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1.
A total of 1010 dry cows and pregnant heifers was randomly selected from 25 dairy farms near Guelph, Ontario, Canada to receive either a controlled-release capsule of monensin or a placebo at 3 wk prior to expected calving. Serum samples were obtained at the time of treatment administration, and both serum and milk samples were collected at wk 1, 2, 3, 6, and 9 postcalving. The threshold used to define subclinical ketosis was selected a priori at a concentration of > or = 1200 mumol/L of beta-hydroxybutyrate. Using this threshold, the prevalence and incidence of subclinical ketosis were significantly reduced (50%) by monensin treatment. The duration of subclinical ketosis for cows that had been treated with monensin was also shorter than that for cows treated with the placebo. Monensin treatment significantly reduced the incidence of subclinical ketosis when the threshold was defined using higher concentrations of serum beta-hydroxybutyrate (1400 and 2000 mumol/L). In addition, monensin significantly reduced the prevalence of positive milk ketone tests.  相似文献   

2.
CONTEXT: In British Columbia, human immunodeficiency virus (HIV)-infected persons eligible for antiretroviral therapy may receive it free but the extent to which HIV-infected injection drug users access it is unknown. OBJECTIVE: To identify patient and physician characteristics associated with antiretroviral therapy utilization in HIV-infected injection drug users. DESIGN: Prospective cohort study with record linkage between survey data and data from a provincial HIV/AIDS (acquired immunodeficiency syndrome) drug treatment program. SETTING: British Columbia, where antiretroviral therapies are offered free to all persons with HIV infection with CD4 cell counts less than 0.50 x 10(9)/L (500/microL) and/or HIV-1 RNA levels higher than 5000 copies/mL. SUBJECTS: A total of 177 HIV-infected injection drug users eligible for antiretroviral therapy, recruited through the prospective cohort study since May 1996. MAIN OUTCOME MEASURES: Patient use of antiretroviral drugs through the provincial drug treatment program and physician experience treating HIV infection. RESULTS: After a median of 11 months after first eligibility, only 71 (40%) of 177 patients had received any antiretroviral drugs, primarily double combinations (47/71 [66%]). Both patient and physician characteristics were associated with use of antiretroviral drugs. After adjusting for CD4 cell count and HIV-1 RNA level at eligibility, odds of not receiving antiretrovirals were increased more than 2-fold for females (odds ratio [OR], 2.53; 95% confidence interval [CI], 1.08-5.93) and 3-fold for those not currently enrolled in drug or alcohol treatment programs (OR, 3.49; 95% CI, 1.45-8.40). Younger drug users were less likely to receive therapy (OR, 0.47/10-y increase; 95% CI, 0.28-0.80). Those with physicians having the least experience treating persons with HIV infection were more than 5 times less likely to receive therapy (OR, 5.55; 95% CI, 2.49-12.37). CONCLUSIONS: Despite free antiretroviral therapy, many HIV-infected injection drug users are not receiving it. Public health efforts should target younger and female drug users, and physicians with less experience treating HIV infection.  相似文献   

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As a basic study for future diagnosis of cutaneous leishmaniasis, we tried to detect Leishmania parasites representing different species in the subgenera Leishmania and Viannia from subject patients with cutaneous leishmaniasis by using the polymerase chain reaction (PCR) with the subgenus Viannia specific primer. Four out of the 14 specimens revealed an amplified DNA of 70 bp specific for the subgenus Viannia (L. braziliensis complex). No bands were detected in the rest of the specimens belonging to the subgenus Leishmania and unclassified groups. The base sequences of the amplified DNA corresponded with those of the L. (V). braziliensis kinetoplast minicircle. We concluded that PCR using the present primer specific for the subgenus Viannia would be useful in detecting Leishmania parasites in lesions of cutaneous leishmaniasis caused by the L. braziliensis complex.  相似文献   

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Paraplegia affected 14 hedgehogs (Erinaceus europaeus) in a wildlife rescue hospital over a period of six months. Postmortem examination revealed demyelination in the brain and spinal cord and an inflammatory response in the meninges, choroid plexus and CNS. The peripheral nervous system was not affected. In the spleen, lungs and liver there was an accumulation of megakaryocytes and other evidence of extramedullary haemopoiesis, but there was no haematological evidence of anaemia. The pattern of disease incidence and the nature of the changes in the CNS suggest they were of viral origin, but no causal agent was isolated and the possibility of a neurotoxin cause cannot be ruled out.  相似文献   

