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21.
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OBJECTIVE: The aim of this study was to examine whether blood pressure reactions to mental stress predicted future blood pressure and hypertension. METHODS: Blood pressure was recorded at an initial medical screening examination after which blood pressure reactions to a mental stress task were determined. A follow-up screening assessment of blood pressure and antihypertensive medication status was undertaken 10 years later. Data were available for 796 male public servants, between 35 and 55 years of age upon entry to the study. RESULTS: Systolic blood pressure reactions to mental stress were positively correlated with follow-up screening systolic blood pressure and to a lesser extent, follow-up diastolic pressure. In multivariate tests, by far the strongest predictors of follow-up blood pressures were initial screening blood pressures. In the case of follow-up systolic blood pressure, systolic reactions to stress emerged as an additional predictor of follow-up systolic blood pressure. With regard to follow-up diastolic blood pressure, reactivity did not enter the analogous equations. The same outcomes emerged when the analyses were adjusted for medication status. When hypertension at 10-year follow-up was the focus, both systolic and diastolic reactions to stress were predictive. However, with correction for age and initial screening blood pressure, these associations were no longer statistically significant. CONCLUSIONS: The results of this study provide modest support for the hypothesis that heightened blood pressure reactions to mental stress contribute to the development of high blood pressure. At the same time, they question the clinical utility of stress testing as a prognostic device.  相似文献   
23.
After treatment with papain (6 mg/ml) for 1 h, P815 tumor cells became resistant to complement-mediated lysis by mouse alloantibodies of different specificities. Immunofluorescence and absorption studies indicated that this resistance was associated with removel of the corresponding antigenic determinants from the cell surface. In contrast, papain-treated tumor cells were fully susceptible to lysis by rabbit antiserum against P815 cells, indicating a) no alteration of the membrane sensitivity to complement damage, and b) a dissociation between structure and/or localization of allo- and xenoantigens. Papain-treated cells were also completely resistant to lysis by cytolytic T lymphocytes (CTL) during the first 60 min after completion of the enzyme treatment. Susceptibility to lysis by either CTL or alloantibody and complement reappeared within a few hours after incubation in culture medium and was virtually normal by 6 h. Treatment of P815 cells with trypsin (2 mg/ml) had no effect on either humoral or cellular lytic activities.  相似文献   
24.
Although complications of transseptosphenoidal (TSS) pituitary surgery have been discussed in the literature, there has not been an analysis of complication rates related to clinical features and the nature of the tumor. A retrospective review of 366 TSS procedures (354 patients) for excision of pituitary adenomas evaluated the incidence and management of perioperative complications. The mortality rate was 0.82%. The most frequently encountered complications were transient diabetes insipidus (8.74%) and cerebrospinal fluid (CSF) rhinorrhea (4.10%). Other complications included exacerbation of visual acuity and visual field defects, hemorrhage, hydrocephalus, and meningitis. The factors evaluated were gender, age, tumor size, hormone secretory status, and any history of prior pituitary surgery.There was a significantly higher incidence of transient diabetes insipidus in patients with hormone-secreting tumors. Minor and total complication rates were significantly increased in microadenomas, hormone-secreting tumors, in female patients, and in patients less than 60 years of age reflecting the increased incidence of transient diabetes insipidus in young female patients with hormone-secreting tumors. Observed intraoperative CSF leaks predisposed to postoperative CSF rhinorrhea. There were no identifiable risk factors for major complications.  相似文献   
25.
Summary During the use of a vertical flow enclosure of our own design for almost five years, bacteriological studies and the infection rates in different groups of patients have taught us the following:1. In a clean room operating theatre, the use of a respired air exhaust system improves the sterility compared with the use of ordinary masks. In a vertical flow enclosure, the chest, the arms, and the hands of the team are contaminated from respired airborne bacteria if helmets, etc., are not worn.2. In our vertical flow enclosure with almost continuous absolute sterility of the air, the infection rate in primary total hip replacement is very low and less than 1%, including early and late infections. Antibiotics have not been used.In secondary surgery, i.e., total hip replacement in hip joints previously operated upon, the infection rate is markedly higher, probably because of a flare-up of latent infection.Clean room surgery therefore, can only prevent air borne contamination, and no more; but this is very valuable.3. Vertical flow enclosures of the Charnley-Howorth (1975) and Weber et al. (1971) type provide considerable improvement in sterility of the air compared with adaptations of more conventional theatres. We recommend that these facilities be made available for implant surgery. It is also necessary to have a stringent operational policy with cooperation and discipline on the part of all members of the theatre team.
Résumé Durant l'utilisation, depuis plus de 5 ans, de la serre stérile à flux laminaire vertical que nous avons construite, nous avons pratiqué des études bactériologiques et pu comparer les taux d'infection suivant les groupes de patients.1. Dans une salle d'opération propre, la stérilité est considérablement améliorée par le port de casques possédant un système d'aspiration de l'air expiré, ceci par rapport au port de masques ordinaires. De plus, si l'on ne porte pas le casque dans une serre à flux laminaire vertical, le tronc, les mains et les membres supérieurs de l'équipe chirurgicale sont contaminés par les microbes en suspension dans l'air expiré.2. Dans notre serre où l'air est pratiquement stérile, le taux d'infections précoces et tardives est inférieur à 1% dans les arthroplasties de la hanche, et cela sans utilisation d'antibiotiques.Lors d'interventions dites secondaires, c'est-à-dire dans les cas déjà opérés au préalable, par exemple par ostéotomie, ostéosynthèse, etc., le taux d'infection est plus élevé. On doit probablement en rechercher la cause dans une contamination de la plaie lors de la première intervention, l'infection alors à l'état latent pouvant se réveiller à la faveur d'une nouvelle opération.En opérant dans une serre stérile, on peut donc prévenir la contamination par l'air ambiant, mais pas plus. Cela est cependant déjà très appréciable.3. Comparées aux salles d'opération conventionnelles modernes, les serres stériles à flux laminaire vertical, comme celle de Charnley-Howorth (1975) et Weber-Meierhans (1971), améliorent considérablement la stérilité de l'air. Surtout pour la chirurgie prothétique de la hanche, dont les risques d'infection sont élevés, nous recommandons l'emploi de ce genre d'installation. Mais il est nécessaire que tous les membres de l'équipe chirurgicale adoptent des règles très strictes de discipline.
