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排序方式: 共有5135条查询结果,搜索用时 15 毫秒
1.
Abdelhadi Lahoum Nasserdine Sabaou Christian Bijani Noureddine Bouras Frédéric Pont Selma P. Snini Florence Mathieu 《Saudi Pharmaceutical Journal》2019,27(1):56-65
The actinobacterium strain ABH26 closely related to Saccharothrix xinjiangensis, isolated from an Algerian Saharan soil sample, exhibited highly antagonist activity against Gram-positive bacteria, yeasts and filamentous fungi. Its ability to produce antimicrobial compounds was investigated using several solid culture media. The highest antimicrobial activity was obtained on Bennett medium. The antibiotics secreted by strain ABH26 on Bennett medium were extracted by methanol and purified by reverse-phase HPLC using a C18 column. The chemical structures of the compounds were determined after spectroscopic (1H NMR, 13C NMR, 1H-1H COSY and 1H-13C HMBC spectra), and spectrometric (mass spectrum) analyses. Two new cyanogriside antibiotics named cyanogriside I (1) and cyanogriside J (2), were characterized along with three known caerulomycins, caerulomycin A (3), caerulomycin F (4) and caerulomycinonitrile (5). This is the first report of cyanogrisides and caerulomycins production by a member of the Saccharothrix genus. The minimum inhibitory concentrations (MIC) of these antibiotics were determined against pathogenic microorganisms. 相似文献
2.
Dino Donataccio Francine Roggen Chantal De Reyck Catherine Verbaandert Monique Bodeus Jan Lerut 《Transplant international》2006,19(1):38-43
The use of livers from anti-hepatitis B core (HBc) positive donors can alleviate donor shortage. Nineteen of 367 (6%) adults receiving anti-HBc positive allografts [three were hepatitis B antigen (HBsAg) negative, hepatitis B antibody (HBsAb) positive; four were HBsAg positive and 12 were not exposed to hepatitis B viral (HBV) infection] were retrospectively reviewed. In HBsAg negative recipients, immunoprophylaxis (IP) was guided by viral serology and immunohistochemistry (IH) of day 0 and day 7 liver biopsies. If IH was negative, IP was stopped. None of three HBsAg negative, HBsAb positive recipients infected; one (replicating) of four HBsAg positive recipients reinfected and seven of eight (87.5%) HBsAg, HBsAb negative recipients, who did not receive long-term IP, infected after a median time of 2 years (range 1-5); one patient died of liver failure. Four HBsAg, HBsAb negative recipients, receiving life-long IP, remained infection free. Anti-HBc positive donor livers must be directed selectively first to HBsAg positive recipients, next to recipients having HBV antibodies and finally to HBV-naive recipients. Identification of both donor and recipient risk factors for HBV infection before transplantation allows indiscriminate use of antiviral prophylaxis. The necessity for IP therapy should be guided by HBV-DNA testing of donor liver tissue and serum. IH of early liver biopsies is an unreliable marker for predicting antiviral treatment requirements. 相似文献
3.
O P Jakobsson B Pontén 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》1990,24(2):149-155
The details of two consecutive groups of cleft palate patients treated with one- or two-stage palate repair are presented. The total number of patients is 237, with 128 operated in one stage, and 109 operated in two stages. In the two-stage group, the frequency of 'unintended' palatal fistulas decreased by 80%, and the use of blood transfusions was greatly reduced, but total operation time and hospital stay were longer. The results in terms of speech quality, facial growth and dental occlusion, will be reported on separately. 相似文献
4.
