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排序方式: 共有896条查询结果,搜索用时 15 毫秒
1.
Comparison of ThinPrep versus conventional smear cytopreparatory techniques for fine-needle aspiration specimens of head and neck masses. 总被引:2,自引:0,他引:2
Lloyd Ford Barry M Rasgon Raymond L Hilsinger Raul M Cruz Karen Axelsson Gregory J Rumore Thomas M Schmidtknecht Balaram Puligandla John Sawicki William Pshea 《Otolaryngology--head and neck surgery》2002,126(5):554-561
OBJECTIVES: Diagnostic accuracy of the ThinPrep process (Cytyc, Boxborough, MA) was compared with that of conventional (smear) cytopreparation for fine-needle aspiration (FNA) of head and neck masses. METHODS: In a prospective, randomized, single-blinded study, 209 patients served as their own controls and underwent 236 FNAs using ThinPrep and conventional (smear) cytopreparatory techniques. RESULTS: ThinPrep produced less air-drying artifact and less mechanical distortion than the conventional method. The conventional technique was diagnostic in 63% of samples; the ThinPrep technique was diagnostic in 55% of samples. When all results were combined, pathologists subjectively preferred the conventional technique but accepted use of ThinPrep as the only cytopreparatory technique for most head and neck masses. CONCLUSIONS: For adequately experienced cytopathologists, ThinPrep is acceptable for FNA of salivary masses, neck cysts, metastatic lymph nodes, and thyroid lesions. Conventional smear technique should be used for FNA of nonmetastatic lymphoid lesions. Use of ThinPrep can complement use of the conventional (smear) cytopreparatory technique when aspirate is nondiagnostic or bloody, when the patient has a blood-borne infectious disease, when the clinician is inexperienced, or when aspirate has entered the syringe. 相似文献
2.
Frederica Perera Deliang Tang Robin Whyatt Sally Ann Lederman Wieslaw Jedrychowski 《Cancer epidemiology, biomarkers & prevention》2005,14(3):709-714
Polycyclic aromatic hydrocarbons (PAH), of which benzo[a]pyrene is a representative member, are combustion-related environmental pollutants and include known carcinogens. Laboratory animal studies indicate that the dose of PAHs to the fetus is on the order of a 10th that to the mother and that there is heightened susceptibility to PAH-induced carcinogenesis during the fetal and infancy periods. Carcinogen-DNA adducts, a measure of procarcinogenic genetic damage, are considered a biomarker of increased cancer risk. Here we compare the levels of benzo[a]pyrene-DNA adducts as a proxy for PAH-DNA damage measured in maternal blood and newborn cord blood obtained at delivery in four different populations of mothers (total of 867) and newborns (total of 822), representing a 30-fold range of exposure to ambient PAHs. The populations include residents in Northern Manhattan, participants in a study of the effects of the World Trade Center disaster, residents in Krakow, Poland, and residents in Tongliang, China. Mean adduct concentrations in both maternal and cord blood and the proportion of samples with detectable adducts, increased across the populations [Northern Manhattan < World Trade Center (WTC) < Krakow < Tongliang], consistent with the trend in estimated ambient exposure to PAHs (P < 0.001). For mothers, the means in the respective populations were Northern Manhattan (0.21 adducts per 10(8) nucleotides), WTC (0.23 adducts per 10(8) nucleotides), Krakow (0.28 adducts per 10(8) nucleotides), Tongliang (0.31 adducts per 10(8) nucleotides); the corresponding means in the newborns were Northern Manhattan (0.23), WTC (0.24), Krakow (0.29), Tongliang (0.31). The percentage of mothers with detectable levels of adducts in the respective populations were Northern Manhattan (36.8%), WTC (57.5%), Krakow (72.9%), Tongliang (73.4%); the corresponding percentages among the newborns were Northern Manhattan (42.4%), WTC (60.6%), Krakow (71.1%), Tongliang (79.5%). Despite the estimated 10-fold lower PAH dose to the fetus based on laboratory animal experiments, the adduct levels in the newborns were similar to or higher than in the mothers. This study suggests that the fetus may be 10-fold more susceptible to DNA damage than the mother and that in utero exposure to polycyclic aromatic hydrocarbons may disproportionately increase carcinogenic risk. The data support preventive policies to limit PAH exposure to pregnant women and children. 相似文献
3.
