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991.
Structural reorganization of the myocardium is observed in CBA mice under conditions of hypogeomagnetic field (reduction by 105 times). Changes in tissue architectonics manifest themselves in a reduced capillary/cardiomyocyte volume ratio against the background of hemodynamic disturbances. Intracellular disturbances result from impaired regeneration processes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 10, pp. 455–459, October, 1997  相似文献   
992.
Fragestellung: Die Karzinomassoziierte Retinopathie (CAR) stellt ein seltenes paraneoplastisches Syndrom dar, das bislang am h?ufigsten bei kleinzelligen Bronchialkarzinomen beschrieben wurde. Wir berichten über 3 Patientinnen mit CAR in Gegenwart eines Mammakarzinoms bzw. eines Karzinoids der Cervix uteri. Patienten und Methode: Es wurden biomikroskopische, perimetrische, angiographische und elektrophysiologische Befunde erhoben. Au?erdem erfolgte eine Testung der Immunreaktivit?t der Seren an humaner Retina. Ergebnisse: Die Befunde umfa?ten ringf?rmige Gesichtsfelddefekte mit statokinetischer Dissoziation und eine pathologische St?bchen- und Zapfenantwort im ERG. Bei 1 Patientin wurde immunhistochemisch eine Reaktion im Bereich der Photorezeptorinnensegmente, der ?u?eren K?rnerschicht sowie der ?u?eren plexiformen Schicht bei fehlendem Nachweis von Antik?rpern gegen Recoverin gefunden. Diskussion: Neben dem kleinzelligen Bronchialkarzinom k?nnen auch andere Prim?rtumoren mit einer CAR vergesellschaftet sein. Der Nachweis von retinalen Autoantik?rpern unterstützt die Annahme einer tumorinduzierten Immunantwort aufgrund der Expression identischer Epitope durch die Tumorzellen. Dabei kommen offensichtlich verschiedene retinale Proteine als Autoantigene in Betracht.   相似文献   
993.
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995.
Abstract Over the past 15–20 years, research has progressively focused on the mucosal T cell as the central factor in the initiation of physiological or pathological changes, first in the growth and maturation of the early (postnatal) intestine, and second in adult-type enteropathies resulting from sensitivity to either food or pathogen-derived antigens. T cell-mediated events may be measured, for example, in terms of specific immunopathologic patterns of change and injury, such as type 1 (lymphocyte infiltration), type 2 (crypt hyperplasia) and type 3 (flat-destructive), which can be recognized and quantitated microscopically; by determination of lymphocyte reactivity through secretion of interleukin-2 receptors (IL-2R) into plasma or expression by mucosal lymphocytes; by quantitation of lymphocyte subsets emigrating into inflamed tissues by immunoperoxidase-labelled monoclonal antibodies; or by the determination of T cell receptor polymorphisms. Alterations in intestinal growth, structure and function at weaning are likely to be T cell-mediated as they are analogous to the same type 1/2 lesions that reflect modulation of adult mucosal architecture in food and parasite-induced hypersensitivity reactions. Enteropathies associated with HIV infection and T cell deficiency display a milder degree of villous flattening and impaired crypt hyperplasia than that typical of gluten-sensitivity, suggesting a reversion to lesser degrees of mucosal pathology (type 1/2). Clearly more information will accrue; meanwhile the remarks in this brief survey should provide a firm basis whereby clinician and scientist can meet, and together recognize and further dissect the modulatory effect of T lymphocytes on mucosal structure and function.  相似文献   
996.
A series of 8 rat and 16 mouse invasive bladder carcinomas were investigated for the presence of silverstained nucleolar organizer regions (AgNORs) to clarify whether this parameter is applicable to the estimation of their invasive character. With regard to number of AgNORs per cell, neither rat nor mouse carcinomas showed any difference between invasive and noninvasive sites within the same tumor. However, the frequency of cancer cells bearing bizarre dots, irregular in size and shape, was significantly higher at sites of actual invasion. Quantitative data generated using an image analyzer revealed significantly lower values for NOR roundness and significantly larger NOR size in invasive sites than in noninvasive sites in all groups. Double staining for the proliferation marker proliferating cell nuclear antigen (PCNA) and AgNORs was performed on eight rat carcinomas and a close correlation between the two was confirmed. Thus the number of AgNORs in PCNA-positive cells was significantly greater than in PCNA-negative cells. Furthermore, a particularly strong correlation was observed for incidences of PCNA-positive cells and bizarre dots (P<0.01). The quantitative data also demonstrated significant differences in size and shape of dots. It is concluded that AgNORs have diagnostic value for the invasive character of bladder carcinomas.  相似文献   
997.
