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141.
142.
T A Klein D G Young S R Telford R Kimsey 《Journal of the American Mosquito Control Association》1987,3(2):154-164
Lutzomyia vexator is an efficient experimental vector of Plasmodium mexicanum, infecting 69.2% (9/13) of the Sceloporus undulatus lizards with as few as one bite. Sporozoites were present in the salivary glands by day 6.5 postfeed and infective by day 8 postfeed at 27 degrees C. The prepatent period was relatively long, ranging from 23 to 40 days for bite-induced infections and appears to be related to the number of sporozoites injected. The acute phase of the infection is initially exponential and rapid. All lizards (6) that were not sacrificed, died of fulminating infections from 13 to 56 days after parasites were seen in the blood films. Gametocytes from 2 experimentally infected lizards were infective to L. vexator during the course of the acute infection. The majority of P. mexicanum parasites were in erythrocytes of Sc. undulatus. Exoerythrocytic forms were observed in circulating lymphocytes and thrombocytes, lymphocytes of spleen and bone marrow, and endothelial cells of brain capillaries. 相似文献
143.
C. Noonan M. Farrell J. Mullaney H. Cassidy M. A. Asghar B. J. Young Marie Hickey-Dwyer A. Patterson W. Power M. Hillery A. Benedict-Smith L. M. T. Collum S. Fitzsimon E. O’Donoghue R. Hitchings G. B. Arden A. O’Mahony A. Murray A. Whyte M. Shehata Hugh O’Donoghue Rosemary Robinson J. Toland P. Eustace 《Irish journal of medical science》1991,160(10):322-324
144.
Alterations of surfactant pools in fetal and newborn rat lungs 总被引:2,自引:0,他引:2
Preparation by the developing alveolar epithelium for the transition to air breathing and surfactant secretion at birth are critical components of neonatal survival. We combined morphometric analysis and biochemical assays of lung phospholipids to measure the amount and redistribution of lung surfactant during the perinatal period of rats. Within 10 min of the start of air breathing, there was a small increase in type II cell lamellar body content by morphometric and biochemical estimates. By 24 h, the whole lung and alveolar extracellular pool surfactant lipid had substantially increased. Subfractionation of the alveolar surfactant pool obtained at four times, from birth to 24 h of life, demonstrated a 20-fold increase in the ratio of phospholipid in a tubular myelin-rich fraction compared to a unilamellar vesicle-rich fraction. We conclude that packaging of surfactant may be very active immediately postbirth. Our results also indicate a major shift in the physical forms of extracellular surfactant during the first hours of air breathing. 相似文献
145.
Management of chronic lunotriquetral ligament tears 总被引:1,自引:0,他引:1
Treatment of chronic disruptions of the lunotriquetral (LT) ligament is not well-defined. Eleven patients treated by LT fusion with use of a compression screw are reported. The injury frequently resulted from hyperextension of the wrist. Pain on the ulnar side of the wrist, limited motion, and tenderness over the LT joint exacerbated by ballottement were present. Standard radiographs were normal. Arthrography showed the ligamentous tear in all cases. After operation, immobilization was continued until fusion was apparent radiographically. Fusion was achieved in all cases between 2 and 5 months. Four patients were free of pain, four patients had pain only at the extremes of motion, and three patients had persistent pain. Mean wrist motion was as follows (preoperative/postoperative): flexion (53 degrees/45 degrees), extension (60 degrees/49 degrees), radial deviation (17 degrees/21 degrees), and ulnar deviation (25 degrees/18 degrees). Maximum grip strength as a percentage of the uninjured side was 73% preoperatively and 59% postoperatively. LT tears can exist de novo or as part of the ulnar impaction syndrome; a method for differentiation is presented. 相似文献
146.
A R Young H S?veland J D Pickard S Perry L Brandt B Ljunggren 《Journal of cerebral blood flow and metabolism》1987,7(2):237-247
The acute vascular effects of tetraethylammonium chloride (TEA) were examined on annular segments of rabbit basilar arteries. Contractions induced by the potassium channel blocker were compared with those obtained for potassium chloride, 5-hydroxytryptamine (5-HT) and norepinephrine (NE). The greater magnitude of the contractions was of the following order: [K+] greater than 5-HT greater than TEA greater than NE. High concentrations of TEA alone (10(-2) M) generated spontaneous oscillatory contractions in cerebral vessels that were normally quiescent. Low concentrations of TEA (10(-8)-10(-6) M), which had no vasomotor properties per se, enhanced the contractile response of submaximal concentrations of 5-HT (10(-7) M) and NE (3 X 10(-6) M) and attenuated the contraction produced by 60 mM [K+]. An increased vascular response to the amines was still evident up to 3 h after the addition of TEA despite frequent rinsing with fresh buffer solutions. On arteries precontracted with TEA (10(-2) M), but not high [K+], the subsequent addition of 5-HT (10(-7) M) still induced a powerful constriction. Repeated concentration-response curves for [K+] were reproducible and, in the presence of TEA (10(-8) or 10(-6) M), the curve was displaced to the right in a competitive manner. A higher concentration of TEA (10(-4) M) was devoid of any blocking properties on the [K+]-induced response whereas, at 10(-3) M TEA, the response was potentiated, as evidenced by a shift of the curve to the left. Interactions between TEA and the cumulative response to 5-HT were difficult to interpret. Repeated exposures of the artery to 5-HT resulted in an increased maximal response with each determination (EAm = 127 +/- 9% and 149 +/- 14% of control values following the second and third applications, respectively). With TEA (10(-6) M), the increase in the maximal contractile effect noted previously was not observed. Contractions induced by single concentrations of TEA (10(-2) M) or [K+] (60 mM) were calcium dependent, were abolished completely in a calcium-free medium, and were depressed by the calcium antagonist nimodipine. 5-Hydroxytryptamine-induced contractions (10(-5) M) were less sensitive to withdrawal of calcium from the extracellular medium (31 +/- 6% relative to the maximal response at 4 mM calcium). Hence, an acute reduction in potassium conductance in cerebrovascular smooth muscle produced by TEA has complex, concentration-dependent effects and reproduces only part of the spectrum of effects of cisternal injection of blood on cerebrovascular reactivity. 相似文献
147.
