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排序方式: 共有595条查询结果,搜索用时 15 毫秒
1.
La Rosa Mauricio Omere Chasey Redfern Tiffany Abdelwahab Mahmoud Spencer Nicholas Villarreal Josephine Olson Gayle Saade George R. Saad Antonio F. 《Archives of gynecology and obstetrics》2020,301(1):69-73
Archives of Gynecology and Obstetrics - The objective of this study was to determine if high-dose antibiotic prophylaxis with cefazolin decreases the risk of surgical site infection (SSI) after a... 相似文献
2.
José Roberto Jurado Jorge Hernán Santos Nieto Jairo Ospina Gaitán Constanza Garzón Bonilla Ricardo Villarreal David Acevedo Laura Cabrera Luis Felipe Cabrera Mauricio Pedraza 《Arab Journal Of Gastroenterology》2021,22(2):170-173
Background and study aimsThe COVID-19 outbreak has reorganized surgical team conditions regarding endoscopy. The number of interventions has been reduced, the number of healthcare professionals must be limited, and both the patients and physicians are more protected than ever.Patients and MethodsIn the highest peak of contagion in Colombia, endoscopy, colonoscopy, and esophagogastroduodenoscopy were performed using a low-cost disposable device. A total of 1388 procedures were performed. Every patient was assessed for symptoms via a telephone call, at the health center, and after the procedure, following specific attention routes.ResultsAfter procedure follow-up, no positive cases of COVID-19 were noted.ConclusionThe methodology reduced the risk of infection during the COVID-19 pandemic. 相似文献
3.
Matilde Valencia-Flores David N. Velázquez-Martínez Julían E. Villarreal 《Psychopharmacology》1990,102(1):136-144
The chronic exposure of rats to a schedule of operant water reinforcement coupled with chronically restricted access to water sensitized the animals to intermittentd-amphetamine injections (0.31–2.5 mg/kg with intervals of 12–23 days between any two injections) in such a way that this drug came to produce catastrophic losses of body weight (32.4% of control levels). In the sessions whend-amphetamine was administered, the rats were also given a total of 12 brief electric shocks. Loss of body weight was unaccompanied by parallel changes in operant behavior performance, or in food or water intake. Remarkably, in other studies with the same interventions (sham schedule sessions, water deprivation, and foot shocks), with the exception that reinforcers were never delivered,d-amphetamine did not produce catastrophic falls in body weight. This super-reactivity tod-amphetamine toxicity may be mediated by a possible stressor action of the schedule of reinforcement. Its mechanism might be analogous to the known sensitization produced by classical experimental stressor stimuli to the repeated administration ofd-amphetamine. 相似文献
4.
Long-term persistent vesicular stomatitis virus and rabies virus infection of cells in vitro. 总被引:25,自引:0,他引:25
J J Holland L P Villarreal R M Welsh M B Oldstone D Kohne R Lazzarini E Scolnick 《The Journal of general virology》1976,33(2):193-211
BHK 21 carrier cells persistently infected with VSV Indiana for over 2 years have been shedding generally very low levels of mature infectious virus or mature T particles (averaging less than one-hundredth p.f.u./cell/day) yet most cells are producing virus antigens and are resistant to homologous superinfection. However, large amounts of biologically active T particle RNP can be recovered from cytoplasmic extracts of these carrier cells even at times when they are shedding no detectable infectious virus. This recovered cytoplasmic RNP replicates (with helper B virions) to produce mature T particles, interferes strongly after DEAE dextran-facilitated uptake and, together with B virions, allows the establishment of a persistent carrier state in exposed cells. No 'provirus' DNA copies of the VSV RNA genome are detectable (less than 1/40 copy/cell or I copy per 40 cells) in carrier cells after more than 2 years of persistent infection, and all transfection attempts have failed using DNA from these VSV carriers or DNA from carrier cells persistently infected with some other negative strand RNA viruses (measles, mumps, LCM, influenza, rabies). Infectious viruses shed after more than I year from carrier cells originally infected with wild-type B virions are small plaque mutants showing a slight temperature sensitivity. Cured cell populations can be obtained from the long term VSV carrier culture by cloning in the presence or absence of antiviral antibody. 相似文献
5.
RNA synthesis in BHK 21 cells persistently infected with vesicular stomatitis virus and rabies virus. 总被引:3,自引:0,他引:3
Virus-induced RNA synthesis was studied in BHK 21 cells persistently infected with vesicular stomatitis virus (VSV) and rabies virus by labelling RNA synthesized in the presence of antinomycin D. During persistent infection the species of messenger RNA synthesized were similar in size and relative proportions to those seen during acute infection, but there were some minor differences. Full-sized B virion RNA was generally not detected during persistent infection, and new species (probably DI virion RNA) appeared. 相似文献
6.
Tumor necrosis factor receptor II (TNFRII) exon 6 polymorphism in systemic lupus erythematosus 总被引:4,自引:0,他引:4
Systemic lupus erythematosus (SLE) is a complex autoimmune disease that exhibits extensive clinical heterogeneity. Several studies have suggested a role for tumor necrosis factor alpha (TNFalpha) in SLE and recently, the locus encompassing the TNF receptor II (TNFRII), which is a mediator of TNF effect, was amongst the candidate loci suggested by genetic linkage studies of multi-case SLE families. Komata et al. reported an association between a polymorphism at position 196 (R allele) of TNFR II and SLE in Japanese patients. We have typed SLE patients from two different ethnic populations, Spanish and UK Caucasoids, for this polymorphism using a polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP)-based technique. No significant differences in allele or genotype frequencies were found between cases and matched controls in either population. The TNFRII 196R allele does not appear to be associated with SLE susceptibility in either Spanish or UK populations. 相似文献
7.
