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A Dávalos

Publications and source records attributed to A Dávalos.

16 recordsLinked to original sources
PubMed1992

[Idiopathic icepick-like headache].

Two cases of idiopathic icepick-like headache are presented. This entity is clinically well defined but the appearance of accesses of intense, extremely brief pain commonly located at the same point in the territory of the first trigeminal branch followed at variable intervals and responding almost exclusively to treatment with indomethacin is little known. The appearance of pain crisis at regular intervals in one case lead to the differential diagnosis of cluster headache of a habitually different treatment: correct diagnosis requires a detailed account of the clinical characteristics of the pain with special emphasis on chronopathology.

Adult↗
PubMed1991

Novel organization of the common nodulation genes in Rhizobium leguminosarum bv. phaseoli strains.

Nodulation by Rhizobium, Bradyrhizobium, and Azorhizobium species in the roots of legumes and nonlegumes requires the proper expression of plant genes and of both common and specific bacterial nodulation genes. The common nodABC genes form an operon or are physically mapped together in all species studied thus far. Rhizobium leguminosarum bv. phaseoli strains are classified in two groups. The type I group has reiterated nifHDK genes and a narrow host range of nodulation. The type II group has a single copy of the nifHDK genes and a wide host range of nodulation. We have found by genetic and nucleotide sequence analysis that in type I strain CE-3, the functional common nodA gene is separated from the nodBC genes by 20 kb and thus is transcriptionally separated from the latter genes. This novel organization could be the result of a complex rearrangement, as we found zones of identity between the two separated nodA and nodBC regions. Moreover, this novel organization of the common nodABC genes seems to be a general characteristic of R. leguminosarum bv. phaseoli type I strains. Despite the separation, the coordination of the expression of these genes seems not to be altered.

Acyltransferases↗
PubMed1990

Deteriorating ischemic stroke: risk factors and prognosis.

To determine a risk profile of deterioration in cerebral infarction of less than 8 hours' duration, we studied prospectively a series of clinical and radiologic data in 98 patients. We evaluated the Canadian Neurological Scale Score and Barthel index during a follow-up period of 3 months. There was deterioration in the 1st 48 hours in 40.8% of the patients. High systolic blood pressure, elevated blood sugar concentration at admission, and carotid territory involvement were independently related with deterioration in the logistic regression analysis. Death occurred in 35% of the patients with deteriorating infarcts and in 8.6% of those with stable infarcts. At the end of the study, functional capacity was lower in those with deteriorating infarcts, but the 2 groups improved in parallel from the 4th day onward.

Blood Glucose↗
PubMed1989

Characterization of Rhizobium phaseoli Sym plasmid regions involved in nodule morphogenesis and host-range specificity.

Two nodulation regions from the symbiotic plasmid (pSym) of Rhizobium phaseoli CE-3 were identified. The two regions were contained in overlapping cosmids pSM927 and pSM991. These cosmids, in a R. phaseoli pSym-cured strain background, induced ineffective nodules on Phaseolus vulgaris roots. Transconjugants of Rhizobium meliloti harbouring pSM991 induced nodule-like structures on bean roots, suggesting that this cosmid contains host-range determinants. Analysis of deletions and insertional mutations in the sequences of pSM991 indicated that the genes responsible for the induction and development of nodules in P. vulgaris are organized in two regions 20 kb apart. One region, located in a 6.8 kb EcoRI fragment, includes the common nodABC genes. The other region, located in a 3.5 kb EcoRI fragment, contains information required for host-range determination.

Blotting, Southern↗
PubMed1989

Epidural morphine analgesia in Guillain Barré syndrome.

Severe pain is a frequent symptom in the Guillain Barré syndrome and can be intense, long lasting and with no response to the usual analgesics, including parenteral opiates. Epidural analgesia using morphine chloride in low doses has satisfactorily relieved pain in this disease in nine patients.

Adult↗
PubMed1988

Computed tomography in reversible ischaemic attacks: clinical and prognostic correlations in a prospective study.

Two hundred and nineteen patients admitted with reversible atherothrombotic ischaemic attacks were prospectively evaluated by computed tomography. Of these patients, 122 were diagnosed as suffering from transient ischaemic attacks, 58 from reversible ischaemic neurological deficits and 39 from reversible ischaemic neurological deficits with incomplete resolution. In 133 cases the ischaemic event affected the carotid system, in 63 the vertebrobasilar system and in 23 cases the system could not be determined. Brain infarctions were observed in 64 patients (29.2%), cerebral atrophy in 96 (44.4%) and dilatation of a ventricle in 17 (7.8%). The frequency of brain infarction was related to the duration of the neurological deficit, being 20.5% in those with transient ischaemic attacks, 37.9% in those with reversible ischaemic neurological deficits and 43.6% in patients with reversible ischaemic neurological deficits with incomplete resolution (P = 0.005). Ischaemic lesions were closely correlated with abnormalities on supra-aortic trunk angiography or Doppler ultrasonography. During an average follow-up period of 21 months, a higher percentage of recurrence was found in those patients with CT infarctions, but the difference was not significant.

Cerebral Infarction↗
PubMed1987

Low-dose acetylsalicylic acid (ASA) plus dipyridamole versus dipyridamole alone in the prevention of stroke in patients with reversible ischemic attacks.

A total of 243 patients who had reversible ischemic attacks (RIA) were submitted to clinical trial to determine whether dipyridamole (400 mg/day) (D) or aspirin (100 mg/48 hours) + dipyridamole (300 mg/day) (ASA + D) would produce significant reduction in the subsequent occurrence of RIA and completed stroke. One hundred and fifteen were selected for Group ASA + D and 71 were treated with dipyridamole only. The treatment groups were similar in relation to age, sex, risk factors, duration and presumed vascular territory of RIA, incidence of alterations of arterial supra-aortic trunks, cerebral infarct (CT scan), and platelet function. Patients were followed for a mean time of 21 months. At the end of the study, 21.7% of the ASA + D group and 19.7% in the D group had suffered new episodes of RIA or completed stroke (p = 0.88). Frequency of stroke (reversible ischemic neurologic deficit or completed stroke) was 7.8% in the ASA + D patients and 9.8% in the D patients (p = 0.83). Subgroup analysis did not show significant differences either. It is concluded that ASA + D has no significantly greater beneficial effect than that observed with D alone in the secondary prevention of atherothrombotic cerebral ischemia. However, a statistical Type II error cannot be excluded by the reduced number of recurrences.

Adult↗
PubMed1986

5-Hydroxytryptophan versus methysergide in the prophylaxis of migraine. Randomized clinical trial.

One hundred and twenty-four migraineurs were treated randomly with 5-hydroxytryptophan (5-HTP) or with methysergide (M). The two groups were homogeneous without significant statistical differences with respect to age, sex, pill use, type of migraine and frequency of attacks before entry. A significant improvement was observed in 75% of the patients treated with M and in 71% of the cases treated with 5-HTP. The most beneficial effect of 5-HTP appears to be felt with regard to the intensity and duration rather than the frequency of the attacks. Side effects were more frequent in the M group than in the 5-HTP group. These results suggest that 5-HTP could be a treatment of choice in the prophylaxis of migraine.

5-Hydroxytryptophan↗