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91.
92.
Angiogenesis precedes recovery following spinal cord injury and its extent correlates with neural regeneration, suggesting that angiogenesis may play a role in repair. An important precondition for studying the role of angiogenesis is the ability to induce it in a controlled manner. Previously, we showed that a coculture of endothelial cells (ECs) and neural progenitor cells (NPCs) promoted the formation of stable tubes in vitro and stable, functional vascular networks in vivo in a subcutaneous model. We sought to test whether a similar coculture would lead to the formation of stable functional vessels in the spinal cord following injury. We created microvascular networks in a biodegradable two-component implant system and tested the ability of the coculture or controls (lesion control, implant alone, implant + ECs or implant + NPCs) to promote angiogenesis in a rat hemisection model of spinal cord injury. The coculture implant led to a fourfold increase in functional vessels compared with the lesion control, implant alone or implant + NPCs groups and a twofold increase in functional vessels over the implant + ECs group. Furthermore, half of the vessels in the coculture implant exhibited positive staining for the endothelial barrier antigen, a marker for the formation of the blood–spinal cord barrier. No other groups have shown positive staining for the blood–spinal cord barrier in the injury epicenter. This work provides a novel method to induce angiogenesis following spinal cord injury and a foundation for studying its role in repair.  相似文献   
93.
In 2 patients with the Jarvik 2000 left ventricular assist device (LVAD), we assessed left ventricular systolic function through pressure-volume loops and E(max) at the beginning and end of the support period to potentially predict the possibility of pump removal without transplantation. Immediately before LVAD implantation and explantation, pressure and volume measurements were made with catheters and echocardiography, respectively, the E(max) being calculated from the slope of the pressure-volume loops, and the left ventricular ejection fraction (LVEF) being estimated by echocardiography. Transplantation was performed after 14 and 62 days, respectively, during which the LVEF increased by 75% (from 12% to 21%) in Patient 1 and remained unchanged (from 16% to 18%) in Patient 2, whereas the E(max) increased from 0.63 and 0.42 mm Hg/ml, respectively, to 1.31 and 1.07 mm Hg/ml, reflecting a 107% and 155% improvement. In these 2 cases, the E(max) was a more reliable indicator of intrinsic myocardial contractility than was the LVEF.  相似文献   
94.

Objective:   

The aim of the present study was to characterise traumatic deaths occurring in the emergency room (ER) and to assess retrospectively the quality of given emergency care by evaluating whether any of the deaths could be identified as potentially preventable.  相似文献   
95.
96.
The development and implementation of effective community support systems are goals of many public mental health authorities who are attempting to shift the focus and dollars for mental health services from inpatient to community care. This article presents the results of a survey which asked 90 community mental health agency case managers to assess the community support and residential needs of over 1400 of their clients. Medication monitoring and therapy were rated high priority needs. Psychosocial treatment, day and vocational activities also ranked high. Survey responses regarding residential services indicated a need for more supported and supervised options.The study reported was a collaborative effort by county and agency staff.  相似文献   
97.
A 46-year-old man presented with shock and adult respiratory distress syndrome. Investigations revealed an adrenal mass that was diagnosed, by fine-needle aspiration biopsy, as pheochromocytoma. Because biopsy is contraindicated in patients with pheochromocytoma, this confusing presentation underscores the value of excluding this diagnosis by biochemical means before performing fine-needle aspiration of adrenal tumours.  相似文献   
98.
To determine the effect of MR imaging on the immune system, 21 male C57BL/6 X DBA/2 F1 mice were exposed to MR imaging at a field strength of 0.15 T for 2 hr. Another nine mice (controls) were sham exposed for the same amount of time. Mice were sacrificed and their spleens removed 24, 72, and 144 hr after the exposure (MR or sham). Spleen cell suspensions were passed over nylon wool columns and then used as effector cells in a short-term natural killer cell cytotoxicity assay with 51Cr-labeled YAC-1 cells as target cells. The results showed no evidence of decreased cytotoxicity due to exposure to MR. On the contrary, at all three times after exposure and for all target-to-effector cell ratios, mean cytotoxicity was greater for MR-exposed groups than for sham-exposed groups. The results show that MR exposure has no adverse effect on the immune system, as evidenced by natural killer cell activity.  相似文献   
99.
On the basis of results of an investigation of the effects of different treatments employed, a dialysed and reduced extract of Cupressus sempervirens was separated electrophoretically on sodium dodecylsulphate-polyacrylamide gels before being transferred and then fixed with glutaraldehyde to nitrocellulose membrane. Probing with sera from 91 subjects allergic to C. sempervirens pollen followed by detection of bound IgE antibodies with [125I]-labelled anti-human IgE revealed 17 IgE-binding proteins in the molecular weight range 14-96 kilodaltons (kDa). One component, of molecular weight approximately 42 kDa, reacted with IgE antibodies in the sera of 81.3% of the allergic subjects and, for each of the subjects, this component bound the greatest quantity of IgE. Almost 50% of the sera recognized only the approximately 42 kDa component, reinforcing the conclusion that this component is the major allergen of C. sempervirens pollen. A comparative study employing C. sempervirens pollen allergen discs prepared commercially or in the laboratory showed that values of the uptakes of [125I]-anti-IgE indicating the presence of pollen-reactive IgE antibodies obtained with the latter discs were consistently higher (means 4.5 vs. 0.88), and that false-negative results were obtained when many sera were used with the commercial discs. The results of this study provide an essential basis for the production of standardized, safe and effective C. sempervirens pollen extract applicable to diagnosis and therapy of cypress pollen allergy.  相似文献   
100.
Free erythrocyte protoporphyrin (FEP) and hemoglobin (Hgb) concentrations were tested in 790 children in a private pediatric office; results were compared to those obtained in 1984. Only 16 children (2%) had abnormal FEPs in 1990 compared to 76 children (9.6%) in the earlier study. The mean FEP in the normal group also decreased significantly in each age group studied. The hemoglobin concentrations were not significantly different in most of the age groups studied. Screening for iron deficiency in our pediatric practice by determining hemoglobin and FEP concentrations had a much lower yield in 1990 than in 1984.  相似文献   
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