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991.
文章对33例中老年肺尖和锁骨下区慢性结核作平片和肺尖断层对照分析。结果表明:断层对该部位慢性结核多形态病灶检出率和病情判断明显优于平片。着重对空洞、结核球和合并肺癌断层影像研究。肯定断层诊断价值。 相似文献
992.
D. Dickerson B. Adams G. Engelbrecht G. Boltman R. Hickman D. Kahn 《Transplant international》1992,5(Z1):S63-S64
The precise cause of allograft dysfunction after renal transplantation often cannot be established by non-invasive means. In clinical practice, radionuclide scans form an integral part of the clinician's armamentarium in the assessment of these patients [1, 2]. Unfortunately, in the clinical setting more than one pathological process may be responsible for the impaired function, making it difficult to correlate the scan appearances with the pathology. In this study in rats we compared the renal DTPA scan appearances of the various pathological processes which may cause renal allograft dysfunction in the immediate post-transplant period. 相似文献
993.
A 65-year-old male patient with an 8-year history of poliostotic Paget’s disease complained of shoulder pain that started
6 months prior to admission. An extensive lytic area was identified in the right proximal humerus along with Paget’s disease.
There was cortical destruction and a soft tissue mass. Following an incisional biopsy, a diagnosis of grade 2 chondrosarcoma
associated with Paget’s disease was made. The histologic identification of chondrosarcoma associated with Paget’s disease
is rare. However, the presence of a calcified matrix in a destructive lesion associated with Paget’s disease should alert
the radiologist and the pathologist to the possibility of a chondromatous differentiation taking place in the sarcoma associated
with Paget’s disease. The histologic evaluation of the lesion will form the basis for the diagnosis. 相似文献
994.
A. J. M. BALM B. B. R. KROON F. J. M. HILGERS A. JONK W. J. MOOI 《Clinical otolaryngology》1994,19(2):161-165
A lymph node metastasis in the neck or parotid region from an unknown primary melanoma is an uncommon occurrence. Out of a total of 300 patients with head and neck melanoma treated at the Netherlands Cancer Institute between 1976 and 1992, 17 (5.7%) presented in this way. The most common site for metastatic lymph nodes (18 nodes in 17 patients) was level V (n= 7), followed by the parotid region (n= 4), level II (n= 4), level III (n= 2), and level IV (n= 7). Two patients had local excision of the neck node metastasis only, while the remaining 15 patients underwent more extensive surgical treatment. The 5-year disease-specific survival rate in this group was 48%, with a median survival of 36 months, which is more or less similar to the prognosis of stage II melanoma of the head and neck with a known, surgically treated primary tumour. No relation was found between disease-free interval and sex, the number of positive lymph nodes or the duration of symptoms. 相似文献
995.
同型半胱氨酸对胚胎海马神经元细胞的影响 总被引:1,自引:1,他引:0
目的 观察同型半胱氨酸(homocysteine,HCY)对海马神经元细胞分化和增殖的作用机理。方法 采用大鼠胚胎海马神经元细胞进行体外培养。观察不同浓度的HCY(0.01、0.1、1.0、10.0、100.0)mmol/L对细胞分化和增殖的影响。结果 随着剂量的增加.同型半胱氨酸对胚胎海马神经元细胞分化和增殖具有抑制作用,并用流式细胞术分析证明对脂质过氧化(LPO)的影响而使得神经元蛋白质含量增高。结论 同型半胱氨酸可抑制胚胎海马神经元细胞分化和增殖的影响,HCY可能在导致神经管畸形的过程起着重要作用。 相似文献
996.
