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101.
102.
To produce hybrids, one member of the parental line is genetically made male-sterile. This male-sterile trait is encoded by mitochondria so that it is maternally inherited. Consequently, the progeny of a male-sterile plant is fully sterile. Nevertheless, during the handling of cytoplasmic male-sterile seed stocks, some mixture with seeds of the maintainer lines can occur. Up to the present time, the only way to check the homogeneity of the cytoplasmic male-sterile seed stock was to grow the plants until flowering time. We have developed a method which can be used immediately after the harvest, allowing us to check samples from both sunflower and sugar beet. We used the mitochondrial plasmid, present only in the maintainer lines, as a probe for the total nucleic acids prepared from the cytoplasmic male-sterile seed stocks which might be contaminated. The signals compared to those of samples artificially contaminated allow us to measure as few as one male-fertile seed in 1000 seeds in a rapid and accurate manner.  相似文献   
103.
A detailed examination of quantitative relationships of pharmacological action with plasma and tissue concentrations of indomethacin has been undertaken in the rat, after single oral administration of two sustained release preparations. In this study, drug was assayed by high performance liquid chromatography, whereas antiinflammatory response was assessed through the carrageenin-induced edema test. Significant linear correlations (p less than 0.001) were found between logarithmically transformed percent inhibition of edema and logarithmically transformed plasma, as well as tissue levels of indomethacin. However, the lack of significance for partial correlation regarding tissue concentration, contrary to plasma concentration, suggests that pharmacological response is more closely related to the latter, indicating that antidematous effect is mediated via the circulating drug rather than a local action in target tissues. This assumption is further discussed from the equivalence point of view. The relevance of this type of study in the case of topical administration of indomethacin is addressed as well. Taking into account the predictive value of the rat paw edema test for clinical efficacy, relationships similar to those observed are to be expected in man. The high correlation existing between plasma concentration of indomethacin and its pharmacological effect justifies the development and use of sustained release preparations in order to improve the outcome of treatment with this nonsteroidal antiinflammatory drug.  相似文献   
104.
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   
105.
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   
106.
107.
Gastrogastric fistula: a possible complication of Roux-en-Y gastric bypass.   总被引:4,自引:0,他引:4  
BACKGROUND: Gastrogastric fistula is a communication between the proximal gastric pouch and the distal gastric remnant, rarely described in the realm of bariatric procedures. The aim of this study was to review the existing literature about this topic and to demonstrate its laparoscopic treatment. METHODS: An extensive literature review found several articles reporting this complication. However, no citation was found describing the steps of the laparoscopic management of this situation. RESULTS: Gastrogastric fistula occurs in up to 6% of Roux-en-Y gastric bypasses. Two theories exist for fistula formation: (1) it is a technical complication derived from the incomplete division of the stomach during the creation of the pouch, and (2) it occurs after a staple-line failure, developing a leak with an abscess, which then drains into the distal stomach forming the fistula. Early symptoms include fever, tachycardia, and abdominal pain. Failure in weight loss is a late clinical sign observed in these patients. Diagnosis is based on radiologic study, upper endoscopy and computed tomography. When identified in the acute postoperative course, laparoscopic treatment is easy. Chronic fistulas are difficult to manage, and the laparoscopic approach is an alternative to open surgery. CONCLUSIONS: Gastrogastric fistula is a possible complication of Roux-en-Y gastric bypass and its laparoscopic treatment is feasible.  相似文献   
108.
In brain regions containing noradrenergic (NA) cell bodies or terminals, DSP-4 induces changes in the activity of catecholamine-synthesizing enzymes which suggest that central NA neurons are lesioned by this neurotoxin. In contrast, the lack of change in the same enzymatic activities in an area containing mostly adrenergic (A) neurons (C2 region), favors the hypothesis of a resistance of the A neurons to DSP-4. Furthermore, the enzymatic changes observed in peripheral organs suggest a peripheral activation of the NA cell bodies in response to lesioning of the sympathetic terminals by DSP-4.  相似文献   
109.

Introduction  

Planning human resources for health (HRH) is a complex process for policy-makers and, as a result, many countries worldwide swing from surplus to shortage. In-depth case studies can help appraising the challenges encountered and the solutions implemented. This paper has two objectives: to identify the key challenges in HRH planning in Belgium and to formulate recommendations for an effective HRH planning, on the basis of the Belgian case study and lessons drawn from an international benchmarking.  相似文献   
110.
Hypoxia is related to poor prognosis because it is associated to chemo-and radioresistance. During recent years the evolution of imaging methods like PET/CT and MRI has meant the appearance of new perspectives with direct implications in radiation therapy. We discuss previous experiences in staging, planning and in the follow-up process with these techniques for measuring tumour hypoxia.  相似文献   
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