4.
Influence of calcitonin treatment on the osteocalcin concentration in the algodystrophy of bone 总被引:1,自引:0,他引:1
A. Sawicki P. Szulc T. Sobczyk J. Goliszewski P. Garnier R. Labuszewski 《Clinical rheumatology》1992,11(3):346-350
Summary Algodystrophy (AD) attacks all tissues in the affected region and results in the rapid demineralization of bones. Osteocalcin (OC) and alkaline phosphatase (AP) are markers of bone turnover. Calcitonin is the treatment of choice of AD. Two groups of patients were studied: Group I (n=8)-acute stage of AD (before and during the calcitonin treatment), Group II (n=5)-late chronic stage of AD. In the acute stage of AD both OC level and AP activity were increased. They were normal in the chronic state of AD. During the calcitonin treatment OC level normalized after 14 days and then increased again. During the treatment, AP activity temporarily increased and then returned to the initial level. We confirm that an increased bone turnover is observed in the acute stage of AD. Discrepancy between OC level and AP activity reflects the local metabolic disturbances. Salmon calcitonin inhibits the algodystrophic process and probably contributes to the activation of the skeletal restoration. 相似文献
5.
The ascending colon of a guinea pig injected with tritiated thymidine was cut serially, autoradiographed and stained with periodic-acid-Schiff-hematoxylin. Maps of transversely sectioned crypts were prepared with the use of a microscope eye-piece projector. The number and angular positions of pulselabelled (DNA-synthesizing) cells around the circumference of transverse sections of the crypt were recorded. A method of “statistics of the circumference” was applied in order to find the variances of angular distances between labelled cells and thereby to find the type of arrangement of DNA-synthesizinbg cells in the crypt. The spatial distribution of DNA-synthesizing cells, both around the crypt circumference and along the crypt, was found to be non-random. While the pattern of nonrandomness around the crypt circumference is such that the DNA-synthesizing cells tend to occupy positions in the crypt circumference at maximal distances from each other, DNA-synthesizing cells along the crypt tend to occupy positions at minimal distances from each other. DNA-synthesizing cells are arranged in the crypt in rows, each consisting of several cells and each parallel to the long axis of the crypt. Apparently the dividing cell of the crypt produces either two proliferating or two differentiating cells. No evidence of differential mitosis could be found. 相似文献
6.
Wieslaw W. Pawlik Piotr Gustaw Eugene D. Jacobson Ryszard Sendur Krzysztof Czarnobilski 《Pflügers Archiv : European journal of physiology》1995,429(3):301-305
It has long been recognized that intestinal blood flow increases at mealtimes. Mesenteric hyperaemia is also evoked by activation of sensory peptidergic nerves. Our studies explored the possible role of endogenous nitric oxide (NO) in the rat intestinal vasodilator response to luminal instillation of an oleic acid plus bile mixture before and after acute intrajejunal instillation of capsaicin and after chronic pretreatment with capsaicin. In anaesthetized rats we measured jejunal blood flow (BF) with an ultrasonic Doppler flowmeter and systemic arterial pressure (AP) with a pressure transducer. Intestinal perfusion with 80 mM oleic acid in bile increased BF by 98±12%. Instillation of 4 mg of capsaicin into the jejunal lumen initially increased BF by 42±9% but was followed by vasoconstriction. Inhibition of NO synthase with 25 mg/kg i.v. N-nitro-L-arginine (L-NNA) decreased BF by 27±5% and increased AP by 37±11%. After treatment with L-NNA and after acute and chronic administration of capsaicin, the bile-oleate-induced maximal increases in BF above control levels were 42±7%, 65±12%, and 58±8%, respectively. The observed inhibitory effect of L-NNA on the intestinal hyperaemic response to the bile-oleate mixture was reversed by pretreatment with L-arginine (100 mg/kg i.V.). In capsaicin pretreated rats the subsequent bile-oleate-induced hyperaemia was reduced in magnitude but the inhibitory effects of L-NNA were proportionately the same as in animals not receiving capsaicin. These findings support the hypothesis that NO is involved with bile-oleate-induced mesenteric hyperaemia. 相似文献
7.