8.
Previous studies by U. Halsband and the present author (see PA, Vol 69:570; see also 1985) showed that after removal of premotor cortex, monkeys were poor at selecting movements on the basis of a visual contextual cue. In those experiments, Ss had to pull or turn a handle depending on the color of a cue presented in the foreground or background. In the present 2 experiments, with 11 rhesus monkeys, Ss with lesions that included the premotor cortex could select movements correctly if the cue was given by information about the handle itself. In Exp I, the cue was provided by the direction in which the Ss had last moved the handle; Ss were required to squeeze a handle if they had been forced to squeeze it 5 sec earlier and to turn it if they had been forced to turn it. In Exp II, the cue was provided by the identity of the handle itself. When presented with a blue handle, Ss had to pull the handle; when presented with a yellow handle, they had to turn it. It is argued that animals with premotor lesions are impaired only when the task is a true conditional task. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

9.
Plasma lipoprotein(a) (Lp(a)) concentrations vary considerably between individuals. To examine the variation for products of the same and different apolipoprotein(a) (apo(a)) alleles, conditions were established whereby phenotyping immunoblots could be used to estimate the concentration of Lp(a) associated with the constituent apo(a) isoforms. In these studies 28 distinct isoforms were identified, each differing by a single kringle IV unit. Tracking the isoforms through 10 families showed that there could be up to 200-fold difference in the Lp(a) concentration associated with the same-sized isoform produced from different alleles. In contrast there was typically < 2.5-fold variation in the Lp(a) concentration associated with the same allele. However, there were four occasions where the concentration associated with a particular allele was reduced below the typical range from one generation to the next. A nonlinear, inverse trend with isoform size was apparently superimposed upon the other factors that determine Lp(a) concentration. Inheritance of familial hypercholesterolemia or familial-defective apoB100 had little consistent effect upon Lp(a) concentration. In both the families and in other unrelated individuals the distribution of isoforms and their associated concentrations provided evidence for the presence of at least two and possibly more subpopulations of apo(a) alleles with different sizes and expression.  相似文献   

10.
In this study, 400 clinically anterior cruciate ligament (ACL) deficient knees were arthroscoped and studied prospectively in the period January 1986 to April 1992. An ACL tear was always confirmed, and 41 per cent of these patients did not have an associated meniscal tear. In 30.25 per cent the lateral meniscus was torn; in 21.25 per cent the ACL tear was associated with a medial meniscus tear, and in the remaining 7 per cent both menisci were torn. The most frequently associated meniscal injury was the bucket handle tear of the medial meniscus (9 per cent), followed by the posterior horn tear of the lateral meniscus, which showed the same frequency as the ragged (or degenerated) tear of the lateral meniscus (6 per cent). The horizontal tear of the posterior part of the lateral meniscus showed a prevalence of 4.3 per cent. This picture is probably dependent on a secondary referral nature of the centre surveyed, in which the average time between injury and arthroscopy was 23.3 months.  相似文献   

11.
Acute respiratory infections (ARI) are a major cause of morbidity in children worldwide, and are estimated to cause four million deaths per year, mainly in the developing world. In those countries, bacterial infection with high case fatality is common, apparently following a primary viral infection. The case management strategy has had success in controlling severe outcomes. However, its dependence on the use of antibiotics and the advantage of primary prevention support the need for vaccines. Vaccines against viruses such as respiratory syncytial and parainfluenza would prevent what is often the initial infection and vaccines against Haemophilus influenzae and S. pneumoniae the major bacterial causes of mortality. Maternal immunization may have special relevance in developing countries where protection early in life is required. The development of combination vaccines would also be especially useful, since contacts with the medical system are often difficult. The introduction and use of new vaccines in those regions will require demonstration of cost effectiveness and acceptance by policy makers.  相似文献   