OBJECTIVE: Much effort has been devoted to the search for the neurophysiological correlates of implicit memory. A commonly held view is that the early portion (250-500 ms) of the event-related potential (ERP) word repetition effect reflects processes important for perceptual implicit memory whereas the latter portion reflects processes implicated in explicit memory. It is, however, difficult to disentangle with certainty the relative contributions of each form of memory on ERPs since both forms co-exist in normal subjects. To dissociate ERP effect related to implicit and explicit memory, we used isoflurane sedation in normal subjects to suppress explicit remembering while sparing implicit memory. These ERPs were compared with those of non-medicated control subjects. METHODS: Thirteen subjects performed an incidental encoding task for words presented auditorily during the inhalation of a subanesthetic dose of isoflurane. After termination of isoflurane administration, we assessed free recall and recorded ERPs during a syllable completion task (implicit memory) and during a passive listening task (ERP repetition effect). Eleven non-medicated control subjects were tested in a similar manner. RESULTS: The controls showed robust early and late ERP repetition effect. The isoflurane group had implicit memory without free recall and showed no ERP repetition effect. CONCLUSIONS: These findings failed to show an association between any part of the repetition effect and perceptual implicit memory. The results are consistent with the view that processes linked to explicit memory contribute to the ERP repetition effect since there was a marked difference in free recall between the control and isoflurane groups. SIGNIFICANCE: The present study shows that the reversible alterations of memory by general anesthetics can be used to study the neurophysiological correlates of memory processes. 相似文献
5.
Philippe Brun Heykel Kchouk Brigitte Mouchet Véronique Baudouin Alain Raynaud Chantal Loirat Annabelle Azancot-Benisty 《Pediatric nephrology (Berlin, Germany)》1997,11(1):27-30
To evaluate the reliability of Doppler ultrasonography (US) in identifying children with renal artery stenosis (RAS) among
those with hypertension, we compared Doppler US results in 22 hypertensive children (mean age 8.9±4.3 years), with (13 cases)
and without RAS at angiography, and in 33 normotensive children (mean age 8.8±4.7 years). We observed 2 false-negatives and
2 false-positives with Doppler US. Of the 2 false-negative diagnoses, 1 had RAS on an accessory renal artery located behind
a normal upper polar artery and the other was observed in a patient with bilateral multiple stenosis of the very distal segments
of renal arteries. The 2 false-positive diagnoses were due to sinuous left renal artery and to technical reasons, respectively.
In another patient, Doppler US showed a tight RAS, while arteriography was normal. RAS was subsequently confirmed by a second
arteriography. Peak systolic velocity values of Doppler US were significantly higher in patients with proven angiographic
RAS (3.44±0.66 m/s) than in hypertensive patients with normal renal arteries at angiography (0.99±0.35 m/s, P <0.0001) and normotensive healthy children (1.04±0.23 m/s, P <0.0001). With the use of multiple views, and the experience acquired with practice, false-negatives or false-positives due
to the geometry of the renal artery can be avoided. Nevertheless, very distal stenosis can be missed by Doppler US.
Received October 30, 1995; received in revised form April 16, 1996; accepted May 14, 1996 相似文献
6.
H O Adami B Glimelius P Sparén L Holmberg U B Krusemo J Pontén 《Acta oncologica (Stockholm, Sweden)》1992,31(1):1-10
The temporal changes in childhood and adolescent cancer survival in Sweden 1960-1984 were analyzed. Complete follow-up through 1986 of 6,262 patients younger than 20 years at diagnosis revealed that the overall 5-year survival rates increased from 36.1 to 65.7% in males and from 43.6 to 73.6% in females. The temporal trends differed markedly between age groups and tumour sites and types. Over the study period, 5-years, survival for testicular cancer increased from 46.9 to 87.2%, kidney cancer, predominantly Wilms' tumour from 35.5 to 77.1% (with a higher rate of 89.1% in 1975-1979), Hodgkin's disease from 61.2 to 91.9%, non-Hodgkin's lymphoma from 32.5 to 76.6%, and all leukemias from 8.9 to 58.7%. Only a moderate improvement was noted for tumours of the bone, muscle and connective tissue, and survival rates for tumours of the nervous system remained largely unchanged. Our data reflect the remarkable therapeutic improvements that have occurred for cancer in the young and indicate that these improvements have rapidly become available in Sweden. 相似文献
7.
