponding to approx. pH 4.7. These biological and physicochemical properties are similar to those reported for a factor released by peripheral blood monocytes. However, whereas human monocyte factor in both the crude and partially-purified state exhibits interleukin-1 activity, crude and fractionated periosteal fibroblast-conditioned medium does not. This is the first report of a conditioned medium containing a molecule like the monocyte-factor which appears to have no interleukin 1 activity. The factor may be synthesized by a wide range of cell types, and could have an important role in mediating connective tissue degradation during both physiological and pathological resorption.  相似文献   
997.
Sixteen male swamp sparrows, Melospiza georgiana, were reared by hand in the laboratory and exposed in infancy to tape-recorded songs. Training ended around 2 months of age. Samples of singing were tape recorded sporadically from the age of 50 to 90 days and on a weekly basis from about 95 to 400 days. Analysis revealed that explicit rehearsal of learned songs did not begin, on the average, until 240 days after the last exposure to training songs. Swamp sparrows can commit song syllables to memory and produce imitations of them 8 months later with no rehearsal in the interim.  相似文献   
998.
999.
Abstract: The subcellular distribution of acyl-CoA: sn -glycerol-3-phosphate O-acyltransferase between brain mitochondria and microsomes was investigated. The activities associated with purified rat brain mitochondrial and microsomal preparations could be distinguished by differences in their acyl-CoA specificity, products of acylation, and sensitivity to N -ethylmaleimide, trypsin, acetone, and polymyxin B. It was concluded that both brain mitochondria and microsomes possess the acyltransferase.  相似文献   
1000.
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