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101.
We describe the postnatal development of the electroretinogram (ERG) receptoral response in the guinea pig. In addition, the
time course and nature of maturation was compared between albino and pigmented strains to consider the role that melanogenesis
might have in this process. Electroretinograms were collected on groups of albino and pigmented animals from postnatal day
(PD) PD1 to PD60. A-wave amplitudes and implicit times were extracted from filtered data (0–75 Hz). Receptoral components
were modelled using the delayed gaussian model of Hood and Birch [1] fitted as an ensemble to the raw data. Guinea pigs show
saturated amplitudes (RmP3) that are 50% of adult values at birth, these mature by PD12. Receptoral delay (td) also undergoes some postnatal maturation, while phototransduction gain (log S) is adult-like at birth. Albino animals had
significantly (p<0.05) larger RmP3 and log S across all ages. Guinea pigs have significant postnatal development in their receptoral response. Maturation of
RmP3 implies a postnatal increase in rod outer segment length. Whereas the adult values of log S implies a mature phototransduction
process at birth. We argue that the likely cause for the larger log S of albino eyes is compatible with theories of increased
levels of internal light. Whereas the larger RmP3, even after allowing for increased light effectiveness, may reflect a lower ocular resistance in albino eyes due to their
lower levels of melanin. Furthermore, decreased RmP3 and log S with age is observed in the pigmented group only and is consistent with increased ocular resistance due to melanin
development in this strain.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
102.
Three 1,2-benzothiazine derivatives were synthesized, and their analgesic/anti-inflammatory efficacy and their effects on gastric irritation were evaluated. Among the three compounds, 39 exhibited the most potent analgesic action, but the effect was weaker than that of piroxicam. Nonetheless, the compound showed 4 times more potent analgesic action with less gastric damage than did ibuprofen. These compounds did not show anti-inflammatory effect at an oral dose of 5 mg/kg. 相似文献
103.
A recombinant Escherichia coli expressing the Neurospora crassa metallothionein gene (NCP) has previously been shown to remove low levels of Cd and other metals from solution. For further development as a biosorbent, the encapsulation of the NCP is investigated by various matrices. The NCP was encapsulated in alginate, chitosan-alginate or kappa-carrageenan, and its physical properties characterized. Results indicated that encapsulation in alginate resulted in fragile beads, whereas encapsulation in kappa-carrageenan or chitosan-alginate provided more physical and chemical integrity to the beads. Maximal heavy metal removal by cells encapsulated in carrageenan occurred within 3 h, while a gradual increase in removal was observed up to 24 h for cells encapsulated in chitosan-alginate. Metal removal by cells encapsulated in alginate beads was lower than those encapsulated in carrageenan or chitosan-alginate. 相似文献
104.
Olafsson S Berstad A Bang CJ Nysaeter G Coll P Tefera S Hatlebakk JG Hausken T Olafsson T 《Alimentary pharmacology & therapeutics》1999,13(5):651-659
BACKGROUND: We have consistently achieved about 90% eradication of H. pylori with liquid bismuth, metronidazole and oxytetracycline. AIM: To test eradication and adverse events of ranitidine bismuth citrate (RBC) when given with metronidazole and either oxytetracycline or spiramycin. METHODS: One hundred and eighty-three patients were randomized to one of four 10-day regimens: RBC400OM: RBC 400 mg b.d., oxytetracycline 500 mg q.d.s.; RBC400SM: RBC 400 mg b.d., spiramycin 1 g q.d.s.; RBC200OM: RBC 200 mg q.d.s., oxytetracycline 500 mg q.d.s.; RBC200SM: RBC 200 mg q.d.s., spiramycin 1 g q.d.s. Additionally, all patients received metronidazole 400 mg q.d.s. A 14C-urea breath test was performed at 8 weeks. RESULTS: Intention-to-treat eradication rates were 94%, 91%, 94% and 89% with RBC400OM, RBC400SM, RBC200OM and RBC200SM, respectively (P = 0.81). Eradication was significantly higher in ulcer patients (97%) than in those with diagnoses other than ulcer (86%) (P = 0.009). There was a strong tendency to better eradication among those who had never smoked (100%) compared with ex-smokers (93%) and smokers (89%) (P = 0.06). Fifty-three per cent experienced at least one moderate or severe adverse event, and women had more adverse events than men (P = 0.0002). CONCLUSIONS: All four regimens had comparable efficacy and adverse events. Eradication was significantly better in ulcer patients but there was a trend to better eradication in those who smoked less, used less alcohol and exercised more. Adverse events were frequent, perhaps because of the large dose of metronidazole used, but few patients stopped treatment. 相似文献
105.
