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71.
The distribution of tyrosine-hydroxylase (TH)-immunoreactive cell bodies and fibers in the diencephalon has been investigated with immunohistological techniques in the pigeon. The results suggest that TH is present in a number of morphologically distinct neuronal systems. Preoptic and hypothalamic TH neurons were subdivided into a medial periventricular and a lateral group. The medial group starts with a rostral collection of small cells in the preoptic region. A significantly larger collection of TH neurons occupies the paraventricular nucleus (PVN) (stratum cellulare internum) and mainly consists of large multipolar cells. Further caudally, the main concentration of cells is in the hypothalamic posteromedial and the periventricular regions of the tuberoinfundibular (arcuate) nucleus. No TH neuron was found in the ventral and lateral parts of the tuberoinfundibular region, suggesting that the prominent tuberoinfundibular dopaminergic system described in mammals is absent in the pigeon. This further substantiated by the relative scarcity of TH immunoreactive fibers and varicosities in the neurohemal zone of the median eminence (ME). The caudalmost components of the medial group appear to be continuous with the large population of TH neurons distributed in the midline of the mesencephalon. Tyrosine-hydroxylase-immunopositive cells have not been found in the paraventricular organ. The lateral group consists of TH neurons loosely arranged in the lateral hypothalamus, including regions of the supraoptic nucleus and hypothalamic posterolateral nucleus. Tyrosine-hydroxylase containing neurons vary widely in size, shape, and dendritic arborization in each diencephalic region. However, it is possible to distinguish two main cell types. Small bipolar neurons with two simple arborizing dendrites were concentrated in the medial periventricular system. The second type of cell is large, multipolar with four to five branching dendrites. This latter cell type occurs mainly in the lateral system and in the PVN. Major fiber bundles containing TH immunoreactivity were identified in the lateral and periventricular hypothalamus. The paraventricular organ and the organum vasculosum laminae terminalis contained the densest arborization of fibers and varicosities. In the ME, dense innervation was found in the subependymal layer. Dense arborizations of TH positive fibers and varicosities were located in the septal nuclei and the paleostriatum augmentatum.  相似文献   
72.
Topographic electroencephalography was carried out to study reaction to photic stimulation in 29 normal volunteers, and 12 patients who had presented frequent clinically confirmed migraines for at least 3 years. In the group of migraineurs photic stimulation resulted in an increase in the alpha band power. The difference between the two groups was statistically significant. This reaction to photic stimulation is of help in diagnosis and suggests that a diagnosis and therapeutic orientation might be possible in patients for whom clinical diagnosis is not clear. The specificity of the migraineur's reaction to photic stimulation and its possible origin are discussed.  相似文献   
73.
74.
Zusammenfassung Die bogenförmige ST-Strecke kommt häufig, in etwa 12%der Fälle, und die Zwischenzacke selten, in 5der Fälle eines nichtausgewählten Krankenmaterials, vor. Sowohl die Entstehungsursache der bogenförmigen ST-Strecke als der Kischschen Zwischenzacke liegt in der stärkeren oder schwächeren Rechts- oder Linksdeviation der S-Achse. Die Richtung und der Grad der S-Achsendeviation wird es also bestimmen, in wie vielen und welcher Einthovenschen Ableitung die bogenförmige ST-Strecke bzw. die Zwischenzacke notwendigerweise auftreten muß. Bei S-Achsenstellungen zwischen –90°und –30°wird die ST-Strecke in Ableitung I, bei S-Achsenstellungen zwischen –30°und +30°in der I. und II., zwischen +30°und +90°in der I., II., III., zwischen +90°und +150°in der II., III. und bei den Achsenstellungen zwischen +150°und –150°in der III. Einthovenschen Ableitung bogenförmig sein. Die klinische Bedeutung der bogenförmigen ST-Strecke ist gleich mit der klinischen Bedeutung der S-Achsendeviation. Bei dem Vergleich des Herzbefundes der Kranken mit der elektrischen S-Achsenstellung können folgende Feststellungen gemacht werden: Geringergradige Linksdeviation der S-Achse, d. h. bogenförmiges ST I sowie geringergradige Rechtsdeviation der S-Achse, d. h. STIII kann praktisch bei pathologischem Herzbefund nicht verwertet werden. Stärkere Links- bzw. Rechtsdeviation der S-Achse, d. h. STI undII bzw. STII undIII können im allgemeinen ebenfalls nicht verwertet werden, es ist jedoch wahrscheinlich, daß sie schon einen Übergang zu den pathologischen Befunden bilden. Während jene starken S-Achsendeviationen, wo schon in allen drei Ableitungen bogenförmiges ST besteht, meistens für das Zeichen der myokardialen Läsion betrachtet werden sollen, und zwar in erster Linie dann, wenn die positive S-Zacke in oder neben dem absteigenden Schenkel der R-Zacke gut wahrnehmbar ist.  相似文献   
75.
