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101.
Two home recording systems, the Telediagnostic (TDS) and the Medilog, were used to compare sleep in the home environment with recorded sleep from the laboratory environment in 24 normal subjects (ages 21–42). Each subject was recorded for 4 consecutive nights, 2 each in the home and laboratory environments, in a counterbalanced order. All recorded sleep was manually scored for sleep latency, sleep efficiency, sleep maintenance, sleep stage architecture, REM sleep latency, and REM sleep activity. Complete data on 10 subjects using the TDS (Experiment 1) and 10 subjects using the Medilog System (Experiment 2) were available for statistical analyses. There were no significant differences in any of the nine sleep parameters tested by recording environment or order of recording environments using the Telediagnostic or the Medilog systems. Comparing the sleep parameters recorded across experiments, subjects recorded with the TDS took longer to fall asleep in the home environment than those subjects recorded with the Medilog System. The TDS demonstrated a clear superiority over the Medilog System in its sleep monitoring feasibility and its practical and economic advantages for carrying out home sleep studies.  相似文献   
102.
Bonding effectiveness of adhesive luting agents to enamel and dentin.   总被引:6,自引:0,他引:6  
OBJECTIVES: The bonding effectiveness of five adhesive luting agents to enamel and dentin using different application procedures was determined using a micro-tensile bond strength protocol (microTBS). METHODS: Enamel/dentin surfaces of human third molars were flattened using a high-speed diamond bur. Composite resin blocks (Paradigm, 3M ESPE) were luted using either Linkmax (LM; GC), Nexus 2 (NX; Kerr), Panavia F (PN; Kuraray), RelyX Unicem (UN; 3M ESPE) or Variolink II (VL; Ivoclar-Vivadent), strictly following manufacturers' instructions. For some luting agents, modified application procedures were also tested, resulting in four other experimental groups: Prompt L-Pop+RelyX Unicem (PLP+UN; 3M ESPE), Scotchbond Etchant+RelyX Unicem (SE+UN; 3M ESPE), Optibond Solo Plus Activator+Nexus 2 (ACT+NX; Kerr) and K-Etchant gel+Panavia-F (KE+P; Kuraray). The experimental groups were classified according to the adhesive approach in self-adhesive (UN), etch-and-rinse (ACT+NX, NX, KE+P, SE+UN and VL when bonded to enamel) and self-etch adhesive luting agents (LM, PLP+UN, PN and VL when bonded to dentin). The specimens were stored for 24h in distilled water at 37 degrees C prior to microTBS testing. The Kruskal-Wallis test was used to determine pairwise statistical differences (p<0.05) in microTBS between the experimental groups. RESULTS: When bonded to enamel, ACT+NX (15 MPa) and UN (19.6 MPa) scored significantly lower than VL (49.3 MPa), LM (49.2 MPa), PN (35.4 MPa) and SE+UN (35.2 MPa), while PLP+UN (23.5 MPa) showed a significantly lower microTBS than VL (49.3 MPa) and LM (49.2 MPa). No significant differences were noticed between VL (49.3 MPa), LM (49.2 MPa), NX (37.9 MPa), KE+PN (38.8 MPa), PN (35.4 MPa) and SE+UN (35.2 MPa). Regarding the bonding effectiveness to dentin, all luting agents bonded equally effectively (UN: 15.9 MPa; LM: 15.4 MPa; PN: 17.5 MPa; NX: 22.3 MPa), except VL (1.1 MPa), SE+UN (5.9 MPa) and ACT+NX (13.2 MPa). VL revealed an exceptionally high number of pre-testing failures, most likely due to a combined effect of not having cured the adhesive separately and an insufficiently light-cured luting agent. SIGNIFICANCE: Following a correct application procedure, the etch-and-rinse, self-etch and self-adhesive luting agents are equally effective in bonding to enamel and dentin. Several factors negatively influenced bond strength such as bonding RelyX Unicem to enamel without prior phosphoric acid etching; no separate light-curing of a light-polymerizable adhesive prior to cementation, use of a light-polymerizing adhesive converted into a dual-polymerizing adhesive, and use of a dual-cure luting agent with a low auto-polymerizable potential.  相似文献   
103.