  相似文献   
26.
Artificial liver   总被引:7,自引:0,他引:7  
Without transplantation, approximately 90% of patients with fulminant hepatic failure die. If patients receive a liver transplant, there is often a lag between the need for and the availability of a donor liver. Therefore, there is a definite need for a liver support system to support the patient's own liver function in fulminant hepatic failure and while awaiting transplantation. We have developed an artificial liver system that not only eliminates lipophilic toxins such as phenols, fatty acids, and mercaptans, but also hydrophilic ones such as ammonia. This artificial liver system consists of a monitor, an extracorporeal blood circuit that uses a hydrophilic polysulfone high-flux dialyzer to remove water-soluble metabolites, and a novel hydrophilic liquid membrane filter to remove lipophilic toxins. In more than 100 in vitro experiments using porcine (5 I) blood, the system was evaluated for its ability to remove toxins that are normally increased in hepatic failure. We found that phenol, cresol, and short- and medium-chain fatty acids can be almost completely eliminated from the blood within 5 h. In animal experiments using pigs, we also found no significant changes of blood gases, liver parameters, electrolytes, and blood cell counts.  相似文献   
27.
28.
The effect of a gluttony diet in healthy subjects was studied over an observation period of 12 months. Twenty-six agricultural workers, all of them Yemenite Jews, received a high-caloric, high-fat diet, and the changes in serum cholesterol (CH), high-density-lipoprotein-cholesterol, triglycerides, and body weight were assessed. Yemenite Jews as a group are characterized by low serum CH levels and by a low incidence of coronary artery disease. For a period of 7 months the subjects received a diet of 4553 cal/day, more than double their original "Yemenite diet". After this time they resumed their customary low-caloric diet for 3 months, and thereafter for another 2 months they continued with the high-caloric food regimen. The high-caloric, high-fat diet resulted in the expected increase of serum CH. A similar increase of high-density lipoprotein-CH was found. Serum triglyceride levels changed inversely to those of CH. It is suggested that the altered relation of calories derived from carbohydrates to those derived from fats brought about the decrease of triglycerides, and this irrespective of the increased intake of carbohydrates and fats. The rather small gain of body weight over the trial period--despite the doubled caloric intake--is similar to other studies that showed that the ability of normal individuals to gain weight through overeating varies considerably.  相似文献   
29.
This study describes the relation of different types of childhood trauma to the degree of dissociative experiences. Subjects were 198 consecutively admitted adolescent psychiatric patients, 11 to 19 years old (89 inpatients and 109 outpatients). All patients completed the Adolescent Dissociative Experiences Scale. A Checklist of Traumatic Childhood Events was filled out by clinicians. The results showed an increase in the degree of dissociative experiences in patients with a history of sexual abuse, physical abuse, neglect, and stressful life events. With the exception of life events, a moderate form of traumatic experience had the same effect on dissociative experiences as severe forms. The strongest effect was found for emotional neglect, which seems to be an important pathogenic risk factor. The results suggest that therapists and researchers should be aware that even less severe forms of abuse and neglect may have a significant impact on the development of dissociative psychopathology in adolescents.  相似文献   
30.
PURPOSE: Preclinical and clinical studies have demonstrated that inhibition of prenylation can radiosensitize cell lines with activation of Ras and produce clinical response in patients with cancer. The aim of this study was to determine the maximally tolerated dose of the dual farnesyltransferase and geranylgeranyltransferase I inhibitor L-778,123 in combination with radiotherapy for patients with locally advanced pancreatic cancer. EXPERIMENTAL DESIGN: L-778,123 was given by continuous intravenous infusion with concomitant radiotherapy to 59.4 Gy in standard fractions. Two L-778,123 dose levels were tested: 280 mg/m2/day over weeks 1, 2, 4, and 5 for dose level 1; and 560 mg/m2/day over weeks 1, 2, 4, 5, and 7 for dose level 2. RESULTS: There were no dose-limiting toxicities observed in the eight patients treated on dose level 1. Two of the four patients on dose level 2 experienced dose-limiting toxicities consisting of grade 3 diarrhea in one case and grade 3 gastrointestinal hemorrhage associated with grade 3 thrombocytopenia and neutropenia in the other case. Other common toxicities were mild neutropenia, dehydration, hyperglycemia, and nausea/vomiting. One patient on dose level 1 showed a partial response of 6 months in duration. Both reversible inhibition of HDJ2 farnesylation and radiosensitization of a study patient-derived cell line were demonstrated in the presence of L-778,123. K-RAS mutations were found in three of the four patients evaluated. CONCLUSIONS: The combination of L-778,123 and radiotherapy at dose level 1 showed acceptable toxicity in patients with locally advanced pancreatic cancer. Radiosensitization of a patient-derived pancreatic cancer cell line was observed.  相似文献   
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