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41.
In this work we analyzed the immunoreactive-methionine-enkephalin (IR-Met-enkephalin) levels in several brain regions of rats sacrificed during the tonic extension, induced by acute treatment with pentylenetetrazol (PTZ). The results show an increase of IR-Met-enkephalin content in striatum but not in amygdala, hypothalamus, septum, hippocampus and cortex. To characterize whether this elevation of enkephalin levels in striatum corresponded to the releasable pool, we studied the intro efflux of this peptide in striatal slices of rats sacrificed during the seizures, in acute PTZ and in PTZ-kindled rats (kindling group I). In addition, PTZ-kindled rats were analyzed 24 h after the last stimulus (kindling group II). The striatal slices of acute group and kindling group I displayed a significant increase in the evoked release of IR-Met-enkephalin. However, no significant changes occurred from striatal slices of kindling group II animals. In vitro superfusion of GABA (100 μM) produced a 63% decrease in IR-Met-enkephalin released from striatal slices in both saline and acute PTZ-treated rats. Several studies suggest that opioid peptides may be released in the ictal phase of seizure in order to mediate some transient postictal behavior. Our results suggest that of several brain regions tested, only the striatal IR-Met-enkephalin may be released during the ictus to mediate postical behavior in the acute PTZ treated and in PTZ-kindled rats. This effect may be regulated by the GABA system.  相似文献   
42.
43.
Bifunctional chelates offer a general approach for the linking of radioactive metal cations to macromolecules. In the specific case of 99mTc, a variety of technologies have been developed for assembling a metal-chelate-biomolecule complex. An evaluation of these methodologies requires an appreciation of the coordination characteristics and preferences of the technetium core structures and oxidation states, which serve as platforms for the development of the imaging agent. Three technologies, namely, the MAG3-based bifunctional chelates, the N-oxysuccinimidylhydrazino-nicotinamide system and the recently described single amino acid chelates for the {Tc(CO)3}1+ core, are discussed in terms of the fundamental coordination chemistry of the technetium core structures. In assessing the advantages and disadvantages of these technologies, we conclude that the single amino acid analogue chelates (SAAC), which are readily conjugated to small peptides by solid-phase synthesis methods and which form robust complexes with the {Tc(CO)3}1+ core, offer an effective alternative to the previously described methods.  相似文献   
44.

Background

HBV DNA quantitation is used extensively world wide for the diagnosis and monitoring of treatment of Hepatitis B virus (HBV) infection. However, it has still to be popular in India. The aim of this study was to quantitate HBV – DNA by Real time – PCR method in Hepatitis B and in immuno-compromised patients, to compare the results with HBeAg detection and to monitor the response to therapy of chronic Hepatitis B patients to antivirals.

Methods

Ninety one serum samples of Hepatitis group of patients (all HBsAg positive), 41 samples from immuno-compromised patients (all HBsAg negative) and 49 patients of Chronic Hepatitis B group (all HBsAg positive) were the subjects of this first ever study in Armed Forces. Twenty serum samples from healthy volunteers and non-hepatitis B patients served as negative controls. The amplification detection was carried out in a Rotor-Gene 2000-sequence detector

Results

Amongst Hepatitis B group, 33% (30/91) of the samples were positive for HBV-DNA and 26% (24/91) of samples were positive for HBeAg. In the immuno-compromised group of patients 14.6% (6/11) of samples were positive for HIV-DNA and 9.7% (4/41) were positive for HBeAg. Of the Chronic Hepatitis B patients on treatment, all (100%) were positive by HBV-DNA, whereas 29/49 (59.2%) were positive by HBeAg before treatment. After treatment with antivirals, 06/49 (12.2%) were positive by both tests and 11/49 (22.5%) were positive only by HBV-DNA. 32/49 (65.3%) patients became negative serologically after therapy.

Conclusion

HBeAg status did not necessarily reflect HBV-DNA level in the serum, as 10/91 (11%) in the Hepatitis B group, 2/41 (4.9%) in the immuno compromised group and 20/49 (40.8%) patients in the Chronic Hepatitis B group were positive for HBV-DNA but negative for HBeAg. HBV-DNA was not found to be positive amongst any of the negative controls. Real time – PCR is a sensitive and reproducible assay for HBV-DNA quantitation and may be started in Armed Forces referral centers in the near future.Key Words: Real time – PCR, Chronic Hepatitis B, HBV – DNA, Antivirals  相似文献   
45.
Computed tomography of abdominal fatty masses   总被引:2,自引:0,他引:2  
  相似文献   
46.
OBJECTIVE: To validate a version of the Food Security Scale (FSS) in communities located in Sierra de Manantlán, Jalisco. MATERIAL AND METHODS: Using focus groups, the FSS was modified to fit the Mexican context. Subsequently, a survey was applied to women with pre-school aged children. The FSS was validated in correlation with a household food inventory and the dietary variety of the individual being interviewed. The interview also included a socioeconomic questionnaire. RESULTS: Forty-four percent of the households reported mild food insecurity, 33% reported moderate hunger and 19.7% reported severe hunger. Food insecurity was significantly and inversely correlated with the number of food items in the household (r=-0.36**), animal source foods (r=-0.28**), dairy products (r=-0.25*), processed foods (r=-0.37**), fruits (r=-0.21*), and vegetables (r=-0.28**); *p<0.05, **p< 0.01. Food insecurity was also associated with low dietary variety (r=-0.23, p=0.02). These associations were maintained in multivariate models. CONCLUSIONS: The FSS is a useful tool for monitoring food insecurity in rural regions of Jalisco.  相似文献   
47.
Several neuroimaging techniques are promising tools as early markers of brain pathology in Alzheimer's disease (AD). On structural MRI, atrophy of the entorhinal cortex is present already in mild cognitive impairment (MCI). In the autosomal dominant forms of AD, the rate of atrophy of medial temporal structures separates affected from control persons even 3 years before the clinical onset of cognitive impairment. The elevated annual rate of brain atrophy offers a surrogate tool for the evaluation of newer therapies using smaller samples, thereby saving time and resources. On functional MRI, activation paradigms activate a larger area of parieto-temporal association cortex in persons at higher risk for AD, whereas the entorhinal cortex activation is lesser in MCI. Similar findings have been detected with activation procedures and water (H(2)(15)O) PET. Regional metabolism in the entorhinal cortex, studied with FDG PET, seems to predict normal elderly who will deteriorate to MCI or AD. SPECT shows decreased regional perfusion in limbic areas, both in MCI and AD, but with a lower likelihood ratio than PET. Newer PET compounds allow for the determination in AD of microglial activation, regional deposition of amyloid and the evaluation of enzymatic activity in the brain of AD patients.  相似文献   
48.

