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61.
四种口服头孢菌素的体外抗菌活性的比较研究 总被引:2,自引:0,他引:2
本文报道口服Cefixime对900株需氧菌和厌氧菌的体外抗菌作用,并与其它口服的头孢克罗、头孢羟氨苄和头孢氨苄进行了比较。Cefixime对链球菌具较强作用,但对葡萄球菌的作用较差;对肠球菌无效。对肠杆菌科细菌的抗菌活性四者之中以Cefixime最强。Cefixime对头孢氨苄耐药株仍具高度活性,其MIC均值可降低60~1200倍以上。绿脓杆菌、硝酸盐阴性杆菌、鲁氏不动杆菌和产碱杆菌对Cefixime和其它3种头孢菌素的敏感性均较差。四者对厌氧菌的作用除厌氧球菌外其抗菌活性都很弱。Cefixime对β-内酰胺酶稳定,口服吸收良好,抗菌作用强,是一个值得进行临床研究的口服头孢菌素。 相似文献
62.
M T Schechter P W Neumann M S Weaver J S Montaner S A Cassol T N Le K J Craib M V O'Shaughnessy 《AIDS (London, England)》1991,5(4):373-379
During 1989, 316 members of a cohort of homosexual men were tested for HIV-specific DNA by the polymerase chain reaction (PCR) using a pair of gag-region primers. Of 125 HIV-seronegative subjects, 123 (98.4%) were PCR-negative while 158 (82.7%) of 191 HIV-seropositive subjects were PCR-positive. Fewer of the 33 subjects who were seropositive and PCR-negative were at Centers for Disease Control (CDC) stage IV than the seropositive, PCR-positive subjects (6 versus 25%; P = 0.030). The seropositive, PCR-negative group had higher mean CD4 counts (640 versus 490 x 10(6) cells/l; P = 0.006), higher CD4: CD8 ratios (0.92 versus 0.64; P = 0.004), lower immunoglobulin (Ig) G levels (1290 versus 1645 mg/dl; P = 0.002), lower IgA levels (168 versus 251 mg/dl; P less than 0.001), and lower C1q binding activity (8 versus 14%; P = 0.010) than the seropositive, PCR-positive subjects. The median rate of CD4 cell decline in the 3 years preceding the PCR sample was less marked in the seropositive, PCR-negative group than the seropositive, PCR-positive group (-58 versus -77 x 10(6) cells/l per year; P = 0.028). To control for duration of infection, we restricted the analysis to the subgroups of 11 seropositive, PCR-negative subjects and 34 seropositive, PCR-positive subjects who had seroconverted earlier in the cohort study. Both subgroups had similar durations of infection, yet the same pattern of differences persisted.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
63.
Oguzkan Sürücü Ulrich Sure Sabine Gaetzner Sonja Stahl Ludwig Benes Helmut Bertalanffy Ute Felbor 《Child's nervous system》2006,22(11):1461-1464
Introduction and background A 3-year-old Bosnian girl with a large symptomatic brainstem and multiple supratentorial cavernous angiomas, who underwent neurosurgical treatment, is presented. As multiple cavernomas are more common in familial cases, genetic analyses and neuroradiological imaging were performed in the patient and her parents to see whether there was any evidence for inheritance. This information is important for genetic counseling and provision of medical care for at-risk relatives. Currently, no recommendation is available on how to manage these cases.Results Genetic analyses demonstrated a novel CCM1 frameshift mutation (c.1683_1684insA; p.V562SfsX6) in the child and the asymptomatic 27-year-old mother. Sensitive gradient-echo magnetic resonance imaging of the mother revealed multiple supratentorial lesions, whereas analogous imaging of the father showed no pathological findings.Conclusion This case exemplifies that seemingly sporadic cases with multiple lesions might well be hereditary and that presymptomatic genetic testing of family members may identify relatives for whom clinical and neuroradiological monitoring is indicated. 相似文献
64.
65.
L Le Marchand L N Kolonel J H Hankin C N Yoshizawa 《The American journal of clinical nutrition》1989,49(3):567-572
The relationship of alcohol use to diet was examined in 2272 male and 2337 female adults aged 45 y and older who provided a quantitative diet history during 1977-1979. Mean values for each dietary variable, adjusted for smoking, ethnicity, income, and education, were compared in each sex between abstainers and drinkers and by tertile of ethanol intake. Linear relationships with extent of drinking were also sought. Drinkers were found to be less obese than abstainers. Consumption of carbohydrate, vitamins, calcium, fruits, fruit juices, and raw vegetables was greater among abstainers whereas consumption of fat (particularly polyunsaturated fatty acids), cholesterol, zinc, meat, pickled vegetables, and dried fish was greater among drinkers. Because validations of dietary questionnaires have shown that alcohol consumption is more accurately recalled than food intake, the possibility of a residual confounding effect for these dietary variables should be considered in epidemiologic studies of alcohol and health. 相似文献
66.
