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991.
Pennell RG; Baltarowich OH; Kurtz AB; Vilaro MM; Rifkin MD; Needleman L; Mitchell DG; Mervis SA; Goldberg BB 《Radiology》1987,165(1):79-83
Endovaginal ultrasound (US) was performed in 38 pregnant women at 5-12 menstrual weeks, when the initial transabdominal sonograms had been considered inconclusive or equivocal. Clinical follow-up disclosed 32 intrauterine pregnancies (12 living, 18 spontaneous incomplete abortions, and two embryonic demises) and six ectopic pregnancies. In the 32 intrauterine pregnancies (normal and abnormal), the correct diagnosis was made in all cases with endovaginal US. The endovaginal images demonstrated the intrauterine embryo, its heart motion, and the yolk sac more clearly and more often when these structures were not apparent on the transabdominal scans. Abnormal gestational sacs were better resolved. In the six cases of ectopic pregnancy, while an extrauterine ectopic sac was visualized in only three, absence of an intrauterine gestational sac was confirmed in all cases with endovaginal scanning. No endovaginal study yielded less information than its transabdominal counterpart. Endovaginal sonography is likely to be diagnostic when transabdominal images fail to yield a definitive diagnosis in early pregnancies. 相似文献
992.
本文用微型计算机对在手动式分光光度计上测得的吸收光谱数据进行处理,以导数光谱系数倍率法不经预先分离直接测定小儿退烧片中阿司匹林的含量,方法简便、快速,不需特殊仪器,易于推广。平均百分回收率为99.74±0.46(n=9)。同时还用双波长法测定了另一组分醋氨酚的含量,平均百分回收率为99.54±0.52(n=9)。结果满意,可用于多组分药物制剂的分析。 相似文献
993.
Morton JP Atkinson G MacLaren DP Cable NT Gilbert G Broome C McArdle A Drust B 《European journal of applied physiology》2005,94(5-6):541-548
The loss of the ability of skeletal muscle to generate force is one of the most appropriate and valid means to quantify muscle damage. Routine measurements of maximal muscle force, however, include many potential sources of error, the most important of which may be a possible lack of central drive to the muscles. The aim of the present study was to determine the reliability of maximal isometric quadriceps muscle force and voluntary activation over a timescale that is typically employed to examine the aetiology of exercise-induced muscle damage. We also attempted to characterise the reliability of several twitch interpolation variables including the size of the interpolated twitch and the state (i.e. unpotentiated vs potentiated) and size of the resting twitch. Over a 7-day period, eight healthy active males performed repeated maximal voluntary isometric contractions (MVC) of the quadriceps (baseline and 2 h, 6 h, 24 h, 48 h, 72 h and 7 days post). Systematic variations in maximal muscle force, voluntary activation, interpolated twitch, unpotentiated twitch and potentiated twitch were not statistically significant (P>0.05) and 95% repeatability coefficients of ±76.03 N, ±4.42%, ± 8.44 N, ±25.92 N and ±43.58 N were observed, respectively. These data indicate that young healthy well-familiarised male subjects can reproduce their perceived maximal efforts both within and between days where activation levels of >90% are routinely achieved. Providing activation remains within these limits in the 7 days following an acute bout of exercise, the researcher would be 95% certain that exercise-induced muscle damage is present in individual subjects (taken from similar subject populations) if MVC force falls outside these limits. 相似文献
994.
Image-guided surgical drainage of medial parapharyngeal abscesses in children: a novel adjuvant to a difficult approach 总被引:2,自引:0,他引:2
Cable BB Brenner P Bauman NM Mair EA 《The Annals of otology, rhinology, and laryngology》2004,113(2):115-120
Surgical drainage of localized infections in deep neck spaces in children is often completed without a high degree of technical difficulty. However, abscess drainage within the superior parapharyngeal space medial to the great vessels is particularly challenging for otolaryngologists. Drawbacks to both the intraoral and external approaches to this area have led us to develop a new adjunctive technique that utilizes intraoperative image-guided technology to augment the intraoral approach. Here we present a case series of 12 children in whom this technique was successfully used. 相似文献
995.