Oh Kee Kwon Kyu-Chang Wang Chong Jai Kim In-One Kim Je G. Chi Byung-Kyu Cho 《Child's nervous system》1996,12(10):633-636
Primary spinal cord primitive neuroectodermal tumor (PNET) is a rare entity. In all, 13 cases have been reported in the literature, including 3 with intracranial seeding. A 3-month-old girl with involvement of the spinal cord below the mid-thoracic level is described. The brain MRI revealed findings indicative of seeding along the intracranial subarachnoid space. Biopsy, duraplasty and removal of laminotomy flap were done. In spite of a good response to the first cycle of postoperative 8-drugs-in-a-day chemotherapy, further treatment was refused. She died 21 days after the onset of leg weakness, which reveals the rapid progression of untreated cases. To our knowledge, this is the first case of spinal cord PNET with parenchymal involvement that has been described in an infant. 相似文献
106.
107.
Tore Solheim Magne Lorentsen Per Kristian Sundnes Gisle Bang Lasse Bremnes 《International journal of legal medicine》1992,104(6):339-345
Summary With 158 victims, the fire on board the Scandinavian Star was one of the world's worst ferry disasters. A team of identification experts, including dentists, were employed to secure evidence for identification and to remove the victims from the ferry. Four parallel teams, each with 2 dentists, examined and autopsied the victims at the Institute of Forensic Medicine, University of Oslo. Using the INTERPOL Disaster Victim Identification forms and aided by computers, all victims were identified within 17 days. Dental identity could be established in 107 cases (68%). 相似文献
108.
The extracts of sixty Korean plants were evaluated for their biological activities such as antitumor activities against Sarcoma 180, Leukemia SN-36 and Ehrlich ascites carcinoma, antimicrobial activities and behavioral observation in mice. The results are tabulated. 相似文献
109.
目的 研究老年人脑梗塞继发性癫痫的发生率及发作时间 ,发作类型 ,癫痫发作与病变部位的关系、治疗与转归。方法 总结分析 5 6例老年人脑梗塞继发癫痫的临床、CT资料。结果 癫痫病发生率 9 0 % ;分别为早期癫痫与迟发性癫痫 ,而以迟发性癫痫为主 3 9例 (70 9% ) ;发作类型以局限运动为发作为主 3 6例 (64 9% ) ;癫痫发作与病变部位有关 ,病变多位于大脑半球叶 42例 (75 9% ) ,而以额叶为主。结论 老年人脑梗塞继发癫痫发病率高 ,经抗癫痫药物治疗 ,绝大多数能控制 相似文献
110.
George A Bang RL Lari AR Gang RK Kanjoor JR 《Burns : journal of the International Society for Burn Injuries》2000,26(4):409-413
The toxic effects of a gas depend on the time of exposure, concentration and its chemical nature. Pressurized liquids and gases exert an additional cold thermal injury and this may complicate the clinical picture. A patient who had an accidental exposure to liquid ammonia over a prolonged period, manifesting in cutaneous, respiratory and ocular damage in addition to a severe cold thermal injury (frostbite) with a fatal outcome is presented. The patient had flaccid quadriparesis and episodes of bradycardia, which has not been reported previously. These manifestations raise the possibility of the systemic toxicity in patients with prolonged exposure to ammonia. 相似文献