Differential regulation of platelet aggregation by matrix metalloproteinases-9 and -2 总被引:10,自引:0,他引:10
Fernandez-Patron C Martinez-Cuesta MA Salas E Sawicki G Wozniak M Radomski MW Davidge ST 《Thrombosis and haemostasis》1999,82(6):1730-1735
We have recently found matrix metalloproteinase-2 (MMP-2) in human platelets and reported that the release of this enzyme during platelet activation stimulates aggregation. We have now identified matrix metalloproteinase-9 (MMP-9) in human platelets and resistance-sized (approximately 200 microm) arteries. Resting platelets released small quantities of pro-MMP-9. Maximal release of MMP-9 was detected during partial (appr. 30% maximum) aggregation with thrombin. However, maximal release of MMP-2 was associated with maximal aggregation. MMP-9 antibodies induced aggregation of resting platelets and potentiated aggregation of platelets induced by thrombin and collagen. Moreover, MMP-9 microisolated from arteries as well as recombinant human MMP-9 (0.1-30 ng/ml) inhibited thrombin and collagen-induced aggregation. We conclude that MMP-9 is an inhibitor of aggregation and in this action opposes the effects of MMP-2. The MMP-2/MMP-9 system may play an important role in the regulation of platelet-platelet and platelet-vessel wall interactions. 相似文献
8.
Hennig Ewa E.; Demkowicz-Dobrzanski Krzysztof K.; Sawicki Jozef T.; Mojska Hanna; Kujawa Marek 《Carcinogenesis》1983,4(10):1243-1246
The effect of butylated hydroxyanisole (BHA) administrationon the hepatic monooxygenase system of nuclear and microsomalfraction was investigated in male mice. Addition of BHA to thediet significantly lowered the content of cytochrome P-450 inliver nuclei and increased the specific activity of NADPH-cytochromec reductase and the content of cytochrome b5 in liver microsomes.Incubation of benzo[a]pyrene (BP) with liver nuclei from BHA-fedmice resulted in inhibition of binding of BP metabolites tonuclear macromolecules by 50% compared with control. However,there was no effect of BHA on the binding of BP metabolitesto macromolecules when BP was incubated with added DNA and livermicrosomes from BHA-fed mice. It has been postulated that modificationof nuclear monooxygenases by BHA may play a role in the inhibitoryeffect of BHA on BP carcinogenesis. 相似文献
9.
Compressibility of floating pellets with verapamil hydrochloride coated with dispersion Kollicoat SR 30 D. 总被引:4,自引:0,他引:4
Wies?aw Sawicki Rafa? Lunio 《European journal of pharmaceutics and biopharmaceutics》2005,60(1):153-158
The purpose of this study was to work out a method of compression of floating pellets with verapamil hydrochloride (VH) in a dose of 40 mg. It was assumed that this form should reside in the stomach floating for several hours and gradually release the drug in a controlled way. Compression of pellets into tablets, being a modern technological process, is much more perfect than enclosing them in a hard gelatin capsule. Kollicoat SR 30 D was selected for coating. In experiments three plasticizers were examined-propylene glycol, triethyl citrate and dibuthyl sebecate (all at concentration of 10%). It was found that VH release from pellets coated by the films of the same thickness (70 microm), however, containing plasticizers is considerably different. Pellets were prepared by wet granulation of powder mixture, spheronization of the granulated mass and coating of the cores with a sustained release film. Two kinds of cellulose, microcrystalline and powdered, and sodium hydrocarbonate were the main components of pellet core. Proper pellet coating film thickness, ensuring obtaining desirable VH release profile and flotation effect, was defined. X compositions of tablets with pellets were examined in order to obtain formulation, from which VH release would mostly approximate pellets before compressing. The best formulation was evaluated taking into account the effect of compression force an tablet hardness and friability, and pellet agglomeration and flotation. Tablet cross-section photographs were taken confirming necessary coating film thickness preventing their deformation caused by compressing into tablets. 相似文献
10.
Wieslaw Slosarz 《Sexual and Relationship Therapy》2013,28(3):267-273
Psychological factors play the most important role in the genesis of sexual dysfunction and the role of psychologists in the prevention, diagnosis, and treatment of these dysfunctions is therefore considerable. This article discusses some of the psychological factors that accompnay erectile ejaculatory cysfunction as well as the possible psychological mechanisms that can occur during the development of these dysfunctions. 相似文献