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101.
A technique for safer and more effective pulsed laser lithotripsy of urinary and biliary calculi was investigated in vitro. The technique involves enclosing the distal end of the laser delivery fiber in a "plasma shield." The plasma shield is a specially designed metal cap that serves to transfer the laser-induced mechanical impulse to the calculus while shielding surrounding tissue from direct laser exposure and thermal radiation. The metal cap also offers the advantage of effectively blunting the sharp fiber tip and improving its visualization under fluoroscopy. Plasma shield lithotripsy using a 200 micron quartz fiber inserted into a section of a modified 0.034 in. diameter stainless steel guide wire was tested in vitro on a variety of calculi and compared with results obtained using a 200 micron laser fiber applied directly. Calculi tested included cystine, struvite and calcium oxalate dihydrate urinary stones and pigmented cholesterol gallstones. The laser source was a flashlamp-pumped dye laser producing pulses of 1.2 microsecond duration and operated at a wavelength of 504 nm and pulse repetition frequency of 5 Hz. The results show that plasma shield lasertripsy is as effective as direct lasertripsy for fragmenting gallstones, struvite and calcium oxalate dihydrate calculi, is potentially safer, and can fragment cystine calculi which the pulsed dye laser applied directly cannot. 相似文献
102.
Ensuring data quality in a multicenter clinical trial: remote site data entry, central coordination and feedback 总被引:1,自引:0,他引:1
J B Severe N R Schooler J H Lee G Haas K T Mueser P Rosen D Shortell M Shumway 《Psychopharmacology bulletin》1989,25(3):488-490
In an ongoing multicenter clinical trial, "Treatment Strategies in Schizophrenia," the five participating sites have the capacity to perform a variety of tasks or study functions independently. These tasks include (a) verification of diagnostic eligibility through the use of computerized decision algorithms; (b) assignment of patients to treatment based on prognostic indicators using a computerized randomization algorithm; (c) entry of data into a microcomputer using a clinical trial data management system that performs simple range and missing data item checks; and (d) regular transfer of all data to the central coordinating team. The clinical trial data management system employed allows for both independent site functioning and assurance of consistency across sites. The integration of a variety of software outside the main data management system provides the central coordinators with the tools to monitor critical data as it is collected, as well as the capacity to assess the flow, quality, and uniformity of the ongoing trial. 相似文献
103.
Effects of chemical mediators of anaphylaxis on ciliary function 总被引:2,自引:0,他引:2
Adam Wanner M.D. David Maurer Ph.D. William M. Abraham Ph.D. Zsolt Szepfalusi Marek Sielczak M.D. 《The Journal of allergy and clinical immunology》1983,72(6):663-667
We assessed the effects of selected chemical mediators of anaphylaxis on CBF in vitro. Ciliated epithelial cells were obtained from the trachea of conscious sheep with a cytology brush and suspended in a perfusion chamber containing KH. Ciliary activity was viewed microscopically and recorded on videotape for subsequent slow-motion analysis of CBF. Prostaglandin E1 (10(-8) M to 10(-6) M), prostaglandin E2 (10(-10) M to 10(-6) M), and leukotriene-C4 (10(-8) M) increased CBF between 7% and 33%. Histamine caused ciliostimulation only at the relatively high concentrations above 10(-5) M (7% increase in CBF), whereas prostaglandin F2 alpha (10(-10) M and 10(-6) M) was without effect. In no preparation was ciliary discoordination observed. These findings indicate that several chemical mediators of anaphylaxis stimulate CBF and that the previously described impairment of mucociliary transport in stable allergic asthma or antigen-induced bronchoconstriction is probably not caused by a primary alteration of ciliary function. 相似文献
104.
Atypical sexual behavior during sleep 总被引:5,自引:0,他引:5
OBJECTIVE: This article reports a case series of atypical sexual behavior during sleep, which is often harmful to patients or bed partners. METHODS: Eleven subjects underwent clinical evaluation of complaints of sleep-related atypical sexual behavior. Complaints included violent masturbation, sexual assaults, and continuous (and loud) sexual vocalizations during sleep. One case was a medical-legal case. Sleep logs, clinical evaluations, sleep questionnaires, structured psychiatric interviews, polysomnography, actigraphy, home electroencephalographic monitoring during sleep, and clinical electroencephalographic monitoring while awake and asleep were used to determine clinical diagnoses. RESULTS: Atypical sexual behaviors during sleep were associated with feelings of guilt, shame, and depression. Because of these feelings, patients and bed partners often tolerated the abnormal behavior for long periods of time without seeking medical attention. The following pathologic sleep disorders were demonstrated on polysomnography: partial complex seizures, sleep-disordered breathing, stage 3 to 4 non-rapid eye movement (REM) sleep parasomnias, and REM sleep behavior disorder. These findings were concurrent with morning amnesia. CONCLUSIONS: The atypical behaviors were related to different syndromes despite the similarity of complaints from bed partners. In most cases the disturbing and often harmful symptoms were controlled when counseling was instituted and sleep disorders were treated. In some cases treatment of seizures or psychiatric disorders was also needed. Clonazepam with simultaneous psychotherapy was the most common successful treatment combination. The addition of antidepressant or antiepileptic medications was required in specific cases. 相似文献
105.
106.
Renal oxalosis and azotemia after methoxyflurane anesthesia 总被引:4,自引:0,他引:4
107.