Summary Neurotoxicity is a well-recognized and commonly observed side effect associated with the use of vincristine sulfate in cancer chemotherapy. The clinical manifestations of vincristine neuropathy cover a wide spectrum of peripheral neurologic dysfunctions that have been described to be reversible and cumulative in most instances (1, 2). Paresthesias, loss of tendon reflexes, and progressive weakness are the most common clinical features (3, 4). Sensory impairment, cranial nerve palsies, gastrointestinal disturbances, and autonomie dysfunctions including atonic bladder, impotence, and orthostatic hypotension may occur (5). Acute CNS complications, usually presenting as generalized seizures, are extremely rare and only a few cases have been reported which were without underlying biochemical or structural abnormalities (1, 5–9). We describe the case of a woman with multiple myeloma, who developed fulminant encephalopathy following 4 days of continuous vincristine, adriamycin, and day 1–4 pulse dexamethasone (VAD) combination therapy.  相似文献   
104.
This paper analyzes social learning processes in mutual support groups that were developed to facilitate clients' understanding of cardiovascular diseases and their responsibilities for health maintenance. It is based upon a 3-year study of supportive health care in a community of low-income Black and Latino families in south-central Los Angeles, California. Participant-observation and small group research have been employed to understand the learning styles that help chronically ill clients to identity their roles and thereby reduce the anxiety and uncertainty that often accompany a therapeutic regimen.  相似文献   
105.
Possible hepatitis B immunization of all newborns, regardless of the mother's HBsAg status, is a strategy under consideration for selected hyperendemic areas in Italy. Sardinia is one such area. However, in 1987 in Sardinia, the prevalence of hepatitis B markers in children under 11 years was estimated at 1.7% and the prevalence of hepatitis B surface antigen (HBsAg) at 0.2%. A much higher prevalence of HBsAg was recently observed among adults in this area: 8.7% among men and 5.2% among pregnant women. This contrasting pattern is unlikely to be due to bias: the sampling procedures adopted were appropriate and the percentage of refusals was very low (2.2%). The observed low hepatitis B marker prevalence in young age groups might be the result of a cohort effect due to the improved socio-economic conditions and changes in behaviour that have occurred in Sardinia over the last few years.The finding of only 3 HBsAg+ individuals out of 1,826 children tested, in spite of the 5.2% HBsAg prevalence among pregnant women in that region, is probably attributable to the low proportion of HBeAg positive individuals among the HBsAg+ carrier mothers in this area.At present, immunization of all newborns in Sardinia cannot be recommended.  相似文献   
106.
Zusammenfassung Fallbericht über einen 45jährigen Mann, bei dem es im Rahmen einer histologischen verifizierten Mycosis fungoides offensichtlich im Verlauf eines leukämischen Schubes zur Hirnbeteiligung mit zwei Herden in der linken Parietal- bzw. Parieto-Temporalregion kam. Bioptisch fanden sich lymphomartige Gefäß- und Gewebsinfiltrate mit einzelnen Riesenzellen (Lutzner-Zellen) ohne sichere Meningealaussaat. Die Liquorcytologie ergab präund postoperativ vereinzelt atypische Lymphocyten und Mononucleäre, darunter eine ultrastrukturell charakteristische Sézary-Zelle. Im peripheren Blut waren nach postoperativem Rückgang der hohen Leukocytenzahl die in den Hautinfiltraten vorhandenen atypischen Lymphocyten (Sézary-Zellen) morphologisch und an Hand cytochemischer (-Glucuronidase) und immunologischer (Rosetten mit Schafserythrocyten) Marker nachweisbar. Das Krankheitsbild wird als cerebrale Manifestation in der leukämischen Phase einer Mycosis fungoides im Sinne eines Sézary-Syndroms angesehen.
