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The source of pulmonary collateral circulation varies according to the nature, location and duration of the inciting pathological process. Bronchial, intercostal, internal mammary, brachiocephalic and other arteries that arise in the mediastinum from the aorta or its branches are the major source of pulmonary arterial collateral circulation. The bronchial veins and mediastinal veins are interconnected with the azygos, vertebral, mediastinal, and thoracic wall veins. They constitute the major venous pathways of the collateral circulation. Anomalous arteries and veins may be recognized radiologically as the cause of a variety of intrathoracic, extracardiac shunts.  相似文献   
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In neuroblastoma, high levels of mRNA for p14h trkA and p75 LNGFR neurotrophin receptors are predictive of favorable outcome. Their evaluation by Northern blot, however, requires substantial amounts of tissue and this prevents their routine evaluation as well as the possibility for multicenter studies to be easily carried out. In an attempt to overcome these limitations, the feasibility and reliability of determining both neurotrophin receptors on cryostat sections by immunohistochemistry were assessed, and these findings were compared to those obtained from Northern blot analysis. Primary tumor samples from 28 untreated patients at all stages were evaluated by using H10 anti-p140 trkA and ME20.4 anti-p75 LNGFR mAbs. Although weak, positiveimmunostaining was found in 9 of 28 tumors for p140 trkA and in 5 of 28 tumors for p75 LNGFR . As compared to Northern blot, the concordance rate was 79% (22 of 28 cases) for p140 trkA (p < 0.05) and 71% (20 of 28 cases) for p75 LNGFR (p < 0.05). No case negative for Northern blot was found to be positive with immunohistochemistry. Since only high mRNA levels for both receptors have been shown to be clinically relevant, their immunohistochemical detection, although less sensitive than Northern blot, can be just as sufficient and reliable as a prognostic tool, and possibly with a better cost-benefit ratio.  相似文献   
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1.  Naja flava venom heated to 100° C for 15 minutes interferes with intracerebrally inducedBrunhilde andLansing poliomyelitis infection in rhesus monkeys when the blockading agent is administered subcutaneously 24 hours after infection.
2.  It is suggested that this interference mechanism is based on the direct action of the heated venom on motoneurons, as evidenced by histopathologic changes in the spinal cords of normal rhesus monkeys injected subcutaneously with the venom.
3.  Similar histopathologic changes are seen when large doses ofNaja flava toxoid are injected subcutaneously into normal rhesus monkeys.
4.  An attempt has been made to extend the interpretation of the neurotoxoid and neurotoxin interference mechanism in poliomyelitis by correlating enzymatic studies of other workers with cobra venom and with chromatolytic cells refractory to poliomyelitis infection.
1.  Wird dasNaja-flava-Gift durch 15 Minuten auf 100° C erhitzt, dann hemmt es die intracerebral eingebrachteBrunhilde- undLansing-Poliomyelitis-Infektion bei Rhesusaffen, wenn das blockierende Agens 24 Stunden nach der Infektion subkutan zugeführt wird.
2.  Es wird angenommen, daß dieser Hemmungsmechanismus auf der direkten Einwirkung des erhitzten Giftes auf die Motoneurone beruht, was durch histopathologische Veränderungen im Rückenmark normaler Rhesusaffen, denen das Gift subkutan injiziert wurde, bewiesen wird.
3.  Ähnliche histopathologische Veränderungen werden bemerkt, wenn starke Dosen desNaja-flava-Toxoids normalen Rhesusaffen subkutan injiziert werden.
4.  Es wurde der Versuch gemacht, die Erklärung des Neurotoxoid- und Neurotoxin-Hemmungsmechanismus bei der Poliomyelitis durch die Vergleichung enzymatischer Studien anderer Forscher am Kobra-Gift und an chromatolytischen Zellen, die der Poliomyelitis-Infektion Widerstand leisten, zu erweitern.

With 7 Figures.  相似文献   
88.
A Fourier transform infrared spectroscopy/attenuated total reflection technique for direct quantification of adsorbed poly(styrene) latexes on rat intestinal mucosa was developed for deposited latex amounts up to 1.5 g/m2. The method agreed well with another dosage assay of adsorbed particles by turbidimetry after denaturation of the mucus. Adsorption kinetics were made under static conditions at latex concentrations of 4 g/L in physiological saline. Ninety percent of equilibrium was reached after 10 min for a particle size of 230 nm, 20 min for a size of 320 nm, and 30 min for a size of 670 nm. The plateaus were between 0.6 and 0.9 g/m2 (adsorbed mass per apparent surface of mucosa). The first phase of the kinetics was theoretically approached by a diffusion model in the suspension medium. Mucosa from rat jejunum and ileum could be considered as a homogeneous biological model for latex adsorption.  相似文献   
89.
The nervous system of two larval stages (cercariae, metacercariae) of eye flukeDiplostomum spathaceum was investigated immunocytochemically by the application of antisera to the amino acid glutamate and to neuropeptides isolated from invertebrates (Mollusca) and from vertebrates to whole-mount preparations. In cercariae, positive immunoreactivity (IR) was observed with antisera raised against Catch-relaxing peptide (CARP), FMRFamide, -caudodorsal cell peptide (-CDCP), substance P, vasotocin, and vasopressin. In metacercariae, in addition to positive staining with these antisera, the ones raised against glutamate, APGWamide, caudodorsal cell hormone I (CDCH-I), and small cardiac peptide B (SCPB) also gave positive IR in the nervous system. In the two larval stages the most extensive pattern of IR was observed with anti-FMRFamide and anti-CARP. In the nervous system of metacercariae the same immunoreactive neurosubstances appeared to be present as in that of cercariae. The increase in the variety of immunoreactive neurosubstances in the more complex nervous system of metacercariae is discussed in relation to parasite development and to host adaptation.  相似文献   
90.
In recent years, eating disorders (Anorexia and Bulimia Nervosa) have increased and are appearing at increasingly younger ages. They affect predominantly adolescent females 12 to 25 years of age. The objective of this study of adolescents is to detect and discuss unhealthy eating behaviour, defined by either of two factors: (1) following a slimming diet not advised or supervised by any person trained in health care; or (2) eating very large quantities at irregular times, not related to anxiety or stress. A transversal study has been undertaken of 630 school children of 14–18 years of age (average: 15.9 years) in Cádiz (Andalucia, Spain), using an anonymous self-reporting questionnaire to collect data on personal and educational situation, on eating habits, on nutritive intake and knowledge of nutrition, and on dieting and physical exercise. The study has considered averages, ratios, statistical significance (x 2) and, as a measure of risk, the Disequality Ratio of Prevalence (DRP). Anomalous eating behaviour was detected in 46.3% (292), with females predominant by a ratio of 2:1. Comparing groups with anomalous and with normal eating habits, significant differences were detected in respect of: perception of body image (p<0.001), frequency of weighing oneself (p<0.05), periods of abstinence from eating (DRP 1.66; 95% confidence interval (CI): 1.66–2.37), provocation of vomiting (DRP 2.02; 95% CI: 1.13–3.65), use of laxatives (DRP 4.25; 95% CI: 1.08–9.63), and the exclusion of certain meals and types of food, mainly bread and cereals, fats and sugars. Conclusions are drawn on the substantial scale of unhealthy eating behaviour among adolescents in Cadiz. More adequate education on personal health and related social issues should be provided.  相似文献   
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