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991.
Data were pooled from 11 studies evaluating supplemental fat sources differing primarily in degree of saturation (tallow, animal-vegetable fat, vegetable oil, and hydrogenated fats). Data were standardized as proportions of the respective controls to reduce variation among individual studies and were subjected to stepwise multiple regression against the iodine value of fats, the percentage increases of total fatty acids in diets above the respective controls, or the ratio of total C16 to C18 fatty acids in fats (only for hydrogenated fats). Increased iodine value (increasing unsaturation) of fats increased apparent fatty acid digestibility, especially as iodine value increased from 11 to 27. For partially hydrogenated fat sources, as the ratio of C16 to C18 fatty acids increased, digestibility also increased, especially with increasing iodine value (positive interaction). Beneficial effects of higher C16:C18 ratio were reduced as amount of added fat increased (negative interaction). Dry matter intake and FCM production decreased as iodine value increased, perhaps because of inhibition of fiber digestion or metabolic regulation of DMI. Milk protein percentage depression averaged .2 percentage units for most fats. However, as partially hydrogenated fat sources became more saturated, milk protein depression appeared to be less evident; increased ratio of C16:C18 of fatty acids appeared to increase milk protein percentage. Despite the lower apparent digestibility of fatty acids of hydrogenated fats, increased milk production and percentages of fat and protein appeared to make them more economical than more unsaturated fats.  相似文献   
992.
A detailed analysis of the developmental potential of parthenogenetic embryonic stem cells (PGES) was made in vivo and in vitro, and a comparison was made with the development of cells from parthenogenetic embryos (PG). In vivo, in chimeras with normal host cells (N), PGES cells showed a restricted tissue distribution consistent with that of PG cells, suggesting faithful imprinting in PGES cells with respect to genes involved in lineage allocation and differentiation. Restricted developmental potential was also observed in teratomas formed by ectopic transfer under the kidney capsule. In contrast, the classic phenotype of growth retardation normally observed in PG<==>N chimeras was not seen, suggesting aberrant regulation in PGES cells of genes involved in growth regulation. We also analysed the expression of known imprinted genes after ES cell differentiation. Igf2, H19 and Igf2r were all appropriately expressed in the PGES derived cells following induction of differentiation in vitro with all-trans retinoic acid or DMSO, when compared with control (D3) and androgenetic ES cells (AGES). Interestingly, H19 was found to be expressed at high levels following differentiation of the AGES cells. Due to the unexpected normal growth regulation of PGES<==>N chimeras we also examined Igf2 expression in PGES derived cells differentiated in vivo and found that this gene was still repressed. Our studies show that PGES cells provide a valuable in vitro model system to study the effects of imprinting on cell differentiation and they also provide invaluable material for extensive molecular studies on imprinted genes. In addition, the aberrant growth phenotype observed in chimeras has implications for mechanisms that regulate the somatic establishment and maintenance of some imprints. This is of particular interest as aberrant imprinting has recently been invoked in the etiology of some human diseases.  相似文献   
993.
Chronic intussusception is defined as intussusception lasting for 14 days or more. Because the clinical manifestation is different from that of acute intussusception, the diagnosis is usually delayed or missed. Ultrasonography is of diagnostic value. We present a 8-year-old boy who had the complaints of marked body weight loss and intermittent abdominal pain for one month. Hydrostatic reduction failed in this case. Laparotomy revealed an ileo-colic intussusception, the leading point of which was a colonic polyp. We would like to emphasize that chronic intussusception frequently appears a nonacute abdominal condition, usually intermittent abdominal pain, and sometimes marked body weight loss and an abdominal mass. Surgical intervention is usually needed in older children because a high incidence of underlying lesions in them.  相似文献   
994.
