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171.
To our knowledge, only 3 patients with an extragonadal germ cell tumor of the prostate have been described in the literature until now. We here present a patient with a germ cell tumor arising in the retroperitoneum, invading the prostate, which was successfully treated by a combination of chemotherapy and nonmutilating surgery.  相似文献   
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The laryngeal mask in failed intubation   总被引:1,自引:0,他引:1  
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Abstract Several methods have been used to predict successful weaning and extubation among chronic obstructive pulmonary disease (COPD) patients. The objective of this study is to determine whether carbon dioxide recruitment threshold (PCO2RT) can be used as adjunct to conventional weaning parameters to predict early weaning and successful extubation. Twelve COPD patients who were ready to be extubated based on conventional weaning parameters were divided into group A ( n = 7) and group B ( n = 5). Group A were those patients with better weaning parameters and hence a higher probability of successful extubation as compared to group B. Carbon dioxide apnoeic threshold (PCO2AT) was obtained by hyperventilating the patient using an increment of two breaths per min until apnoea occurs. At this point, the PCO2AT or the PaCO2 during said apnoeic period was recorded. A dead space of 150 cc is then added to the circuit until the patient starts to breathe as evidenced by the sensitivity trigger indicator. The PCO2 obtained at this period is termed PCO2RT. After weaning for 30 min on a T-tube, another arterial blood gas is determined and this is called the PCO2SB or the CO2 level after 30 min on spontaneous breathing. If the PCO2SB-PCO2RT difference is high with a sensitivity of 85.71% and specificity of 100% vs sensitivity of 57.14% and specificity of 60% using the conventional weaning parameters. Thus an increase in PCO2SB at 30 min T-tube is indicative of impending respiratory pump failure and that other causes of failure to wean must be investigated.  相似文献   
176.
For the past 10 years the alfa-hydroxyacids and the bovine collagen injection have been used for peeling and the correction of multiple skin diseases. Until now, such progressive achievement has occurred in separate parallels just like the indications that have been held distinct. However, the studies carried out in order to clarify the mechanical action of the two substances have shown a common and fundamental denominator: the stimulation of synthesis of the new collagen in the patient's skin. On the basis of these results and the existence of common clinical indications of the use of glycolic acid and collagen, the authors have worked out a protocol involving a combined and contemporary application in progressive steps. They developed the rationales of such protocol and analyzed the results of its application on a number of carefully selected patients for a clinical comparison and on a sample of rats for a histological comparison. They have concluded that the contemporary use of glycolic acid and bovine collagen is a simple and safe method whose synergy action leads to more intense and long-lasting effects than the ones observed in the isolated application of the two substances. The authors have also obtained interesting and significant histological results.  相似文献   
177.
Morphologic changes in the testes of adult mice after experimentally induced cryptorchidism were studied by light microscopy and stereology. Increasing duration of cryptorchidism resulted in a gradual decrease in the volume of seminiferous tubules per testis, and this was associated with germ cell degeneration. The volumes of Sertoli cell lipid droplets increased, and dilations of the intercellular space between the Sertoli cell junctions was observed in the cryptorchid testis. The luminal volume of the seminiferous tubule was reduced by 50% after 28 days of cryptorchidism. However, the volumes of intertubular tissue and Leydig cells in control and cryptorchid testes were not significantly different. Leydig cell number per testis increased, and the average volume of a Leydig cell decreased gradually with the progression of the cryptorchid state. The volume of the connective tissue cells in the intertubular area increased, but no significant volume change was observed in the volume of intertubular macrophages. After 28 days, the cryptorchid testis contained a significantly increased volume of blood vessels and a reduced volume of lymphatic space per testis. These observations clearly demonstrate that, although the mouse is a species closely related to the rat, the morphologic changes that occur in the Leydig cell population after induction of experimental cryptorchidism in this species is different.  相似文献   
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Respiratory infections (RI) are one of the major complaints in children and adolescents, and represent a demanding challenge for the pediatrician. It has been estimated that at least 6% of Italian children younger than 6 yr of age present recurrent respiratory infections (RRI). Children with RRI are not affected by severe alterations of the immune system. RRI represent essentially the consequence of an increased exposure to infectious agents during the first years of life, when immune functions are still largely immature. Several social and environmental factors, such as day-care attendance, family size, air pollution, parental smoking, and home dampness, represent important risk factors for airway diseases and may contribute in various degrees to determine the incidence of RRI. The main problem for the pediatrician is to discriminate normal children with high RI frequency related to an augmented exposure to environmental risk factors from children affected by other underlying pathological conditions (immunological or not), predisposing to infectious diseases. When RRI diagnosis has been formulated, removal of environmental risk factors (i.e. precocious day-care attendance, smoking in the household) must first be suggested.  相似文献   
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