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81.
The parasites of the red rockfish Sebastes capensis off northern Chile are described quantitatively for the first time and compared with those of congeneric species of the Northern Hemisphere as well as of other Chilean marine fishes. Sixteen species were recorded, including 8 ectoparasites (2 copepods, 2 isopods, 1 turbellarian, and 3 monogeneans) and 8 endoparasites (2 acanthocephalans, 3 digeneans, and 3 nematodes). The ectoparasites Lepeophtheirus chilensis and Caligus cheilodactylus, and the endoparasites Pseudopecoelus sp. and Corynosoma sp. were predominant. Eighty percent of the fishes harbored 3-6 parasite species. Four parasite genera new to the genus Sebastes were found in S. capensis, which also shares several parasite genera with its congeneric species from other geographic areas. However, in contrast to its congeners, S. capensis exhibits a lower helminth species richness, although when all the metazoan fauna is considered the species number and diversity are similar. When compared with other demersal fishes of the Chilean coast, S. capensis shows a high number of species and high parasite abundance. Diphtherostomum sp. and Gnathia sp. are new generic records for the parasite fauna of Chilean coast fishes and the finding of Paramicrocotyle sp., Neobenedenia melleni, and Interniloculus chilensis in this study represents a new geographical record for these parasites.  相似文献   
82.
In a multinational, population-based study from the five Nordic countries (Denmark, Finland, Iceland, Norway and Sweden), 2648 children below 15 y of age were diagnosed with acute lymphoblastic leukaemia (ALL) in the years 1981-1996. The annual incidence was 3.9/100000 children and was stable throughout the study period. The development from regional or national protocols to common Nordic treatment protocols for all risk groups was completed in 1992 through a successive intensification of therapy, based on multidrug chemotherapy including pulses of methotrexate in high doses and avoidance of cranial irradiation in most children. For children with non-B-cell ALL (n=2602), the event-free survival (p-EFS) increased from 0.53+/-0.02 (diagnosed 7/81-6/86) to 0.67+/-0.02 (7/86-12/91) to 0.78+/-0.02 (1/92-12/96). The corresponding p-EFS values at 5 y were 0.57, 0.70 and 0.78, respectively. The main improvements were seen in the group of children with non-high risk leukaemia, with 5-y p-EFS values increasing from 0.60 to 0.76 and 0.85 for the three periods. In high-risk patients, progress has been moderate, especially in children with high white blood cell values at diagnosis. During the last 5-y period, only 10% of the patients received cranial irradiation in first remission while 90% of the patients received high doses of cytostatic infusions (methotrexate isolated or combined with cytarabinoside) and multiple intrathecal injections of methotrexate as CNS-adjusted treatment without any indication of an increased CNS relapse rate.  相似文献   
83.
The efficacy of HSV-1 thymidine kinase (TK) and Escherichia coli cytosine deaminase (CD) suicide gene therapies as cancer treatments are currently being examined in humans. We demonstrated previously that compared to single suicide gene therapy, greater levels of targeted cytotoxicity and radiosensitization can be achieved in vitro by genetically modifying tumor cells to express CD and HSV-1 TK concomitantly, as a fusion protein. In the present study, the efficacy of the combined double suicide gene therapy/radiotherapy approach was examined in vivo. Nude mice were injected either s.c. or i.m. with 9L gliosarcoma cells expressing an E. coli CD/HSV-1 TK fusion gene. Double suicide gene therapy using 5-fluorocytosine (500 mg/kg) and ganciclovir (30 mg/kg) proved to be markedly better at delaying tumor growth and achieving a tumor cure than single suicide gene therapy, which used 5-fluorocytosine or ganciclovir administered independently. Importantly, double suicide gene therapy was highly effective against large experimental tumors (>2 cm3), reducing tumor volume an average of 99% and producing a 40% tumor cure. Moreover, double suicide gene therapy profoundly potentiated the antitumor effects of radiation. The results indicate that double suicide gene therapy, particularly when coupled with radiotherapy, may represent a highly effective means of eradicating tumors.  相似文献   
84.
