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1.
Kaposi's sarcoma. CT-radiographic correlation 总被引:1,自引:0,他引:1
The role of CT in the diagnosis of intrathoracic Kaposi's sarcoma (KS) was evaluated retrospectively in 24 patients, in the absence of coexistent opportunistic infections. In all cases the diagnosis of KS was initially established by histologic evaluation of extrathoracic disease: 15 patients had verified parenchymal KS and nine patients endobronchial KS. (Chest roentgenograms were analyzed separately for each group: in 14 patients serial films were available for review. The predominant radiographic findings was the presence of nonspecific, bilateral, perihilar infiltrates in 22 of 24 cases (92 percent). Corresponding CT scans documented the presence of abnormal hilar densities characteristically extending into the adjacent pulmonary parenchyma along distinctly perivascular and peribronchial pathways. Discrete, poorly marginated nodules were identified radiographically in ten cases (42 percent); these proved to be randomly distributed throughout the parenchyma on CT. Radiographic evidence of mediastinal adenopathy was distinctly unusual, seen in only two cases (8 percent). While CT typically demonstrated shotty adenopathy, significantly enlarged nodes (greater than 1 cm) were rarely identified. We concluded that CT is more specific than routine roentgenograms for identifying pulmonary KS. While not pathognomonic, peribronchial and perivascular disease is sufficiently characteristic to obviate more invasive diagnostic procedures, especially in patients with established KS. 相似文献
2.
3.
Dendritic plasticity in the adult neocortex. 总被引:2,自引:0,他引:2
Dendrites are a major determinant of how neurons integrate and process incoming information, and thus, they play a vital role in the functional properties of neural circuits. During the past 30 years, it has become clear that the functional organization of the adult neocortex (and other parts of the brain) is dynamic and can change in response to experimental manipulations that affect cortical activity patterns. A variety of changes in the cortical microcircuit, including changes in synaptic function, neuronal membrane properties, and axonal trajectories, are associated with these functional changes. In this review, the authors discuss changes in the structure of dendrites in the adult neocortex, the sorts of experimental manipulations that induce these changes, and some possible molecular mechanisms that may underlie the changes. 相似文献
4.
The authors made an analysis of the surgical methods in 94 cases of retinal detachment. In 36 cases it was a cerclage, in 44 an episcleral implant. In 8 patients invagination of the sclera was performed, in 3 photocoagulation as a separate intervention and in 3--cerclage with a simultaneous episcleral implant. Reattachment of the retina was achieved in 69.1% of cases. 相似文献
5.
The platelet membrane glycoprotein IIb-IIIa complex is essential for platelet aggregation and functions as a fibrinogen receptor on the activated platelet. When incorporated into phospholipid vesicles, this glycoprotein complex can function as an apparent calcium channel which facilitates the transit of calcium across a phospholipid barrier. In order to further evaluate this calcium channel, the effect of calcium channel blockers of the dihydropyridine (nifedipine and nicardipine), arylalkylamine (verapamil) and benzothiazepine (diltiazem) classes were evaluated on GPIIb-IIIa liposomes with encapsulated fura-2 (a fluorescent calcium indicator). Nicardipine, verapamil, and nifedipine significantly inhibited calcium influx into GPIIb-IIIa liposomes; however, this required 190 microM, 400 microM, and 140 microM drug, respectively. These concentrations are 10-1,000 fold greater than those clinically obtainable. In contrast, diltiazem at concentrations greater than 220 microM and amiloride at concentrations greater than 800 microM showed no inhibitory effects. When aspirinized platelets were activated with 30 micrograms/ml bovine fibrillar collagen, both nicardipine and diltiazem produced a decrease in both the initial rise and maximum cytoplasmic calcium concentration. Parallel experiments were performed to assess the effects of verapamil, nicardipine, and diltiazem on platelet aggregation in platelet rich plasma. Nicardipine, 190-380 microM, induced a prolongation of the lag phase, but no effect on the final degree of platelet aggregation to collagen. Similar inhibition of platelet aggregation was seen with diltiazem and verapamil although the effect of diltiazem was less pronounced particularly at higher concentrations of collagen. No effect was seen on aggregation with 32 microM ADP which is release independent, or on the primary wave of low dose ADP induced platelet aggregation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
6.
Monica J. Carson Tina V. Bilousova Shweta S. Puntambekar Benoit Melchior Jonathan M. Doose Iryna M. Ethell 《Neurotherapeutics》2007,4(4):571-579
Microglial activation and macrophage infiltration into the CNS are common features of CNS autoimmune disease and of chronic
neurodegenerative diseases. Because these cells largely express an overlapping set of common macrophage markers, it has been
difficult to separate their respective contributions to disease onset and progression. This problem is further confounded
by the many types of macrophages that have been termed microglia. Several approaches, ranging from molecular profiling of
isolated cells to the generation of irradiation chimeric rodent models, are now beginning to generate rudimentary definitions
distinguishing the various types of microglia and macrophages found within the CNS and the potential roles that these cells
may play in health and disease. 相似文献
7.
