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61.
 The purpose of this study was to investigate the possible pathways in the somatosensory system that relate to the postural reflexes in the leg muscles during a sudden, toes-up platform rotation. The inputs to the cutaneous mechanoreceptors in the sole of the foot as well as to the joint receptors in the ankle joint were modulated by standing on different supporting surfaces and by immobilizing the ankle joints; and three leg muscle responses (characterized by short latency, medium latency, and long latency) to the platform movement were recorded in 15 healthy young subjects. It was found that: (1) the short latency was not affected by the changes in either plantar pressure or ankle joint movement; (2) the medium latency was regulated by the plantar pressures under the foot, as sensed by the cutaneous mechanoreceptors in the sole of the foot, and by the ankle joint movement, as perceived by the joint receptors in the ankle joint; (3) the long latency was also related to the ankle joint movement, but this relation seems to be modulated by the plantar pressures under the foot; and (4) both medium and long latencies were well correlated with the time derivative of the pressure difference between the forefoot and the rear foot regions (r=0.7), as well as with the static pressure in the antagonist foot region (r>0.6). Received: 12 January 1996 / Accepted: 30 September 1996  相似文献   
62.
Although Hedgehog (HH) signaling plays a critical role in patterning the ventral midbrain, its role in early midbrain specification is not known. We examined the midbrains of sonic hedgehog (Shh) and smoothened (Smo) mutant mice where HH signaling is respectively attenuated and eliminated. We show that some ventral (Evx1+) cell fates are specified in the Shh-/- mouse in a Ptc1- and Gli1-independent manner. HH-independent ventral midbrain induction was further confirmed by the presence of a Pax7-negative ventral midbrain territory in both Shh-/- and Smo-/- mice at and before embryonic day (E) 8.5. Midbrain signaling centers are severely disrupted in the Shh-/- mutant. Interestingly, dorsal markers are up-regulated (Wnt1, Gdf7, Pax7), down-regulated (Lfng), or otherwise altered (Zic1) in the Shh-/- midbrain. Together with the increased cell death seen specifically in Shh-/- dorsal midbrains (E8.5-E9), our results suggest specific regulation of dorsal patterning by SHH, rather than a simple deregulation due to its absence.  相似文献   
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The association of hepatitis C virus (HCV) infection and tattooing was studied in 87 tattooed and 126 tattoo free healthy young men who did not engage in intravenous drug use or multiple sexual activity. Antibody against HCV (anti-HCV) was tested in serum specimens by enzyme immunoassay with C100-3, NS3, and core antigens; 11 of the 87 (12.6%) tattooed and 3 of the 126 (2.4%) tattoo free subjects were positive for anti-HCV (odds ratio = 5.9, 95% CI = 1.6-22.0). A relationship was demonstrated by an increased risk for HCV infection with an increasing number of tattooed site (P(trend) = 0.002). All but one of the 87 tattooed subjects had been infected by hepatitis B virus (HBV) and 25 were carriers of hepatitis B surface antigen (HBsAg). None of the 25 HBsAg carriers was positive for anti-HCV whereas 11 of the 62 HBsAg non-carriers had anti-HCV, suggesting a negative association between the HBsAg carriage and the long lasting anti-HCV (P = 0.02, Fisher's exact). The status of the tattooer was also an important determinant for HCV infection; the risk was higher if tattooing was done by a non-professional friend than by a professional tattooist. Tattooing, probably with improperly sterilized needles, can clearly pose an increased risk for HCV infection in Taiwan. This study indicates the need for legal standards for hygienic tattooing as part of preventive measures for the control of parenterally transmitted infections.  相似文献   
66.
The proliferative response of peripheral blood mononuclear cells (PBMC) to a recombinant non-structural (NS3) protein of hepatitis C virus (HCV) was studied in 41 patients with chronic hepatitis C. Of them, 28 had chronic persistent hepatitis (CPH) and 13 chronic active hepatitis (CAH). The positive proliferation rate of PBMC to the recombinant NS3 protein, T9Ag, was 66% in the 41 patients (77% in CAH versus 61% in CPH; P > 0.05) when stimulation index (SI) = 4 was set as the cut-off value. However, mean SI of CAH patients was significantly higher than that of CPH patients (8.3 +/- 5.2 versus 5.1 +/- 3.6; P < 0.05). Six other chronic hepatitis patients who were repeatedly negative for anti-HCV antibody but positive for serum HCV RNA also had an SI of > or = 4.0. The frequency of cellular immune response to the T9Ag is among the highest results obtained by using HCV antigens tested so far. Our studies thus indicate that NS3 is an immunologically important region of HCV for T cells. Moreover, the proliferative response to T9Ag may help to establish hepatitis C etiology in chronic hepatitis patients who are seronegative with currently available anti-HCV assays.  相似文献   
67.