Occupational asthma caused by fish inhalation 总被引:1,自引:1,他引:1
J. Rodríguez M. Reaño R. Vives G. Canto P. Daroca J. F. Crespo C. Vila O. Villarreal Z. Bensabat 《Allergy》1997,52(8):866-869
Occupational asthma (OA) due to fish inhalation, confirmed by specific bronchial challenge (SBC), has not been described as yet in medical literature, as far as we know. We describe two patients whose asthma was induced by occupational exposure to fish and confirmed by serial measurements of PEFR and SBC. Two fish-processing workers reported asthma symptoms related to their workplace. They were skin tested with fish extracts and their sera assayed for IgE antibodies to various fish species. Nonspecific bronchial reactivity was assessed by methacholine challenge. The occupational relationship was confirmed by PEFR monitoring in working and off-work periods. SBC with fish extracts was carried out to confirm the diagnosis of OA. Skin tests with raw and cooked plaice, salmon, hake, and tuna in patient 1 and anchovy, sardine, trout, salmon, Atlantic pomfret, and sole in patient 2 were positive. Specific IgE serum antibodies were found to salmon in patient 1 and to trout, anchovy, and salmon in patient 2. PEFR measurements differed significantly (P<0.001) between work and off-work periods for both patients. A bronchial challenge with methacholine was positive in patient 1. SBC with raw hake, salmon, plaice, and tuna extracts in patient 1 and raw salmon extract in patient 2 were all positive with an immediate response. SBC with Dermatophagoides pteronyssinus extract was entirely negative in both patients. In three asthmatic, non-fish-allergic controls, SBC with tuna, hake, salmon, and plaice were all negative. These results suggest that fish inhalation can elicit IgE-mediated occupational asthma. 相似文献
8.
Factors affecting the detection of enteroviruses in cerebrospinal fluid with coxsackievirus B3 and poliovirus 1 cDNA probes. 总被引:4,自引:6,他引:4 下载免费PDF全文
H A Rotbart M J Levin L P Villarreal S M Tracy B L Semler E Wimmer 《Journal of clinical microbiology》1985,22(2):220-224
Enteroviruses are common pathogens of meningitis and encephalitis, and infections are often difficult to distinguish clinically from bacterial and herpetic infections of the central nervous system. An array of enteroviruses added to cerebrospinal fluid in reconstruction experiments were detected by a dot hybridization assay. Optimal handling and processing conditions for infected cerebrospinal fluid were established, and the effect on the hybridization reaction of humoral and cellular components of the inflammatory response was determined. Six hybridization probes, derived from poliovirus 1 and coxsackievirus B3, were then tested, singly and in combinations, to optimize the sensitivity and spectrum of the assay. Implications for enteroviral taxonomy based on these experiments are discussed. 相似文献
9.
A functional hippocampus is required for trace fear conditioning, which involves learning the association of a tone and shock that are separated over time. Young and aged rats received 10 trace conditioning trials. Twenty-four hours later, rats were tested for fear to the tone in a novel chamber by measuring freezing. The results showed significantly lower levels of freezing in aged rats as compared with young rats, which provides evidence of age-related memory impairments. Pseudorandom conditioning groups showed low levels of freezing, indicative of no associative memory. Age-related memory deficits were not found with delay conditioning, which suggests no age-related sensory-motor deficits. These data suggest that aging hinders the ability of the hippocampus to process information separated over time. 相似文献
10.
Evaluation of the efficacy, safety and physiological effects of fluvoxamine in social phobia 总被引:1,自引:0,他引:1
DeVane CL Ware MR Emmanuel NP Brawman-Mintzer O Morton WA Villarreal G Lydiard RB 《International clinical psychopharmacology》1999,14(6):345-351
There is no US Food and Drug Administration (FDA) approved treatment for social phobia although data suggest efficacy for several drug classes, including beta-blockers, benzodiazepines, monoamine oxidase inhibitors, and selective serotonin reuptake inhibitors (SSRIs). The SSRIs are particularly attractive due to their favourable tolerance and safety profile. An open label trial of fluvoxamine was conducted to evaluate its efficacy and safety in the treatment of social phobia (DSM-III-R) and to assess physiological changes that may accompany treatment. Fifteen non-depressed patients, aged 22-44 years (mean 31.6 years), entered the study. A 5-min performance task (public speaking simulation) preceded and concluded the active treatment period. Cardiovascular monitoring was performed during this time and blood sampled for plasma cortisol and steady-state plasma fluvoxamine concentration (at week 7). Ten patients (5 men and 5 women) completed an active 6 week treatment period of flexible dosing (50-150 mg/day). Five patients failed to complete the study due to drowsiness (n = 2), nausea (n = 1), or were lost to follow-up (n = 2). Analysis of clinical ratings indicated a statistically significant decrease in all scales from baseline to week 7 at the conclusion of the active treatment period. Clinical benefits were still evident at follow-up 1 week after drug discontinuation. Neither physiological effects nor plasma drug concentration correlated with clinical change. Fluvoxamine appeared to be effective and well tolerated in completers. Randomized clinical trials are needed to further demonstrate the efficacy of fluvoxamine in the treatment of social phobia. 相似文献