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41.
The antitussive compound Levodropropizine (LD) is active in animal bronchoconstriction induced by histamine and capsaicin and in man protects from bronchoconstriction induced by capsaicin. The primary objective of this study was to evaluate the mechanism of action of LD given at 60 mg t.i.d. as oral drops, for 8 days by means of specific bronchial challenges (allergens) and of aspecific challenges acting via different receptors and fibers (i.e. metacholine via cholinergic receptors and ultrasonically nebulized distilled water (UNDW) via histamine and neuropeptide release). The study design is randomized, double-blind, cross-over versus placebo in 30 allergic asthmatic patients. Baseline bronchial tone and bronchoconstrictor response to metacholine (MCh) were not modified by active treatment nor by placebo. On the contrary, in airway responsiveness to UNDW, the active treatment showed an antagonist effect against induced bronchoconstriction of 59% [activity ratio (AR) as antilog = 0.41; 95% confidence interval 0.35-0.54; p < or = 0.05] in comparison to no effect for placebo. Similarly, in airway responsiveness to specific allergen, active treatment antagonized the bronchoconstrictor effect of grass pollen by 83% and of various allergens (dermatophagoides and grass pollen) by 72%, i.e. AR of 0.17 (95% confidence interval 0.045-0.65; p < 0.01) and of 0.28 (95% confidence interval 0.07-1.04; p < 0.05), respectively. No antagonist effect was evident with placebo at all times. Besides inhibiting cough, LD is also partially effective in inhibiting bronchial hyperreactive response against specific allergen and UNDW bronchoconstriction. Hence, LD might act by partly inhibiting histamine and neuropeptide release.  相似文献   
42.
The aim of these experiments was to study the effect of early enteral nutrition with either standard or enriched (arginine, n-3 fatty acids, RNA) enteral formulas on translocation of bacteria from the gut and acute mortality rate following thermal injury. In the first experiment 60 Balb c mice were gavaged with 10(10)Escherichia coli and received a 20% burn injury. In 40 mice enteral nutrition (20 standard, 20 enriched) was started immediately after injury and stopped 36 h later. In the control group (n = 20) aliquotes of Ringer's solution was administered intragastrically. Mortality rate was observed for 10 days post-injury. In the second experiment 60 Balb c mice were gavaged with 10(10)E. coli labelled with biotin(111) Indium and then burned. In 40 mice enteral nutrition (20 standard, 20 enriched) was started immediately after burn. The control group (n = 20) received aliquotes of Ringer's solution. 4 h after injury all animals were sacrificed and liver, lungs, kidneys, spleen and systemic blood were harvested, and radionuclide counts were measured. No animal died after day 3 post-burn. The mortality rate was significantly lower at day 1 in the groups infused with both enteral solutions (15%) compared to controls (30%; p = 0.05). At day 3 the animals fed with the enriched diets showed a lower mortality (5%) versus the standard and control groups (10%). Bacterial translocation to the liver and lungs was significantly higher in Ringer's group than in both enterally fed groups. Early post-burn enteral nutrition reduces both translocation and acute mortality. Supplementation of the diets with specific nutrients appears to exert additional advantages on outcome.  相似文献   
43.
The results of analysis of auditory brain- stem evoked responses (ABRS) are reported in 173 patients with delayed speech (DS). The mean age of the patients is 4.6 years (age ranges from 1.4 years to 10 years). The patients were classified into 5 groups based on ABR findings:
–  Group I (62 patients) had normal hearing threshold and peak- interpeak latencies. The mean amplitude of wave I was however, not significantly low (p < 0.03).
–  Group II (27 patients) had an increased hearing threshold (40 dB), mild delay in the mean absolute peak latency of wave I (p < 0.03), decreased I– IV interval (p < 0.03), but highly significant reduction of wave I amplitude (p < 0.004). There is also a significant latency delay (p < 0.001) and amplitude reduction (p < 0.05), when this wave is compared with that a Group I (as control). These observations are suggestive of mild degree of peripheral hearing deficit in this group.
–  Group III (49 patients) had gross ABR abnormalities of various nature and hence may be sub- grouped into (a) SNHL cochlear type (55%) (b) SNHL retrocochlear type (4%) and (c) severed degree of SNHL undecisive group (41%). Ten patients (2.7%) among the sub- group (a) had unilateral hearing loss and another 3 had Down’s syndrome.
–  Group IV (conductive deafness) had an increased hearing threshold and shifting of ABR waves towards right with normal I– V interval. Only 6 patients were found in this group. It may be that conductive deafness is less important as a cause.
–  Group V (29 patients) had no responses at repeated ABR studies even at higher intensity of 95 dB, the ABR studies of this group correlates with the clinical evaluation of profound deafness. The delayed speech development in 84 patients (from Groups III, IV and V) may be caused by severe degree of hearing deficit as indicated by marked ABR abnormalities. If the mild peripheral hearing loss in Group II is added to the above groups, ABRs could identify 64.6% of our patients with hearing deficit. Hence, ABR test is most reliable and sensitive diagnostic test in detecting hearing loss, a common cause of delayed speech development in children.
  相似文献   
44.
