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101.
3-Hydroxypropyl flufenamide (Flu-HPA) is one of a series of flufenamic acid derivatives that enhances blood clot lysis in vitro. Studies of possible mechanisms of action of Flu-HPA were undertaken. The profibrinolytic activity of Flu-HPA in clot lysis assays was found to be dependent on plasminogen. The influence of Flu-HPA on the ability of purified alpha 2-antiplasmin to inhibit purified plasmin was studied. Plasmin activity was determined using 125I-fibrin plates or the spectrophotometric tripeptide substrate, Val-Leu-Lys-paranitroanilide. At Flu-HPA concentrations greater than 1 mM, the inhibitory activity of alpha 2-antiplasmin was abolished in a time-dependent and concentration- dependent manner. The influence of Flu-HPA on the ability of purified Cl inhibitor to inhibit purified plasma kallikrein and beta-Factor XIIa was also studied. Cl inhibitor activity was abolished by Flu-HPA at concentrations greater than 2 mM. Notably, Flu-HPA up to 60 mM did not affect the amidolytic activities of plasmin, kallikrein, or beta-Factor XIIa. Flu-HPA did not release enzyme activity from preformed complexes of either alpha 2-antiplasmin and plasmin of Cl inhibitor and kallikrein. A water-soluble derivative of flufenamic acid, N-flufenamyl- glutamic acid, also inactivated alpha 2-antiplasm and Cl inhibitor. This inactivation was shown to be reversible. These results indicate that synthetic fibrinolytic compounds such as flufenamic acid derivatives may promote fibrinolysis by directly inactivating alpha 2- antiplasmin and Cl inhibitor. 相似文献
102.
Nodular mixed lymphoma: results of a randomized trial failing to confirm prolonged disease-free survival with COPP chemotherapy 总被引:2,自引:0,他引:2
Fifty-two patients with stage III or IV nodular mixed lymphocytic- histiocytic lymphoma (NM) were entered on a prospective randomized trial comparing cyclophosphamide-prednisone (CP) to either COPP (cyclophosphamide, vincristine, procarbazine, prednisone) or BCVP (BCNU, cyclophosphamide, vincristine, prednisone). The COPP regimen utilized in this Eastern Cooperative Oncology Group (ECOG) trial was similar to the four-drug regimen C-MOPP reported by the National Cancer Institute to achieve prolonged relapse-free survival in this histology. No significant differences in complete response rates, response duration, or overall survival were noted among the three regimens. A pattern of continuous late relapse was observed for all three chemotherapy programs. Although 11 of the 18 (61%) COPP patients achieved a complete response, only 3/11 (27%) remain disease-free with a median follow-up of over 3 yr. However, two of these three long-term complete responders have died with no clinical evidence of recurrent disease. The COPP patients received 84% of the calculated ideal doses of cyclophosphamide and 78% of the ideal dosage of procarbazine. Grade 3-4 hematologic toxicity was noted in 22% of the COPP group, 36% with BCVP, and 0% for the CP patients. We were unable to confirm the ability of COPP to achieve durable complete remissions in NM lymphoma. The cyclophosphamide-prednisone combination was equally effective when compared with COPP and BCVP, but produced minimal toxicity. 相似文献
103.
Vasoactive intestinal polypeptidergic nerves and Brunner's gland secretion in the rat 总被引:1,自引:0,他引:1
P Kirkegaard J M Lundberg S S Poulsen P S Olsen J Fahrenkrug T H?kfelt J Christiansen 《Gastroenterology》1981,81(5):872-878
Vasoactive intestinal polypeptide is known to have powerful effect on the secretions from endocrine and exocrine glands. By immunohistochemical studies on the rat, both a dense network of vasoactive intestinal polypeptide-immunoreactive nerve fibers around the acini of Brunner's glands, and small ganglia with vasoactive intestinal polypeptide-immunoreactive nerve-cell bodies close to the glands were demonstrated. Intravenous infusions of vasoactive intestinal polypeptide in doses of 10, 100, and 1000 ng/kg.h significantly increased flow rate, as well as bicarbonate and protein output from Brunner's glands in the rat. After infusion of vasoactive intestinal polypeptide the secretory cells, which in the control group were rich in PAS-positive mucin, became almost completely PAS-negative. It is suggested that physiologic secretion from Brunner's glands may be stimulated by the vasoactive intestinal polypeptidergic nerves. 相似文献
104.