We studied the sensitivity of human melanoma (Bro strain) xenografts to drugs of the nitrosoalkylurea (NAU) class: nitrosomethylurea (NMM), karmustin (BCNU), nimustin (ACNU), nitrulin, and ADEKO. High antitumor activity of NAM was shown when the drugs were applied not only at the early, but also at the late stages of tumor progression (tumor mass 400 and 1200 mg, respectively). The therapeutic effect of the drugs was estimated with the use of criteria characterizing the kinetics of tumor regression, increased life span, and survival of treated animals. After early administration of the drugs (Day 4 after tumor transplantation), 67% and 50% of animals survive under the influence of nitrulin and ACNU, respectively, while the rate of tumor regression increased in the sequence nitrulin < karmustin < NMM < ACNU. After late administration (11 days after tumor transplantation), NMM was most effective at increasing survival (35% of survived animals by 35 days of observation), while the rate of tumor regression increased in the sequence ADEKO < NMM < karmustin < nitrulin < ACNU.  相似文献   
85.
An infant presented with persistent epiphora after successful probing of the lacrimal system. Examination of the nose showed a cystic structure occluding lower portion of the lacrimal drainage system. In cases of recurrent obstruction, nasal examination and endoscopic marsupialization may help guide the clinician towards the most appropriate treatment.  相似文献   
86.
BACKGROUND AND OBJECTIVES: Laparoscopic pyelolithotomy was performed in a pelvic kidney with a large renal pelvis calculus. METHODS AND RESULTS: Laparoscopic pyelolithotomy was successfully performed in a pelvic kidney with an operative time of 310 minutes. The use of intraoperative fluoroscopy and a semi-automatic suturing device greatly facilitated the procedure. The patient's operative pain was managed with 3 doses of ketorolac; she resumed a regular diet the day after surgery, and was discharged on the first postoperative day. CONCLUSIONS: For patients with a large stone in the renal pelvis of an ectopic kidney, laparoscopic pyelolithotomy provides an effective approach.  相似文献   
87.
Phospholamban is a small membrane protein which can form cation selective ion channels in lipid bilayers. Each subunit contains a single, largely hydrophobic transmembrane helix. The helices are thought to assemble as a pentameric and approximately parallel bundle surrounding a central pore. A model of this assembly (PDB code IPSL) has been used as the starting point for molecular dynamics (MD) simulations of a system consisting of the pentameric helix bundle, plus 217 water molecules located within and at either mouth of the pore. Interhelix distance restraints were employed to maintain the integrity of the helix bundle during a 500 ps MD simulation. Water molecules within the pore exhibited reduced diffusional and rotational mobility. Interactions between the alpha-helix dipoles and the water dipoles, the latter aligned anti-parallel to the former, contribute to the stability of the system. Analysis of the potential energy of interaction of a K+ ion as it was moved through the pore suggested that unfavourable interactions of the cation with the aligned helix dipoles at the N-terminal mouth were overcome by favourable ion-water interactions. Comparable analysis for a Cl ion revealed that the ion-(pore + water) interactions were unfavourable along the whole of the pore, increasingly so from the N- to the C-terminal mouth. Overall, the interaction energy profiles were consistent with a pore selective for cations over anions. Pore radius profiles were used to predict a channel conductance of 50 to 70 ps in 0.2 M KCl, which compares well with an experimental value of 100 ps.  相似文献   
88.
