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101.
102.
World Workshop on Oral Medicine VI: a systematic review of medication‐induced salivary gland dysfunction 下载免费PDF全文
A Villa A Wolff N Narayana C Dawes DJ Aframian AM Lynge Pedersen A Vissink A Aliko YW Sia RK Joshi R McGowan SB Jensen AR Kerr J Ekström G Proctor 《Oral diseases》2016,22(5):365-382
The aim of this paper was to perform a systematic review of the pathogenesis of medication‐induced salivary gland dysfunction (MISGD). Review of the identified papers was based on the standards regarding the methodology for systematic reviews set forth by the World Workshop on Oral Medicine IV and the PRISMA statement. Eligible papers were assessed for both the degree and strength of relevance to the pathogenesis of MISGD as well as on the appropriateness of the study design and sample size. A total of 99 papers were retained for the final analysis. MISGD in human studies was generally reported as xerostomia (the sensation of oral dryness) without measurements of salivary secretion rate. Medications may act on the central nervous system (CNS) and/or at the neuroglandular junction on muscarinic, α‐and β‐adrenergic receptors and certain peptidergic receptors. The types of medications that were most commonly implicated for inducing salivary gland dysfunction were those acting on the nervous, cardiovascular, genitourinary, musculoskeletal, respiratory, and alimentary systems. Although many medications may affect the salivary flow rate and composition, most of the studies considered only xerostomia. Thus, further human studies are necessary to improve our understanding of the association between MISGD and the underlying pathophysiology. 相似文献
103.
Heterogeneity of large granular lymphocyte proliferations: delineation of two major subtypes 总被引:5,自引:0,他引:5
Two major types of lymphocytosis of large granular lymphocytes (LGLs) were observed. The proliferating LGLs in each type had distinct immunophenotypes, functional characteristics, and probably belonged to different cell lineages. The more common form (Type A) consisted of cells derived from the T cell lineage and had the T suppressor/cytotoxic phenotype (T11+, T3+, T8+). The expression of the Leu 7 and HLA-DR antigen was variable. These cells did not have natural killer (NK) function but showed a variable degree of antibody-dependent cell-mediated cytotoxic (ADCC) activity. Neutropenia was invariably present and rheumatoid arthritis and autoantibodies were frequent associations. These lymphocytes had many similarities to the major type of LGLs present in normal adult bone marrow. The other type of LGL lymphocytosis (Type B) consisted of cells lacking the antigens T3 and T8 but expressing M1 and NKH1. These cells possessed strong NK and ADCC activity but their cell lineage was not clear. Neutropenia and autoimmune phenomena were not detected. The cytochemical characteristics of the LGL granules from both types of patients were similar but differences in ultrastructure were observed. LGLs from Type B patients proliferated in the presence of Interleukin 2 (IL-2) and 12- O-tetradecanoyl-phorbol-13 acetate (TPA). Significant changes in their basic T11+, T3-, T8- phenotype were not observed. IL-2 and TPA, however, had profound influence on the NK function of the cells with enhancement in the case of IL-2 and marked suppression when stimulated by TPA. 相似文献
104.
105.
Background: Calcium channel blockers potentiate the effects of local anaesthetics. We examined the effect of adding verapamil to local anaesthetic solution on anaesthetic duration in patients undergoing surgery under brachial plexus block. 相似文献
106.
Marianne Frieri Jaya Therattil Deborah Dellavecchia Susan Rockitter Jeff Pettit Myron Zitt 《The Journal of asthma》2002,39(5):405-412
Allergy immunology specialists (AIs) differ from primary care physicians (PCP) in their treatment of asthma. A limited retrospective chart review of several visits over a 1-year period in 1997 evaluating the quality of asthma care by AIs vs. PCPs was conducted in an academic center. Data concerning quality, effectiveness and cost of asthma care was randomly collected from 15 AIs and 15 PCPs from charts at 3-month intervals over a 1-year period. Information obtained from data collection forms revealed that asthma patients evaluated by AIs had more visits and received a greater quantity of medication compared to those treated by PCPs. All 15 patients with persistent asthma followed by AIs were treated with inhaled corticosteroids at each visit in contrast to only 80% of those treated by PCPs. The total numbers of controller medications (i.e., inhaled corticosteroids, salmeterol, cromolyn, and theophylline) that were utilized, as recommended, by the National Asthma Expert Panel (NAEP) of the National Heart, Lung, and Blood Institute (NHLBI) guidelines were 70 by AIs vs. 24 by PCPs over three visits. Cromolyn was prescribed five times over three visits by AIs and not at all by PCPs. Recognition and treatment of coexisting allergic rhinitis was evident in only 13% of patients treated by PCPs as compared to 80% in those treated by AIS. (p < 0.0001). However, all patients treated by AIs were skin tested to explore the presence of allergic triggers, while no patients treated by PCPs were evaluated for IgE-mediated reactions. Treatment cost for allergic rhinitis was therefore higher, at $2039, for AIs as compared to $741 for PCPs. There were no peakflow values in charts obtained from PCPs. However, all charts from AIs had peakflow values, which improved during the course of therapy in 33% of patients. Total medication costs for asthma were higher for AIs @ $5,646.30 vs. $1,932.25 for PCPs. Total medication costs for allergic rhinitis plus asthma were higher for AIs @ $7615 vs. $2681 for PCPs. However, patients treated by AIs had more severe asthma and required more frequent visits. Ipratropium bromide was prescribed a total of four times over several visits by PCPs vs. only once by AIs. In comparing asthma care between AI specialists and PCPs, it was found that AI specialists treat more severe asthmatics, provide more frequent follow-up visits, utilize peak flow rates, prescribe more controller medications, and more often recognize and treat comorbid conditions such as allergic rhinitis that impact on asthma care. Thus, although treatment costs for AIs are higher, these costs are justified by a quality of care that is more consistent with national (NHLBI) guidelines. 相似文献
107.
