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31.
Tse GM  To EW  Yuen EH  Chen M 《Acta cytologica》2001,45(5):775-778
BACKGROUND: Basal cell adenocarcinoma of the parotid is rare and prone to recur. CASE: A 54-year-old woman had a history of afacial mass 12 years earlier that had been excised and was diagnosed as low grade adenocarcinoma of the parotid. Over the years, the patient had multiple local and lymph node recurrences. Histology of the excised local recurrent tumor showed basal cell adenocarcinoma, and FNAC of a separate recurrent nodule was performed. The aspirate showed moderate cellularity of basaloid cells with mildly pleomorphic nuclei, small nucleoli and occasional mitotic figures. The cells were mostly single, but some formed clusters with a rosettelike pattern of tumor cells surrounding central eosinophilic globules. A second, less prominent population of smaller cells with dark-staining nuclei was also noted. The differential diagnosis included adenoid cystic carcinoma, polymorphous low grade adenocarcinoma, and basal cell and pleomorphic adenoma. CONCLUSION: The cytologic features of basal cell adenocarcinoma are not distinctive, but the presence of two cell populations with moderate pleomorphism and a rosettelike pattern with central, eosinophilic globules may assist with its differentiation from other salivary gland neoplasms.  相似文献   
32.
We investigated whether supplementation of a sunscreen containing the UVB absorber 2-ethyl-hexyl-methoxycinnamate (cinnamate) with oxygen radical inhibitors (ORI) would improve protection from sunburn, immunosuppression and carcinogenesis. Mice were exposed to solar-simulated UV radiation (ssUV) containing a mixture of UVB and UVA. In initial studies, the ORI 2,2'-dipyridyl and N(G)-monomethyl-L-arginine acetate (L-NMMA) were shown to prevent UVA-induced suppression of contact sensitivity (CS) in mice. Addition of these inhibitors to the sunscreen did not affect the sun protection factor (SPF), but lowered the level of edema when mice were exposed to ssUV. Combination of both inhibitors with the sunscreen, however, increased the SPF from 5 to 5.5. The immune protection factor (IPF) of the sunscreen was only 1.18, but addition of neither dipyridyl nor L-NMMA singly or in combination measurably improved immune protection. However, the ORI improved the ability of the sunscreen to prevent carcinogenesis. The results indicate that reactive oxygen or nitrogen species produced in response to UV radiation are important for erythema, immunosuppression and carcinogenesis, and addition of inhibitors improves the protective capacity of sunscreens.  相似文献   
33.
A wide variety of vanadium-containing complexes have been tested, both in vivo and in vitro, as possible therapeutic agents for the oral treatment of type 2 diabetes mellitus. None so far has surpassed bis(maltolato)oxovanadium(IV) (BMOV) for glucose- and lipid-lowering in an orally available formulation. Ligand choice is clearly an important factor in pharmacological efficacy of vanadium compounds as insulin enhancing agents. In this study, we kept the ligand and dose the same, varying instead the metal ion bound to the maltolato ligand in a series of binary complexes of neutral charge. A requirement for vanadyl ion as the metal ion of choice was apparent; no other metal ion tested served as a suitable substitute. Amongst [MoO(2)](2+), Co(II), Cu(II), Cr(III), and Zn(II), only [MoO(2)](2+) and Co(II) showed any hypoglycemic activity at the ED(50) dose for bis(maltolato)oxovanadium(IV), 0.6 mmolkg(-1) by oral gavage in streptozotocin (STZ)-diabetic rats within 72 h of administration of compound.  相似文献   
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We applied RNA arbitrarily primed-PCR (RAP-PCR) to screen the genes differentially expressed between common congenital heart defects (CHD) [atrial septal defect, ventricular septal defect, Tetrology of Fallot (TOF)] and normal human heart samples. Three of these differentially amplified fragments matched cDNA sequences coding for proteins of unknown function in humans: hCALO (human homologue of calossin), NP79 (coding for a nuclear protein of 79KD) and SUN2 (Sad-1 unc-84 domain protein 2). The other four fragments were from known human genes: apolipoprotein J, titin, dystrophin and protein kinase C-delta. Northern blot analysis confirmed that all of these genes are expressed in the human heart. The results of RAP-PCR were reconfirmed by quantitative RT-PCR in TOF and control heart samples. Both techniques showed the levels of expression of hCALO, NP79 and SUN2 to be comparable in TOF and control samples and the level of expression of dystrophin and titin, both coding for cytoskeletal proteins, to be significantly upregulated in TOF samples. In summary, we have shown that the RAP-PCR technique is useful in the identification of differentially expressed gene from biopsy samples of human CHD tissues. In this manner, we have identified three novel genes implicated in the normal function of the human heart and two known genes upregulated in TOF samples.  相似文献   
36.
