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81.
Abnormal motion of the interventricular septum is frequently observed after uncomplicated cardiac surgery. We sought to elucidate the mechanism underlying this phenomenon by using continuous echocardiographic imaging of the heart from a constant transesophageal location in 21 patients undergoing their first cardiac operation. Quantitative global and regional functional analyses were performed in each patient at baseline (stage 1), after median sternotomy (stage 2), after sternal retraction (stage 3), after pericardiotomy (stage 4), after completion of cardiopulmonary bypass (stage 5), and after chest closure (stage 6). During the first four surgical stages, mean left ventricular fractional shortening varied little among regions with a fixed reference system (maximum range, 31.6-39.2%; p = NS) but changed dramatically after the discontinuation of cardiopulmonary bypass (stage 5). The apparent medial hypokinesis that was observed (4.9 +/- 4.7% [SD]) was accompanied by lateral hyperkinesis (65.2 +/- 4.1%, p less than 0.0001). These regional differences were completely eliminated with a floating reference system (33.6 +/- 2.7% for medial, and 34.8 +/- 1.7% for lateral; p = NS), suggesting cardiac translation. Quantitative curvature analysis supported this conclusion, with preservation of baseline regional curvature seen throughout the procedure. The mean length of individual translational vectors (reflecting systolic movement of the endocardial centroid) remained minimal (less than or equal to 1.0 mm) through stage 4 but increased more than fourfold at stage 5, continuing in a medial direction after chest closure (5.2 +/- 3.0 mm and 271 +/- 6 degrees from anterior). Thus, abnormal postoperative septal motion is not caused by removal of restraining forces of the pericardium or anterior mediastinum but rather appears to be directly related to events occurring during cardiopulmonary bypass.  相似文献   
82.
Mice are a widely utilized in vivo model for translational salivary gland research but must be used with caution. Specifically, mouse salivary glands are similar in many ways to human salivary glands (i.e., in terms of their anatomy, histology, and physiology) and are both readily available and relatively easy and affordable to maintain. However, there are some significant differences between the two organisms, and by extension, the salivary glands derived from them must be taken into account for translational studies. The current review details pertinent similarities and differences between human and mouse salivary glands and offers practical guidelines for using both for research purposes.  相似文献   
83.
A method of growing rat Pneumocystis carinii with human embryonic lung fibroblasts (HEL-299 cells) sheeted onto microcarrier beads has been developed. This method allows production of large quantities of P. carinii organisms with very little contamination of host cells. A fivefold increase in the numbers of organisms was achieved, as determined by organism count, antigen detection, and DNA quantification. The majority of organisms produced by this method are trophozoites.  相似文献   
84.
85.
Objectives To compare objective voice measures of vocal stability during different speech tasks in women taking oral contraceptives to those in women not taking oral contraceptives. Methods Voice recordings obtained from 28 women, aged 20-30 years old, were used for the study. Eighteen of the women were taking some form of oral contraception at the time of the recording (OC women); ten women were not taking any oral contraceptive medication (NOC women). Measures related to pitch, vocal stability, and loudness were obtained from sustained vowel and paragraph reading tasks. Results The OC women demonstrated significantly higher pitch levels but lower values related to measures of vocal stability. Conclusions The use of oral contraceptives appears to exert a positive influence upon vocal fold function. Women taking oral contraceptives demonstrate higher pitch levels and greater stability during phonation than do women not taking oral contraceptives. This improvement in vocal function is contributed to the more stable hormonal environment that occurs with the use of oral contraceptives.  相似文献   
86.