12.
Since portal hypertension affects the gastric mucosa, leading to congestive gastropathy and thus to increased incidence of bleeding, it is one of the possible causes of increased permeability of gastric mucosal capillaries. The aim of this study was the quantitative assessment of the permeability of the gastric mucosal endothelial cells. Eight CCl4-induced cirrhotic rats and eight matched controls were subjected to i.v. injection of FITC-albumin, and a morphometric evaluation of fluorescence in serial histological sections of the gastric mucosa was performed by a video image analysis system. Fluorescence was found to be 0.351 +/- 0.01% of the area scanned in experimental animals versus 0.073 +/- 0.005% in controls, i.e. it was significantly increased by the treatment, which implies a significant endothelial leakage into the extravascular space.  相似文献   

13.
Three studies with 9 rhesus monkeys examined whether removal of the tissue of sulcus principalis affected Ss' memory for a list of spatial locations. Findings show that 3 Ss whose tissue in the sulcus principalis had been removed were no longer able to search effectively for food, relative to 3 unoperated controls, when given 25 spatial locations to remember. A less marked deficit was apparent in 3 Ss whose superior prefrontal convexity had been removed. Ss with sulcus principalis lesions learned as quickly as other Ss to choose between locations on the basis of a spatial cue, and they did not take significantly longer to shift from a previously rewarded location. Findings are considered in relation to the deficits observed in humans with unilateral frontal lesions and the possibility that frontal mechanisms operate on information in working memory. (55 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

14.
CONTEXT: Inner-city immunization rates have lagged behind those in other areas of the country. OBJECTIVE: To evaluate the impact of an initiative linking immunization with distribution of food vouchers in the inner city. DESIGN: Retrospective analysis of immunization data gathered in 1996 and 1997. SETTING: Nineteen Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) sites serving 30% of the Chicago, III, birth cohort. PARTICIPANTS: A total of 16581 children 24 months old or younger. INTERVENTIONS: Voucher incentives (varying frequency of food voucher issuance based on immunization status) and assessment of immunization status and referral to immunization provider. MAIN OUTCOME MEASURES: Age-appropriate immunization rates and WIC enrollment rates. RESULTS: During the 15-month period of evaluation, immunization rates increased from 56% to 89% at sites performing voucher incentives. The proportion of children needing voucher incentives declined from 51% to 12%. Sites performing assessment and referral, but not providing voucher incentives, showed no evidence of improvement in immunization coverage. No difference was observed in enrollment rates between sites performing voucher incentives and those that did not. CONCLUSION: Applied in a large-scale, programmatic fashion, voucher incentives in WIC can rapidly increase and sustain high childhood immunization rates in an inner-city population.  相似文献   

15.
A small number of children who develop disconjugate nystagmus, torticollis, and head titubation (spasmus nutans) have been found to have optic chiasm or third ventricle gliomas. However, the prevalence of glioma or other developmental abnormalities in this disorder is unknown because no large series of spasmus nutans cases has previously been reported. A reviewer of the records of 67 consecutive children initially diagnosed with spasmus nutans and followed for an average of 3.3 years at the St Louis Children's Hospital revealed the following: 61% had a history of prematurity, developmental delay, or other systemic abnormality; strabismus, most commonly infantile esotropia, developed in 55%; 43% had neuroimaging studies; and 0% had evidence of a glioma or showed signs of tumor on follow-up examinations. From this consecutive patient series, we estimate the prevalence of tumor in spasmus nutans to be less than 1.4%. Without other evidence of an intracranial mass lesion, neuroimaging of infants initially diagnosed with spasmus nutans may not be immediately warranted.  相似文献   

16.
This study involved 182 calves, heifers and cows that were the first generation progeny of cows with bovine spongiform encephalopathy (BSE). All animals underwent clinical and neurological examinations. Blood, milk, urine, ruminal fluid and cerebrospinal fluid samples were examined. Each cow underwent a specific examination for BSE which included assessment of behaviour, sensitivity and locomotion. This examination was performed twice, and there was very good agreement between the results. The most common symptom was nervousness (14 animals). In the first examination, 68 animals were mildly to moderately sensitive to touching of the head, 44 animals were hypersensitive to a halogen light and 35 animals were hypersensitive to a camera flash. Twenty-four animals reacted by kicking when the hindlimbs were touched with a broom. None of the animals had disturbances in locomotion. Based on the interpretation of all findings and the comparison of the results of the first and second examinations, 173 animals were diagnosed as free of BSE. In 9 animals, the disease could not be ruled out; however, it could not be confirmed in any of them. Histological and immunohistochemical examinations of the brain of all animals were negative for BSE (see Part 2 of the study for details). The results of this study indicate that abnormal clinical findings may occur in clinically healthy cattle. However, none of the progeny of cows with BSE exhibited clinical signs typical of BSE, such as disturbances in behaviour; sensitivity and locomotion.  相似文献   

