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11.
We report on a male infant with oral, facial, digital, and skeletal anomalies in association with severe psychomotor delay. This may represent a new oral-facial-digital syndrome. © 1994 Wiley-Liss, Inc.  相似文献   
12.
Immunology of HIV infection   总被引:1,自引:0,他引:1  
The goal of finding an effective vaccine against the human immunodeficiency virus (HIV) is hampered by our uncertainty of the mechanism(s) responsible for the pathogenesis as well as the lack of knowledge of protective mechanisms. The effects of HIV on the immune system are myriad and thus the truly significant manifestations of the pathology are difficult to dissociate from those more peripheral. In this article we will initially characterize the natural history of HIV infection which shows a chronic and perhaps inexorable course. The second part will deal with the immune response mounted against this assault and the final section is a discussion of the possible unfavorable consequences of the immune response that humans muster against this agent.  相似文献   
13.
A homozygous 32-bp deletion in the gene encoding CCR5, a major coreceptor for HIV-1, leads to resistance to infection with HIV-1, and heterozygosity for the deletion is associated with delayed disease progression in persons infected with HIV-1. We investigated the effect of CCR5 heterozygosity on disease progression as measured by both CD4+ T-cell count decline and the occurrence of clinical AIDS symptoms. Using a unified statistical model for CD4 count progression and AIDS development, we examined whether the effect of CCR5 heterozygosity on clinical AIDS is direct or indirect through its effect on CD4 counts. Based on data from the Multicenter AIDS Cohort Study, we noted a protective effect of CCR5 heterozygosity on both CD4 cell count progression and on AIDS occurrence. Furthermore, we found that this protective effect on the occurrence of AIDS was completely mediated through an effect on the CD4 marker. Additional adjustment for the effect of an initial viral load measurement indicate that CCR5 heterozygosity did not have predictive value for either CD4 progression or the development of AIDS beyond its association with early viral load.  相似文献   
14.
Diazepam-dependent cats were challenged with different benzodiazepine recognition site ligands 24 h after the last dose of chronic treatment with diazepam (7 mg/kg, i.p. at 08.00 and 20.00 h, for 21 consecutive days). The benzodiazepine derivatives Ro 15-4513 (a partial inverse agonist) and Ro 15-1788 (a pure antagonist), precipitated an abstinence syndrome within minutes after i.p. administration. Abstinence signs included tremors, increased muscle tone, irritability, fear, pupillary dilation and vocalizations. On the contrary, the beta-carboline derivatives ZK 93426 (an antagonist) and FG 7142 (a partial inverse agonist) failed to precipitate abstinence signs in diazepam-dependent cats when given at doses that prevented the acute effects of diazepam. Our results demonstrate that the ability to induce withdrawal signs in diazepam-dependent cats strongly depends on the benzodiazepine structure of the challenge drug since beta-carboline antagonist and partial inverse agonists lack this property.  相似文献   
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Succinylcholine, a depolarizing muscle relaxant with both activating and desensitizing effects, is used to facilitate endotracheal intubation. The activating effects were found to be above-normal on induction of anesthesia in 7 neurological patients: generalized muscle spasm in 1 myotonic patient, contractures or prolonged contractions in "anatomically" denervated muscles (1 patient), in "functionally" denervated muscles (1 patient) and in "centrally" denervated muscles (4 patients). One of these four presented hyperkalemia and cardiocirculatory collapse. It is important to differentiate these anomalous responses to succinylcholine from those occurring as early signs of rhabdomyolysis or malignant hyperthermia.  相似文献   
18.
Grapefruit juice changes the pharmacokinetic parameters of a variety of drugs metabolized primarily by cytochrome P450 3A. In a three-phase crossover study, six male beagle dogs were administered 100 ml of water (control), 100 ml of commercial liquid grapefruit juice, or 10 g of freeze-dried grapefruit juice (equivalent to 100 ml of liquid grapefruit juice) with 100 ml of water, followed after 2 h by single oral dose of praziquantel (30 mg kg(-1)). After treatment, the dogs were sampled at different times. Determination of praziquantel and its metabolite 4'-hydroxy praziquantel (identified by GC/MS) was performed by HPLC. Liquid and freeze-dried grapefruit juice preadministration increased the C(max) of praziquantel about three-fold and the AUC 2.5- and 2.3-fold, respectively. The T(max) (0.75 h) was unaffected by liquid or freeze-dried grapefruit juice, while T(1/2) was 2.3- and 1.7-fold higher compared with controls. The amount of 4'-hydroxy praziquantel was also affected by both liquid and freeze-dried grapefruit juice administration: the AUC and C(max) increased four- and three-fold, respectively and the T(max) was significantly enhanced. These findings demonstrate that both freeze-dried grapefruit juice and commercial liquid grapefruit juice significantly increase plasma concentrations and T(1/2) of praziquantel in dogs.  相似文献   
19.
Screening with faecal occult blood test (FOBT) has been shown to be effective in reducing mortality from colorectal cancer. Tuscany was the first region in Italy in which a screening programme for colorectal cancer by FOBT was initiated region-wide. The aim of the paper was to describe organizational aspects, a quality control model and the results of this experience. From June 2000 to December 2001, 192583 subjects aged 50-70 were invited to undergo a 1-day immunochemical test without any dietary restriction. A total of 78505 subjects (41%) performed the screening test, of whom 4537 responders had a positive test result (5.8%). Among them, 1122 refused any form of assessment or underwent a colonoscopy outside the screening referral centres, with an overall assessment compliance of 75.3%. Malignancies were found in 193 patients and at least a high-risk adenomatous polyp in 692 patients. In about a quarter of the positive subjects who underwent assessment, cancer or high-risk adenoma was detected. In conclusion, data from this experience supported the feasibility of biennial colorectal screening programme by FOBT, particularly regarding invitation compliance and positivity rate. Further efforts are necessary to implement screening extension and to improve data collection.  相似文献   
20.
We recently identified the direct product of dopamine (DA) by monoamine-oxidase (MAO) activity, dihydroxyphenylacetaldehyde (DOPALD) in the trans-striatal dialysate. Based on these findings, in this work, we directly measured the variations in DOPALD levels after various kinds of pharmacological treatment in rat striatal extracellular fluid. Using both reversible and irreversible MAO inhibitors, we found that MAO-A inhibition suppressed, whereas MAO-B inhibition did not modify DOPALD levels in the dialysate. The vesicular DA uptake blocker Ro 4-1284 led to an increase in extracellular DA and DOPALD, whereas the increase in extracellular DA obtained after administration of the plasma membrane DA uptake blocker GBR-12909 occurred without concomitant changes in DOPALD extracellular levels. Microinfusions of DA through the dialysis probe or systemic administration of L-DOPA increased striatal DOPALD to a greater extent compared with other DA metabolites, both in intact and in 6-hydroxydopamine (6-OHDA)-lesioned striatum. This study indicates that the direct product of MAO activity within the rat striatum derives from the activity of the isoenzyme MAO-A. The assay of DOPALD, together with DOPAC, represents a reliable tool to measure directly, in freely moving animals, DA oxidative metabolism. As recent studies have shown that microinfusions of exogenous DOPALD might induce cell death, pharmacological modulation of DOPALD levels might also be relevant for an understanding of the mechanisms involved in DA neurotoxicity.  相似文献   
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