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971.
Controversy exists regarding the influence of aging on thyroid hormone metabolism. Several investigators report lowering of T3 and/or a rise in reverse T3 (rT3) in elderly subjects. Others suggest that these thyroid hormone alterations were secondary to associated disorders rather than old age, and questioned the "healthy" status of the subjects studied in the earlier reports. Therefore, to assess the possible effect of aging we studied T3 resin uptake, T4, free T4, T3, and rT3 concentrations in 152 euthyroid healthy adult subjects. These subjects were selected carefully and were therefore devoid of any illness, acute or chronic, and were not treated with any medications at the time of study. No significant alterations were noted in any of the thyroid hormone concentrations in subjects divided into groups according to age. Nor was there a significant difference in these parameters between men and women of any individual age group or for all ages combined. Therefore, old age per se may not influence thyroid hormone metabolism and hence may not induce changes in serum thyroid hormone concentrations. The changes in thyroid hormones noted previously in elderly subjects may be a reflection of concurrent disorders and not old age. 相似文献
972.
U Mandel H Clausen P Vedtofte H S?rensen E Dabelsteen 《Journal of oral pathology》1988,17(9-10):506-511
Cell surface carbohydrates are excellent markers for cellular differentiation and maturation due to great structural and antigenic diversity and to known precursor/product relations. Several blood group related carbohydrate antigens were analyzed in human labial stratified non-keratinized epithelium from 16 healthy individuals by immunohistology using monoclonal antibodies. The expression of these antigens was correlated with erythrocyte phenotype and saliva secretor status. Three distinct compartments of the epithelium were found and defined by the sequential expression of derivatives of Type 2 chain structures: lower, confined to basal cell layers (N-acetyllactosamine), middle, to parabasal cell layers (H) and upper, to spinous cell layers (Le(y)/Le(x)). Although the antigens are related to blood group antigens they are largely expressed independently of the ABO, Lewis and secretor types, and may therefore serve as "universal" markers in differentiation studies of normal and pathological epithelium. 相似文献
973.
E. Haglind U. Haglund H. Haljamäe 《Zeitschrift für die gesamte experimentelle Medizin einschliesslich experimenteller Chirurgie》1988,188(3):197-207
The liver metabolic response of rats following a standardized intestinal shock, induced by applying a pressure of 120 cm water on the mesenteric vessels for 60 min, was studied. Immediately prior to the release of the pressure on the vessels saline or naloxone was given either as a single injection or as a continuous infusion. After the reperfusion of the intestine no early disturbances in liver metabolism were found as evidenced from the ATP, glucose and lactate levels in liver biopsies taken 15 min following reflow. Within 60 min of reflow reduction of ATP and increases of glucose and lactate levels occurred. There were no major hemodynamic or liver metabolic differences between saline- and naloxone-treated shocked rats. When saline or naloxone was given as a continuous infusion, the changes in liver metabolism were, however, less severe than those observed in the single injection situation pointing toward a non-specific effect of volume replacement rather than a blockade of opioid receptors. Hepatic hypoxia and/or cellular effects of "shock factors" could be mechanisms of pathophysiologic importance for the disturbed liver metabolism in this shock model. 相似文献
974.
U Peek 《Archiv fuer geschwulstforschung》1988,58(4):275-285
The so-called "inflammatory" cancer represents a rare but fatal malignancy of the female breast, due to rapid growth and early dissemination. The traditional therapeutic approach, locoregional treatment at first, largely irradiation, but chemotherapy in disseminated disease only, results in a poor outcome: in our experience, all patients died within two years. Compared to it, reversal of treatment modalities, i.e. beginning with an aggressive mode of polychemotherapy, locoregional treatment postponed, does prolong disease-free and overall survival. The locoregional treatment consisted in our series in surgical procedures, predominantly extended radical mastectomy. The reason for this approach was twofold: a) no need to discontinue chemotherapy administration b) Involvement of internal mammary nodes (70%) 8/20 patients, treated 1979-1981, survive 60 months or more No advantage has been seen so far in cases with supraclavicular and/or disease beyond the involved breast. The traditional approach will be justified. 相似文献
975.
In 15 cases of 350 consecutive coronary angioplasties conventional low profile balloon catheters did not traverse the stenosis or occlusion over the guide-wire. A balloon on a wire device ("Microprobe", 2 mm) passed the stenosis or occlusion easily with a good primary result in 14 cases. The angioplasty procedure could then be completed with a larger standard balloon catheter. Use of the balloon on a wire device expands the technical facilities of angioplasty and increases the primary success rate in technically difficult cases. 相似文献
976.