OBJECTIVES: Although complications occur frequently after major lung resection, current predictive models are not entirely satisfactory. We devised a new predictive scoring system and compared it to two existing systems. METHODS: We performed an initial retrospective review of 400 patients who underwent major resection for lung cancer from 1980 to 1995. Predictive covariates (age, spirometry, diffusing capacity) associated with three or more complication groups were used to develop a scoring system. This system (EVAD) was then evaluated against the Physiological and Operative Severity Score for Enumeration of Mortality and Morbidity (POSSUM) and Cardiopulmonary Risk Index (CPRI) systems for patients operated between 1996 and 2001. RESULTS: Major resection for lung cancer included lobectomy (188) and pneumonectomy (30). Complication categories were: pulmonary (23; 10.5%); cardiovascular (24; 11.0%); infectious (8; 3.6%); other (29; 13.2%); nonfatal (45; 20.6%); and any (53; 24.2%). Death occurred in ten patients (4.6%). Mean EVAD scores were significantly different between groups with and without complications in all categories except infectious complications and death, whereas mean CPRI scores differed only for pulmonary complications, nonfatal complications, and death, and mean POSSUM scores did not appropriately differ for any complications. EVAD predicted incremental risk in all complication categories except cardiovascular, infectious, and death, whereas CPRI predicted incremental risk only for nonfatal and possibly any complications, and POSSUM did not predict incremental risk for any complication category. Receiver operating characteristic analysis demonstrated the EVAD system to be equivalent to or better than CPRI and POSSUM for all complication categories. CONCLUSIONS: A simple scoring system (EVAD) that utilizes pulmonary function test data and patient age predicts the likelihood of complications after major lung resection. It is easier to use and at least as accurate as other scoring systems currently in use.  相似文献   
87.
Osteomyelitis: detection with US   总被引:2,自引:0,他引:2  
Abiri  MM; Kirpekar  M; Ablow  RC 《Radiology》1989,172(2):509-511
To evaluate the role of ultrasound (US) in the detection of osteomyelitis, the authors prospectively studied 48 patients clinically suspected of having osteomyelitis. A sonographic diagnosis was made if fluid was seen directly in contact with bone, without intervening soft tissues. Twelve of the 48 patients were subsequently found to have osteomyelitis. In 10 of them, US demonstrated abnormal fluid adjacent to the bone. This fluid was thought to represent an inflammatory exudate dissecting in a subperiosteal and/or extraperiosteal location. Eight of the 48 patients had soft-tissue fluid collections. The rest of the patients either had no abnormalities or had cellulitis. The authors conclude that US can be useful in the detection of osteomyelitis.  相似文献   
88.
Trimetrexate and BW301U (piritrexim isethionate), lipid-soluble inhibitors of dihydrofolate reductase, are potent inhibitors of the growth of Pneumocystis carinii in culture with WI-38 cells. Inhibition was observed with 0.1 microgram of trimetrexate or BW301U per ml. Trimethoprim is ineffective at 100 micrograms/ml in this culture system. Both trimetrexate and BW301U were effective as prophylactic agents against P. carinii pneumonia in rats; trimetrexate at 7.5 mg/kg protected 9 of 10 rats, and BW301U at 5 mg/kg protected 4 of 10.  相似文献   
89.
研究发现银屑病皮损能够高度聚集原卟啉Ⅸ(PpⅨ,一种由5-ALA产生的内源性光源物质),但进行荧光诊断时却发现皮损内PpⅨ的分布存在差异,造成这种差异的原因目前尚不清楚。  相似文献   
90.
Objective: To investigate the diagnosis and surgical treatment of excessive lateral pressure syndrome of the patellofemoral joint caused by military training. Methods: Fifteen patients (patient group) and 18 healthy volunteers (control group) were involved in this retrospective study. Radiographs of the knee joints of all patients and volunteers were taken. The bone architecture was assessed, the trochlear angle, coincidence angle and patellofemoral joint index measured in both groups, and the resulting data compared. All 15 patients (17 knees) were treated by lateral collateral retinaculum release. Pre‐ and post‐operative pain was evaluated with a visual analog scale (VAS). Results: The differences between the two groups in coincidence angle (patient group: 7.67°± 5.81°; control group: ?2.2°±?2.71°) and patellofemoral joint index (patient group: 2.49 ± 1.40; control group: 1.25 ± 0.15) were statistically significant. Subchondral bone sclerosis and osteophytosis in the patellofemoral joint were more pronounced in the patient group than in the control group. The VAS was higher preoperatively (7.06 ± 0.85) than postoperatively (6 months postoperatively: 3.87 ± 0.24; 1 year postoperatively: 3.01 ± 0.17), and the differences between preoperative and postoperative were statistically significant. Conclusions: Apart from the case history, typical symptoms and physical signs, X‐ray examination is the most basic way to diagnose excessive lateral pressure syndrome of the patellofemoral joint, and the patellofemoral joint index is the most reliable for diagnosis. Lateral collateral retinaculum release with a small‐incision is an effective treatment for this disease.  相似文献   
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