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31.
Felipe Scalco Manzano DDSc Lucia Mercuri Granero MD Danilo Masiero MD Maria Teresa Botti Rodrigues dos Santos DDSc PhD 《Special care in dentistry》2004,24(4):235-239
This study was designed to verify the safety and efficacy of botulinum toxin type A (BTX-A) used as a neuromuscular block on spastic masticatory musculature of children with cerebral palsy. Six patients who had spastic-tetraplegic cerebral-palsy, aged 5 to 20 years were selected. All patients had spasticity of the jaw muscles, bruxism, lower lip trauma, limited mouth opening, and difficulties in cleaning the oral cavity. The patients were sedated under general anesthesia, while the dentist injected the masseter and temporalis muscles bilaterally with 150 and 75 units of BTX-A each. Clinical examinations were conducted at 7, 14, 30, and 90 days after the initial appointment. We found statistically significant decreases in muscle spasticity and bruxism ( p = 0.002), improved inter-incisal opening ( p = 0.002), improved oral hygiene ( p = 0.031), and less lower lip trauma ( p = 0.060) after the neuromuscular blocking. 相似文献
32.
Manohar Bance Alfredo Campos Lillian Wong David P Morris Rene van Wijhe 《Otolaryngology--head and neck surgery》2007,137(1):70-73
OBJECTIVES: The transmission of vibrations from the tympanic membrane to the stapes footplate by an ossicular reconstruction prosthesis is affected by the size of the prosthesis head. We sought to determine if augmenting or reducing the head size of prosthesis had a systematic effect on transmission of vibrations to the stapes. STUDY DESIGN: We conducted a fresh cadaveric temporal bone middle ear study. METHODS: The incus was replaced with a prosthesis using a tympanic membrane to stapes head (TASH)-type hydroxyapatite prosthesis in nine fresh cadaveric temporal bones. Three prosthesis head sizes were created: unaltered, reduced, and augmented. Stapes vibrations were measured with a laser Doppler vibrometer in response to acoustic frequency chirps at 90 dB SPL. RESULTS: All three head size prostheses resulted in smaller stapes vibrations than the intact ear. There was no difference in the vibration transmission between the three different head sizes. All prostheses showed a vibration loss of 10 to 15 dB compared to the intact ear. CONCLUSIONS AND SIGNIFICANCE: Within the range of sizes tested, prosthesis head size had little impact on vibration transmission to the stapes footplate. 相似文献
33.
Eighty-three isolates of ampicillin and chloramphenicol resistant Haemophilus influenzae were tested for susceptibility to fifteen antibiotics by the agar dilution method. Fifty-four were from paediatric patients with H. influenzae disease and 29 from nasopharyngeal carriers (pre-school children). Twenty-five strains belonged to serotype b, one to serotype a, one to serotype c and the rest were non-typable. All strains produced beta-lactamase and inactivated chloramphenicol in a rapid bioassay, suggesting the production of chloramphenicol-acetyltransferase. The most active drugs were ceftriaxone, cefotaxime, latamoxef, aztreonam and desacetyl-cefotaxime (MIC90: 0.03, 0.06, 0.12, 0.25 and 0.25 mg/l, respectively). Cefuroxime, rifampicin and imipenem (MIC90 1 mg/l), and the combination of amoxycillin and clavulanic acid (MIC90 2:1 mg/l), also showed good activity. Cefaclor, erythromycin, tetracycline, trimethoprim, sulfamethoxazole and cotrimoxazole were the least active of the drugs studied. The excellent in-vitro activity of the new beta-lactam agents against H. influenzae resistant to ampicillin and chloramphenicol offers a therapeutic alternative in the treatment of serious infections caused by these micro-organisms. 相似文献
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36.