Bioassay-guided (P388 lymphocytic leukemia cell line) separation of a CH2Cl2/MeOH extract of Lychnophora antillana led to the isolation of two cytostatic (P-388, ED50 2.0 and 0.19 micrograms/ml, respectively) germacranolides designated lychnostatins 1 [1] and 2 [2]. Structural elucidation was based initially upon high field (400 MHz) nmr and electron impact mass spectral interpretations and unequivocally completed by X-ray crystal structure determinations. 相似文献
108.
Antineoplastic agents, 120. Pancratium littorale 总被引:2,自引:0,他引:2
G R Pettit V Gaddamidi D L Herald S B Singh G M Cragg J M Schmidt F E Boettner M Williams Y Sagawa 《Journal of natural products》1986,49(6):995-1002
The bulbs of Pancratium littorale collected in Hawaii were found to contain a new phenanthridone biosynthetic product designated pancratistatin (4a) that proved to be effective (38-106% life extension at 0.75-12.5 mg/kg dose levels) against the murine P-388 lymphocytic leukemia. Pancratistatin also markedly inhibited (ED50, 0.01 microgram/ml) growth of the P-388 in vitro cell line and in vivo murine M-5076 ovary sarcoma (53-84% life extension at 0.38-3.0 mg/kg). An X-ray crystal structure determination of pancratistatin monomethyl ether (4c) and a detailed high resolution (400 MHz) nmr study of pancratistatin and its pentaacetate (4b) completed assignment of structure 4a. Companion antineoplastic constituents of P. littorale were found to be narciclasine (2c) and its 7-deoxy derivative (2a). The structure of 7-deoxynarciclasine (2c) was also confirmed by an X-ray crystallographic analysis. 相似文献
109.
Delayed hepatic CT scanning: increased confidence and improved detection of hepatic metastases 总被引:1,自引:0,他引:1
Bernardino ME; Erwin BC; Steinberg HV; Baumgartner BR; Torres WE; Gedgaudas- McClees RK 《Radiology》1986,159(1):71-74
Fifty oncologic patients with suspected hepatic metastases were prospectively evaluated by dynamic sequential hepatic computed tomography (DSHCT) and by delayed iodine hepatic computed tomography (DICT) scanning. DICT scanning was performed 4-6 hours following administration of 60 g of intravenous iodine. Both techniques were evaluated for lesion definition relative to the adjacent hepatic parenchyma and for numbers of metastases detected. Metastases were detected by both techniques in 26 patients. Fifteen patients (58%) had lesions better defined by DICT. DICT scanning detected more metastases in seven of these 15 patients. In eight patients (31%), there was no difference between the two techniques in numbers of masses detected or lesion definition. In three cases (11%), metastases were more confidently identified on the initial or DSHCT scan. DICT scanning, as described, is useful in defining and detecting hepatic metastases, especially where there is questionable hepatic involvement or better quantification of size is necessary. 相似文献
110.
Sanaa M Nabha Ramzi M Mohammad Mahmoud H Dandashi Brigitte Coupaye-Gerard Amro Aboukameel George R Pettit Ayad M Al-Katib 《Clinical cancer research》2002,8(8):2735-2741
We have previously reported that combretastatin-A4 prodrug (CA4P), anantitubulin/antiangiogenic agent isolated from the South African willow tree Combretum caffrum, induced cell death primarily through mitotic catastrophe in a panel of human B-lymphoid tumors. In this study, we investigated the molecular aspects of the mitotic catastrophe and whether or not it shares the same pathways of apoptosis. For this we studied the effect of CA4P on selected markers of apoptosis [caspases 9 and 3, poly(ADP-ribose) polymerase (PARP), bcl-2, and bax] and G2-M protein regulators (p53, MDM2, 14-3-3sigma, GADD45, cdc2, cdc25, chk1, wee1, p21, and cyclin B1). The chronic lymphocytic leukemia cell line WSU-CLL was used for this purpose. Western blot analysis showed that 24 h of CA4P (5 nM) exposure induces caspase 9 activation and PARP cleavage. However, the addition of Z-Val-Ala-Asp-fluoromethylketone (a general caspase inhibitor) or Z-Leu-Glu(OMe)-His-Asp(OMe)-CH2F (a caspase 9 inhibitor) before CA4P treatment did not block cell death. No change in bcl-2 or bax protein expression was observed. Exposure of WSU-CLL cells to 4 and 5 nM CA4P was associated with overproduction of total p53 and no dramatic change in MDM2, 14-3-3sigma, GADD45, the cyclin-dependent kinase cdc2, its inhibitory phosphorylation, the cdc2-inhibitory kinase (wee1), chk1, or cdc25 hyperphosphorylation. The overaccumulation of p21 and cyclin B1 protein was obvious at 24 h. Furthermore, CA4P treatment showed an increase in the expression of a marker of mitosis (mitotic protein monoclonal-2 antibody) and an overaccumulation of the cyclin B in the nucleus. Our findings suggest that CA4P induces mitotic catastrophe and arrest of WSU-CLL cells mostly in the M phase independent of p53 and independent of chk1 and cdc2 phosphorylation pathways. Apoptosis is a secondary mechanism of death in a small proportion of cells through activation of caspase 9 and PARP cleavage. The two mechanisms of cell death, i.e., mitotic catastrophe and apoptosis, are independent of each other in our model. 相似文献