Introduction and objectiveWhen sleep apnea-hypopnea syndrome (SAHS) and cardiovascular disease occur concurrently, prognosis is affected. Echocardiography can detect structural cardiac abnormalities but using this technique in all patients would place a heavy burden on resources. The objective of this study was to investigate whether the N-terminal fraction of brain natriuretic peptide (NT-proBNP) can be used as a marker for silent heart disease.Patients and methodsNT-proBNP concentration was measured in the 114 consecutive patients with SAHS who underwent echocardiography before starting treatment. Left and right ventricular systolic and diastolic function, as well as structural abnormalities, were studied. Correlations between NT-proBNP concentration and the abnormalities detected were investigated. A receiver operating characteristics (ROC) curve was plotted for NT-proBNP concentration and cardiac abnormalities.ResultsData for 98 patients were finally analyzed. NT-proBNP concentration was significantly correlated with ventricular septal thickness (r=0.63), posterior wall thickness (r=0.45), and left ventricular enddiastolic diameter (r=0.51) (P<.0001 for all correlations). The area under the ROC curve was significant (0.870; 95% confidence interval, 0.801-0.939; P<.0001). Assuming that specificity would be more useful for clinical practice, we calculated that NT-proBNP concentrations below 100 and 200 pg/mL could rule out structural abnormalities with a reliability of 90% and 100%, respectively.ConclusionsNT-proBNP concentration was strongly correlated with echocardiographic abnormalities and so could be a useful tool for identifying patients who should be referred to the cardiologist.  相似文献   
76.
Surgical procedures for the mammary region currently are assuming an important role in body-contouring surgery. Enhancement of results is a constant challenge to the plastic surgeon. A simple and efficient maneuver for resection of the breast’s lateral pole based on the mammoplasty technique of Professor Ivo Pitanguy is described. This study realized at the Private Clinic Sérgio Carreir?o, Rio de Janeiro, RJ, Brazil.  相似文献   
77.
Abstract  Upper gastrointestinal (GI) symptoms occur frequently in the general population, making them among the most common indications responsible for patients consulting the healthcare system. Consequently, understanding and characterization of the upper GI symptoms is important for the diagnosis and assessment of organ dysfunction. In practice, assessment of clinical symptoms is difficult and it is still to a large extent unclear how sensitivity, volume and tone contribute to visceral perception in the upper GI tract. The goal of advanced research in upper GI symptoms is to obtain a better understanding of the mechanisms involved in transduction, transmission, and perception under normal and pathophysiological conditions. An important step towards this goal is understanding the information provided by and the inherent limitations of the currently available measuring techniques. This article focuses on the sensory testing of the oesophagus, and methods and concepts used to assess the relation between gastric volumes or tone and upper GI symptoms. It also summarizes the contributions of these techniques towards identifying the components responsible for the generation of upper GI symptoms.  相似文献   
78.
BACKGROUND: Clinical benefit from extended lymphadenectomy for gastric cancer remains controversial as a considerable variation exists between results of different studies. METHODS: 562 patients were treated at HUCH between 1987-2003, whereof 223 underwent gastrectomy with curative intent. Of these, 114 patients underwent subtotal/total gastrectomy with D1 (standard) lymphadenectomy and 109 patients had D2-3 (extended) lymph node dissection. The clinical outcome of these patients was analysed retrospectively. RESULTS: The incidence of surgical complications was 33.0% in D2-3 and 16.8% in D1 lymphadenectomy groups (p = 0.008). Abscess was the most common complication (11.0%) among D2-3 operated patients and haemorrhage (4.4%) in D1 group. Hospital mortality was 3.7% in D2-3 and 1.8% in D1 group (p = 0.438). The only statistically significant factor influencing the rate of complications was D2-3 lymphadenectomy (OR 2.620, 95% C.I. 1.375 to 4.991). D2-3 was associated with a longer postoperative hospital stay and operation time, greater blood loss and increased need for blood transfusions compared to D1. The 5-year survival was not statistically different between lymphadenectomy groups. CONCLUSION: It is justified to perform a D2-3 gastrectomy in Europe with a acceptable postoperative mortality but with a significant morbidity. Further studies are needed to assess the value of extended lymphadenectomy in gastric cancer.  相似文献   
79.
Five patients with idiopathic transient osteoporosis were examined. Bone scanning and MRI was helpful in the diagnosis to differentiate of necrosis and all patients recovered completely with conservative and symptomatic treatment. There was no history of trauma in all patients. MRI was realized previously in all cases to confirm the diagnosis and after the resolution of symptomathology.  相似文献   
80.
Coinciding with the present period of unemployment, a corps of school assistants – assistants de vie scolaire (AVS) – has been created in order to meet the demand for in-school assistance raised by the development of schooling for children with special needs. This paper reports on a questionnaire-based survey carried out among 151 AVS working in the Seine Saint-Denis department. It aims at describing their working conditions considering the precariousness of their status (temporary jobs, poor pay) and the nature of their assignment. The main question bears on whether these conditions enable the assistants to develop the capabilities necessary for dealing with their tasks. Results could contribute to the present issue of reorienting government action in order to improve these jobs in terms of professional development. Notably, they reveal that AVS's training is usually brief and that their opportunities for developing workplace professional relationships are scant even though these are needed for them to collaborate with the other workers concerned by schooling children with special needs.  相似文献   
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