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21.
Moxalactam for the treatment of bacterial meningitis in children   总被引:2,自引:0,他引:2  
Increasing resistance to antibiotics in meningeal pathogens has stimulated a search for new antimicrobial agents for the treatment of bacterial meningitis. Moxalactam penetrates well into infected cerebrospinal fluid (CSF) and is highly active against most gram-negative bacteria. The clinical efficacy and safety of moxalactam in the treatment of childhood meningitis caused by Haemophilus influenzae (25 patients) or Neisseria meningitidis (five patients) was evaluated in a random, uncontrolled study. The penetration of the antibiotic into CSF was also evaluated in these patients and in another five children with bacterial meningitis. The clinical results were excellent, with 29 of 30 cases cured. The single adverse clinical reaction noted was the development of a wound hematoma in a postoperative patient; this problem may have been related to moxalactam therapy. The levels of moxalactam achieved in CSF greatly exceeded the minimal bactericidal concentrations for the infecting organisms. Moxalactam appears to be safe and effective as primary therapy for meningitis caused by H influenzae or N meningitidis.  相似文献   
22.
Partial left ventriculectomy is a new surgical option quickly introduced into clinical use worldwide for treating end-stage heart failure in patients with dilated cardiomyopathy. Due to the overwhelming success of this new kind of surgical treatment for dilated cardiomyopathy, experimental research on the physiological and pathophysiological basis was initially not performed. Now, demands for an appropriate animal model have arisen more and more since the outcome of patients treated by partial left ventriculectomy has differed considerably. This review summarizes available experimental models for heart failure in large animals, and discusses their suitability for research on partial left ventriculectomy.  相似文献   
23.
Pathogenesis and pathophysiology of meningitis   总被引:3,自引:0,他引:3  
Advances in the understanding of the pathogenesis and pathophysiology of meningitis have occurred primarily through the use of experimental animal models. These models have proven to be particularly valuable in experimental bacterial meningitis, focusing on the bacterial virulence factors responsible for the initiation of infections, CNS invasion, and induction of SAS inflammation. Recent studies have examined the formation of host inflammatory cytokines in response to these virulence factors. These cytokines may be responsible for many of the pathophysiologic consequences of bacterial meningitis (eg. increased BBB permeability, cerebral edema, and increased intracranial pressure). Meningitis due to C. neoformans occurs most commonly in patients with defects in cell-mediated immunity (eg, AIDS), and the depletion of T helper cells in AIDS patients may allow unrestricted cryptococcal growth. Viral meningitis is an illness of low prevalence when compared with the overall occurrence of viral infections at other sites. CNS infection usually occurs by means of traversal across barriers that normally exclude viral invasion of the CNS, primarily through hematogenous dissemination from initial sites of infection. These advances in the pathogenesis and pathophysiology of bacterial, fungal, and viral meningitis may lead to the development of innovative treatment strategies for these disorders.  相似文献   
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Cardiac pacing in children still presents problems concerning the most favorable placement of the generator and, in particular, the growth-induced electrode complications. Whereas in infants epicardial implantation is unavoidable, one would prefer transvenous placement in older children to permit replacement or removal without extensive operative measures. The use of actively anchorable endocardial leads seems advantageous because of the possibility of placing long electrode loops in the cavity of the right atrium without increasing the risk of dislodgement. In this way overextension of the lead during growth may be avoided. Since June 1975 we have performed ventricular pacing in 10 children, aged 2 to 9 years, by using a transvenous screw-in electrode (surface 6 mm2). Acute threshold values ranged from 0.4 to 0.7 mA ap a pulse duration of 1.0 msec and sensitivity between 6.5 and 8.7 mV. Electrode function has been without complications up to now. In 6 patients we implanted programmable pacemaker systems which allowed postoperative threshold measurements. The chronic threshold value has not increased above 2.3 mA in any of these cases. In our opinion, actively anchorable endocardial leads present significant advantages for pacing in childhood.  相似文献   
26.
BACKGROUND: the incidence and prevalence of patients with advanced heart failure is increasing worldwide and the number of cardiac transplantations remains limited. AIMS: it was the aim of the study to describe our experience with the increasing number of available medical, interventional and cardiac surgery options, and to assess heart failure survival score predictability in an academic heart failure center within a 1-year follow-up. METHODS AND RESULTS: in all patients who were referred for cardiac transplant evaluation within a 12-month period between April 1998 and March 1999 at our Interdisciplinary Heart Failure and Transplant Program, our team assessed all medical interventions as well as interventional and surgical treatment options that were available, based on the clinical profile on initial presentation. In 92% of the 120 patients referred for cardiac transplantation evaluation, drug therapy could be optimized. A considerable number of patients could be subjected to an organ-preserving intervention or surgery, either PTCA (n=11), CABG (n=4), valve repair (n=7), multisite pacing (n=7), or partial ventricular resection (n=5). Only a small group of patients with the worst heart failure survival score were listed for heart transplantation (n=17) or received a ventricular assist device (n=3). CONCLUSIONS: within a contemporary cohort of advanced heart failure patients, only a small number of patients will undergo cardiac transplantation, which is predictable by the heart failure survival score. Most patients will undergo optimized medical therapy and a considerable number will be subjected to interventional or surgical treatment options.  相似文献   
27.