G. Chadi A. M?er L. Rosen A. M. Janson L. A. Agnati M. Goldstein S.-O. ?gren R. F. Pettersson K. Fuxe 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,97(1):145-158
Basic fibroblast growth factor (bFGF, FGF-2) is a trophic factor for neurons and astrocytes and has recently been demonstrated in the vast majority of dopamine (DA) neurons of the ventral midbrain of the rat. Potential neuroprotective actions of FGF-2 in the l-methyl-4-phenyl-l,2,3,6-tetrahydropyridine (MPTP) model have also been reported. The actions of the FGF-2 have now been further analyzed in a combined morphological and behavioural analysis in the MPTP model of the adult black mouse, using a continuous human recombinant FGF-2 (hrFGF-2) intraventricular (i.v.t.) administration in a heparin-containing (10 IU heparin/ml) mock cerebrospinal fluid (CSF) solution. Tyrosine hydroxylase (TH) immunocytochemistry in combination with computer assisted microdensitometry demonstrated a counteraction of the MPTP-induced disappearance of neostriatal TH-immunoreactive (ir) nerve terminals following the FGF-2 treatment. Unbiased estimates of the total number of nigral TH ir neurons, using stereological methods involving the optical disector (Olympus), showed that the MPTP-induced reduction in the number of nigral TH ir nerve cell bodies counterstained with cresyl violet (CV; by 56%) was partially counteracted by the FGF-2 treatment (by 26%). The behavioral analysis demonstrated an almost full recovery of the MPTP-induced reduction of the locomotor activity after FGF-2 treatment. This action was maintained also 1 week after cessation of treatment. The hrFGF-2 produced an astroglial reaction as determined in the lateral neostriatum and in the substantia nigra (SN) far from the site of the infusion, indicating that the growth factor may have reached these regions by diffusion to activate the astroglia. Immunocytochemistry revealed FGF-2 immunoreactivity (IR) in the nuclei of the astroglia cell population in the dorsomedial striatum and the microdensitometric and morphometric evaluation demonstrated an increase in the number, but not in the intensity, of these profiles on the cannulated side, suggesting the possibility that hrFGF-2 stimulates FGF-2 synthesis in astroglial cells with low endogenous FGF-2 IR. These results indicate that hrFGF-2, directly and/or indirectly via astroglia, upon i.v.t. infusion exerts trophic effects on the nigrostriatal DA system and may increase survival of nigrostriatal DA nerve cells exposed to the MPTP neurotoxin. 相似文献
108.
Infections with certain types of papillomaviruses, e.g., human papillomavirus type 16 (HPV-16), often progress to cancer. Malignant lesions associated with the closely related HPV-11 are extremely rare. Additionally, HPV-11 DNA, unlike HPV-16, does not normally transform cells in vitro. We determined that HPV-11 DNA was able to transform baby rat kidney cells in a ras-dependent focus assay when the upstream regulatory region (URR) was present in two copies. Addition of a second HPV-11 URR or an HPV-16 URR was equally effective and was position and orientation independent. The transformation was enhanced by dexamethasone. On passage the HPV-11 genome was not retained at a detectable level. This analysis supports isolated observations in vivo that duplications of regulatory sequences in HPV-11 increase the transformation potential of this virus type. 相似文献
109.
Ammonium perchlorate (AP) and sodium chlorate (SC) have been detected in public drinking water supplies in many parts of the United States. These chemicals cause perturbations in pituitary-thyroid homeostasis in animals by competitively inhibiting iodide uptake, thus hindering the synthesis of thyroglobulin and reducing circulating T(4) (thyroxine). Little is known about the short-term exposure effects of mixtures of perchlorate and chlorate. The present study investigated the potential for the response to a mixture of these chemicals on the pituitary-thyroid axis in rats to be greater than that induced by the individual chemicals. Adult male F-344 rats were exposed, via their drinking water, to the nominal concentrations of 0.1, 1.0, 10 mg/L AP or 10, 100, 1000 mg/L SC and their mixtures for 7 days. Serum T(4) levels were significantly (p < 0.05) reduced in rats following exposure to the mixtures, but not after exposure to the individual chemicals. Serum T(3) (triiodothyronine) was not altered by treatment and TSH (thyroid stimulating hormone) was only increased after the high-dose chlorate treatment. Histological examination of the thyroid gland showed colloid depletion and hypertrophy of follicular epithelial cells in high-dose single chemical and all mixture-treated rats, while hyperplasia was observed only in some of the rats treated with mixtures (AP 10 + SC 100, AP 0.1 + SC 1000, and AP 10 + SC 1000 mg/L). These data suggest that short-term exposure to the mixture of AP and SC enhances the effect of either chemical alone on the pituitary-thyroid axis in rats. 相似文献
110.
Contribution of redox-active iron and copper to oxidative damage in Alzheimer disease 总被引:1,自引:0,他引:1
Castellani RJ Honda K Zhu X Cash AD Nunomura A Perry G Smith MA 《Ageing research reviews》2004,3(3):319-326
Metal-catalyzed hydroxyl radicals are potent mediators of cellular injury, affecting every category of macromolecule, and are central to the oxidative injury hypothesis of Alzheimer disease (AD) pathogenesis. Studies on redox-competent copper and iron indicate that redox activity in AD resides exclusively within the neuronal cytosol and that chelation with deferoxamine, DTPA, or, more recently, iodochlorhydroxyquin, removes this activity. We have also found that while proteins that accumulate in AD possess metal-binding sites, metal-associated cellular redox activity is primarily dependent on metals associated with nucleic acid, specifically cytoplasmic RNA. These findings indicate aberrations in iron homeostasis that, we suspect, arise primarily from heme, since heme oxygenase-1, an enzyme that catalyzes the conversion of heme to iron and biliverdin, is increased in AD, and mitochondria, since mitochondria turnover, mitochondrial DNA, and cytochrome C oxidative activity are all increased in AD. These findings, as well as studies demonstrating a reduction in microtubule density in AD neurons, suggest that mitochondrial dysfunction, acting in concert with cytoskeletal pathology, serves to increase redox-active heavy metals and initiates a cascade of abnormal events culminating in AD pathology. 相似文献