Modelling spinal circuitry involved in locomotor pattern generation: insights from deletions during fictive locomotion 总被引:3,自引:3,他引:3
Ilya A. Rybak Natalia A. Shevtsova Myriam Lafreniere-Roula David A. McCrea 《The Journal of physiology》2006,577(2):617-639
The mammalian spinal cord contains a locomotor central pattern generator (CPG) that can produce alternating rhythmic activity of flexor and extensor motoneurones in the absence of rhythmic input and proprioceptive feedback. During such fictive locomotor activity in decerebrate cats, spontaneous omissions of activity occur simultaneously in multiple agonist motoneurone pools for a number of cycles. During these 'deletions', antagonist motoneurone pools usually become tonically active but may also continue to be rhythmic. The rhythmic activity that re-emerges following a deletion is often not phase shifted. This suggests that some neuronal mechanism can maintain the locomotor period when motoneurone activity fails. To account for these observations, a simplified computational model of the spinal circuitry has been developed in which the locomotor CPG consists of two levels: a half-centre rhythm generator (RG) and a pattern formation (PF) network, with reciprocal inhibitory interactions between antagonist neural populations at each level. The model represents a network of interacting neural populations with single interneurones and motoneurones described in the Hodgkin-Huxley style. The model reproduces the range of locomotor periods and phase durations observed during real locomotion in adult cats and permits independent control of the level of motoneurone activity and of step cycle timing. By altering the excitability of neural populations within the PF network, the model can reproduce deletions in which motoneurone activity fails but the phase of locomotor oscillations is maintained. The model also suggests criteria for the functional identification of spinal interneurones involved in the mammalian locomotor pattern generation. 相似文献
8.
Czarniak E Samet A Bronk M Rybak B Kochowska-Bronk M Zajac-Lenczewska I Ksiazek J Skokowski J 《Pneumonologia i alergologia polska》2003,71(1-2):31-35
The clinical specimens received from patients hospitalized in Department of Thoracic Surgery between 1997 and 2001 were microbiologically examined. The main specimen for microbiological examination was pleural fluid (median 34%). The frequency of specimens from bronchial tree increased significantly (from 4% to 26%) with concurrent decrease of sputum (from 29% to 6%). Among isolated pathogens, Gram negative rods were the most frequent (median 48%) and Pseudomonas sp. was the main pathogen among them. Occurrence of staphylococci was median 22% and Staphylococcus aureus, with a little decrease in analyzed period, was still the main Gram positive pathogen. Simultaneously the occurrence of MRSA in the last three years dropped three times. The number of isolations of yeasts have risen from 5.8% to 10.3%. 相似文献
9.
Hagan MM Wauford PK Chandler PC Jarrett LA Rybak RJ Blackburn K 《Physiology & behavior》2002,77(1):45-54
Dieting and stress are important in the etiology and maintenance of eating disorders, and dieting strongly predicts stress-induced overeating in humans. We hypothesized that caloric restriction and stress interact in a unique manner to promote binge eating. To test this hypothesis, a group of young female rats were cycled through a restriction period (4 days of 66% of control food intake) followed by 6 days of free feeding prior to being stressed by acute foot shock. After three of these cycles, the food intake of rats exposed only to restriction (R), or only to stress (S), did not differ from controls. However, R+S rats that were restricted and refed, despite normal body weight and food intake after free feeding, engaged in a powerful bout of hyperphagia when stressed (Experiment 1). The R + S effect was replicated in an older group of rats (Experiment 2). The hyperphagia was characteristically binge-like, it constituted a 40% selective increase in highly palatable (HP) food (P < .001) over a discrete period of time (within 24 h post-stress), and reflected feeding for reward (higher HP:chow ratio) over metabolic need as occurred after restriction (higher chow:HP ratio). Subsequent experiments revealed that binge eating did not occur if only chow was available (Experiment 3) or if restriction-refeeding (R-R) did not proximally precede stress (Experiment 4). Experiment 5 revealed that a history of R-R cycles followed by only one stress episode was sufficient to increase intake to 53% above controls as early as 2 h after stress (P < .001). This animal model of binge eating should facilitate investigations into the neurochemical changes induced by dieting and environmental stress to produce disordered eating and provide a preclinical tool to test preventive strategies and treatments more relevant to bulimia nervosa, multiple cases of binge eating disorder (BED) and binge-purge type anorexia nervosa. 相似文献
10.
Victoria Flavian Gowele Joyce Kinabo Theresia Jumbe Constance Rybak Wolfgang Stuetz 《Nutrients》2021,13(5)
Inadequate macro- and micronutrient nutrition and its consequences, such as anaemia, iron and vitamin deficiency, and growth retardation, could particularly affect children of small-scale farmers. In the present cross-sectional study, 666 school children aged 5–10 years from villages of Chamwino and Kilosa districts were studied for associations between nutritional and micronutrient status and dietary intake. The overall prevalence of stunting, underweight, and overweight was 28.1, 14.4, and 5%, while that of anaemia and deficiency of iron (ID), vitamin A (VAD), and zinc (ZnD) was 42.9, 29.3, 24.9, and 26.4%, respectively. Dietary recalls (24h) revealed that, except of iron (74%), only small proportions of children reached the recommended daily micronutrient intakes: 4% for zinc, 19% for vitamin A, and 14–46% for B vitamins. Stunting was highly associated with wasting in both districts and with VAD in Chamwino. Anaemia was predicted by ID, VAD, and ZnD in Chamwino and by elevated infection markers, C-reactive protein (CRP) and α-1 glycoprotein (AGP), in Kilosa. Overall, elevated CRP and/or AGP increased the risk while higher serum carotenoids indicating a diet of more fruit and vegetables reduced the risk of VAD. The significantly lower prevalence of anaemia and ID in Chamwino was related to higher iron and vitamin A intake and the consumption of mainly bulrush millet with dark green leafy vegetables compared to maize or rice with legumes in Kilosa. Nutrition and hygiene education integrated with home and school garden programmes could reduce the multiple burdens of anaemia; micronutrient deficiencies and infections; and, in the long term, the prevalence of stunting. 相似文献