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1.
Circulating prolactin (PRL) levels, dopamine (DA) content, in vitro basal and stimulus-evoked endogenous DA release from arcuate-periventricular nuclei median-eminence fragments were studied in young (4 months) and old (24-25 months) male rats of Sprague-Dawley strain. Serum PRL levels did not differ in young and aged animals. In addition DA tissue content, basal and K+- or d-amphetamine evoked endogenous DA release did not show age-related differences. These results suggest that in male rats of the Sprague-Dawley strain the activity of tuberoinfundibular dopaminergic (TIDA) neurons does not change during senescence, unlike what happens in other strains of rats.  相似文献   
2.
The course of leukemic disease in a male adolescent with meningeal leukemia is described. The bone marrow aspirates showed a conversion from an acute lymphatic leukemia to an eosinophilic leukemia. Four weeks after the peripheral shift of phenotype two different cell clones were detected in one CSF smear. While under ultrahigh dose araC therapy the patient died 3 months after conversion. Possible explanation for the shift of phenotype and the peculiar leptomeningeal infiltration are discussed.  相似文献   
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The Chiquitano-tribe lives in the southern Amazonas region in Bolivia, remote from larger towns. A study (n=1514) on morbidity over an one year period (April 1995 till March 1996) and its relation to general and social medicine is given. Most frequently, childreh under 15 years and women in parity age (15–45 years) sought consultation (34,1 %, 42,7 %). Gastrointestinal, respiratoral and gynecological-obstetric diseases were predominant (22,4 %, 16,2 % and 15,7 %). In the dry season, common colds and respiratoral infections represented the major health problem. In the rainy season, infectious diarrhea diseases caused by polluted water as a consequence of extended floods were most frequent. Typical tropical diseases (malaria, Dengue fever, Chagas’ disease, leprosy a.o.) and socially caused diseases (AIDS, dependencies on drugs and alcohol, consequencies of crime) were rarely seen. With respect to severity, 55,8 % of the patients showed mild disorders. More serious diseases were observed in 39, 8 %. 4,6 % of the patients were diagnosed severly ill and needed hospitalization. Epidemiological data on general and social medicine of minorities in developing countries and their actual degree of medical care are important in a shrinking world. The data are useful to estimate medical needs and plan improvements to the health care system especially in rural areas.  相似文献   
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The lactic acid bacteria: a literature survey   总被引:1,自引:0,他引:1  
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7.
The endometrium is a highly regenerative tissue that plays a crucial role in implantation. We examined the clonal constitution of glandular cells as well as the luminal epithelium of this unique tissue. Using collagenase-based digestion techniques with microscopic manipulation, we isolated individual human endometrial glands and examined their clonality using a polymerase chain reaction-based assay for nonrandom X chromosome inactivation with an X-linked androgen receptor gene. Most of the glands analyzed were composed of monoclonal populations of epithelial cells and one of the glands exhibited a loss of heterogeneity in the androgen receptor gene. In addition, adjacent glands within a 1-mm(2) area shared clonality, suggesting that clonality of the luminal epithelium is regionally defined. The clonality of endometrium was further confirmed in a study of female mice that harbor the green fluorescent protein gene on either the maternal or paternal X chromosome. Fluorescent microscopy of uterine sections revealed that individual endometrial glands consisted completely of either fluorescent or nonfluorescent cells and that the surface epithelium exhibited a clear boundary between these cell types. These findings suggest that single or multiple stem cells with uniform clonality exist on the bottom of each endometrial gland and genetic alterations occurring in such cells may play a critical role in endometrial carcinogenesis. The possible association between area-specific X inactivation of the endometrial surface and the endometrial receptivity of embryo implantation remains to be clarified.  相似文献   
8.
Two adults with mild dementia and a history of memory loss and disequilibrium were seen in the eye clinic following complaints of acuity loss in the 20/30–20/70 (Snellen) range. Results from the fundus examination of one patient were entirely normal; the other showed minimal vascular attenuation and optic atrophy. Electrophysiology was remarkable: (1) Photopic ERG b-waves were reduced, delayed, and showed pronounced oscillations. (2) EOG light-rise potentials were absent or very small. (3) Binocular pattern-VER signals showed addition of the monocular signal. Scotopic ERG signals were normal. Brain biopsy and microscopy showed intercellular, autofluorescent ceroid deposits which provided a clear diagnosis of Kufs disease. Histology of model animal retinal cells show ceroid deposits in cell classes implicated by the human retinal signals. The cluster of electrophysiological results point toward early changes in the pigment epithelium and inner plexiform layer cells as a means of non-invasive diagnosis.  相似文献   
9.
Maida AJ 《Hospital progress》1980,61(4):66-8, 80, 84
Fr. Maida refutes McGrath's Thesis and posits that Catholic health care facilities face special corporate, financial, and theological administrative issues. By maintaining corporate control of the institutions they sponsor, religious congregations can determine institutional policies consistent with church teachings.  相似文献   
10.
Summary Cyclic adenosine 3,5monophosphate (cAMP) was assayed in CSF and plasma obtained from patients with multiple sclerosis. Decreased CSF cAMP levels were found in more than half of the patients while plasma cAMP was normal. The decrease is correlated significantly with the disability of the patient and with the progression of the disease. A low CSF cAMP level can be considered as prognostically unfavorable, particularly in the early stage of the disease. There was no correlation between the cAMP levels and the duration of the disease or with bouts and remissions. ACTH therapy did not normalize the decreased values. Obviously the decrease of CSF cAMP is related to the demyelination and not to the intensity of the pathological immunoreactions.
Zusammenfassung Es wurde das cyclische Adenosin-3,5monophosphat im Liquor von Patienten mit multipler Sklerose untersucht. Bei einem Teil der Patienten wurden auch die Vergleichswerte im Blutplasma bestimmt. Es zeigte sich bei mehr als der Hälfte der Patienten eine Verminderung der cAMP-Konzentration im Liquor bei normalem Plasmaspiegel. Diese cAMP-Verminderung erwies sich als signifikant abhängig von dem Schweregrad der Erkrankung bzw. der Erkrankungsprogredienz und ist besonders in frühen Erkrankungsfällen als prognostisch ungünstiges Zeichen anzusehen. Es fand sich kein Zusammenhang mit dem Krankheitsstadium, d.h. Schub bzw. Intervall, und mit der Erkrankungsdauer. Eine ACTH-Behandlung vermochte diese Verminderung der Werte nicht auszugleichen. Es wird die Wertigkeit dieser Befunde diskutiert.
  相似文献   
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