148.
149.
Comparison of the APACHE III, APACHE II and Glasgow Coma Scale in acute head injury for prediction of mortality and functional outcome 总被引:1,自引:0,他引:1
Objectives: This study examines the efficacy of the predicting power for hospital mortality and functional outcome of three different
scoring systems for head injury in a neurosurgical intensive care unit (NICU).
Design: On the day of admission, data were collected from each patient to compute the Acute Physiology, Age, and Chronic Health
Evaluation (APACHE) II and III, and Glasgow Coma Scale (GCS) scores. Hospital mortality was defined as the deaths of patients
before discharge from hospital. Early mortality was defined as death before the 14th day after admission. Late mortality was
defined as death after the 15th day from admission. Functional outcome was evaluated by Index of Independence in Activities
of Daily Living (Index of ADL).
Setting: An 8-bed NICU in a 1270-bed medical center in Taichung Veterans General Hospital.
Patients and participants: Two hundred non-selected patients with acute head injury were included in our study in a consecutive period of 2 years.
Patients less than 14 years old were not included.
Interventions: None.
Measurements and results: Sensitivity, specificity and correct prediction outcome were measured by the chi-square method in three scoring systems.
The Youden index was also obtained. The best cut-off point in each scoring system was determined by the Youden index. The
difference in Youden index was calculated by Z score. A difference was also considered if the probability value was less than
0.05. The area under Receiver Operating Characteristic (ROC) curve was computed. Then the area under ROC of each scoring system
was compared by Z score. There was statistical significance if p was less than 0.05. For prediction of hospital mortality, the best cut-off points are 55 for APACHE III, 17 for APACHE II
and 5 for GCS. The correct prediction outcome is 82.4% in APACHE III, 78.4% in APACHE II and 81.9% in the GCS. The Youden
index has best cut-off points at 0.68 for APACHE III, 0.59 for APACHE II, and 0.56 for GCS. The area under Receiver Operating
Characteristic (ROC) curve is 0.90 in the APACHE III, 0.84 in the APACHE II and 0.86 in the GCS. There are no statistical
differences among APACHE III and II, and GCS in terms of correct prediction outcome, Youden Index and the area under the ROC
curve. Other physiological variables excluding GCS in APACHE III and II (AP III-GCS, AP II-GCS) have less statistical value
in the determination of mortality for acute head injury. For the prediction of late mortality, APACHE III and II yield significantly
better results in the area under the ROC curve, correct prediction and Youden index than those of GCS. Other physiological
variables (AP III-GCS and AP II-GCS) play an important role in the prediction of late mortality in APACHE scores. For prediction
of the functional outcome of surviving patients with acute head injury, the APACHE III yields the best results of correct
prediction outcome, Youden index and the area under the ROC curve.
Conclusion: The APACHE III and II may not replace the role of GCS in cases of acute head injury for hospital or early mortality assessment.
But for prediction of the late mortality, the APACHE III and II have better accuracy than GCS. Other physiological variables
excluding GCS in the APACHE system play a crucial contribution for late mortality. GCS is simple, less time-consuming and
economical for patients with acute head injury for the prediction of hospital and early mortality. The APACHE III provides
better prediction for severe morbidity than GCS and APACHE II. Therefore, the APACHE III provides a good assessment not only
for hospital and late mortality, but also for functional outcome.
Received: 22 May 1995 Accepted: 2 September 1996 相似文献
150.
David R. Young Lih-Yuann Shin Michael G. Rock Frank J. Frassica Petri Virolainen Edmund Y. S. Chao 《Journal of orthopaedic research》1997,15(5):773-780
The reconstruction of large bone and joint defects after the resection of malignant tumors remains a major challenge. Chemotherapy has significantly lowered the risk of metastasic disease, but complications associated with reconstructive techniques continue to result in late morbidity. In the present study, biomechanical torsion testing, gait analysis, and histomorphometric and scanning electron microscopic evaluations of 24 dogs were used to examine the effects of preoperative and postoperative administration of cisplatin on the biologic fixation of a porous-coated segmental replacement prosthesis. The chemotherapy consisted of four cycles of cisplatin administered at a dosage of 75 mg/m:2 preoperatively or postoperatively. The healing was enhanced by use of an autogenous corticocancellous bone graft. The graft was placed evenly around the prosthesis and the adjacent femoral cortex. Mechanical analyses of torsional stiffness, yield strength, and maximum strength revealed no statistically significant differences between the groups at 12 weeks. Such lack of difference was mainly due to the penetration of highly organized fibrous tissue into the porous surface; this provided strong fixation of the implant to bone even in the absence of bone ingrowth. Although bone ingrowth into the prostheses was not affected, electron microscopic, histomorphometric, and radiologic analyses showed a clear difference in the formation of new bone around the prosthesis. Preoperative chemotherapy did not alter the formation of new bone, but specimens from animals treated postoperatively with cisplatin showed significantly less bone graft resorption and less new bone formation. Hence, the effect of cisplatin administration caused only a temporary delay, not a permanent effect, on extracortical capsule formation. The formation of extracortical bone and soft tissue might prevent debris-incised osteolysis and, therefore, prevent late complications by forming a tight capsule around the bone-prosthetic interface. 相似文献