Muriel Wisniewski Alain Le Borgne Nicolas Spassky 《Macromolecular chemistry and physics.》1997,198(4):1227-1238
The polymerization of lactides with various D /L enantiomeric compositions using achiral Schiff's base/aluminium methoxide as initiator (SALENAlOCH3) in dichloromethane solution at 70°C is reported. The conversion was kept below 70% in order to limit transesterification reactions. The polymers obtained after precipitation show a narrow molecular weight distribution (ratio of weight- to number-average molecular weights M w/M n = 1,1–1,2) and an optical rotation higher than that expected from the optical purity of the starting monomers. The examination of the thermal properties reveals that whatever their enantiomeric composition all the prepared polymers are crystalline. This unusual behavior is explained by an end-chain propagation mechanism producing stereocopolymers with long enantiomeric sequences, i.e., increased isotacticity as substantiated by an examination of the microstructure of the polymers by means of 13C nuclear magnetic resonance. A stereocomplex formation was observed for stereocopolymers with optical purities below 40%. 相似文献
67.
Jan Groetzner Ingo Kaczmarek Bruno Meiser Markus Müller Sabine Daebritz Bruno Reichart 《The Journal of heart and lung transplantation》2004,23(6):770-773
Chronic renal failure triggered by calcineurin inhibitor (CNI)-based immunosuppression is a common complication after cardiac transplantation. Sirolimus and mycophenolate mofetil (MMF) are 2 newer immunosuppressive agents with no documented nephrotoxic side effects. This case report describes a patient with ongoing chronic renal failure 10 months after cardiac transplantation on cyclosporine-based immunosuppressive therapy. Conversion of the immunosuppressive regimen from cyclosporine to sirolimus and MMF resulted in freedom from acute rejection, excellent cardiac graft function and consistently improved renal function. This case illustrates the beneficial potential of sirolimus and MMF as CNI-free and safe long-term immunosuppression in a patient with chronic renal failure after heart transplantation. 相似文献
68.
D Doummar B Roussat B Pelosse H Ducou Le Pointe M Iba-Zizen A Roubergue D Rodriguez T Billette de Villemeur 《Archives de pédiatrie》2004,11(11):1384-1388
Acute or rapidly progressive visual loss in children needs urgent attention and treatment. It may be unilateral orbilateral. Etiology depends upon the involved areas: eye ball, optic nerve, retro-chiasmatic pathways. Psychogenic origin is quite common in school-age children, however, it has to be considered last. Unilateral visual loss may be overlooked. Acute total transitory visual loss may be due to epilepsy or to migraine. Rapidly progressive visual loss may be due to retinal disease, optic neuritis or cortical blindness. Management of visual loss depends on clinical features, associated symptoms, and aspect of the optic disc. It needs collaboration between ophthalmologist,pediatrician and neuropediatrician. Retinal hemorrhages first call to mind a traumatic origin. Swelling of the optic disc may be due to increased intracranial pressure or due to optic neuritis. When the optic disc is normal it is necessary to rule out organic diseases before establishing the diagnosis of a psychogenic vision disturbance. In emergency, brain neuroimaging is the best way to diagnose intracranial mass and visualize optic pathways. 相似文献
69.
目的:探讨MRI对先天性胆脂瘤的诊断价值。方珐:回顾性分析7例经手术病理证实的先天性胆脂瘤的MRI表现,7例均为脑外型,其中6例胆脂瘤位于桥小脑角区,l例胆脂瘤位于脊髓内.结果:先天性胆脂瘤的绝大多数MRI表现为T1WI呈低信号,T2WI呈高信号,信号欠均匀,且病灶具有“见缝就钻”的特点。增强扫描,病灶无强化,但如合并感染可有轻度强化。结论:MRI的表现及特殊序列FLAIR、SPIR像的相互补充应用对先天性胆脂瘤的诊断及鉴别诊断具有重要意义。 相似文献
70.
Martin Krause Wolfgang Fogel Volker Tronnier Sabine Pohle Konstanze H?rtnagel Ute Thyen Jens Volkmann 《Movement disorders》2006,21(12):2255-2257
Pantothenate kinase-associated neurodegeneration (PKAN) is a rare autosomal recessive disorder with onset in childhood and rapid progression. There is no causative and insufficient symptomatic drug therapy. Deep brain stimulation (DBS) of the internal pallidum (GPi) has been reported to improve motor function. Most case reports, however, are limited to short observational periods. The impact of DBS on the progression and life expectancy in PKAN is unknown. We present a 5-year outcome and video documentation of bilateral GPi-DBS of an adolescent patient suffering from genetically defined PKAN. 相似文献