G. V. Peersman F. L. Van de Vyver J. E. Lohman U. Lübke J. Gheuens E. Bellon A. Connelly J. J. Martin 《Acta neuropathologica》1988,76(6):628-632
Summary Chronic recurrent experimental allergic encephalomyelitis was induced in a strain 13 guinea pig by inoculation of isologous spinal cord homogenate. The spinal cord was obtained after perfusion with 4% paraformaldehyde and examined with nuclear magnetic resonance (NMR) imaging. Proton NMR spin echo images (repetition time: 3 s; echo times: 20 and 60 ms) were obtained from intact, isolated spinal cord in a 4.7 Tesla, 50 mm bore magnet. The slice thickness of the images was 380 m and the inplane resolution was 40×40 m. The images showed superficial areas of low signal intensity in the lateroventral regions of the white matter, in some instances with a seam of higher signal intensity. Neuropathologically, these abnormalities corresponded exactly to areas of demyelination. Control images did not show these abnormalities. The present high resolution imaging allowed a correlation between demyelination and abnormal NMR signals in a small laboratory animal with an inflammatory demyelinating disease.Supported by the Belgian Foundation of Medical Scientific Research (FGWO, grant 3.0096.86 and grant 3.0019.86), by the Institute for the promotion of Scientific Research in Industry and Agriculture (IWONL) and by the Scientic Research Planning Office of the Belgian Government (DPWB), contract no. 87/92-120 相似文献
977.
M De Negri M Cremonte E Veneselli R Gaggero E Zanotto U Sannita A Molinari 《Brain & development》1988,10(6):375-381
Secondary generalized epilepsy in childhood, characterized by absences or minor motor seizures, occurs in the forms of various syndromes, as defined by current classifications. EEG often shows continuous or subcontinuous paroxysmal activity associated with partly reversible psychomotor or mental regression. The paroxysmal activity can exhibit one of two distinct patterns: "organized" or "disorganized," although intermediate forms are common. The two patterns differ not only morphologically but also in the responsiveness to drug or hormone therapy, reactivity to stimuli, sleep changes and frequency of disordered slow rhythms. These features are illustrated by means of a survey of 10 cases. 相似文献
978.
Somatosensory evoked potentials following nerve and segmental stimulation do not confirm cervical radiculopathy with sensory deficit. 总被引:1,自引:1,他引:0 下载免费PDF全文
U D Schmid C W Hess H P Ludin 《Journal of neurology, neurosurgery, and psychiatry》1988,51(2):182-187
Twenty eight patients with unilateral cervical radiculopathy were studied by somatosensory evoked potentials (SEPs) from nerve stimulation at the wrist and from skin stimulation at the first, third or fifth finger depending on the root involved. In order to evaluate the reliability of various "radicular SEP patterns" as described in the literature, absolute latencies and side-to-side differences of the brachial plexus component from the supraclavicular fossa (N9), the medullary component (N13) from the cervical vertebra Cv7, and the primary cortical component (N20, P25) were assessed. Side-to-side differences of the amplitudes of N20/P25 and of the conduction times across the intervertebral fossa (interval N9-N13) were analysed. After nerve stimulation, 68% of the patients had false negative findings on the symptomatic, while 36% had positive findings on the asymptomatic side. After segmental stimulation, 72% of the patients had false negative findings on the symptomatic, while 22% had positive findings on the asymptomatic side. It is concluded that SEPs following nerve and segmental stimulation do not reliably confirm clear-cut already established diagnoses of unilateral radiculopathy with sensory and motor deficit. Therefore, they will not be helpful in the electrophysiological investigation of cervicobrachialgias of unknown origin. 相似文献
979.
Reverse targeting of preventive care due to lack of health insurance 总被引:13,自引:1,他引:12
We analyzed patterns of receipt of preventive services among middle-aged women, with particular attention to health insurance coverage, based on data from the National Health Interview Survey. Lack of insurance was most prevalent among socioeconomically disadvantaged women at high risk for disease and was the strongest predictor of failure to receive screening tests. The relative risk of inadequate screening for uninsured compared with insured women was 1.60 (95% confidence interval [Cl], 1.40 to 1.83) for blood pressure checkups, 1.55 (95% Cl, 1.43 to 1.68) for cervical smears, 1.52 (95% Cl, 1.41 to 1.63) for glaucoma testing, and 1.42 (95% Cl, 1.33 to 1.51) for clinical breast examination. Controlling for demographic and health status variables did not diminish the effect of insurance coverage. We conclude that inadequate insurance coverage leads to "reverse targeting" of preventive care--that is, populations at highest risk are least likely to be screened. This compromises both the effectiveness and the cost-effectiveness of screening. 相似文献
980.
Summary A comparative study was undertaken to investigate the application of a specially adapted microsurgical Neodymium Yag Laser system with a wavelength of 1,319 m and a CO2 laser system for laser assisted microvascular end-to-end anastomosis (LAMA) of the rat femoral artery. Conventionally sutured anastomoses served as controls. Postoperative investigations included patency tests, light microscopy and tensile strength measurements. Both laser systems seem to be equally suitable for LAMA: The patency rates do not differ from those of sutured anstomoses and formation of microscopically small aneurysms occurred predominantly in control animals and only once in laser groups. The clamp time needed for LAMA was half the time that was needed for sutured anastomoses. Wound healing in all groups was similar with less fibrotic reactions and less foreign body granulomas in laser groups. At all intervals tensile strength was significantly higher for sutured anastomoses while differences between the CO2- and the ND: Yag-laser groups were not statistically significant. Potential applications in urology include microvascular anastomoses in erectile dysfunction, pediatric and reconstructive urology.Contains parts of a dissertation 相似文献