Véronique Strijckmans Michel Bottlaender Humin Luo Michèle Ottavianil Daniel W. McPherson Christian Loc'h Chantal Fuseau Furn F. Knapp Bernard Mazière 《European journal of nuclear medicine and molecular imaging》1997,24(5):475-482
We studied the potential of three radiobrominated isomers of BrQNP, (Z(-,-)-[76Br]BrQNP,E(-,-)-[76Br]BrQNP andE(-,+)-[76Br]BrQNP), as suitable radioligands for imaging of central muscarinic cholinergic receptors in the human brain. These radioligands were stereospecifically prepared by electrophilic radiobromodestannylation of the respective tributylstannyl precursors using no-carrier-added [76Br]BrNH4 and peracetic acid. Preliminary pharmacological characterizations were determined by biodistribution, autoradiography, competition, displacement and metabolite studies in rats. The (-,-)-configuration presented important specific uptakes in brain muscarinic cholinergic receptor (mAChR)-rich structures and in heart, low metabolization rates and an apparent M2 selectivity. The (-,+)-configuration revealed more rapid clearance, lower uptake, a higher metabolization rate and an apparent M1 selectivity. Reversibility of the binding was confirmed for the three radiotracers. Positron emission tomography in the living baboon brain revealed high and rapid uptake in the brain and accumulation in the mAChR-rich structures studied. At 30 min p.i., theE(-,-)-radiotracer reached a plateau in cortex, pons and thalamus with concentrations of 29%, 24% and 19% ID/l, respectively.Z(-,-)-[76Br]BrQNP also accumulated in these structures, reaching a maximal uptake (27% ID/l) in the cortex 2 h p.i. At 5 min p.i. a plateau (17% ID/l) was only observed in the cortex for theE(-,+)-[76Br]BrQNP; by contrast, the other structures showed slow washout. After 3 weeks, the (-,-)-radiotracers were studied in the same baboon pretreated with dexetimide (1 mg/kg), a well-known muscarinic antagonist. In all the mAChR structures, the highly reduced uptake observed after this preloading step indicates that these radiotracers specifically bind to muscarinic receptors.Z(-,-)-[76Br]BrQNP, which is displaced in higher amounts from M2 mAChR-enriched structures, reveals an M2 affinity. The two isomers having the (-,-)-configuration are potential probes for investigating central muscarinic receptors. The absolute configuration on the acetate chiral centre influences their muscarinic subtype selectivity and thecis-trans isomerism of the vinyl moiety affects their specific fixation. 相似文献
8.
9.
Antidepressant-induced switching is a major risk during the treatment of bipolar depression. Despite several clinical studies, questions remain regarding both the definition of these mood switches and the most appropriate therapeutic strategy to avoid this adverse effect.This review will first briefly consider the current guidelines for the acute treatment of bipolar depression. We will then review the mechanisms of action of antidepressant and mood stabilisers, and the switches induced by various types of antidepressant treatments, or triggered by antidepressant withdrawal, as well as by atypical antipsychotics. We then will address the risk of mood switch according to the type of mood stabiliser used. The propensity to mood switches in bipolar patients is subject to individual differences. Therefore we will describe both the clinical and biological characteristics of patients prone to mood switches under antidepressant treatment. However, the clinical characteristics of the depressive syndrome may also be a key determinant for mood switches. Various data help identify the most appropriate drug management strategies for avoiding mood switches during the treatment of bipolar depression. Selective serotonin reuptake inhibitors appear to be the drugs of first-choice because of the low associated risk of mood switching. Antidepressants must be associated with a mood stabiliser and the most effective in the prevention of switches seems to be lithium. Whatever the mood stabiliser used, effective plasma levels must be ensured. The optimal duration of antidepressant treatment for bipolar depression is still an open issue - prolonged treatments after recovery may be unnecessary and may facilitate mood elation. Moreover, some mood episodes with mixed symptoms can be worsened by antidepressants pointing to the need for a better delineation of the categories of symptoms requiring antidepressant treatment. Finally, as a result of this review, we suggest some propositions to define drug-induced switches in bipolar patients, and to try to delineate which strategies should be recommended in clinical practice to reduce as far as possible the risk of mood switch during the treatment of bipolar depression. 相似文献
10.
Susceptibilities to antimicrobial agents, bacteriophage lysis patterns and enzymatic polymorphism analysis were used to study genetic variability in Escherichia coli in order to study the relationship between clinical and environmental isolates of the species. Enzymatic polymorphism analysis proved the most useful. The findings were complemented by numerical analysis of phage typing and antimicrobial susceptibilities. 相似文献