Summary Insulin binding to trophoblast plasma membranes and the placental glycogen content were measured in twelve healthy women, in eleven well-controlled gestational diabetic women who were treated either with diet alone (n=4) or with insulin (n=7) and in 18 women with well-controlled overt diabetes mellitus (six White B; four White C; eight White D). The competitive binding assay was carried out with 22 concentrations of unlabelled insulin. Binding data were analysed by a non-linear direct model fitting procedure assuming one non-cooperative binding site. Maximum specific binding was unchanged in the total collective of gestational diabetic women, but was decreased by 30% in those treated with diet (6.2±2.2%) and increased by 90% in insulin-treated women (16.4±10.2%) as compared to the control subjects (8.7±2.5%). The diet-treated women had only 40% as many and those treated with insulin had more than twice as many receptors compared to control subjects on a per mg protein basis and if expressed per total placenta. In patients with overt diabetes mellitus maximum specific binding (18.5±10.6 %) was higher (p<0.05) due to more receptors compared to control subjects but was similar to the insulin-treated gestational diabetic patients. Maximum specific binding and receptor concentrations did not correlate linearly with maternal plasma insulin levels. Receptor affinities were virtually similar in all groups (1.8·109 l/mol). The placental glycogen content was reduced (p<0.05) to about 80% of that of control subjects in the diet-treated collective, whereas it was unchanged compared to control subjects in the insulin-treated gestational diabetic women despite a 40% increase (p<0.001) of the maternal-to-cord serum glucose ratio. In overt diabetic patients the maternal-to-cord serum glucose ratio and the placental glycogen content were higher (p<0.05) than in the control subjects. We conclude that trophoblast plasma membranes from gestational diabetic women treated with diet alone express less and those from women treated with insulin express more insulin receptors than those from a healthy control group in vitro. These differences could not have been disclosed without consideration of the mode of treatment. Trophoblast plasma membranes from overt diabetic women have more insulin receptors than those from healthy control subjects. 相似文献
997.
998.
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
999.
L. Paczek J. Pazik M. Teschner R. M. Schaefer W. Rowinski J. Szmidt K. Abgarowicz L. Gradowska M. Morzycka-Michalik A. Heidland 《Transplant international》1994,7(S1):311-313
Abstract The major reason for late graft losses is chronic rejection. Recently, a large number of studies have indicated that proteolytic enzymes play an important role as mediators of glomerular injury. The cysteine proteinases cathepsins B and L degrade structural matrix proteins such as type I collagen and laminin. We investigated intraglomerular protease activities in 12 patients after kidney graftectomy because of end-tage renal disease following chronic rejection. A group of 12 patients undergoing nephrectomy because of cancer served as controls using only non-involved parts of the kidney. The activities of cathepsins B and L in homogenates of isolated glomeruli were measured fluorometrically methylcoumarylamidc substrates and related to DNA content. In rejected kidney allografts we observed significantly enhanced intraglomerular cathepsin B activity and cathepsin B + L activity. 相似文献
1000.
Prenatal Stress Increases the Hypothalamo-Pituitary-Adrenal Axis Response in Young and Adult Rats 总被引:11,自引:0,他引:11
Chantal Henry Mohamed Kabbaj Hervé Simon Michel Le Moal Stefania Maccari 《Journal of neuroendocrinology》1994,6(3):341-345
Prenatal stress is considered as an early epigenetic factor able to induce long-lasting alterations in brain structures and functions. It is still unclear whether prenatal stress can induce long-lasting modifications in the hypothalamo-pituitary-adrenal axis. To test this possibility the effects of restraint stress in pregnant rats during the third week of gestation were investigated in the functional properties of the hypothalamo-pituitary-adrenal axis and hippocampal type I and type II corticosteroid receptors in the male offspring at 3, 21 and 90 days of age. Plasma corticosterone was significantly elevated in prenatally-stressed rats at 3 and 21 days after exposure to novelty. At 90 days of age, prenatally-stressed rats showed a longer duration of corticosterone secretion after exposure to novelty. No change was observed for type I and type II receptor densities 3 days after birth, but both receptor subtypes were decreased in the hippocampus of prenatally-stressed offspring at 21 and 90 days of life. These findings suggest that prenatal stress produces long term changes in the hypothalamo-pituitary-adrenal axis in the offspring. 相似文献