OBJECTIVE:

Inflammation plays an important role in the development of chronic lung disease (CLD), which has become a major cause of morbidity in surviving infants less than 1250 g at birth. The authors hypothesized that the progression of this inflammation and, therefore, the establishment of CLD would be decreased with the use of early prophylactic inhaled corticosteroids. Short, and long term respiratory and neurodevelopmental outcomes were also examined.

DESIGN:

A double-blind, randomized placebo controlled trial.

SETTING:

Level-III neonatal intensive care unit.

POPULATION STUDIED:

Sixty infants less than 1250 g at birth, diagnosed with respiratory distress syndrome and requiring ventilatory support at 72 h of age were enrolled in the study.

INTERVENTION:

Infants enrolled received either placebo or beclomethasone diproprionate by a metered dose inhaler, which was used in-line with the ventilator circuit while the infant was ventilated and then via a spacer until 28 days of age.

RESULTS:

Thirty infants were given beclomethasone and 30 were given placebo. There were two deaths in each group. Among the surviving infants, the frequency of moderate-to-severe CLD was 17% in each study group. Mean time to extubation was not different for beclomethasone compared with placebo at 16.4 and 12.5 days (P=0.12), respectively. The requirement for intravenous corticosteroids was lower in the beclomethasone-treated group (RR 0.67, 95% CI 0.43 to 1.04), although this difference was not statistically significant. The incidence of growth failure, infection and intraventricular hemmorhage did not differ between the two groups. Long term outcomes were not different with respect to the incidence of respiratory re-admissions, cerebral palsy, developmental delay, blindness or deafness.

CONCLUSIONS:

Early treatment with inhaled beclomethasone diproprionate did not reduce the incidence of CLD or decrease the duration of mechanical ventilation. The decrease in intravenous corticosteroid use was not statistically significant. Long term outcome was not affected.  相似文献   
49.
OBJECTIVES: To analyze the incidence and characteristics of benign paroxysmal positional vertigo (BPPV) in patients with Ménière's disease who did not respond to medical treatment and to whom intratympanic gentamycin treatment was proposed. STUDY DESIGN: This is a retrospective analysis of the patients in our database. A complete otoneurologic bedside examination of each patient, including assessment of positional nystagmus, was performed at the time of diagnosis and during the follow-up. RESULTS: Nine of 90 patients with Ménière's disease also had BPPV, which manifested in different ways. In 3 patients, BPPV preceded the onset of Ménière's symptomatology in the same ear; in 1, BPPV manifested after treatment for Meniere's disease had ended and the patient was in complete control of the spontaneous spells of vertigo; in 5 cases, recurrences of both Meniere's disease and the positioning symptomatology coincided. Treatment for each condition was conducted independently and favorable results were obtained after long-term follow-up when Meniere's disease and BPPV did not coincide simultaneously. In the group manifesting symptoms of both disorders at the same time, gentamycin treatment with the Canalith Repositioning Procedure and/or Semont maneuver partially resolved the symptoms. CONCLUSIONS: In the context of Ménière's disease, the sequence of appearance of BPPV relative to the spontaneous episodes must be taken into account when planning the treatment for each of the disorders, which should be considered independently. This pattern could also influence the prognosis for each disorder.  相似文献   
50.
Ventral hernia repair: a study of current practice   总被引:5,自引:5,他引:0  
Ventral wall hernias are common; despite this, there are no guidelines on the best surgical management. The aim of this study was to examine the types of repair in use for abdominal wall hernias in the West of Scotland over a 3-month period. Data were gathered on 120 patients. There were 60 incisional, 32 umbilical, and 28 epigastric hernias. The main indication for repair was pain (78%), while 12 patients (10%), presented acutely with incarceration or strangulation. The most common method of repair was sutured (55%), followed by mesh (29%) and Mayo repair (16%). There was no correlation between use of mesh and hernia size or whether repair was for a recurrent hernia. Surgical practice varies widely in the repair of ventral wall hernias. Clinical trials are required to establish the best method of repair for this common condition. Electronic Publication  相似文献   
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