Periodic lateralized epileptiform discharges: etiology, clinical aspects, seizures, and evolution in 130 patients. 总被引:4,自引:0,他引:4
Irene García-Morales M Teresa García Lucia Galán-Dávila Carlos Gómez-Escalonilla Rosana Saiz-Díaz Antonio Martínez-Salio Pilar de la Pe?a Julian A Tejerina 《Journal of clinical neurophysiology》2002,19(2):172-177
The purpose of this study was to analyze the clinical aspects in 130 patients presenting periodic lateralized epileptiform discharges (PLEDs) in their EEG and to compare these results with those found in the literature. Etiology, neurologic deficit, seizure occurrence, and evolution were studied in each patient by historical review. The recordings were obtained on 8- or 16-channel EEGs with electrode placement according to the International 10-20 System. Recordings containing PLEDs were selected. PLEDs were defined as repetitive periodic, focal, or hemispheric epileptiform discharges (spikes, spike and waves, polyspikes, sharp waves) usually recurring every 1 to 2 seconds. The statistical study was carried out via the chi(2) test using the computer program SPSS. The main etiology found in this group of patients was stroke (61 of 130 patients). Other processes found were brain infections, tumors, hematomas, and several other entities grouped together as miscellaneous (anoxic encephalopathy, subarachnoid hemorrhage, craniocerebral trauma, Creutzfeldt-Jacob disease, migraine, multiple sclerosis, and aminophylline intoxication). Half of these patients (65 of 130) developed seizures, mostly partial motor seizures. No significant relation between etiology and seizures was found (chi(2) = 2.81, P = 0.4222). Seizures recurred in 14 of 130 patients during a follow-up of 14.5 months. PLEDs were not recorded in any EEG at the time of seizure recurrence. PLEDs constitute a distinctive but uncommon EEG phenomenon of repetitive, periodic, and stereotyped lateralized complexes. In agreement with the literature, PLEDs were associated with an acute process and occurred early during the course of the illness in all patients studied and were usually associated with structural lesions, with stroke being the main etiology. Traditionally, seizures occur with PLEDs but it is also accepted that they can exist in patients who never develop epileptic activity, either clinically or electrically, as demonstrated in 50% of the patients studied. No significant association between seizures and any etiology could be found. It was not demonstrated that the occurrence of seizures may influence the outcome in any way. 相似文献
37.
The effects of chronic dietary protein restriction on ischemic renal failure were evaluated in rats subjected to 90 min of bilateral renal clamping. The rats were kept on either 20% casein (regular) diet or casein-free (protein-free) diet 10 days before and 21 days after renal injury. Rats on regular protein diet showed higher levels of BUN and serum creatinine and had a lower inulin clearance (microliter/min/100 g BW) than animals on protein-free diet (289 +/- 34 vs 582 +/- 103, p less than 0.05) 2 days after ischemia. However, the inulin clearance measured 21 days following ischemia was significantly higher in rats on regular diet (1468 +/- 181) than those maintained on protein-free diet after ischemia (560 +/- 167). When unilateral 90 min ischemia was performed in rats on regular diet, the postischemic kidneys showed an incomplete recovery of the inulin clearance (226 +/- 35) compared to the contralateral kidney (900 +/- 116), 21 days after ischemia; whereas in rats on a protein-free diet the inulin clearance averaged 106 +/- 17 in the postischemic kidney and 345 +/- 41 in the right kidney. When left renal ischemia and contralateral nephrectomy were performed, the inulin clearance was 1149 +/- 74 in rats on regular diet and 534 +/- 60 in rats on protein-free diet, 21 days following renal insult. These results suggest that protein restriction can play a protective role against renal ischemia in an initial phase, but it limits the late recovery from ischemia. The presence of a normal contralateral kidney inhibits the functional recovery of the postischemic kidney and a contralateral nephrectomy produces a compensatory functional hypertrophy of the postischemic kidney, even in rats on a protein-free diet. 相似文献
38.
Juan A. Rey M. Josefa Bello Ana M. Jimenez-lara Jesus Vaquero M. Elena Kusak Jos M. de Campos Jos L. Sarasa Angel Pestana 《International journal of cancer. Journal international du cancer》1992,51(5):703-706
Loss of constitutional heterozygosity as determined through the analysis of restriction-fragment-length polymorphism (RFLP) on tumoral and constitutional DNA has proven to be helpful to delimit the location of tumor-suppressor genes in the human genome. In malignant gliomas this approach indicates that chromosomes 9p, 10, 17p, and 22 may contain genes of this category involved in its origin and/or progression. Regarding chromosome 22, the data so far provided by molecular studies confirmed those previously reported by cytogenetic studies, suggesting the existence of a sub-group of malignant gliomas characterized by monosomy of this chromosome. However, the precise location of the putative glioma suppressor gene on chromosome 22 remains ambiguous. We have performed a combined cytogenetic and RFLP study on a series of 31 gliomas, looking for structural abnormalities of this chromosome. In 3 instances, terminal deletions of the long arm of chromosome 22 were observed by both methodologies, suggesting that the band q13 region distal to the D22S80 marker might be the critical domain non-randomly involved in tumor suppression of gliomas. 相似文献
39.
