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101.
A case of hemangioendothelioma of the mandible, the third of its kind to involve the jawbone is reported. The radiological appearance of new bone formation is a unique feature in this case. The vascular malignant tumor has a poor prognosis.  相似文献   
102.
103.
Baroreceptor influences on cardiac-related sympathetic nerve activity   总被引:1,自引:0,他引:1  
We studied the effect of a dropped ventricular beat (i.e. loss of one cycle of pulse synchronous baroreceptor nerve activity) on the centrally generated 2-6 Hz oscillation in postganglionic sympathetic nerve discharge (SND) in cats anesthetized with Dial-urethane. The results indicate that in each cardiac cycle baroreceptor nerve activity can: (1) decrease the rate of recruitment and number of postganglionic fibers that become active and (2) advance the onset of central inhibition responsible for the abrupt decline of SND. These effects are independent of baroreceptor-mediated entrainment of the 2-6 Hz oscillation of SND to the cardiac cycle.  相似文献   
104.
The effect of 21 amino acids was studied on glycogen accumulation during sporulation in the blue-green alga Anabaena sp. All the amino acids enhanced the initial level of glycogen on the 4th day. The maximum amount of glycogen, on the 20th day, was noticed from l-methionine, l-tyrosine, glycine, and l-histidine supplemented cultures. Others like l-serine, l-valine, l-asparagine, dl-alanine, l-glutamic acid, l-phenylalanine, l-aspartic acid, l-arginine, and dl-lysine come next in the order. On the other hand, l-cysteine and l-cystine, although upto the 16th day they exhibited higher values of glycogen, did not show much variation in glycogen content over nitrogen-free medium. Except in these two amino acids, in all others initiation of sporulation occurred on the 4th day, resulting in free spores on the 8th day. But in case of l-serine, l-asparagine, l-isoleucine, and l-phenylalanine free spores were noticed only on the 12th day while in dl-lysine they were seen on the 16th day. l-cysteine and l-cystine supplemented media showed free spores on the 20th day as in nitrogen-free control.  相似文献   
105.
The organization within the descending sympathetic pathways on the surface of the dorsolateral funiculus of the spinal cord was investigated in anesthetized dogs. Changes in heart rate and carotid, renal, and femoral resistances were calculated during electrical stimulation of the descending spinal sympathetic pathways; the location within the pathway of the maximum change in each of these parameters was then determined. Blood pressure increased at each stimulation point with the maximum increase at 3-3.5 mm ventrolateral to the dorsolateral sulcus (DLS). The maximum increases in carotid, renal, and femoral resistances occurred with stimulation at 0.5-1.5, 2, and 3 mm ventrolateral to the DLS, respectively. Maximum heart rate responses were elicited by stimulation 2 mm ventrolateral to the sulcus. These data demonstrate that the pathway is organized in a dorsal-to-ventral manner, with the most rostral parts of the body being represented most dorsally and the more caudal parts being represented more ventrally.  相似文献   
106.
OBJECTIVES: The objectives of this study were to propose a method of calculating longitudinal limits of normal decline (LND) in forced expiratory volume in 1 second to identify individuals with an excessive decline in lung function and to compare the method with other published LND methods. METHODS: We used longitudinal data from 11 workplace-based spirometric monitoring programs conducted from 1987 to 2001 on 12,729 workers to evaluate effectiveness of each LND method in identifying a "true" excessive decline in forced expiratory volume in 1 second defined using two criteria: slope >60 mL/year or >90 mL/year estimated over 5 or more years of follow up. RESULTS: In comparison to the LND proposed by the American College of Occupational and Environmental Medicine, the proposed method had 5.0 to 2.7 times higher sensitivity over years 1 through 5 for the >60-mL/yr criterion. CONCLUSIONS: The proposed LND method was more effective than the other methods for identifying excessive declines.  相似文献   
107.
BACKGROUND: Individuals of low socioeconomic status (SES) are likely to have poor sleep and poor health. This study aims to evaluate whether and how much of the socioeconomic differences in health are explained by sleep. METHODS: The subjects were 3684 (2471 males and 1213 females) employees aged 20-65 working in local government in Japan. A questionnaire survey was conducted in January 2003. Analysis of covariance (ANCOVA) was performed to examine the association of employment-grade with sleep, measured by the Pittsburgh Sleep Quality Index (PSQI), and with health, measured by the Physical and Mental Component Summary Scales (PCS and MCS) of the Short Form-36 (SF-36). RESULTS: In men, higher grade employees had better sleep and better health. The age-adjusted difference between the highest and the lowest grade employees was 1.9 points (95% confidence interval = 1.0-3.0) in the PCS and 3.4 points (1.8-4.9) in the MCS. The grade difference in health reduced to 1.5 points (0.5-2.5) in the PCS (21.1% reduction) and 2.0 points (0.6-3.4) in the MCS (41.2% reduction), when the PSQI global score was adjusted for. The grade differences in sleep quality contributed more to the health inequalities than sleep quantity. Among women, no significant grade differences were observed in the PSQI global score. The grade differences in the PCS and MCS were weaker and less consistent than those of men, and the differences hardly changed when the PSQI global score was adjusted for. CONCLUSION: Sleep quality may mediate the relationship between SES and physical and, in particular, mental health in men.  相似文献   
108.
109.
A 54-year-old woman underwent mastectomy and axillary lymph node dissection for infiltrating ductal carcinoma with multiple lymph node involvement. The patient received adriamycin 60 mg/m(2) and cyclophosphamide 600 mg/m(2) (AC) followed by weekly paclitaxel 80 mg/m(2) and external irradiation to the local lymph node regions as adjuvant treatment. After 1 year and 5 months, the patient suffered her first recurrence, developing multiple brain and meningeal metastases. CNS involvement was well controlled by oral capecitabine (2400 mg twice daily, on days 1-21 of a 28-day cycle) and external whole brain irradiation of 50 Gy with minimal toxicity. We suggest that capecitabine contributed to the favorable clinical course in this patient and believe that, as an oral agent, this drug may benefit patients with CNS metastases of breast cancer by allowing home-based therapy.  相似文献   
110.
Cancers of the floor of the mouth and lower gingiva are treated by an approach combining external radiation treatment and interstitial implant with Iridium-192 radioisotopes. One technique to administer the dose to these areas is a “loop” technique. A major problem in edentulous patients is that the plastic loops housing the Iridium-192 sources slide out of place along the gum, resulting in loss of ideal spacing. When this occurs, dosimetry for the implant generated from localization films prior to loading does not reflect the distribution of dose delivered. To overcome this problem, we have devised polytetrafluoroethylene (PTFE) spacers which, when used between the loops, maintains their correct spacing. An implant technique and the spacers will be described.  相似文献   
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