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101.
人白细胞介素7基因克隆及其真核表达载体的构建 总被引:2,自引:0,他引:2
目的:构建人白细胞介素7(hIL-7)的真核表达载体。方法:从人脾脏组织的总RNA中,用RT-PCR方法扩增出编码成熟hIL-7的cDNA,将其克隆于pMD18-T质粒中,并进行序列测定。再将hIL-7cDNA以正义及反义插入真核、原核双重表达载体pBK-CMV质粒,转化至大肠杆菌DH5α。最后将表达的lacz-hIL-7重组蛋白行SDS-PAGE电泳,并作考马斯亮蓝染色分析,western blot鉴定。结果:hIL-7序列测定结果与预期一致。pBK-CMV-hIL-7(正义插入)的无隆表达重组蛋白,western blot证实此蛋白为IL-7。结论:成功构建了hIL-7的真核表达载体,为进一步研究hIL-7的抗肿瘤作用创造了条件。 相似文献
102.
Four 50 mg and three 100 mg marketed nitrofurantoin tablets were studied in 14 healthy male subjects. Urine was collected 1, 2, 3, 4, 6, 8, 12, and 23 h after each dose, and nitrofurantoin was assayed by HPLC. The in vitro dissolution of the tablets was determined using USP Apparatus 1 and 2, with 0.1 N hydrochloric acid and pH 7.2 buffer as the dissolution fluids. One of the 50 mg tablets was more rapidly and completely absorbed than the other six products. The incidence of side-effects for this product was as low or lower than the other products. It was determined that the use of the USP Apparatus 1, at 100 rev min-1, with sampling of the pH 7.2 fluid at 30 min, provided for the best overall relationship between the urinary excretion and in vitro dissolution. 相似文献
103.
Eleven palatine tonsils were collected from subjects who underwent tonsillectomy in Christian Medical College Hospital and the route of migration of lymphocytes through the high endothelial vessel was studied under EM. In the interendothelial route, migration of a lymphocyte through HEV wall began with the adhesion of a lymphocyte to the surface of endothelial cells by means of a short cytoplasmic projection in the vicinity of intercellular space. The projection extended into the cleft between adjacent endothelial cells. The lymphocyte migrated through HEV by diapedesis. After the lymphocyte had traversed the interendothelial space, it occupied the subendothelial space. In the transendothelial route, migration of a lymphocyte through HEV was initiated by adherence of the lymphocyte to the endothelial cell. The adherent lymphocyte compressed or invaginated into the cytoplasm of the endothelial cell, entered the endothelial cell, was completely enclosed within the endothelial cell cytoplasm, and emerged from the endothelial cell to occupy the subendothelial space. Evidence is presented from static transmission electron microscopic pictures for the migration of lymphocytes by both interendothelial and transendothelial routes through the high endothelial venule. 相似文献
104.
105.
Mary Ellen Turner Kanwal Kher Tamara Rakusan Lawrence D’Angelo Sudesh Kapur Dena Selby Patricio E. Ray 《Pediatric nephrology (Berlin, Germany)》1997,11(2):161-163
We describe the clinical and pathological findings of the hemolytic uremic syndrome (HUS) in two children with human immunodeficiency
virus (HIV) infection. Both patients presented with microangiopathic hemolytic anemia, thrombocytopenia, and subsequently
developed renal failure. The diagnosis of HUS was confirmed by renal histopathology in both patients. None of these children
presented with bloody diarrhea, evidence of circulating antibody response to Escherichia coli O157 lipopolysaccharide, or other known risk factors for HUS, except for the presence of HIV infection. Each patient was
treated with intravenous plasma infusion and renal replacement therapy. Their clinical course was characterized by non-oliguria
and lack of significant hypertension throughout the acute phase of the disease. Despite these favorable clinical parameters,
both patients developed end-stage renal failure. The etiology of this atypical HUS characterized by poor renal survival remains
unknown and the role of HIV infection in its pathogenesis, although possible, is unclear.
Received March 5, 1996; received in revised form and accepted October 15, 1996 相似文献
106.
107.
Brief interruptions of REM sleep are considered to be part of the REM episode. The maximum allowable duration of such an interruption, which is used to define the end of the REM episode, is currently a matter of debate. Making measurements on individual REM cycles, inter-REM interval analysis was carried out to determine whether the generally adopted 15 minute empirical rule for this maximum needs to be extended to 25 minutes as suggested by several including Kobayashi et al. Our results show that there is no reason to alter the 15 minute rule and that measurements which do not take into account the time-of-night effect may be misleading. The proportion of interrupted REM episodes observed in our population of healthy adults is high. We have therefore also examined in some detail the phenomenology of the temporal evolution of the structure and content of the interrupted REM episodes. Both showed a definite change over the night: the interruptions in the earlier episodes tend to return the system to slow wave sleep while those in the later episodes tend to return it to wake. It is hypothesized that these interruptions reflect a measure of REM sleep pressure and its interaction with both slow wave sleep and wake pressures. 相似文献
108.
This paper is based on the book Experiments and Observations on the Gastric Juice and the Physiology of Digestion, originally published in 1833. The book held in the Cowlishaw Collection of the Royal Australasian College of Surgeons is the Edinburgh edition of 1838, which contains a preface by Andrew Combe, MD. The paper explores several aspects of the BeaumontSt Martin story, from St Martin's original injury and the primary care undertaken by Dr William Beaumont, whose numerous studies of the actions and reactions of the stomach were made possible because St Martin was left with a permanent gastric fistula. While the debt we owe to Beaumont is often acknowledged, patients are not mere machines and surgeons must recognize that surgery also owes a debt to its patients; in this case, to Alexis St Martin for what he permitted by way of experiment. 相似文献
109.
Total fluorescence from arterial tissue is influenced by three factors: the absorption coefficient of tissue at a specific
excitation wavelength, the laser excitation power and the fluorescence coefficient which is related to chemical species in
tissue. These various influences were demonstrated by the following experimental results in vitro: (1) the effect of increasing
power on fluorescence intensity, (2) the total fluorescence intensity in normal aorta and plaque and (3) the effect of a chromophore
such as β-carotene on total fluorescence intensity. The fluorescence intensity of normal artery is an incremental function
of laser excitation power, and the fluorescence emission from normal artery compared to fluorescence emission from plaque
is significantly different at the same excitation power. The total fluorescence of normal artery was measured to be twice
as great as that of atheromatous plaque (relative mean ratio of 2.58±0.46 compared to unity,p<0.0002 at 488 nm; relative mean ratio of 2.57±0.51 compared to unity,p<0.0009 at 514 nm). The total fluorescence emission decreases with the increase of β-carotene content in arterial tissue (R=0.97). These emission differences, when intensified by an exogenous chromophore of β-carotene, may provide an improved guidance
signal for diagnosis of plaque from normal artery during laser angioplasty procedures. 相似文献
110.
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