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101.
The triangular fibrocartilages (TFC) of 136 wrist joints from 48 fetuses and 20 infants fresh cadavers without any evidence of known deformity and injury were studied. Perforations of the TFC were found not only in infants (18.8%), but also in fetuses (25%). The difference between the incidences of the perforations in the two groups is not statistically significant (P > 0.05). Furthermore, we did not find that perforation of the TFC is correlated with either sex or side of wrists (P > 0.05). Histologically, the vascularity and cellularity of the TFC have no significant correlation with the absence or presence of perforation in it. We believe that, besides trauma, inflammation and degeneration, some perforations of the TFCs are congenital in origin, which all take the form of fissure and are located mainly in the radial half of the TFC.  相似文献   
102.
103.
The extracellular concentrations of dopamine (DA) and its metabolites, dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), in the striatum and the nucleus accumbens were measured in awake, freely-moving rats. Clozapine (20 mg/kg, i.p.) increased extracellular DA and HVA in both regions but increased DOPAC only in the striatum. Scopolamine (1 mg/kg), although it had no effect by itself in the striatum or nucleus accumbens, inhibited the ability of clozapine to increase extracellular DA, DOPAC and HVA concentrations in the striatum. The clozapine-induced increase in DA in the frontal cortex was not blocked by scopolamine. Haloperidol (1 mg/kg, i.p.) and thioridazine (10 mg/kg, i.p.) also increased extracellular DA, DOPAC and HVA in the striatum, but scopolamine pretreatment did not inhibit these increases. The results suggest that clozapine differs from haloperidol and thioridazine in that the effect of clozapine, but not that of the two neuroleptic drugs, to increase DA release in the striatum acutely depends on muscarinic receptor stimulation. These results suggest that clozapine, despite its strong muscarinic antagonist properties, does not produce full blockade of muscarinic receptors in vivo in the striatum. The interaction of clozapine with the cholinergic system in the striatum could be relevant to its lack of ability to produce extrapyramidal symptoms or tardive dyskinesia.  相似文献   
104.
105.
We report a case of a 63-year-old woman who presented with pseudoaneurysm of the free wall of the left ventricle secondary to myocardial infarction, in the presence of angiographically normal major coronary arteries. This is the only such case we know of, in which the patient underwent successful surgical correction. At last follow-up, the patient was in good condition with no evidence of cardiac disease, at 9 years after surgery.  相似文献   
106.
107.
No Heading We measured the slippage of 4He films adsorbed on Grafoil using the quartz-crystal microbalance (QCM) technique. The slippage of 4He films depended on the oscillating amplitude. In a large oscillating amplitude of a 5.0 MHz quartz crystal, 4He films underwent slipping gradually below a certain temperature. On the other hand, in a small oscillating amplitude, another additional increase appeared.PACS numbers: 67.20. +k, 81.40.Pq  相似文献   
108.
109.
The antacid properties of seven antacids listed in the hospital formulary of a medical center were evaluated with in vitro tests. These included not only the preliminary antacid test and acid-neutralizing capacity test as described in the United States Pharmacopeia (USP XXIII), but also a buffering pH profile test. The preliminary antacid test measured the final pH of a 10-mL solution of 0.5 N HCl 10 minutes after addition of the minimum recommended dose of an antacid, while the neutralizing capacity test measured the amount (mEq) of HCl neutralized by the minimum recommended dose in 15 minutes. The buffering pH profile recorded the pH time course of dynamic simulated gastric fluid neutralization by a dose of an antacid. In the preliminary antacid test, magnesium oxide showed the highest pH (9.52 +/- 0.14, mean +/- standard deviation, n = 3); aluminum phosphate gel yielded a final pH of 2.51 +/- 0.01, thus failing to meet the criteria of an antacid (pH > 3.5). In the acid-neutralizing capacity test, hydrotalcite had the highest neutralizing capacity (28.26 +/- 0.3 mEq), while sodium bicarbonate had the lowest (7.40 +/- 0.12 mEq). In the buffering pH profile test, aluminum-magnesium hydroxide suspensions and hydrotalcite tablets maintained a steady optimum pH (3-5) for around 1.5 hours. One tablet of calcium carbonate, sodium bicarbonate or magnesium oxide could not raise the gastric pH to above 3, but two tablets increased the pH excessively (5.3 to 8.6). The higher dose (two tablets) of aluminum hydroxide hexitol complex could not raise the pH to the optimal level. These findings demonstrate that there is disparity in the antacid effectiveness estimated by the neutralizing capacity test and the buffering pH profile test and suggest that the efficacy of an antacid cannot be accurately predicted from its acid-neutralizing capacity. The dose of antacids greatly influences the neutralizing pH profiles. Aluminum-magnesium compounds appear to provide steadier buffering than carbonate compounds or magnesium oxide.  相似文献   
110.
The authors have developed short-channel strained-silicon-on-insulator (strained-SOI) MOSFETs on silicon-germanium (SiGe)-on-insulator (SGOI) substrates fabricated by the Ge condensation technique. 35-nm-gate-length strained-SOI MOSFETs were successfully fabricated. The strain in Si channel is still maintained for the gate length of 35 nm. The performance enhancement of over 15% was obtained in 70-nm-gate-length strained-SOI n-MOSFETs. Fully depleted strained-SOI MOSFETs with back gate were successfully fabricated on SGOI substrate with SiGe layers as thin as 25 nm. The back-gate bias control successfully operated and the higher current drive was obtained by a combination of the low doping channel and the back-gate control.  相似文献   
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