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11.
Long-term oral anticoagulation requires careful patient monitoring in order to optimize results and to limit hemorrhagic or thromboembolic complications of treatment. For this reason, any improvement in anticoagulant control and management can be expected to have far-reaching consequences in extending longevity and decreasing complications in anticoagulated patients after heart valve surgery. Because one attractive means of improving anticoagulant management is to give patients a share of the responsibility, a program was designed to encourage patients to take an active role in monitoring their own prothrombin time (PT) and managing their own oral anticoagulation. During the period from August 1986 to February 1992, 600 patients requiring long-term anticoagulation, mainly after heart valve replacement, were trained to measure their own PT at the Cardiac Rehabilitation Center (Herz-Krauslauf-Klinik, Bad Berleburg, Germany) and to manage their own therapy: 216 patients could be followed with regard to their self-determined prothrombin times. The results were within the target range in 83.1% of the PT determinations (n=12,306 measurements) taken by the patients themselves. Neither major bleeding nor thromboembolic complications were observed in 205 patient-years of self-monitoring of PT and self-management of oral anticoagulation.  相似文献   
12.
Antimycotic Agents, XX Bioisosteric 6-Arylpyrimidine Derivatives Condensation of N-(2-hydroxyethyl)-N-methylguanidine-sulfate ( 1 ) with the β-diketones 4a - e bearing 1-aryl substituents leads to the bioisosteric 2-[(2-hydroxyethyl)-methylamino]-6-arylpyrimidines 5a - e . Compounds 5a - c exhibit significant antimycotic in vivo and in vitro activities.  相似文献   
13.
Background: Sweating, vasoconstriction, and shivering have been observed during general anesthesia. Among these, vasoconstriction is especially important because-once triggered-it minimizes further hypothermia. Surprisingly, the core-temperature plateau associated with vasoconstriction appears to preserve core temperature better in infants and children than adults. This observation suggests that vasoconstriction in anesthetized infants may be accompanied by hypermetabolism. Consistent with this theory, unanesthetized infants rely on nonshivering thermogenesis to double heat production when vasoconstriction alone is insufficient. Accordingly, the authors tested the hypothesis that intraoperative core hypothermia triggers nonshivering thermogenesis in infants.

Methods: With Ethics Committee approval and written parental consent, the authors studied six infants undergoing abdominal surgery. All were aged 1 day to 9 months and weighed 2.4-9 kg. Anesthesia was maintained with propofol and fentanyl. The infants were mechanically ventilated and allowed to cool passively until core (distal esophageal) temperatures reached 34-34.5 degrees Celsius. Oxygen consumption-the authors' index of metabolic rate- was recorded throughout cooling. Because nonshivering thermogenesis triples circulating norepinephrine concentrations, arterial blood was analyzed for plasma catecholamines at [nearly equal] 0.5 degrees Celsius intervals. Thermoregulatory vasoconstriction was evaluated using forearm - fingertip, skin-surface gradients, with gradients exceeding 4 degrees Celsius, indicating intense vasoconstriction. The patients were subsequently rapidly rewarmed to 37 degrees Celsius. Regression analysis was used to correlate changes in oxygen consumption and plasma catecholamine concentrations with core temperature.

Results: All patients were vasoconstricted by the time core temperature reached 36 degrees Celsius. Further reduction in core temperature to 34-34.5 degrees Celsius did not increase oxygen consumption. Instead, oxygen consumption decreased linearly. Hypothermia also failed to increase plasma catecholamine concentrations.  相似文献   

14.
Zusammenfassung Nur attenuierte Lebendimpfstoffe haben sich bisher für die Prävention der Mumpsvirusinfektion als wirksam erwiesen. Die verschiedenen Impfstämme unterscheiden sich im. Grad ihrer Attenuierung, die schwer steuerbar ist. Der Grat zwischen Restvirulenz und Überattenuierung ist schmal. Wenig attenuierte Impfstämme zeigten zwar eine höhere Immunogenität, aber auch häufiger Impfkomplikationen. Heute werden nur noch relativ stark abgeschwächte Impfstämme verwendet, die zwar kaum je zu einer impfassoziierten Erkrankung führen, deren Immunogenität aber geringer sein dürfte als ursprünglich angenommen.
Summary The prevention of mumps virus infection reties on the application of live, attenuated mumps virus vaccines. The process of attenuation from a wildtype mumps isolate to a safe vaccine has been empirical. A lower degree of attenuation results in solid immunity but carries an increased risk of post-vaccination meningitis due to the vaccine strain. Currently used vaccine strains are highly attenuated and essentially free of vaccine strain induced disease. However, their immunogenicity may be lower than previously reported.