17.
12 normal New Zealand white rabbits and 12 with septal lesions received classical differential conditioning of the nictitating membrane response (NMR), followed by auditory generalization tests run in extinction. Although rate of acquisition and asymptotic responding to positive conditioned stimuli did not differ, septals responded more than normals to nonreinforced stimuli. Resultant decrements in differential conditioning could not be attributed to changes in auditory or shock thresholds or to increased spontaneous NMRs. Septals also responded at higher rates in both operant conditioning (barpresses reinforced with food pellets on a variable interval schedule) and extinction sessions. No difference in suppression in a passive avoidance task was found. Results are discussed in relation to R. A. McCleary's (1966) response disinhibition analysis of septal function, and an habituation hypothesis is considered. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

18.
This experiment examined the effect of complete diets composed of 60% grass silage and 40% concentrate based mainly on beet pulp, ground wheat, wheat treated with NaOH, or ground corn on milk production and ruminal fermentation of dairy cows. Milk production and fat yield were 19.8, 20.7, 20.1, and 21.2 kg/d and 0.71, 0.76, 0.72, and 0.78 kg/d, respectively (18 cows per treatment). Cows fed the diet based on ground corn had higher milk production and fat yield, but lower milk protein concentration, than did cows fed the diet based on beet pulp. Cows fed the diet based on ground corn also had higher fat yields than did cows fed the diet based on wheat treated with NaOH. Cows fed the diet based on ground wheat had lower ruminal pH than did cows fed the diet based on beet pulp (6.34 vs. 6.59) and higher ruminal NH3 concentrations (6.2 vs. 5.2 mmol/L) than did cows fed the diet based on ground corn. These results showed little difference in milk production based on wheat processing method and little advantage to replacing beet pulp with either wheat type in a high forage diet. However, milk production and fat yield were increased by replacing beet pulp with ground corn.  相似文献   

19.
The effects of bovine somatotrophin (bST) on ovarian follicle development and function and associated gonadotrophin profiles during the first nine weeks post partum were investigated in beef cows. Thirty-two cows (Shorthorn x Galloway) in moderately low body condition (BC) at calving were fed to maintain BC thereafter. At Weeks 2, 4, 6 and 8 post partum, animals were injected with 320 mg bovine somatotrophin (bST) (T, treated; n = 17) or with the carrier oil only (C, control; n = 15). Ovulation occurred in 4 of 17 T cows and 0 of 15 C cows (P = 0.10) by nine week post partum. Treatment with bST did not affect the numbers of small (3-8 mm in diameter) or large (> 8 mm in diameter) follicles or the granulosa cell populations but enhanced the oestradiol (P < 0.05) and insulin-like growth factor-I (IGF-I) content (P < 0.01) of large follicles by nine weeks post partum. It did not significantly affect the testosterone concentrations of large follicles. Circulating concentrations of growth hormone (GH) and IGF-I were higher in T cows than in C cows (P < 0.001) but were unrelated to gonadotrophin profiles or gonadotrophin receptor concentrations in the follicles. At Week 8, plasma insulin concentrations were higher in T cows than in C cows both before (P < 0.05) and after (P < 0.05) glucose injection. It is concluded that GH may play an important role in mediating the effects of nutritional state on ovarian function during the post-partum period, possibly through alteration of intrafollicular IGF-I concentrations.  相似文献   

20.
The appearance of pronounced cavity formation and erosion of the cortex layer in the area of the prosthetic shaft following total endoprosthetic implantation, without signs of an acute bacterial inflammatory activity, was investigated in specimens from the Orthopedic Hospital, Würzburg. The causes of these alterations, in most cases, could be electrogalvonic tension which produces inflammatory processes with lacunar disintegration of the cortex layer. In this process, the metal implant is loosened. In vitro experiments have shown that an average difference in potential of 290 mV can be established between both electrodes of the metal implant.  相似文献   

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