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81.
This study investigates within-subject variations and associations of salivary viscosities and flow rates in a test panel of healthy adults. After several practice sessions, unstimulated and stimulated whole saliva samples were collected 5 times daily (at 0800, 1100, 1400, 1700, and 2000 h) from 30 university students. There was a significant within-subject variation in viscosity and flow rate of unstimulated saliva (P < 0.001). Intra-item correlations were significantly different for salivary flow rates (r = 0.82 for unstimulated, r = 0.88 for stimulated, P < 0.001) and viscosity of unstimulated saliva (r = 0.54, P < 0.05), but viscosity of stimulated saliva was different in this respect. Our results indicate that there is a significant within-subject variation in viscosity of unstimulated saliva.  相似文献   
82.
Background: The aims of the present study include: 1) to localize human neutrophil defensin‐1 (HNP‐1) through HNP‐3 in gingiva and in neutrophil extract‐treated epithelial cell monolayers; 2) to determine the effects of HNP‐1 on the epithelial cell viability, attachment, and spreading; and 3) to analyze the effect of HNP‐1 on the bacterial adherence to epithelial cells. Methods: For localization of HNP‐1 through HNP‐3 in gingival tissue and in preincubated cell monolayers, immunohistochemical and immunocytochemical methods were used. Viability and proliferation of epithelial cells were determined with commercial kits after incubating the keratinocytes with different HNP‐1 concentrations (low, 1 to 5 μg/mL; moderate, 10 μg/mL; high, 20 to 50 μg/mL). Attachment and spreading of keratinocytes on fibronectin‐coated surfaces in the presence of HNP‐1 were evaluated under microscope. Attachment of Fusobacterium nucleatum ATCC25586 and Prevotella intermedia ATCC25611 on keratinocytes preincubated with HNP‐1 were determined with a standard antibiotic test. Results: HNP‐1 through HNP‐3 localized in the junctional epithelium of clinically healthy gingiva and in the pocket epithelium of gingiva with periodontitis. When keratinocyte monolayers were incubated with neutrophil extracts, HNP‐1 through HNP‐3 were bound to the periphery of the growing cell colonies. In low HNP‐1 concentrations, the keratinocyte proliferation enhanced. Moderate and high concentrations of HNP‐1 increased the cellular death significantly. HNP‐1 increased the attachment and spreading of keratinocytes on fibronectin‐coated surfaces and bacterial attachment to keratinocytes in a concentration‐dependent manner. Conclusion: HNP‐1 plays a role in the integrity of keratinocytes by stimulating their proliferation, attachment, and spreading, whereas higher doses increase the bacterial attachment and keratinocyte death.  相似文献   
83.
Trimethoprim-sulfamethoxazole (TMP/SMX) is used in children with acute lymphoblastic leukemia (ALL) to prevent Pneumocystis pneumonia (PCP). We explored to which extent TMP/SMX influenced methotrexate (MTX)/6-mercaptopurine (6MP) dosage, myelosuppression, and event-free survival (EFS) during maintenance therapy. Of 447 study patients treated by the NOPHO ALL92 protocol, 120 patients received TMP/SMX continuously for 2-7 d/wk (TMP/SMX(2-7) ) and 287 patients never received TMP/SMX (TMP/SMX(never) ). Ten patients (all TMP/SMX(never) ) developed PCP, eight of which occurred within 7 months from the start of maintenance therapy. The TMP/SMX(2-7) group received lower oral 6MP doses than TMP/SMX(never) patients (50.6 vs. 63.9 mg/m(2) /d; P<0.001) but had lower absolute neutrophil counts (ANC) (median 1.7 vs. 2.0 × 10(9) /L; P<0.001). In Cox multivariate analysis, higher ANC levels (P=0.04) and male gender (P=0.06) were related to reduced EFS. ANC had no effect on EFS among TMP/SMX(2-7) patients (P=0.40) but did for TMP/SMX(never) patients (P=0.02). The difference in the effect on EFS between TMP/SMX(2-7) and TMP/SMX(never) patients was not significant (P=0.46). EFS did not differ between TMP/SMX(2-7) and TMP/SMX(never) patients (0.83 vs. 0.83; P=0.82). These results suggest that TMP/SMX is effective in preventing PCP and may have an antileukemic effect. TMP/SMX should be given the entire duration of maintenance therapy.  相似文献   
84.