This study was performed to determine the risk of family members of anti-hepatitis C virus (HCV)-positive hemophilia patients (index patients) for infection with HCV compared with the risk of acquiring hepatitis B virus (HBV), human immunodeficiency virus (HIV), and hepatitis A virus (HAV) infection. All index patients (n = 141) were found to be positive by first and second generation anti-HCV enzyme immunoassays (EIAs). Among their household contacts (n = 228), 224 were negative and 1 positive by both assays. Three contacts gave positive results in first generation anti-HCV EIA and negative results in second generation assay. This latter result was confirmed by further tests (neutralization test, synthetic peptides, and supplemental assay). Percent positivity for anti-HBc was about the same in non-sexual household contacts and sexual partners (13 of 109 [12%] and 7 of 54 [13%], respectively). Percent prevalence of anti-HBc was higher in contacts of index patients with chronic hepatitis B than in those of index patients who had recovered from that disease (6 of 20 [30%] and 14 of 133 [10%], respectively; P < .05). The HBV infection rate of contacts participating in controlled self-treatment was not higher than that of controls (3 of 57 [5%] and 10 of 98 [10%], respectively). Of 44 sexual partners, 5 (11%) were found to be positive for anti-HIV. Prevalence of anti-HAV matched with the age-related distribution in the German population. These findings suggest that intrafamilial transmission of HCV to family members of hemophilia patients is uncommon. In contacts of hemophilia patients, the risk of acquiring HBV infection seems to be as high in household contacts as in sexual contacts. Participation in controlled self-treatment does not appear to be an additional risk for HCV and HBV infection. There is no doubt that sexual transmission of HCV is less common than that of HBV and HIV.  相似文献   
28.
The effects of ventricular assist devices (VADs) on the coagulation system are not yet fully understood. The high molecular weight (HMW) von Willebrand factor (vWF) decrease observed after continuous flow left VAD (CF-LVAD) implantation has been well documented by several studies. However, not all CF-LVAD recipients suffer from bleeding complications so that additional risk factors need to be identified by further studies. If predictors of bleeding complications were known in more detail this would facilitate the development of individualized strategies for anticoagulation and antiplatelet therapy in VAD recipients. In the face of the significant mortality associated with bleeding this complication remains a major obstacle in improving patient outcome which should be overcome.  相似文献   
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30.
Bacterial meningitis: recent advances in pathophysiology and treatment   总被引:12,自引:0,他引:12  
PURPOSE: To review recent advances in the understanding of pathogenic and pathophysiologic mechanisms underlying bacterial meningitis that may lead to the development of adjunctive strategies for treating this disorder. DATA IDENTIFICATION: Studies published from 1975 to 1989 were identified using Index Medicus and by reviewing the bibliographies of identified articles. STUDY SELECTION: We reviewed the experimental and human studies evaluating pathogenesis, pathophysiology, and antimicrobial treatment of bacterial meningitis, as well as those reviews that have contributed to our understanding of meningitis. DATA EXTRACTION: We evaluated the data on the pathogenesis, pathophysiology, and treatment of bacterial meningitis and considered in depth the information from animal models that may have potentially important applications in the treatment of human disease. RESULTS OF DATA SYNTHESIS: Penicillin and ampicillin remain the drugs of choice for meningitis caused by Streptococcus pneumoniae and Neisseria meningitidis. The third-generation cephalosporins have revolutionized the treatment of gram-negative bacillary meningitis; one such agent, ceftazidime, is also useful for treating Pseudomonas aeruginosa meningitis. Modification of subarachnoid space inflammation by anti-inflammatory agents may lessen many of the pathophysiologic consequences of bacterial meningitis. A recent study of adjunctive dexamethasone therapy in infants and children with bacterial meningitis showed that the incidence of long-term neurologic sequelae was lower in the corticosteroid group. CONCLUSION: Future therapy for bacterial meningitis will use recent developments in the understanding of pathogenic and pathophysiologic mechanisms underlying this disease. Additional studies using monoclonal antibodies against specific virulence factors and investigations into the production of inflammatory cytokines in response to bacterial cell products may lead to additional treatments that decrease the high morbidity and mortality in patients with bacterial meningitis.  相似文献   
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