In December 2019, a new viral respiratory infection known as coronavirus disease 2019 (COVID-19) was first diagnosed in the city of Wuhan, China. COVID-19 quickly spread across the world, leading the World Health Organization to declare it a pandemic on March 11, 2020. The disease is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a similar virus to those involved in other epidemics such as severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV). Epidemiological studies have shown that COVID-19 frequently affects young adults of reproductive age and that the elderly and patients with chronic disease have high mortality rates. Little is known about the impact of COVID-19 on pregnancy and breastfeeding. Most COVID-19 cases present with mild flu-like symptoms and only require treatment with symptomatic relief medications, whereas other cases with COVID-19 require treatment in an intensive care unit. There is currently no specific effective treatment for COVID-19. A large number of drugs are being used to fight infection by SARS-CoV-2. Experience with this therapeutic arsenal has been gained over the years in the treatment of other viral, autoimmune, parasitic, and bacterial diseases. Importantly, the search for an effective treatment for COVID-19 cannot expose pregnant women infected with SARS-CoV-2 to the potential teratogenic risks of these drugs. Therefore, it is necessary to determine and understand the safety of anti-COVID-19 therapies prior to conception and during pregnancy and breastfeeding.Key words: COVID-19, SARS-CoV-2, antiviral, pregnancy, breastfeeding  相似文献   
45.
HYPOTHESIS: Perioperative administration of a supplemented enteral formula may reduce the rate of postoperative infections. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: Department of surgery at a university hospital. PATIENTS: Two hundred six patients with neoplasm of colorectum, stomach, or pancreas. INTERVENTION: Patients were randomized to drink 1 L/d of either a control enteral formula (n = 104) or the same formula enriched with arginine, RNA, and omega3 fatty acids (n = 102) for 7 consecutive days before surgery. The 2 diets were isoenergetic and isonitrogenous. Jejunal infusion with the same formulas was started 6 hours after operation and continued until postoperative day 7. MAIN OUTCOME MEASURES: Rate of postoperative infectious complications and length of hospital stay. RESULTS: Both groups were comparable for age, sex, weight loss, Karnofsky scale score, nutritional status, hemoglobin level, duration of surgery, blood loss, and rate of homologous transfusion. Intent-to-treat analysis showed a 14% (14/102) infectious complication rate in the supplemented group vs 30% (31/104) in the control group (P = .009). In the eligible population, the postoperative infection rate was 11% (9/85) in the supplemented group vs. 24% (21/86) in the control group (P = .02). The mean +/- SD length of postoperative stay was 11.1+/-4.4 days in the supplemented group and 12.9+/-4.6 in the control group (P = .01). CONCLUSION: Perioperative administration of a supplemented enteral formula significantly reduced postoperative infections and length of stay in patients undergoing surgery for cancer.  相似文献   
46.
Gallium 67 imaging was used in 12 patients with documented Hansen's disease undergoing treatment or not, in an attempt to determine the pattern of the disease. Diagnosis was confirmed by histopathology in all patients. The Mitsuda reaction was seen in all patients. Specific nuclear studies were performed when needed to evaluate particular organs better. Gallium 67 images show homogeneous, diffuse and moderate accumulation over the entire skin surface (except for the face) of untreated patients with multibacillary disease. The facial skin in these cases presented homogeneous, diffuse but very marked uptake of gallium. Internal organ involvement was variable. There was a very good correlation among clinical, scintigraphic, immunological and histopathological data. The pattern of the body skin (skin outlining) and facial skin (beard distribution) may be distinct for untreated patients with multibacillary leprosy.  相似文献   
47.
The aim of this study was to evaluate the usefulness of a major secretory protein of human chondrocytes (chondrex) as a potential serum marker of bone responsiveness to growth hormone (GH). The study included 18 children (10 F, 8 M), aged 10.9 ± 2.3 years, bone age 8.8 ± 2.7 years, height −2.3 ± 0.22 SDS, affected by isolated idiopathic GH deficiency (GHD). Serum samples for evaluation of chondrex, total, and bone alkaline phosphatase were taken before and 3 and 6 months following treatment with rhGH. The basal serum level of chondrex did not differ between patients (37 ± 22 ng/ml) and controls (33 ± 9.8 ng/ml). Following 6 months of treatment with rhGH, a significant increase of height velocity SDS (from −2.8 ± 0.5 to 1.3 ± 0.7), total (from 195 ± 47 to 264 ± 79 U/liter) and bone alkaline phosphatase (from 81 ± 21 to 108 ± 30 U/liter) was observed, while chondrex serum level remained unchanged (from 37 ± 22 to 36 ± 29 ng/ml). It was concluded that chondrex cannot be considered a reliable marker of bone responsiveness to GH in the growing child. Received: 19 March 1999 / Accepted: 3 February 2000  相似文献   
48.
49.
Carnivorous mollusks belonging to the genus Conus paralyze their prey by injecting a rich mixture of biologically active peptides. Conus regius is a vermivorous member of this genus that inhabits Brazilian tropical waters. Inter-, intra-species and individual variations of cone snail venom have been previously reported. In order to investigate intra-specific differences in C. regius venom, its feeding behavior and the correlation between these two factors, animals were pooled according to gender, size and season of collection, and their venom composition was compared by high performance liquid chromatography (HPLC). Both the whole venom and one specific peak were monitored by HPLC. Chromatographic profiles revealed no significant differences in their peak areas, indicating that the venom composition, based solely in the presence or absence of the major peaks, is stable regardless of season, gender and size. Therefore, analysis of one given toxin, eluting in one of the major peaks, is representative among the population. Moreover, this work presents the identification of one novel conotoxin (rg11a), which amino acid sequence was deduced by mass spectrometry.  相似文献   
50.
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