Peripheral chemoreceptors (carotid bodies) are the main sensing organs for hypoxaemia. During carotid surgery, the carotic body in the bifurcation of the common carotid artery is often involved and damaged or destroyed. Animals lose their ability to adapt to high altitude after experimental denervation of the carotid bodies. The objective of our study was to evaluate the ability of human patients to adapt to moderate altitude after single side carotid surgery. Blood gas analysis at rest at 171 m and after car and cable car transport to 1600 m before and after carotid surgery was performed. Mean(s.d.) paO2 decreased insignificantly from 74.8(3.56) at 171 m altitude to 71.6(2.07) at 1600 m (P = n.s.), means(s.d.) paCO2 decreased significantly from 36.2(2.86) to 31.4(2.7) mmHg (P < 0.05) before carotid surgery. Months after surgery, a significant drop in paO2 occurred after identical passive exposure to moderate altitude: mean(s.d.) paCO2 at 171 m 74.4(3.65) mmHg, at 1600 m 65.8(3.70) mmHg (P < 0.01), paCO2 did not change significantly. Mean(s.d.) paCO2 at 171 m: 36.0(2.35), at 1600 m 36.2(2.86) mmHg (P = n.s.). Although the sample investigated was small, after single side carotid surgery patients seem to lose their ability for satisfactory ventilatory response to acute exposure to moderate altitude. This is of possible alpine medical importance.  相似文献   
998.
Resection of the adrenal glands precludes participation in many immunotherapy protocols for metastatic renal cell carcinoma. We performed radical nephrectomy with adrenalectomy and contralateral partial adrenalectomy, including adrenal vein ligation for a 4 cm. hilar metastasis without perioperative complications or local recurrence after 30 months. Adrenal function, measured by cosyntropin stimulation tests 6 weeks and 10 months postoperatively, was normal. Partial adrenalectomy with preservation of adrenal function is possible.  相似文献   
999.
As most of those experiencing traumatic brain injury tend to be young, disabled survivors will be gradually accruing in each locality as each year passes. How many need continuing care a decade after injury? How many need day care, or need help with finding work, or continuing support for carers? 190 patients who had been admitted to two UK regional neurosurgical units on average some 7 years earlier were followed up. With an average age of 29 years these patients stayed in hospital for an average 33 days. At follow-up 23% were classified as having moderate disability or worse on the Glasgow Outcome Scale, including 7.4% who had died subsequent to discharge. Survivors were given a neuropsychological assessment and a socioeconomic interview. Of the survivors, 17% had failed to make a good recovery, but 36% were failing to occupy their time in a meaningful way. Age over 30 at time of injury, not occupied before injury, and above-average length of stay were some of the predictors for failing to occupy time. Quality of life was severely curtailed for those who could not occupy their time, as was the case for their carers. Appropriate counselling, vocational evaluation and family support in the early years following injury may help to improve quality of life for both the head-injured person and their carers.  相似文献   
1000.
Compliance with inhaled asthma medication in preschool children.   总被引:4,自引:1,他引:3       下载免费PDF全文
N A Gibson  A E Ferguson  T C Aitchison    J Y Paton 《Thorax》1995,50(12):1274-1279
BACKGROUND--Previous studies have shown poor compliance with regular drug therapy in children and adults with asthma. In preschool children the parents supervise and are responsible for drug administration, but little is known of compliance in this group. In addition, there are few data on the patterns of drug use of inhaled prophylactic asthma therapy or of the relation between compliance and symptom control. A study was undertaken to address these issues with the hypothesis that parental supervision would result in good compliance. METHODS--The subjects were 29 asthmatic children aged 15 months to five years already established on inhaled prophylactic medication delivered through a large volume spacer. The prescribed drug regimens varied between subjects. This was an observational study using an electronic inhaler timer device to record the date and time of each actuation of the aerosol canister. Diary cards were used for parallel recording of symptoms and parentally reported compliance with a drug regimen. RESULTS--Variable and generally poor compliance was demonstrated with a median of 50% of study days with full compliance (subject range 0-94%) and an overall median of 77% of prescribed doses of therapy taken during the study period. No relation was found between frequency of prescribed regimen and good compliance. Day care was associated with poorer compliance. No relation between good compliance and low symptom scores was found. CONCLUSION--Compliance with inhaled prophylactic therapy is poor in preschool children with asthma whose medication is administered under parental supervision.  相似文献   
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