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11.
The choriocapillaris in spontaneously diabetic rats. 总被引:1,自引:0,他引:1
During diabetes in rats, the choroid of the eye shows increased permeability to albumin, basement membrane thickening, and decreased anionic charge sites on the abluminal surfaces of the choriocapillary microvessels. In other microvascular beds, permeability differences are correlated with differences in luminal membrane microdomains as indicated by the distribution of luminal membrane anionic charge. To see whether luminal surface charge distribution or other structural features of the choroidal microvasculature become altered during diabetes, we studied spontaneously diabetic and control rats using ultrastructural tracers and morphometric techniques. Rats were injected with horseradish peroxidase and perfused with aldehydes, and then retina-choroid tissue sections were incubated with cationized ferritin, reacted to visualize peroxidase, and prepared for electron microscopic study. The most striking alterations in the diabetic rats were vascular debris and migrating cells resembling vascular cells in the choriocapillaris stroma, suggesting an increase in capillary turnover. In addition, extracellular matrix material was increased, and peroxidase uptake and ferritin binding were low in some vessels of the diabetic rats compared with the controls. Variability was large in the diabetic animals, however, and other vessels remained apparently normal. 相似文献
12.
J L McKimm-Breschkin J B Caldwell R E Guthrie A A Kortt 《Journal of virological methods》1991,32(1):121-124
A rapid new method for the purification of neuraminidase (NA) heads from influenza A virus is described. Virus was pelleted directly from allantoic fluid and was digested with pronase. The cores were removed by centrifugation, redigested and the released NA heads were pooled and concentrated. The NA was separated from all contaminating proteins in a single step on a Superose 12 column. The purified material was suitable for both crystallography and for the production of monospecific antisera. 相似文献
13.
A reduction of natural killer (NK) cell activity has been found in hospitalized patients with major depressive disorder. To examine whether a reduction of NK activity is found in other psychiatric patients or related to the nonspecific effects of hospitalization, NK cell cytotoxicity was compared in hospitalized depressed patients, schizophrenic inpatients, and two groups of controls separately age matched to each patient group. NK activity was significantly (p less than 0.01) lower in depressed inpatients than control subjects. However, in the hospitalized schizophrenic patients values of natural cytotoxicity did not differ from controls. These findings suggest that reduced NK cytotoxicity in depression is independent of the effects of hospitalization. 相似文献
14.
The suction trephine was studied in 31 aphakic and pseudophakic penetrating keratoplasty patients (31 eyes). The postoperative corneal astigmatism averaged 3.9 +/- 2.8 diopters overall. The 15 pseudophakic cases in nonscarred corneas showed a marked reduction in postoperative corneal astigmatism (3.59 diopters) when compared to previous reports. Our results have encouraged us to continue use of the suction trephine in all aphakic or combined keratoplasty procedures. 相似文献
15.
The effect of the immunomodulator, poly rI:rC, upon the in vivo metabolism of [14C]-paracetamol has been investigated in male BALB/cJ mice. In both poly rI:rC treated and control groups of mice the major part of the dose was excreted in the 0-24 hr urine and the major urinary metabolites were the glucuronic acid and sulphate conjugates. The urinary excretion of these two conjugates and of free paracetamol was not significantly altered following poly rI:rC treatment. Following enzymic hydrolysis of glucuronides and sulphates, the 3-cysteine, 3-mercapturate, 3-thiomethyl and 3-methylsulphoxide metabolites of paracetamol were all identified in the 0-24 hr urine together with very small amounts of 3-methoxy paracetamol. Although poly rI:rC treatment reduced the proportional urinary excretion of each of the thio adducts the individual differences were not significant. However, total thio adduct excretion, an indirect estimate of the metabolic activation of paracetamol, was significantly lower following poly rI:rC treatment. This depression in the urinary excretion of thio adducts following poly rI:rC treatment is discussed in relation to possible implications for paracetamol toxicity. 相似文献
16.
J A Caldwell 《Military medicine》1992,157(6):275-281
A brief questionnaire was administered to 148 soldiers, over two-thirds of whom were aviators, at the conclusion of Desert Storm. Questions were asked about chemical defense, work/rest schedules, an aspect of pharmacological support, and heat stress/physical training during Operations Desert Shield and Desert Storm. Follow-up face-to-face interviews also were conducted with some respondents. Some of the most noteworthy findings concerned (1) training issues and side effects related to pyridostigmine bromide, (2) problems with chemical defense clothing, (3) suggestions for improving crew rest, and (4) facts about the ways in which heat-related difficulties were minimized. 相似文献
17.
Functional anatomy and biomechanics of the meniscus 总被引:2,自引:0,他引:2
George L. Caldwell Jr. MD Answorth A. Allen MD Freddie H. Fu MD 《Operative Techniques in Sports Medicine》1994,2(3):152-163
The meniscus is no longer considered the evolutionary remnant in the knee joint.Rather, it is now well established as an important structure that is integral to the complex biomechanics and proper functioning of the knee. The medial and lateral menisci form two crescent-shaped wedges of fibrocartilage between the femoral condyles and tibial plateaus.The knee joint biomechanics are based on a complex interaction of these intra-articular structures. The functions ascribed to the menisci include load transmission, shock absorption, stability, proprioception, joint lubrication, and joint nutrition. Load transmission generally is accepted as one of its primary functions. The menisci transmit a portion of the axial forces across the knee joint by converting this load into “hoop stresses.” This is accomplished by their unique shape, composition, and anatomic attachments. The menisci are relatively mobile structures and their motion during knee flexion also is determined by their shape and soft tissue attachments/constraints. Preservation of the meniscal functions is essential, and the authors review the basic anatomic and biomechanical concepts necessary to understand techniques for repair and restoration of these functions. 相似文献
18.
Incidence of PTSD among staff victims of patient violence. 总被引:2,自引:0,他引:2
M F Caldwell 《Hospital & community psychiatry》1992,43(8):838-839
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