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21.
Although behavioral and neuropsychological data regarding the existence of images for odors are inconclusive, reconsideration of earlier EEG work provides reasonably clear evidence for an inner nose. However, further EEG studies and neuroimaging data seem essential for conclusive demonstration of an inner nose.  相似文献   
22.
A 5-year-old girl with an asymptomatic posterior mediastinal cyst from birth was followed with repeated echocardiograms. The cyst developed communication with the bronchus spontaneously around 8 months of age without clinical symptoms. This was detected from the sudden disappearance of the mass on echocardiogram, and an unusual air-pocket on chest roentgenogram. Computed tomography (CT) of the chest confirmed the diagnosis of communicating bronchogenic cyst (BC). She was treated successfully with complete surgical excision of the cyst and closure of the defect in the bronchus. We emphasize that surgery is indicated in all mediastinal BCs because of potential complications.  相似文献   
23.
A comparative study was conducted to evaluate the efficacy of a metal or flexible plastic 8 mm cannula for artificial abortion by vacuum aspiration for patients at six to 10 weeks' gestation. Complication rates, amounts of retained tissue (obtained with a curette check), frequencies of cannula obstructions and procedure times were used as criteria for determining the efficacy of the two types of cannulae. Two physicians participated in the study: one was responsible for the preliminary examination and performance of the abortion, and the other physician, who was kept unaware of the type of cannula used, was responsible for patient care after completions of the abortion to the time of the follow-up visit. Paracervical block anesthesia was used in all cases. Differences in complication rates (controlled for gestational age) between groups of subjects aborted with either the metal or flexible plastic cannula were not significantly different (p less than .05). For both patient groups shock was the most frequently reported immediate complication (2.7% in the metal cannula group, 4,7% in the flexible plastic cannula group), and leukorrhea was the most frequently reported complication at the time of follow-up (3.3% metal, 5.3% flexible plastic). Amounts of retained tissue and frequency of cannulae obstruction were similar for both groups. Procedure times were also similar for both groups (means of 5.7 minutes and 5.5 minutes, respectively, for procedures performed with the metal and flexible plastic cannulae).  相似文献   
24.
The concentrations of ammonia in the plasma of the mudskipper Boleophthalmus boddaerti exposed to cyanide for 1-6 days were significantly greater than the respective values of the controls. This was due to an increase in the production of NH3 in the muscle and an increase in the retention of NH3 and/or NH4+ in the blood of the cyanide-exposed fish when compared to controls. Cyanide exposure significantly increased the specific activity of muscle AMP deaminase. Since adenylosuccinate synthetase and lyase were also present in the muscle, exposure to cyanide might increase the production of NH3 from the catabolism of purine nucleotides. B. boddaerti exposed to cyanide excreted significantly less ammonia than the control fish. Results indicate changes in the permeability of the epithelial surfaces of the cyanide-exposed fish to NH3 and/or NH4+. Since the tissues and organs needed time to activate the inducible cyanide detoxification mechanisms, the increase in the production of NH3 might be an important defensive mechanism for B. boddaerti during the early phase of cyanide exposure.  相似文献   
25.
To determine whether platelets play a part in the pathogenesis of transient cerebrovascular ischemia, we studied 22 patients with transient ischemia, 18 control patients and 38 normal subjects. Platelet aggregation and [14C]-serotonin release by ADP, epinephrine and collagen were normal in all patients, as were plasma coagulation assays, except for shortened partial thromboplastin times in the patients with transient ischemia. Platelet coagulant activities concerned with initiation and early stages of intrinsic coagulation were increased two to three times in 12 patients with transient ischemic attacks with normal serum lipids and normal in the 10 others with Type IV hyperlipoproteinemia. These results indicate an association between platelet coagulant hyperactivity and transient ischemic attacks in a group of patients with normal serum lipids.  相似文献   
26.
