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11.
基于非标准协议的短距离无线通信,具有成本低、易开发、低功耗的优点,非常适用于小范围内的数据传输。提出一种基于非标准无线通信芯片nRF24L01的个人健康监护系统设计方案,并将其与现有的、基于标准协议无线通信的个人健康监护系统进行比较。结果表明:基于非标准协议无线通信的个人健康监护系统具有效率高、功耗低、通信性能好的特点。 相似文献
12.
Impact of Ingested Liquids on 24-Hour Ambulatory pH Tests 总被引:1,自引:0,他引:1
J. Patrick Shoenut Donald Duerksen Clifford S. Yaffe 《Digestive diseases and sciences》1998,43(4):834-839
A prospective investigation of the impact ofingested liquids on 24-hr pH test scores was conducted.Eighty-two patients contributed 142 samples. The liquidsused were coffee/tea (N = 35), water (N = 32), fruit juice (N = 29), cola (N = 34), and beer (N =12). The pH of cola, juice, and beer are approximately3.0. The parameters studied included: total test time,total drink time, total minutes of pH < 4.0 during drink, minutes of pH < 4.0 10 min beforedrink, and minutes of pH < 4.0 10 min followingdrink. Analysis was performed using one-way ANOVA andrepeated measures. Age of patients, total test time, and total time pH < 4.0 were notsignificantly different (P > 0.05). The total time toconsume the drink was significantly greater (P <0.05) for beer than all other liquids. The total time(7.7 ± 6.0 min) pH < 4.0 for cola wassignificantly different (P < 0.023) than beer (3.3± 3.7 min), tea/coffee (1.4 ± 6.5 min),and water (1.1 ± 2.5 min). The percentage oftotal time pH < 4.0 was not significantly different (P >0.05) among any of the liquids. The percentage of timepH < 4.0 during the drink was the highest for cola(63 ± 47%) and juice (51 ± 57%); water,coffee/tea, and beer were not significantly different (P> 0.05). Although the impact of cola and juice werethe greatest, none of these had an impact that exceeded0.5%. The lack of impact of beer appears to be due to the increased period of time it takes toconsume. We conclude that the impact of ingested fluidsis minimal and can probably be disregarded in mostpatient groups. 相似文献
13.
Anita Sydbom 《Naunyn-Schmiedeberg's archives of pharmacology》1988,338(5):567-572
Summary Rat peritoneal mast cells were exposed to the neurohormone and basic opioid peptide -endorphin. -Endorphin induced a dose-dependent release of histamine from the mast cells. A significant histamine release was found at 5 mol/l of -endorphin and maximal release (35% of total) at 20 mol/l. The histamine release process was very rapid and terminated within 30 s at 37°C, and in this sense is very similar to the histamine release induced by compound 48/80 or neurotensin. The histamine release was temperature-dependent showing an optimum release around 30°C, and it was independent of available extracellular calcium, but was inhibited in the presence of high extracellular calcium concentrations. Naloxone, only in very high concentrations (10 mmol/l), inhibited the release, and the very same concentration also inhibited the neurotensin — as well as the compound 48/80-induced histamine release. Cromoglycate and benzalkoniumchloride, a 48/80 antagonist, both produced a progressive dose-dependent inhibition of -endorphin-, neurotensin- as well as compound 48/80-induced histamine release. Taken together, the findings indicate that the opioid peptide -endorphin induces a selective, energy-dependent release of histamine from peritoneal rat mast cells. The pattern of release has much in common with that of compound 48/80 and other basic peptides, such as neurotensin and substance P. In addition this pattern of release is similar to that induced by dynorphin.
Send offprint requests to Anita Sydbom at the above address 相似文献
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Malamachanahalli B. Vasudevachari Norman P. Salzman Daniel R. Woll Christopher Mast Katharina W. Uffelman Gary Toedter David Hoefheinz Julie A. Metcalf H. Clifford Lane 《Journal of clinical immunology》1993,13(3):185-192
The presence of p24 core antigen in the serum of individuals with human acquired immunodeficiency syndrome has been used as one of the important prognostic markers of HIV-1 infection and also as an end point in evaluating antiviral drugs and vaccines. Unfortunately the majority of p24 antigen present in serum exists as an antigenantibody complex and is not detected with the commercial kits currently available to measure p24 antigen. In this study, we report a simple procedure utilizing treatment of serum samples with glycine buffer (pH 1.85) to dissociate antigen-antibody complexes prior to assaying for p24 antigen. A 300% increase in the number of p24-reactive samples and a 3- to 12-fold increase in the quantity of antigen detected were observed when samples were pretreated with 1.5M glycine buffer (pH 1.85) for 1 hr. Glycine treatment of samples did not result in nonspecific positive tests and samples previously shown to be reactive remained positive. In reconstruction experiments the release of antigen was found to be inversely proportional to the amount of p24 antibody present in the serum. The percentage of HIV-1-infected patients positive for p24 antigen was clearly a function of CD4 count. Forty-nine percent of patients with more than 500 CD4 cells and 100% of patients with less than 200 CD4 were p24 positive. The improved sensitivity for detection of p24 provided by this procedure enhances our understanding of the pathogenesis of AIDS by showing that the majority of patients with HIV-1 infection is p24 positive and facilitates the analysis of data obtained in clinical trials involving anti-HIV compounds. 相似文献
17.