BACKGROUND: Systemic anaphylaxis after the ingestion of mite-contaminated food has rarely been reported. OBJECTIVE: To describe an 8-year-old boy in whom systemic anaphylaxis developed shortly after the ingestion of pancakes prepared with commercial pancake flour. METHODS: The patient underwent skin prick testing for house dust mites and with uncontaminated and mite-contaminated pancake flour. Specific IgE for mites and the main ingredients of the pancake flour were also evaluated, with titers for Der p 1, Der f 1, and Blo t 5 quantitated using immunochemical methods. A sample of pancake flour was examined microscopically for mites. RESULTS: The patient had positive skin prick test results to contaminated pancake flour extract (1 g/5 mL), Dermatophagoides pteronyssinus, and Dermatophagoides farinae but a negative skin test response to uncontaminated pancake flour. The patient's serum specific IgE analysis was positive for antibodies to dust and storage mite allergens. There was no response, however, to the main ingredients of the pancake mix. Microscopic examination of the pancake flour revealed the storage mite Blomia freemani. Using an immunochemical assay, we found that the contaminated flour contained 5.4 microg/g of the allergen Blo t 5 but no Der p 1 or Der f 1. CONCLUSIONS: This patient's anaphylactic episode was the result of ingestion of the storage mite B. freemani. To our knowledge, this is the first reported systemic hypersensitivity reaction caused by this mite anywhere in the world.  相似文献   
68.
The effect of long-term alternate-day steroid administration on lymphocyte and polymorphonuclear cell (PMN) functions was studied in 10 steroid-dependent adult asthmatic patients. The duration of alternate-day prednisone usage ranged from 3 to 12 yr with an average of 6.7 ± 3.6 yr. Maintenance steroid dosage at the time of study ranged from 20 to 50 mg on alternate days, averaging 31 ± 8 mg. Prednisone caused marked lymphopenia, suppression of phytohemagglutin (PHA) lymphocyte transformation and PMN adherence 4 hr after ingestion. By 24 hr these measurements returned to normal or higher. These effects appeared at all doses between 20 and 50 mg of prednisone. In contrast, there was no statistically significant suppression of the total leukocyte count, total and active erythrocyte (E) rosette-forming lymphocytes, serum immunoglobulin concentrations, polymorphonuclear cell (PMN) phagocytosis, or delayed skin reactivity. We conclude that the acute effects of prednisone on lymphocyte and PMN function are transient and return to normal levels by 24 hr. The continued administration of beclomethasone dipropionate by inhalation did not interfere with the recovery of the transient leukocyte abnormalities induced by oral prednisone.  相似文献   
69.
BACKGROUND AND PURPOSE: Juvenile rheumatoid arthritis (JRA) is the most common form of arthritis in children and affects both quality of life and school attendance. Weather and temperature conditions are believed to affect joint pains; however, very few studies have investigated this issue. This study examined the association between joint pain in JRA patients and weather conditions. METHODS: The daily pain ratings of 52 patients previously diagnosed with JRA were recorded on visual analog scales over 4 months beginning January 1, 2004. These ratings were then compared with weather data to evaluate possible correlation between these two factors. RESULTS: Twenty nine patients kept daily records during the first 2 months. There was no positive correlation between weather parameters (such as temperature, humidity, and barometric pressure) and pain ratings. Interestingly, the pain rating significantly increased the day after the advent of a cold wave (sign test, p<0.01; Wilcoxon signed ranks test, p=0.001). The number of patients who experienced joint swelling was not related to weather conditions. Twenty one participants continued maintaining the diaries during the next 2 months. The patients reported higher pain levels in the first 2 months during the cold wave period than in the next 2 months when the cold wave period had ended (p<0.001). CONCLUSION: A dramatic weather change such as a sudden cold wave might influence the experience of joint pain.  相似文献   
70.
Kikuchi-Fujimoto disease (KFD) is a rare cause of cervical lymphadenitis which mostly affects Asian women but is sometimes observed in the pediatric population. This study analyzed the clinical manifestations and disease course in children with KFD. Retrospective chart review and telephone interview were used to collect data for 13 children (8 boys and 5 girls) with a diagnosis of KFD from January 1988 to January 2003. Involvement of the posterior cervical lymph nodes was found in 12 patients, leukopenia in 9, and all patients had C-reactive protein less than 5 mg/dL. A high antinuclear antibody titer was associated with a more protracted and complicated course. Five of the 13 patients had new symptoms compatible with an autoimmune process during follow-up, with neurological symptoms the most common. In conclusion, the risk of evolution into an autoimmune syndrome in pediatric KFD patients is high, and careful long-term observation is mandatory.  相似文献   
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