OBJECTIVE: Although the anticoagulatory properties of hirudin are well known, its direct vasoactive effects have not been investigated extensively. Hirudin stimulates nitric oxide and prostacyclin production in noncoronary vascular beds, but its actions on coronary arteries are unknown. MATERIALS AND METHODS: Five-millimeter segments of canine left circumflex coronary arteries were obtained for organ chamber experiments. Some segments were denuded of endothelium before study. Segments were exposed to hirudin (10(-10)-10(-6) mol/L) following precontraction with prostaglandin F(2alpha) with or without pretreatment with indomethacin or calcium channel blockers (verapamil and nifedipine). RESULTS: Hirudin stimulated endothelium-independent contraction in coronary arterial segments. Maximum tension (hirudin 10(-6) mol/L) above precontraction baseline was 33.6 +/- 9.0% (n = 10, P < 0.05) for endothelium-intact and 31.8 +/- 11.5% (n = 8, P < 0.05) for endothelium-denuded arterial segments. Differences between endothelium-intact and endothelium-denuded segments were not significant. Contractile responses to hirudin were unaffected by the presence of indomethacin. Pretreatment with either verapamil or nifedipine (10(-4) mol/L) for 1 h attenuated these contractions. The maximal increase in tension above baseline (hirudin 10(-6) mol/L) for verapamil and nifedipine was only 6.2 +/- 12.4 and 3.8 +/- 7.0% (n = 6, P < 0.05 versus endothelium-intact control), respectively. CONCLUSIONS: Hirudin stimulates endothelium-independent contractions of canine coronary arteries in vitro. Pretreatment with calcium channel blockers attenuates this response, suggesting that extracellular influx of calcium has an important mechanistic role in hirudin-mediated coronary artery constriction. 相似文献
996.
The mediastinal vessels in 27 patients who had previously undergone vascular surgery were evaluated with use of magnetic resonance (MR) imaging for patency and the presence of stenosis. Thirty-six postoperative vessels or shunts were studied, including 11 aortas after coarctation or stenosis repair, 18 systemic-pulmonary shunts, four pulmonary artery or vein repairs, and three spiral vein grafts. Angiographic (n = 21), direct surgical (n = 1), contrast material-enhanced computed tomography (n = 1), or clinical (n = 13) findings were correlated with the MR findings. Overall, the accuracy of MR imaging for determination of patency was 100%. In patients with angiographic correlation and technically adequate MR examinations, MR imaging results were used to identify or exclude stenoses correctly in 66.7% of patent vessels. The four missed or underestimated stenoses occurred in vessels 10 mm or less in diameter. 相似文献
997.
Glazer HS; Niemeyer JH; Balfe DM; Devineni VR; Emami B; Hayden RE; Aronberg DJ; Levitt RG; Ward MP; Sagel SS 《Radiology》1986,160(2):343-348
Untreated neoplasms of the neck (tumors of the oropharynx, supraglottic area, carotid body, and thyroid, in addition to malignant lymphadenopathy) were evaluated in 23 patients with magnetic resonance (MR) imaging. The results were compared with computed tomographic (CT) scans in 20 patients. Contrast between tumor and fat was best on relatively T1-weighted images (500/30-35 [TR msec/TE msec]), whereas separation of tumor and muscle was best with relatively T2-weighted pulse sequences (1,500/90). Balanced images (1,500/30-35) provided best overall image quality and best demonstrated vascular anatomy. MR imaging was usually superior to CT in showing the relationship of tumor mass to muscle. MR imaging and contrast material-enhanced CT were equivalent in most patients in defining vascular anatomy, but MR imaging was superior when intravenous contrast material was not administered. However, CT was more helpful in showing bone and cartilage anatomy, and in some patients CT also was better in showing airway abnormalities. Despite these limitations, MR imaging is a promising imaging technique for studying neoplasms of the neck. 相似文献
998.
999.
We conducted a phase II single-institution trial in a homogenous patient population with advanced non-small-cell lung cancer to determine whether changing the carboplatin schedule in the carboplatin/gemcitabine doublet would enhance tolerability and/or results. Thirty patients with stage IIIB (with malignant effusion) or stage IV disease received gemcitabine 1100 mg/m2, days 1 and 8 plus carboplatin at an area under the curve of 5 on day 8. Cycles were repeated every 28 days, up to 6 cycles. A response rate of 10% was demonstrated (none complete), but an additional 45% of patients had stable disease. The median time to progression was 5.8 months and the median survival was 8.3 months. A 1-year survival rate of 27% and a 2-year survival rate of 16% were seen. The main nonhematologic toxicity was non-neutropenic infection. Thrombocytopenia occurred in 8 patients (27%; 7 grade 3, 1 grade 4). Carboplatin/gemcitabine with a day 8 administration of carboplatin is well tolerated with a similar survival to established platinum-based doublets. 相似文献
1000.