Collagen-induced arthritis (CIA) is a T-cell-dependent rat model of rheumatoid arthritis (RA) that is induced by injection of collagen type II in incomplete Freund's adjuvant. Neovascularization within the synovium is a prominent feature of CIA and RA. The novel angiogenesis inhibitor AGM-1470 and the microtubule-stabilizing agent Taxol represent two new classes of agents with specific mechanisms of action. AGM-1470 inhibits fibroblast growth factor-induced stimulation of endothelial cell migration, endothelial cell proliferation, and capillary tube formation, resulting in effective suppression of new blood vessel formation. By enhancing microtubule polymerization, Taxol interferes with normal microtubule function in cell mitosis, migration, chemotaxis, and intracellular transport. Using a suppression protocol in established CIA, the effects of AGM-1470 and Taxol as single agents and in combination were evaluated. Combination therapy significantly reduced clinical arthritis compared to control rats (P < 0.00001). The combination therapy group also experienced earlier and significantly greater reduction of clinical arthritis compared to either single agent-treated groups (P < 0.05). Blinded radiographic scores at the end of the study demonstrated less soft tissue swelling and joint destruction using combination therapy than either single agent. This is the first use of AGM-1470 and Taxol in combination therapy. Further study of agents with distinct mechanisms of action may lead to more effective treatment options in chronic inflammatory arthritis and to a better understanding of the pathophysiologic processes of pannus formation.  相似文献   
995.
OBJECTIVE. To determine the one-year outcome for patients with a chief complaint of dizziness that had persisted at least two weeks. DESIGN: Prospective cohort study. SETTING: Federal teaching hospital. PATIENTS: 100 dizzy patients and 25 control subjects. MEASUREMENTS: The primary outcome was dizziness status (improved or not improved); the secondary outcomes were morbidity and health care utilization. RESULTS: The dizziness resolved for 18 patients, whereas the status improved for 37, stayed the same for 32, and worsened for 11, with two patients lost to follow-up. Thus, 55% of patients whose dizziness had not resolved two weeks after their initial visits improved over the subsequent 12 months. Logistic regression revealed four independent predictors of persistent dizziness at one-year follow-up: dizziness due to psychiatric causes, dysequilibrium, vertigo other than benign positional vertigo, vestibular neuronitis, or migraine (odds ratio, 6.3; 95% CI, 2.1-18.6); daily dizziness (odds ratio, 6.4; 95% CI, 2.0-21.0); dizziness worse with walking (odds ratio, 3.0; 95% CI, 1.1-9.0); and patient had initially feared a serious illness (odds ratio, 0.25; 95% CI, 0.10-0.74). These four factors could be used to classify patients as having either a high (82%), medium (47%), or low (0%) likelihood of improvement at one-year follow-up. One patient died from heart failure, and none developed a serious disease for which dizziness had been a harbinger. Dizziness was not associated with an increased number of clinic visits. CONCLUSIONS: Among patients with a chief complaint of dizziness who are still symptomatic at two-week follow-up, more than half improve within a year. Clinical factors identify patients at higher risk for persistent dizziness.  相似文献   
996.
PURPOSE: To characterize the imaging features of mediastinal hemangioma. MATERIALS AND METHODS: The authors retrospectively reviewed chest radiographs and computed tomographic (CT) scans from 14 patients with mediastinal hemangioma. RESULTS: Most mediastinal hemangiomas manifested as well-marginated masses at CT. Three masses had punctate calcifications, and one had phleboliths. Five masses were of heterogeneous attenuation at unenhanced CT. Ten of 11 (91%) hemangiomas were of heterogeneous attenuation at contrast material-enhanced CT, and the following four patterns were observed: central (n = 6, 60%), mixed central and peripheral (n = 2, 20%), peripheral (n = 1, 10%), and nonspecific (n = 1, 10%) increased attenuation. Central increased attenuation was observed more frequently after administration of a bolus of contrast material than after slow infusion. CONCLUSION: Hemangiomas should be considered in the differential diagnosis of well-marginated mediastinal masses that have heterogeneous attenuation on CT scans, show central enhancement after administration of contrast material or contain punctate calcification.  相似文献   
997.
Noise exposure of a population sample living in a city in northern Italy (Genoa) was assessed by measuring the noise in the area as well as with personal sound detectors. Sampling was conducted during a standard day and covered a period of time spent out-of-doors, at work (service sector) and at home. Ambient noise at home and at work was assessed with sound-level meters, personal exposure levels were assessed with personal sound-level/dosimeters. Information regarding each environment was obtained with an interview including also a subjective judgement on traffic intensity and noise levels. The mean individual equivalent continuous sound level (Leq) of recorded noise was 74.5 dB(A) for 24 h and 63.9 dB(A) at night. A further distinction was made between noise exposure at home (Leq 74.4), work (Leq 74.0) and during city transfers (Leq 79.3). Leq values for individual hours, Leq daytime (Leq, d), Leq nighttime (Leq,n) and Leq day-night (Ldn) indices calculated in the different environments, i.e. at work, home and out-of-doors, are reported here. Individual noise levels have then been compared with environmental data and with subjective noise exposure judgement.  相似文献   
998.
