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21.
Anatomy and pathology of the kidney by gray scale ultrasound   总被引:1,自引:0,他引:1  
  相似文献   
22.
The galactoside-specific plant lectin, Viscum album agglutinin-(VAA)-I has been shown to activate the natural immune system and modulate the maturation of thymocytes in vivo. However the mechanism of this immunobiological action is not yet understood. In our previous study we demonstrated the VAA-I-induced enhancement of proliferation and selection of thymocytes which inhibited the dexamethasone (DX)-induced thymocyte depletion. In this present work we investigated the effect of 1, 4 and 21 days of VAA-I treatment on DX-induced apoptosis of thymocytes in Balb/c mice. The number of early apoptotic cells was detected with Annexin V staining while the late apoptotic cells were identified according to their propidium iodide incorporation into DNA using flow cytometry. The expression of glucocorticoid receptor (GCR) in double-negative (DN), double-positive (DP) and CD4 or CD8 single-positive (SP) cell populations was assessed. The additive effect of lectin on DX-induced apoptosis of thymocytes consisted of two different actions of VAA-I and DX. One-day VAA-I treatment caused enhanced apoptosis in SP mature cells in contrast to the apoptotic effect of DX, which was mainly directed towards immature DN and DP cells. Treatment with 30 ng/kg VAA-I for four days elevated the GCR level (mean fluorescence intensity) in DP thymocytes. Lectin treatment for 21 days caused more than 20% elevation of GCR expression in all thymocyte subpopulations (DN, DP, CD4+ and CD8+). These results suggest that VAA-I may alter the sensitivity of thymocytes to glucocorticoids and this effect may play a role in the bell-shaped dose-response curve of lectin-induced immunological effects.  相似文献   
23.
We determined the relative effects of chemical receptor inactivation on dopaminergic signaling through adenylate cyclase and phospholipase C pathways and evaluated the behavioral implications of such receptor manipulations. Groups of rats were given intraperitoneal injections of 10 mg/kg N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ), a reagent that differentially inactivates neurotransmitter receptors. Control and treated animals were used to assess dopaminergic-mediated behaviors or brain tissues were prepared from the animals and used to assay D1-like receptor binding and agonist-stimulated second messenger formation. EEDQ decreased by 75% the number of D1-like binding sites and completely abolished dopamine-stimulated cyclic AMP formation in striatal membranes. Conversely, dopamine-stimulated phosphoinositide hydrolysis was insensitive to inactivation by EEDQ as examined over different durations of EEDQ treatment, in different brain regions, or with different concentrations of the D1-like receptor agonist SKF38393. EEDQ-pretreated animals lost their stereotypic response to apomorphine but showed increased vacuous jaw movements in response to apomorphine or SKF38393. Basal catalepsy was increased and SCH23390 was unable to further enhance catalepsy beyond the basal levels in the lesioned animals. In naive animals, SCH23390 catalepsy was reversed by apomorphine, and apomorphine stereotypy was reversed by SCH23390. Taken together, the present results imply that the dopamine-sensitive phospholipase C system mediates a subset of dopaminergic behaviors, notably vacuous jaw movements, in contrast to stereotypy and catalepsy which appear to be respectively mediated through stimulation and inhibition of the adenylate cyclase-coupled dopaminergic system.  相似文献   
24.
急性淋巴细胞白血病(上)   总被引:2,自引:0,他引:2  
急性淋巴细胞白血病是淋巴前体细胞异常引起的恶性疾病,儿童与成人均可能发生。儿童发病高峰2~5岁。有效治疗的稳步进展使本病在儿童中的治愈率80%以上,同时为新的治疗方案提供了良机,新方案将保留我们在白血病无病生存病例中获得的治疗经验,同时减轻当前强化治疗方案中的毒副作用。  相似文献   
25.
Percutaneous nephrostolithotomy, which can require a double puncture, is presently the method of choice in our institution for the removal of renal stones. Patients that underwent this procedure were evaluated to identify the possible reasons for the double puncture. Of 200 patients evaluated, 14 needed a second tract. The three variables that determined whether a second puncture was needed, in order of importance, were number and size of the stones, with second tracts needed in patients with multiple stones and staghorn calculi; anatomical variations of the renal collecting system itself, with bifid systems the most significant anatomic variation; and the dexterity of the radiologist in performing the puncture and the ability of the urologist to extract the stone. Second tracts were needed more frequently in patients who presented with stones in both the lower and middle poles of the collecting systems.  相似文献   
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28.
Health insurance coverage of the unemployed   总被引:1,自引:0,他引:1  
Of 1,332 unemployed individuals in the Detroit area interviewed in late 1983, 51% did not have health insurance. Lack of insurance was directly related to length of unemployment. Of those unemployed 3 months or less, 31% had no insurance, as compared with 56% of those unemployed more than 3 years. For the most part, these were not the chronically uninsured: 78% of them were insured when they were employed. Three fourths of those without insurance were not covered by Medicaid either. These findings suggest that during the latest economic recession, the problem of health insurance loss due to losing one's job was more severe than had been assumed by most policymakers.  相似文献   
29.
A 23‐year‐old man with the rare sclerosing bone disorder van Buchem disease presented with progressively worsening headaches that eventually became persistent and associated with papilledema. Increased intracranial pressure was diagnosed, and the patient had a ventriculoperitoneal drain inserted as well as simultaneously receiving treatment with prednisone. Before starting treatment, there was biochemical evidence for increased bone turnover and for steady increases in bone mineral density (BMD) at the spine and total hip despite the patient having reached his peak height of 197 cm at the age of 19 years. Treatment with prednisone for 2 years resulted in biochemical and histologic suppression of bone formation as well as of bone resorption and arrest of further bone accumulation. Our data suggest that glucocorticoids (GCs) may represent an attractive alternative to the high‐risk surgical approaches used in the management of patients with progressive sclerosing bone disorders. Our findings also suggest that whereas sclerostin may not be required for the action of GCs on bone formation, it may well be important for the action of GCs on bone resorption. The exact mechanism by which sclerostin may be involved in the regulation of bone resorption is as yet to be explored. © 2010 American Society for Bone and Mineral Research.  相似文献   
30.

Introduction and Hypothesis  

The extracellular matrix proteins collagen and elastin provide tissue strength and resilience, whereas lysyl oxidase enzymes play a major role in their stabilization. This study examines the expression and tissue localization of lysyl oxidase family proteins in the anterior vaginal wall of premenopausal women with advanced pelvic organ prolapse (POP, n = 15) and asymptomatic controls (n = 11). All women were in the proliferative phase of menstrual cycle.  相似文献   
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