The present studies have examined whether the neuropeptide galanin can modulate brain serotoninergic (5-HT) neurotransmission in vivo and, particularly, 5-HT1A receptor-mediated transmission. For that purpose, we studied the ability of galanin (given bilaterally into the lateral ventricle, i.c.v.) to modify the impairment of passive avoidance retention induced by the selective 5-HT1A agonist 8-hydroxy-2-(di-n-propyloamino)tetralin (8-OH-DPAT) when injected prior to training. This impairment appears to be mainly related to activation of 5-HT1A receptors in the CNS. Galanin dose-dependently (significant at 3.0 nmol/rat) attenuated the passive avoidance impairment (examined 24 h after training) induced by the 0.2 mg/kg dose of 8-OH-DPAT. This 8-OH-DPAT dose produced signs of the 5-HT syndrome indicating a postsynaptic 5-HT1A receptor activation. Furthermore, both the impairment of passive avoidance and the 5-HT syndrome were completely blocked by the 5-HT1A receptor antagonist WAY 100635 (0.1 mg/kg). Galanin (0.3 or 3.0 nmol) or WAY 100635 (0.1 mg/kg) failed by themselves to affect passive avoidance retention. 8-OH-DPAT given at a low dose 0.03 mg/kg, which presumably stimulates somatodendritic 5-HT1A autoreceptors in vivo, did not alter passive avoidance retention or induce any visually detectable signs of the 5-HT syndrome. Galanin (0.3 or 3.0 nmol) given i.c.v. in combination with the 0.03 mg/kg dose of 8-OH-DPAT, did not modify passive avoidance. The immunohistochemical study of the distribution of i.c.v. administered galanin (10 min after infusion) showed a strong diffuse labelling in the periventricular zone (100-200 microm) of the lateral ventricle. Furthermore, in the dorsal and ventral hippocampus galanin-immunoreactive nerve cells appeared both in the dentate gyrus and the CA1, CA2 and CA3 layers of the hippocampus. In the septum only endogenous fibres could be seen while in the caudal amygdala also galanin-immunoreactive nerve cells were visualized far away from the labelled periventricular zone. At the level of the dorsal raphe nucleus a thin periventricular zone of galanin immunoreactivity was seen but no labelling of cells. These results suggest that galanin can modulate postsynaptic 5-HT1A receptor transmission in vivo in discrete cell populations in forebrain regions such as the dorsal and ventral hippocampus and parts of the amygdala. The indication that galanin administered intracerebroventrically may be taken up in certain populations of nerve terminals in the periventricular zone for retrograde transport suggests that this peptide may also affect intracellular events.  相似文献   
89.
This study was initiated to assess which mix of early STD/HIV prevention interventions would potentially be effective, cost-effective and sustainable in Turkey; and to program an intervention sequence to maximize synergy among the interventions. During rapid assessment we: 1) reviewed past issues of 3 leading newspapers; 2) collected information on TV coverage; 3) interviewed key informants including taxicab drivers, hotel employees, grocery store owners, academicians in public health and law, investigators of STD/HIV and reproductive tract infections, and officials in the ministry of health; 4) reviewed available evidence on STD/HIV morbidity, sexual behavior patterns, migration patterns and same/opposite gender sex trade. We found: 1) discrepancies between decision makers' perceptions and social realities with respect to the epidemiology of sexual behavior and STDs, and the state of public health programs; 2) discrepancies between sexual practices and public expression regarding sexual practices; 3) economic, demographic, and political pressures in Turkey and in surrounding countries for the expansion of prostitution; 4) a sexual double standard and gender specific migration patterns which sustain a high demand for commercial sex; 5) patterns of health care seeking behaviors and provision of STD clinical services which indicate other STDs may play a very important role in spread of HIV infection; 6) an important mass media role in opinion formation; 7) consensual denial of risk for the majority based on beliefs embedded in machismo, nationalism and religion, and a resulting marginalization and externalization of STD/HIV risk; 8) high prevalence of syphilis among both Turkish and immigrant female prostitutes in Istanbul (early latent 8 and 13%; late latent 0 and 4%; previous history 9 and 22%) 9) and high rates of syphilis among male prostitutes (early latent 11%, late latent 21% and previous history 58%). We concluded that interventions should initially include, in the following order; 1) awareness raising for decision makers and opinion leaders including members of parliament and mass media; 2) awareness raising for members of the general population; 3) needs assessment and intervention development for sex workers; 4) training in HIV and other STDs for medical personnel; and 5) quality assurance and control for laboratory procedures for STDs/HIV.  相似文献   
90.
STUDY DESIGN: This is a case report. OBJECTIVE: To report and to examine the clinical findings and management of epidural cavernous hemangioma. SUMMARY OF BACKGROUND DATA: Spinal epidural cavernous hemangiomatous malformation is a very rare entity. Only 20 cases of this disease have been reported in the literature. METHODS: The case of a 20-year-old woman with spinal epidural cavernous hemangioma was reviewed. RESULTS: The clinical presentation, diagnosis, and therapy of this disease are discussed. CONCLUSION: The treatment of epidural hemangioma consists of total or subtotal excision of the lesion, depending on the relation of the lesion to the spinal cord.  相似文献   
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