The 25-nm diameter parvovirus capsid is assembled from 60 copies of a sequence common to the overlapping VP1 and VP2 proteins. Here we examine the epitope specificity's of 28 monoclonal antibodies (MAb) prepared against canine parvovirus (CPV), feline panleukopenia virus (FPV), and raccoon-dog parvovirus or blue (Arctic) fox parvovirus. Comparing the reactivity of those MAb with various MAb-selected escape mutants, or with natural variants of CPV or mink enteritis virus (MEV) which differ at known sequences, showed that the binding of 20 of those MAb was strongly affected by variations of two regions on the threefold spike of the CPV capsid. One region was adjacent to the tip of the threefold spike, and the second was around VP2 residue 300, on the shoulder of that structure. MAb recognizing both antigenic sites efficiently neutralized the virus infectivity and inhibited hemagglutination. Mutations leading to natural antigenic variation have also been observed in both those sites in naturally variant strains of CPV or MEV, suggesting that they are important antigenic structures on these parvoviruses. The bindings of several MAb were not affected by the mutations at those antigenic sites, indicating that they recognized other, and perhaps conserved, structures.  相似文献   
999.
Despite the clear benefits of treating established hypertension, this approach alone will not prevent all of the blood pressure-related cardiovascular-renal disease in the community. Primary prevention of hypertension is a natural extension of hypertension treatment which provides opportunity to reduce costly cycle of managing hypertension and its complications. The purpose of this report is to guide practician physicians and health professionals in their care of hypertensive patients. In order to provide specific guidelines, a new classification schema of high blood pressure that includes systolic as well diastolic levels is proposed (source, Joint National Committee on Detection, Evaluation and Treatment of High Blood Pressure 1993). Furthermore, recommendations for follow-up based on initial set of blood pressure measurements, life-style modifications and pharmacologic therapy are proposed, suggesting a new treatment algorithm in which diuretics and beta-blockers are preferred as first-choice agents because their confirmed reduction in morbidity and mortality (unless they are contraindicated or unacceptable), but including an expanded list of agents that are suitable for initial monotherapy and guidelines for selecting and individualizing the antihypertensive drug regimen.  相似文献   
1000.
OBJECTIVE: The present study investigates the comorbidity between bulimia nervosa (BN) and the entire range of American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, 3rd rev. ed. (DSM-III-R) personality disorders and controls for the presence of coexisting depression. METHOD: The Personality Disorders Examination (PDE), a structured interview that encompasses all 13 (provisional) DSM-III-R personality disorders, was administered to three groups of subjects: depressed BN patients (n = 15), nondepressed BN patients (n = 15), and nonpsychiatric controls (n = 15). The BN patients were referrals to a dieting disorder unit affiliated with the University of Sydney. They all met DSM-III-R criteria and all had body mass indexes (BMIs) greater than 19. The nonpsychiatric control group were recruited from an undergraduate psychology course. All subjects were given the Bulimic Investigatory Test, Edinburgh (BITE), the Eating Disorders Inventory-2 (EDI-2), the Hamilton Depression Rating Scale (HDRS), and the PDE. RESULTS: 46.7% of depressed BN patients met the criteria for at least one Axis II diagnosis, as assessed by the PDE, and 33.3% of nondepressed BN patients received such a diagnosis, whereas only 6.7% of nonpsychiatric control subjects met this criterion (p < .05). The results of the present study provide support for an increased comorbidity between personality disorders and BN that cannot be attributed to the confounding influence of coexisting depression. DISCUSSION: This finding enables the identification of subgroups of individuals with BN, enabling them to be compared and contrasted. The identification of differences between subgroups may provide information regarding prognosis and differential response to treatment, which could enable more appropriate treatment decisions to be made.  相似文献   
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