A strain of Escherichia coli was constructed which had a complete deletion of the chromosomal uncB gene encoding subunit a of the F0F1-ATP synthase. Gene replacement was facilitated by a selection protocol that utilized the sacB gene of Bacillus subtilis cloned in a kanamycin resistance cartridge (Ried, J. L., and Collmer, A. (1987) Gene (Amst.) 57, 239-246). F0 subunits b and c inserted normally into the membrane in the DeltauncB strain. This observation confirms a previous report (Hermolin, J., and Fillingame, R. H. (1995) J. Biol. Chem. 270, 2815-2817) that subunit a is not required for the insertion of subunits b and c. The DeltauncB strain has been used to characterize mutations in Arg-210 and Glu-219 of subunit a, residues previously postulated to be essential in proton translocation. The aE219G and aE219K mutants grew on a succinate carbon source via oxidative phosphorylation and membranes from these mutants exhibited ATPase-coupled proton translocation (i.e. ATP driven 9-amino-6-chloromethoxyacridine quenching responses that were 60-80% of wild type membranes). We conclude that the aGlu-219 residue cannot play a critical role in proton translocation. The aR210A mutant did not grow on succinate and membranes exhibited no ATPase-coupled proton translocation. However, on removal of F1 from membrane, the aR210A mutant F0 was active in passive proton translocation, i.e. in dissipating the DeltapH normally established by NADH oxidation with these membrane vesicles. aR210A membranes with F1 bound were also proton permeable. Arg-210 of subunit a may play a critical role in active H+ transport that is coupled to ATP synthesis or hydrolysis, but is not essential for the translocation of protons across the membranes.  相似文献   
27.
BACKGROUND: Salbutamol is the most widely prescribed short acting beta 2 agonist and salmeterol is the first long acting inhaled beta 2 agonist. The dose equivalence of salmeterol and salbutamol is disputed. Estimates of weight-for-weight dose ratio have ranged from 1:2 to 1:16. A study was undertaken to clarify the true dose ratio. METHODS: The bronchoprotection afforded against repeated methacholine challenge by inhaled salmeterol 25 micrograms and 100 micrograms and salbutamol 100 micrograms and 400 micrograms was compared in a randomised, double blind, placebo controlled, crossover trial. Subjects were 16 stable asthmatics with a baseline forced expiratory volume in one second (FEV1) of > or = 65% predicted, screening concentration provoking a fall in FEV1 of 20% (PC20FEV1) of < or = 8mg/ml, and a shift in PC20FEV1 of more than two doubling concentration steps following inhalation of salbutamol 400 micrograms. On five separate occasions subjects underwent methacholine challenge before and 30 and 120 minutes after drug administration. PD20FEV1 was calculated for each challenge. FEV1 at 90 minutes after drug administration was also recorded. RESULTS: Bronchoprotection afforded by salmeterol was increased at 120 minutes compared with 30 minutes and protection by salbutamol was decreased. Protection by both doses of salmeterol was similar to salbutamol 100 micrograms at 30 minutes but significantly greater at 120 minutes. FEV1 at 90 minutes was significantly greater after salmeterol 100 micrograms than after placebo, but there were no other significant differences between treatments. Maximal observed protection was equivalent for salmeterol 100 micrograms and salbutamol 400 micrograms. CONCLUSIONS: The data are compatible with a weight-for-weight dose ratio for salmeterol:salbutamol of < or = 1:4.  相似文献   
28.
Computerized tomograms were studied of 67 adults whose lumbar pneumoencephalograms were normal or showed ventricular dilatation with or without widening of the sulci. The maximum ventricular area, measured from 80 x 80 matrix printouts, correlates well with measures of ventricular size on the pneumoencephalogram. An area of 10 cm2 is suggested as the upper limit of normal. The correlation between measures of sulcal width on computerized tomography and pneumoencephalography is less precise, but normal sulci and gross degrees of cortical atrophy can be identified.  相似文献   
29.
30.
The hemolytic action of the chlorine-containing pesticides, trichloroacetic acid (TCA), pentachlorophenolate (PCP), chlorophos and pentachloronitrobenzene (PCNB) on red cells was studied, as were their effects on acetylcholinesterase activity and resistance of red cells to mechanical hemolysis by ultrasound. The modifying action of pesticides on red cell membranes was shown to lead to their mechanical resistance. TCA, PCP and chlorophos were found to sensitize red cells whereas PCNB to make them resistant to the mechanical action of ultrasound. The kinetic characteristics of the structural functional disorders of red cells might be used as quantitative criteria of the efficacy of the action of pesticides on the cells.  相似文献   
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