Blood-brain barrier permeability in galactosamine-induced hepatic encephalopathy. No evidence for increased GABA-transport 总被引:1,自引:0,他引:1
Blood-brain barrier permeability to the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), to sucrose and to sodium was studied in rats with galactosamine-induced liver damage and hepatic encephalopathy by means of an arterial integral uptake technique. Permeability to GABA was unaltered in all examined brain regions (2.47 +/- 0.25.10(-5) cm3.s-1.g-1, mean +/- S.D.) as compared to control rats (2.49 +/- 0.19.10(-5) cm3.s-1.g-1). The permeability to sucrose (galactosamine 0.25 +/- 0.02 vs. controls 0.24 +/- 0.02.10(-5) cm3.s-1.g-1) and to sodium (galactosamine 5.33 +/- 0.04 vs. controls 5.40 +/- 0.05.10(-5) cm3.s-1.g-1) was also unchanged in hepatic encephalopathy. At the time of investigation mean liver function measured by antipyrine clearance was reduced from 0.39 in control rats to 0.23 ml/min/100 g body wt. in galactosamine-treated animals. The present study does not support the suggestion that peripheral GABA penetrates the blood-brain barrier to any higher extent in hepatic encephalopathy. This provides evidence against at least part of the GABA-hypothesis. Furthermore, an unspecific increased blood-brain barrier permeability in hepatic encephalopathy, as measured by sucrose and sodium uptake, was not found. It is concluded that the GABA-theory requires further careful reevaluation. 相似文献
105.
KH Neppelenbroek RS Seó VM Urban S Silva LN Dovigo JH Jorge NH Campanha 《Oral diseases》2014,20(4):329-344
In healthy individuals, Candida species are considered commensal yeasts of the oral cavity. However, these microorganisms can also act as opportunist pathogens, particularly the so‐called non‐albicans Candida species that are increasingly recognized as important agents of human infection. Several surveys have documented increased rates of C. glabrata, C. tropicalis, C. guilliermondii, C. dubliniensis, C. parapsilosis, and C. krusei in local and systemic fungal infections. Some of these species are resistant to antifungal agents. Consequently, rapid and correct identification of species can play an important role in the management of candidiasis. Conventional methods for identification of Candida species are based on morphological and physiological attributes. However, accurate identification of all isolates from clinical samples is often complex and time‐consuming. Hence, several manual and automated rapid commercial systems for identifying these organisms have been developed, some of which may have significant sensitivity issues. To overcome these limitations, newer molecular typing techniques have been developed that allow accurate and rapid identification of Candida species. This study reviewed the current state of identification methods for yeasts, particularly Candida species. 相似文献
106.
107.
Togsverd-Bo K Lerche CM Philipsen PA Poulsen T Wulf HC Haedersdal M 《Experimental dermatology》2012,21(4):260-264
Topical photodynamic therapy (PDT) with methyl-aminolevulinate (MAL) is a well-established treatment for precancerous skin lesions and non-melanoma skin cancer. Treatment outcomes are less effective for thick than for superficial lesions, which are presumed to be due to insufficient PpIX biodistribution in tumour tissue. Hexyl-aminolevulinate (HAL) is a more lipophilic photosensitizer precursor than MAL and may penetrate the skin to a greater depth and more homogeneously. We compared HAL- and MAL-induced PpIX accumulation in specific skin compartments using concentrations of 2%, 6% and 20% HAL and MAL on long-term UV-irradiated mouse skin. Furthermore, 20% HAL and 20% MAL were applied to non-irradiated skin. Porphyrin fluorescence was measured by fluorescence microscopy in selected skin regions: the epidermis, superficial dermis, deep dermis and sebaceous gland epithelium down to a depth of 1 mm. We found higher PpIX fluorescence intensities in epidermis and sebaceous gland epithelium from 2%, 6% and 20% HAL (median 72-104 au) than in corresponding concentrations of MAL (median 35-69 au) (P < 0.01). Fluorescence intensities in the superficial (35 au) and deep dermis (32 au) were similar for HAL and MAL (P = 0.51) and lower than epidermal fluorescence intensities (P < 0.001). Significantly, higher median PpIX fluorescence intensities (64 au) were found in 20% MAL-incubated skin irradiated with UV than in non-irradiated skin (48 au) (P < 0.001). HAL-induced fluorescence intensities did not depend on UV exposure (HAL 20%, UV: 72 au, non-UV: 70 au) (P = 0.87). In conclusion, HAL express high affinity for epidermis and sebaceous gland epithelium, and MAL for actinically damaged skin, which raises future perspectives for improved selectivity in PDT. 相似文献
108.
109.
Diagnosis of the thoracic outlet syndrome is often difficult, particularly in patients without osseous abnormalities on plain radiographs. The radiographic and computed tomographic (CT) findings were reviewed from 27 patients with thoracic outlet syndrome and 21 normal subjects. The plain radiographs and CT scans were assessed by two independent observers without awareness of the clinical history. Fifteen patients with thoracic outlet syndrome had osseous abnormalities (anomalous cervical ribs; abnormally long, drooping C-7 transverse processes) identifiable on plain radiographs. CT did not provide further diagnostic information in the patients with abnormal radiographs. Eight of 12 patients (66%) with normal plain radiographs had abnormal findings on CT scans, consisting of impingement of the C-7 transverse process on the scalene triangle or anteromedial aspect of the middle scalene muscle. Only two of 21 control patients (9.5%) displayed this CT abnormality (P less than .01). CT may be useful in patients with symptoms suggestive of thoracic outlet syndrome and no osseous abnormalities on plain radiographs. 相似文献
110.