Lucia Carvalho Monica Lipay Francisco Belfort Ivan Santos Joyce Andrade Alessandra Haddad Flavia Brunstein Lydia Ferreira 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(9):961-968
BACKGROUND: Telomerase activity (TA) is believed to play a role in the regulation of senescence and to limit the number of cell divisions. The deregulation of telomerase appears to contribute to oncogenesis and the formation of immortal cell lines. As a result, it is believed that it could be used as a prognostic marker in melanoma. METHODS: TA was assayed by the polymerase chain reaction PCR-ELISA-based telomeric repeat amplification protocol (TRAP assay). One hundred and eight samples were distributed in four histological groups: 30 samples from primary cutaneous melanomas, 24 from peritumoural skin sites, 28 from benign melanocytic lesions, and 26 from normal skin sites as a control. RESULTS: TA was different among the four tested groups (Kruskall-Wallis test p<0.001), and increasing values of TA were observed progressing from normal skin to benign and then to malignant lesions. Among melanoma samples, there was a significant association between TA and ulceration (p=0.025), TA and vascular invasion (p=0.018) and TA and mitotic rate (p=0.029) (Mann-Whitney test). A linear regression analysis showed significant associations between the increase of TA with Breslow thickness (p=0.004) and the presence of satellites (p=0.002). CONCLUSIONS: We observed that TA had increased from control skin to peritumoural skin, and then to benign melanocytic lesions and finally to melanoma, suggesting tumour progression. TA showed higher values in the presence of some important histopathologic parameters related to poor prognosis in cutaneous melanoma such as ulceration, vascular invasion, satellites, high rates of mitosis, and in thicker tumours. 相似文献
40.
Functional Segregation of Color and Motion Processing in the Human Visual Cortex: Clinical Evidence 总被引:2,自引:2,他引:0
Anatomical and physiological investigations indicate two majordistinct functional streams within the extrastriate visual cortexof the macaque monkey, and behavioral observations suggest thatthe ventral (occipitotemporal) pathway is the cornerstone forobject recognition whereas the dorsal (occipitoparietal) pathwayis primarily involved in visuospatial perception and visuomotorperformance. In the context of this dichotomy we conducted apsychophysical and neuropsychological study of visual perceptualabilities in two stroke patients, each with lesions involvingseveral extrastriate areas. Magnetic resonance imaging demonstratedbilateral lesions; in one patient (E.W.) the lesion involvesthe ventral medial portions of the occipital and temporal lobes,and in the other (A.F.) the lesion involves dorsally the occipital-parietalarea, including the region of the temporal-parietal-occipitaljunction. E.W. suffers from achromatopsia of central origin,prosopagnosia, visual agnosia, and alexia without agraphia.His depth and motion perception, including recognition of movingobjects, are normal. He has superior visual field loss bilaterally,and slightly impaired acuity, and complains that the world appearsin a deep twilight even on a sunny day. In contrast, A.F. showsspecific deficits of stereopsis, spatial localization, and severalaspects of motion perception. He is also impaired at recognizingobjects presented from unconventional views, but recognitionof prototypical views of objects, and color and form discriminationare normal, as is his ability to recognize faces. The anatomical characteristics of the lesions of these two patientspermit a direct experimental comparison of the effects of lesionsconfined to the parietal or temporal pathways. E.W.'s and A.F.'sperformance on the psychophysical and neuropsychological tasksdiscussed here supports the functional distinction between adorsal and a ventral extrastriate system but additionally suggeststhe existence of a pathway involved in identification-from-motionthat is separate from both the dorsal early motion/spatial analysispathway and the ventral color/static-form pathway. 相似文献