Field and laboratory experiments compared the feeding behaviours of two marine scavengers, the gastropod, Nassarius festivus and the hermit crab, Diogenes edwardsii, sympatric on the lower intertidal shore at Starfish Bay, Hong Kong. Field trials demonstrated that they both preferred bivalve and fish to other carrion. N. festivus arrived at bait in greater numbers and more quickly than D. edwardsii. Numbers of the former species attracted to fish bait (1 cm(3)) peaked at a mean of 41 after 30 min, whereas the latter peaked at a mean of only 2.3 after 55 min. Laboratory investigations revealed that N. festivus80 cm, feed quickly (x=13.20 min) and, after 14 days starvation, had a high consumption rate (0.124 mg wet weight or 0.034 mg dry weight of food individual(-1) min(-1), or 1.4% and 1.3% of its wet and dry body weights min(-1), respectively). In contrast, D. edwardsii119.75 min and a lower consumption rate (0.003 mg wet weight and 0.001 mg dry weight of food individual(-1) min(-1), or 0.1% of its wet and dry body weights min(-1), respectively). Manipulative experiments provided evidence for interspecific competition for carrion between the two species. A morphological advantage, i.e. an extendible proboscis allowing feeding at a distance, and chemoreceptors that permit long distance food detection, combined with numerical superiority on the shore, are mechanisms by which N. festivus outcompetes D. edwardsii and dominates feeding clusters. Interactive behaviour studies revealed the occurrence of interspecific interactions between the two species and intraspecific interactions among D. edwardsii but not N. festivus. The number of interspecific interactions fell when the numbers of N. festivus increased and those of D. edwardsii decreased, and vice versa. The aggressive D. edwardsii did not significantly affect the feeding behaviour of N. festivus. When the number of D. edwardsii increased and the number of N. festivus decreased, the number of intraspecific interactions in the former increased. The feeding time of N. festivus, however, decreased with increasing numbers of conspecifics and a decreasing number of D. edwardsii. This suggests the possibility of intraspecific competition in N. festivus.  相似文献   
37.
Over a 5-year period, 232 microvascular composite-tissue transfers to the head and neck, trunk, and extremities were monitored using the laser Doppler flowmeter. Thirteen free flaps (5.6 percent) developed vascular complications, all within 4 days after surgery. The laser Doppler flowmeter detected vascular compromise in all cases with no false positives or negatives. Failure to monitor the flap according to protocol by nursing staff occurred in one patient, which led to a delay in detection of venous compromise and subsequent flap loss. The salvage rate was 69.2 percent, leading to an overall flap viability of 98.3 percent. Our series of free-flap monitoring using the laser Doppler flowmeter is the largest reported to date. Review of the English literature shows consistent support by numerous clinical series for the use of the laser Doppler as a valuable postoperative monitor after free-flap transfers.  相似文献   
38.
A simple high-performance liquid chromatographic method using fluorescence detection was developed for the determination of ketoconazole in human plasma. The method entailed direct injection of the plasma sample after deproteinization using acetonitrile. The mobile phase comprised 0.05 M disodium hydrogen orthophosphate and acetonitrile (50:50, v/v) adjusted to pH 6. Analysis was run at a flow-rate of 1.5 ml/min with the detector operating at an excitation wavelength of 260 nm and an emission wavelength of 375 nm. The method is specific and sensitive with a quantification limit of approximately 60 ng/ml and a detection limit of 40 ng/ml at a signal-to-noise ratio of 3:1. Mean absolute recovery value was about 105%, while the within-day and between-day coefficient of variation and percent error values of the assay method were all less than 14%. The calibration curve was linear over a concentration range of 62.5–8000 ng/ml.  相似文献   
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A molecular test for Alzheimer's disease could lead to better treatment and therapies. We found 18 signaling proteins in blood plasma that can be used to classify blinded samples from Alzheimer's and control subjects with close to 90% accuracy and to identify patients who had mild cognitive impairment that progressed to Alzheimer's disease 2-6 years later. Biological analysis of the 18 proteins points to systemic dysregulation of hematopoiesis, immune responses, apoptosis and neuronal support in presymptomatic Alzheimer's disease.  相似文献   
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