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71.
In rats treated systemically with either amphetamine, amfonelic acid or apomorphine, large numbers of cells displaying Fos-like immunoreactivity (FLI) could be seen in the lateral zone of the lateral habenula. The induction of FLI by amphetamine could be blocked either by pretreatment with haloperidol or by 6-hydroxydopamine lesions of ascending dopamine fibers at the level of the lateral hypothalamus. In contrast, a variety of stressors selectively induced FLI in the most medial portion of the lateral habenula. These findings support the concept of a functional differentiation of the medial and lateral regions of the lateral habenula and provide further evidence for involvement of the habenula in the circuitry of the basal ganglia.  相似文献   
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It is the purpose of the study to report the frequency of parvovirus in children with a diagnosis of Diamond-Blackfan anaemia and to discuss the possible aetiological role of parvovirus in Diamond-Blackfan anaemia. We found parvovirus DNA in 3 of 11 bone marrow smears. Giant pronormoblasts showed low sensitivity (33%) and poor specificity (75%). The presence of giant pronormoblasts was associated with a very high myeloid: erythroid ratio, and may not be specific for parvovirus infection, but a feature of severely suppressed erythropoiesis. The three parvovirus-positive patients were the only children who experienced a remission, and who are free of medication. The seven surviving parvovirus-negative patients are all currently on steroid treatment.  相似文献   
75.
Objective: To establish two stably KGF-transfected, immortalized cell lines. Methods: HaCaT-keratinocytes and KMST-6-fibroblasts were transfected by liposome mediated gene transfer. Transfection effectivity, gene integration and configuration of the transgenic protein were investigated by ELISA, DANN-PCR and β-Gal-staining. Results: Most effective GF producing clones were tested by a colorimetric XTT-test. Conclusion: This is a significant acceleration of cell proliferation and mitosis of human keratinocytes in an Air Liquid Interface (ALI) test system.  相似文献   
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Ho  A; Williams  DM; Zelenock  GB; Braunstein  EM 《Radiology》1987,162(2):573-574
Hypertrophic osteoarthropathy (HO) is a specific clinicoradiologic entity, the most common cause of which is the presence of pulmonary lesions. Eight cases of aortic graft infection and aortoenteric fistulae in association with HO have been recognized. A case of an infected axillary-axillary graft presenting as unilateral HO of the upper limb is reported, and its unusual features are used to postulate a mechanism underlying HO.  相似文献   
78.
Incidence rates and death rates for acute myocardial infarction (AMI) were compared in New South Wales and Queensland to investigate whether changes in death rates were correlated with changes in incidence rates. The incidence of AMI was 1.9 per cent higher for males and 14.9 per cent lower for females in Queensland than in New South Wales. Differences in age-specific incidence rates paralleled differences in age-specific death rates, suggesting that observed changes in death rates may reflect changes in incidence, rather than case-fatality. Risk factor patterns are broadly similar between the two states, apart from the prevalence of cigarette smoking which, like the incidence of AMI, is higher in males and lower in females in Queensland.  相似文献   
79.
A Ziv  JR Boulet  GB Slap 《Pediatrics》1998,101(6):987-994
BACKGROUND: Adolescents in the United States have been shown to underutilize primary care services and therefore may rely heavily on emergency service. Although several small studies have explored local emergency services for youth, there are no published reports of adolescent utilization of emergency services on a national scale. Furthermore, emergency services data have not been aggregated according to the age subgroups used by the current guidelines for adolescent care. OBJECTIVE: To explore the utilization of emergency departments in the United States by early (11 to 14 years), middle (15 to 17 years), and late (18 to 21 years) adolescent subgroups. DESIGN: Secondary analysis of the emergency department component of the 1994 National Hospital Ambulatory Medical Care Survey. SETTING: Nationally representative sample of 418 emergency departments in the United States. PATIENTS: Approximately 26,547 visits by patients of all ages, representing 93.4 million total visits in 1994 and 14.8 million adolescent visits. OUTCOME MEASURES: Number of visits, health insurance, reasons for visits, urgency of visits, resulting diagnoses, and hospitalization rates. RESULTS: Adolescents accounted for 15.4% of the population and 15.8% of emergency department visits in 1994. Late adolescents were overrepresented in emergency department visits relative to their population proportion (6.8% of visits, 5.3% of population), whereas early adolescents were underrepresented (4.6% of visits, 5.9% of population). Lack of health insurance was more common among 11- to 21-year-olds (26.2%) than either children (13.6%) or adults (22.7%). By ages 18 to 21 years, 40.5% of male visits and 27.6% of female visits were uninsured. Injury-related visits were more common among adolescents (28.6%) than either children (23.1%) or adults (18.2%). Injury was the leading reason for visits among all adolescent age-sex subgroups (36.6% to 42.0% of male visits and 14.1% to 27.2% of female visits) except females aged 18 to 21 years for whom digestive reasons ranked first (18.8%). Injury was the leading diagnosis for all adolescent age-sex subgroups, with peaks at early adolescence of 61.6% for males and 45.8% for females. Across all adolescent age-sex subgroups, 3.1% to 5.3% of visits resulted in hospitalization, and 41.0% to 52.5% of visits were urgent. These rates did not differ from those of children but were lower than those of adults. CONCLUSIONS: Utilization of emergency departments increases and health insurance decreases during adolescence, suggesting that adolescents with inadequate health insurance may rely heavily on emergency departments for their health care needs. Most adolescent visits to emergency departments are not urgent and might be better treated through nonemergency, primary care sites.  相似文献   
80.
Dielectric constant of water at very high temperature and pressure   总被引:2,自引:2,他引:0       下载免费PDF全文
Pertinent statistical mechanical theory is combined with the available measurements of the dielectric constant of water at high temperature and pressure to predict that property at still higher temperature. The dielectric constant is needed in connection with studies of electrolytes such as NaCl/H2O at very high temperature.  相似文献   
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