Aidan P. McManus Barry A. Gusterson C. Ross Pinkerton Janet M. Shipley 《The Journal of pathology》1995,176(2):137-142
It is increasingly recognized that the identification of t(11;22)(q24;q12) is a useful aid in the accurate diagnosis of Ewing's sarcoma and related tumours. However, cytogenetic studies have a low success rate and adequate tumour is not always available. This study describes the use of fluorescence in situ hybridization (FISH) to detect translocations at 22q12, the site of the EWS gene involved in t(11;22)(q24;q12), on tumour touch imprints made from true cut core-needle biopsy and frozen tumour. Of the seven tumours analysed, five diagnosed as Ewing's sarcoma or primitive neuroectodermal tumour demonstrated chromosome translocation at 22q12. This is a rapid and reliable method to detect a diagnostically relevant chromosome translocation using minimal amounts of fresh or frozen tumour. 相似文献
18.
Objective To study the distribution and quantity of CD44VCD24- cells in breast cancer tissue and the cell lines,and as well as its correlation with the expression of various breast cancer markers and molecular subtyping of breast carcinoma.Methods The expression of CD44 / CD24,estrogen receptor,progesterone receptor,HER2,human estrogen-induced protein PS2,bcl-2 and nm23 in 60 cases of invasive ductal carcinoma of breast were studied by either single or double immunohistochemical staining.The co-expression of CD44 and CD24 in 3 breast cancer cell lines (MCF-7,MDA-MB-468,and MDA-MB- 231) was also examined.Results The quantity and distribution of CD44 + /CD24- cells varied greatly and no specific patterns were identified.The percentage of CD44 + /CD24- in breast cancer was 65%.The amount of CD44+/CD24- cells did not correlate with the age of patients,lymph node metastasis,tumor size,molecular subtypes and expression of various breast cancer markers in breast carcinoma.The proportion of CD44+/CD24- cells in MCF-7,MDA-MB-468,and MDA-MB-231 cell lines was < 1%,5% and > 80% ,respectively.Conclusions CD44+ /CD24- cells are demonstrated in certain breast cancer tissues and cell lines.However,there is no relationship obtained between the quantity or the distribution of these cells and the molecular subtyping or the clinicopathologic parameters in breast cancer. 相似文献
19.
目的: 研究胃良恶性病变组织中癌干细胞标记物CD24、CD44v6的表达并探讨其临床病理意义。方法: 49例胃癌、20例癌旁组织、36例淋巴结转移灶及80例不同类型胃良性病例(浅表性胃炎10例,萎缩性胃炎15例,胃溃疡20例,胃息肉20例,胃腺瘤15例)标本常规制作石蜡包埋切片,CD24和CD44v6染色方法为EnVision免疫组化法。结果: 胃癌病例CD24和CD44v6表达阳性率明显高于癌旁组织和不同类型胃良性病变(P<0.05或P<0.01),且阳性表达的良性病例胃黏膜上皮均呈中至重度不典型增生;转移灶CD24和CD44v6表达与相应原发灶呈现高度一致性(P>0.05);组织学分级Ⅱ级、无淋巴结转移及无远处器官转移胃癌病例CD24和CD44v6表达阳性率明显低于组织学分级Ⅲ或Ⅳ级、淋巴结转移及远处器官转移病例(P<0.05)。此外,浸润深度T1-T2及淋巴结N1站转移病例CD24表达阳性率明显低于浸润深度T3-T4和淋巴结N2、N3站转移病例(P<0.05)。结论: CD24和CD44v6表达可能是反映胃癌发生、进展、生物学行为和预后的重要癌干细胞标记物,检测胃良性病例CD24和CD44v6表达水平对预防和早期发现胃癌可能有一定的临床价值。 相似文献
20.
Angiotensin peptides and inducible transcription factors 总被引:8,自引:0,他引:8