Cerebral involvement in the Sézary syndrome
Summary Two foci of histologically verified mycosis fungoides were found in the left parietal region of a 45-year-old man with involvement of the brain during an exacerbation of leukemia. There was perivascular and diffuse infiltration with lymphoma-like cells and occasional giant (Lutzner) cells but no involvement of the meninges. Both before and after operation the CSF contained a few atypical lymphocytes and mononuclear cells, one of which showed ultrastructurally the deeply clefted nucleus of Sézary cells. Atypical cells were confirmed morphologically in the peripheral blood, as well as by cytochemical (-glucuronidase) and immunological (rosettes with SRBC) markers, after the postoperative leucocytosis had subsided. It is suggested that this CNS involvement during a leukemic conversion phase of mycosis fungoides is consistent with the Sézary syndrome.
  相似文献   
107.
Nocturnal penile tumescence in depressed men   总被引:1,自引:0,他引:1  
Nocturnal penile tumescence recordings were performed in 10 men with major depression and 10 age-matched healthy control subjects to evaluate the possibility that clinical disturbances in sexual interest and activity often reported by depressed persons are associated with objective changes in sexual neurophysiology. Depressed men had significantly reduced minutes of tumescence time, a finding that was not attributable to alterations in sleep efficiency or REM sleep time. Three depressed men had baseline tumescence profiles suggestive of "organogenic" impotence, which improved after recovery. The authors discuss the implications of such findings for clinical practice and future research.  相似文献   
108.
Intradermally (I.D.) administered reduced doses of HB-Vax and Hevac-B were tested against the standard protocols for administering these two vaccines. Immunogenicity, efficacy and possible side effects were evaluated.Four-hundred-sixty-two healthy subjects were vaccinated as follows: Fifty-two subjects received HB-Vax and 99 Hevac B according to the standard regimens. The remaining subjects received 3 I.D. injections in the deltoid region at one-month intervals in the following doses: 165 subjects with 2 g doses of HB-Vax, 118 subjects with 1 ug doses of Hevac-B and 28 subjects with 0.5 g (minimal) doses of Hevac-B. Post-vaccination tests (anti-HBs titres and other serological markers for HBV) were to be performed 30, 60, 90, 180, 270 and 360 days after the first injections.Side effects seen with the experimental protocols were acceptable and limited to local reactions. It was found that, on the whole, reduced I.D. doses of both vaccines produced very high immune responses showing a consistently greater efficacy than those of the standard protocols, though the differences were not always statistically significant.Ninety days after the first injections, 80.8% and 82.7% of subjects vaccinated with reduced I.D. doses of HB-Vax showed seroconversion as opposed to only 62.0% of those receiving standard protocol HB-Vax.Seroconversion rates at 90 days in subjects receiving reduced I.D, doses of Hevac-B were 92.0% and 87.996 and for those receiving the minimal doses of this vaccine, 94.1% The rate of seroconversion obtained with standard administration of Hevac-B was 83.8%. The antibody titres in the experimental groups tended to increase up to the 180th day and were generally higher than those obtained with standard protocols. The titres remained very high 270 days after the first injection.Corresponding author.  相似文献   
109.
110.
Summary

The authors evaluated the in-vitro antibacterial activity of piperacillin alone and of piperacillin combined with tazobactam, a new beta-lactamase inhibitor, on 398 clinical isolates, both Gram-positive and Gram-negative. The piperacillin/tazobactam combination was evaluated in the fixed ratio 8:1. The vast majority of the microorganisms tested had reduced susceptibility to piperacillin (minimum inhibitory concentration (MIC) range 0.12— > 256 mg/1) due to beta-lactamase production.

The following results were obtained: against Haemophilus influenzae, tazobactam was effective in reducing the MICs of piperacillin by 512 fold. The activity of piperacillin/tazobactam was lower against Pseudomonas sp., while some activity was demonstrated against some strains of Klebsiella. Good activity was seen not only against methicillin-susceptible (MS) staphylococci but also against some methicillin-resistant (MR) strains. In the latter, the combination of piperacillin/tazobactam was active only if the strains showed beta-lactamase production. These findings are interesting above all in regard to the synergistic effect demonstrated against MR beta-lactamase producing staphylococci and the Klebsiella-Enterobacter-Serratia (KES) group.  相似文献   
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