Résumé La prévention des oreillons est effectuée grâce aux vaccins contenant des virus ourliens vivants atténués. La différence entre un virus ourlien sauvage et un atténué est très petite. Un virus légèrement atténué engendre une forte immunité mais augmente le risque de développer des méningites postvaccinales. Actuellement on utilise des souches fortement atténuées qui ne font que très peu de complications mais dont l'immunogénicité semble plus faible que prévue.
  相似文献   
15.
OBJECTIVE: The objectives of the present study were: (1) to analyze the cry features of infants with cleft lip and palate (UCLP) by means of spectral analysis, (2) to describe changes of the acoustic parameters from birth until 9 months of age, and (3) to compare these data with existing cry data of infants without cleft (control group). DESIGN: The study was designed on a interdisciplinary, prospective, and longitudinal basis. SETTING: Interdisciplinary study: (1) Institute of Anthropology at the Humboldt-University, Berlin; (2) Heidelberg University Hospital: Interdisciplinary Cleft Palate and Craniofacial Center. PATIENTS AND METHOD: The cry parameters of five patients with complete unilateral cleft lip, alveolar ridge, and hard and soft palate were analyzed from birth to 9 months of age. The patients were treated with the same protocol. At the age of 24 months, sensomotor development was assessed using the KIPHARD test. Perceptual judgment of speech, performed after 36 months of life, included nasal resonance, nasal emission of air, articulation disorders, and speech intelligibility. MAIN OUTCOME MEASURE: The cry parameters of fundamental frequency (F(0)), pitch period perturbation quotient (PPQ), and cry duration (Tsam) were analyzed. RESULTS: Contrary to the expectation that laryngeal parameters are not affected by vocal tract malformations, differences of cry parameters were found between the patients with UCLP and the non-cleft group. Particularly, the F(0) and its short-time variability (PPQ) were affected. CONCLUSIONS: The preliminary results of this study showed that F(0) and PPQ of spontaneous cries are influenced in patients with UCLP, and a cry analysis might become a noninvasive tool for early detection of an at-risk status for neuromuscular development and prediction of an at-risk status for later speech and language acquisition in infants with cleft lip and palate. Future research strategies are outlined.  相似文献   
16.
The acute “axonal” form of Guillain—Barre syndrome is characterized by rapid progression to severe widespread paralysis and respiratory dependence within 2–5 days of the onset of weakness with very poor and delayed recovery. In 3 cases studied within the first 7 days, the maximum thenar, hypothenar, tibialis anterior, and extensor digitorum bervis “M” potentials were either very reduced in size or absent in response to stimulation at the usual most distal sites of stimulation at the wrist, fibular head, and/or ankle. In the latter instances, advancing the site of stimulation closer to the motor point often evoked an M response. Furthermore, continued distal advance of the site of stimulation evoked progressively larger sized M potentials. Over succeeding days even these very distally evoked M potentials. Maximum conduction velocities in motor nerve fibers just prior to total loss of excitability were often very reduced. The pattern in these cases is most consistent with progressive loss of excitability and conduction in nerve fibers undergoing axonal degeneration, although coexisting primary demyelination in the terminal segment could not be excluded as the basis for the sometimes very slowed conduction velocities. © 1993 John Wiley & Sons, Inc.  相似文献   
17.
18.
Curing cancers is one of the most challenging tasks of modern medicine. The major problem is the heterogeneity of human tumours and thus finding a 'universal' target for cancer treatment. The discovery that the expression of the enzyme telomerase is a hallmark of immortality and cancer, and that it is found in the majority (>85%) of human tumours but is repressed in most normal cells, has therefore caused considerable excitement. These observations led to the design of potential telomerase inhibitors and ideas about targeting telomerase in the clinic. To date, several classes of telomerase inhibitory agents have been identified and are in preclinical development. However, the approach has not yet been tested clinically. Because of the proposed function of telomerase, and the understanding that replicative cell senescence or cell death result from progressive telomere shortening during successive cell divisions, even complete enzyme inhibition will not produce immediate cell death. Designing clinical trials for promising telomerase inhibitors requires consideration of the novel mechanism of action of these drugs. A lag period between initiation of treatment and occurrence of effects is likely, and thus anti-telomerase therapy might best be given in adjuvant treatment protocols after initial tumour debulking therapy and in combination with other cytostatic agents. The available knowledge of telomerase biology and its association with human tumours suggests that telomerase inhibition might prove a valuable addition to current cancer treatment regimens.  相似文献   
19.
20.
Enterohemorrhagic Escherichia coli (EHEC) strains of serogroup O145 are emerging as causes of diarrhea and the hemolytic-uremic syndrome. However, there have been few genetic analyses of this EHEC group. We investigated the serotypes, virulence genes, plasmid profiles, pulsed-field gel electrophoresis (PFGE) patterns, and genetic variability of the fliC and eae genes in 120 EHEC O145 strains isolated from cases of hemolytic-uremic syndrome (n = 24) or diarrhea (n = 96) in Germany between 1996 and 2002. Three isolates belonged to serotype O145:H28, one to serotype O145:H25, and 116 were nonmotile (O145:H(-)). One hundred fourteen of the nonmotile strains shared fliC restriction fragment length polymorphism (RFLP) patterns identical to that of the O145:H28 strains. The remaining two nonmotile strains displayed a fliC-RFLP pattern identical to that of the O145:H25 strain. Each of the 117 strains with the fliC-RFLP(H28) pattern harbored eae gamma, whereas the three strains with the fliC-RFLP(H25) pattern possessed eae beta. Five different stx genotypes, six combinations of plasmid-encoded putative virulence genes, 29 plasmid profiles, and 47 PFGE types were identified. Strains within some of the PFGE types could be further subtyped by means of distinct plasmid profiles. These data demonstrate that the EHEC O145 serogroup is comprised of two different serotypes that possess distinct eae types. The heterogeneity of EHEC O145 strains at the chromosomal and plasmid level, in particular the high diversity in PFGE patterns, provides a basis for molecular subtyping of these pathogens.  相似文献   
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