The purpose of the current study was to evaluate influences of radial tears and partial meniscectomy of lateral meniscus on the knee joint mechanics during normal walking by using computational modeling. A 3D geometry of a knee joint of a healthy patient was obtained from our previous study, whereas the data of normal walking were taken from the literature. Cartilage tissue was modeled as a fibril reinforced poroviscoelastic material, whereas meniscal tissue was modeled as a transverse isotropic elastic material. The realistic gait cycle data were implemented into the computational model and the effects of radial tears and partial meniscectemy of lateral meniscus on the knee joint mechanics were simulated. Middle, posterior, and anterior radial tears in lateral meniscus increased stresses by 300%, 430%, and 1530%, respectively, at the ends of tears compared to corresponding areas in the model with intact lateral meniscus. Meniscus tears did not alter stresses and strains at the tibial cartilage surface, whereas partial meniscectomy increased contact pressures, stresses, strains and pore pressures in the tibial cartilage by 50%, 44%, 21%, and 43%, respectively. Increased stresses and strains were observed primarily during the first ~50% of the stance phase of the gait cycle. The present study suggests that anterior radial tear causes the highest risk for the development of total meniscal rupture, whereas partial meniscectomy increases the risk for the development of OA in lateral tibial cartilage. Highest risks for meniscus and cartilage failures are suggested to occur during the loading response and mid‐stance of the gait cycle. In the future, the present modeling may be further developed to offer a clinical tool for aid in decision making of clinical interventions for patients with knee joint injuries. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1208–1217, 2013  相似文献   
85.
86.
The necessity for postoperative inhaled nitric oxide (NO) therapy and predictive factors for that need were retrospectively analysed in 457 paediatric patients at risk of pulmonary hypertensive events following open-heart surgery for congenital heart disease. Inhaled NO was given postoperatively to 46% of the study group and to 23% of all patients undergoing open-heart surgery during the study period. Factors associated with increased need for postoperative NO were age &lt;1 year, Down's syndrome, preoperative pulmonary hypertension and increased pulmonary vascular resistance. Using a multivariate model based on these factors, 73% of the patients who were given NO were identified. Thus, in a setting with unrestricted access to NO therapy, almost half of the patients with cardiac lesions that commonly give rise to postoperative pulmonary hypertension were given postoperative NO. Seventy-three percent of postoperative NO treatment was associated with a relatively small number of pre- and perioperative patient-related risk factors.  相似文献   
87.
We report how scapholunate (SL) lesions found during arthroscopy were treated using a new palmar operation based on the use of a tendon loop formed using the palmaris longus tendon, with promising preliminary results. Scapholunate instability induced by hyperextension injury was diagnosed and graded arthroscopically. Volar capsuloplasty was then done by free tendon graft in the same session in 31 patients with grades II-IV scapholunate instability. Half of the patients operated on had a normal range of movement, and all except one had flexion-extension of at least 75% of the normal. Half of the patients had no pain or limitations of the use of the wrist, and although half the patients had some pain on exertion, not one had severe pain. These results are comparable to, or even better than, those reported using other methods of repair. The combined procedure saves money, diminishes the total recuperation time and, as autologous tissues are used for the repair, secondary operations for removal of the implant are unnecessary. This method seems to be a useful adjunct to the types of operative treatment available, although it is apparently not suitable in static grade IV SL instability.  相似文献   
88.
89.
The aim of this study was to investigate the prevalence of mental disorder and associated factors during an economic recession. Random samples of Finnish general population were collected in 3 consecutive years, 1993-95. The prevalence of mental disorders was assessed by means of the 12-item General Health Questionnaire (GHQ). The prevalence of mental disorders varied among Finnish men from 15.6% to 19.2% and among women from 21 to 24.5%. Mental disorder was more common among women than among men in every study year. Mental disorder was more common among the unemployed than among other respondents both in women and men in every year. Subjective poor health, suicidal thoughts and poor economic situation were constantly associated with mental disorder in both sexes every year. Using logistic regression analyses, problems with a partner, uncertain future orientation and use of psychoactive drugs, in particular, were found to be fairly permanent independent risk factors in relation to mental disorder. As studied by gender no major changes occurred in the mental health status of Finns during economic recession, although in many specific groups mental disorder was markedly more common than in the general population.  相似文献   
90.
Bipolar disorder is frequently connected to other psychiatric disorders. On the basis of The National Hospital Discharge Register in Finland, we studied the recorded prevalence of psychiatric comorbidity among bipolar inpatients by clinicians, and the factors that were associated with it. Of the 2687 hospital stays in 1998, 82% had no other recorded psychiatric diagnosis except an episode of bipolar disorder. Psychiatric comorbidity was recorded in 18% of hospital stays, of which 20% had two comorbid psychiatric diagnoses. Substance-related disorders (11%) were the most commonly recorded comorbid disorders. Personality disorders were recorded in 6%, and anxiety disorder in 1% of the hospital stays. These figures should be considered far below the expected ones. Recorded comorbidity was associated with the type of episode. Comorbidity in bipolar disorder in psychiatric hospitals in Finland seems to go greatly undetected and may have a deteriorating impact on the course of the illness.  相似文献   
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