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101.
A case of pulmonary Mycobacterium avium (M. avium) disease associated with idiopathic CD4+ T lymphocytopenia is reported. A rapidly growing pulmonary nodule was detected on a chest roentgenogram in a young man. Bronchoscopic examination revealed M. avium infection. Hematological studies showed a low CD4+ cell count in the absence of any identifiable immunodeficiency, including human immunodeficiency virus (HIV) infection. With the combination of chemotherapy and surgery, he had a good clinical outcome. Idiopathic CD4+ T lymphocytopenia should be considered in patients with unexplained opportunistic infection. 相似文献
102.
The zona pellucida (ZP) is an extracellular matrix surrounding the mammalian oocyte. It is involved in the sperm-egg adhesion phenomenon, induces the acrosome reaction, and participates in the late blockage to polyspermy. Thus, during the process of fertilization the cortical reaction is induced and the biochemical and biological properties of the ZP are modified. Some of these changes have been suggested to prevent the polyspermy. However, the mechanisms behind most of these changes are not well understood. Carbohydrate residues of the ZP glycoproteins have been shown to play a key role in the early step of fertilization. In the present study, the changes produced in the terminal oligosaccharide sequences of the rat ZP glycoproteins after in vivo fertilization were investigated by means of lectin-gold cytochemistry. A comparative quantitative analysis of the density of labeling in the ZP before and after fertilization was carried out by automatic counting of gold particles. The ZP of fertilized and unfertilized eggs were labeled by a battery of lectins including PNA, LFA, MAA, AAA, DSA, RCA I, and WGA. For all lectin studied in both fertilized and unfertilized eggs the labeling was preferentially located in the inner region of the ZP. After fertilization, binding of PNA, LFA, MAA, AAA, and DSA decreased in both inner and outer regions of the ZP. Labeling of RCA I-binding sites only decreased in the inner ZP, whereas reactivity to WGA was increased in the inner ZP, whereas reactivity to WGA was increased in the inner area of the ZP. Digestion of the thin-sections with neuraminidase prior to labeling with WGA resulted in a decrease of labeling for WGA binding sites. However, the labeling density of WGA binding sites was similar in both unfertilized and fertilized eggs upon treatment with neuraminidase. The present results demonstrate that the oligosaccharide chains contained in the rat ZP are modified after fertilization of the oocyte. Cortical granules of the oocytes might be involved in these modifications by two mechanisms: 1) by hydrolysis of terminal carbohydrate residues of ZP glycoproteins by specific glycosidases contained in the granules; and 2) by addition of new glycoproteins to the ZP after the exocytosis of the cortical granules (cortical reaction). 相似文献
103.
M Ramírez Fabián MT Vicente Aldea C Ambroj Navarro JM Rodríguez Bazalo A Ucar Terren JG Valdivia Uria 《Canadian Metallurgical Quarterly》1998,22(7):599-601
We present a 3-year-old patient with stenotic kinking of the left internal carotid artery (ICA) who developed an ischaemic infarction of the left brain hemisphere followed by severe neurological sequelae after a prolonged generalized seizure. At time of the seizure the boy was in biological remission of a nephrotic syndrome and received prednisolone and cyclosporin A (CsA) treatment. The haemodynamic consequences of inborn kinking of the ICA is discussed controversely in the literature. The presented case shows that stenotic kinking of the ICA may significantly impair the blood flow towards the homolateral hemisphere and therefore may result in an ischaemic infarction. The influence of CsA on seizure activity is discussed. CONCLUSION: This case provides clinical and radiological evidence supporting an association between stenotic kinking of the carotid artery and homolateral hemispheric brain infarction. 相似文献
104.
Assessment of gallbladder function is required prior to nonsurgical treatment of gallstones. In order to develop a practical and reproducible method of evaluation, gallbladder emptying was studied by ultrasound (US) in 55 gallstone patients after intramuscular administration of ceruletide (0.3 micrograms/kg). In 27 of these subjects, the US procedure was compared to oral cholecystography (OCG) with fatty meal. Maximal percent gallbladder contraction was reached 30 min after ceruletide in all patients. Maximal percent contractions were 47.5 +/- 27.7 during US with ceruletide and 33.9 +/- 16.3 during OCG with fatty meal (p = 0.03). A significant linear relationship was found between the results obtained with the two different procedures (r = 0.57; p = 0.002). Serial US determinations of gallbladder emptying were performed in 16 patients. Individual variation was below 20% in 11 subjects, and in five subjects it ranged between 20 and 40%. Minor, self-limiting side effects were observed in 13 patients. US determination of gallbladder emptying after ceruletide appears to be a practical and reliable method to assess gallbladder function. 相似文献
105.
106.
MA Weinstein MT Modic B Risius PM Duchesneau AJ Berlin 《Canadian Metallurgical Quarterly》1981,138(1):83-87
Altering the scintillation crystal configuration of a fixed-detector CT scanner increased the spatial resolution from 6.25 to 10 line pairs per centimeter. Sector scans of th orbit with this modified scanner showed the ophthalmic artery and superior ophthalmic vein and their branches and the intraorbital branches of the third, fifth, and sixth nerves, apparently seen with CT for the first time. 相似文献
107.
108.
109.
A Bizzi E Veneroni MT Tacconi AM Codegoni R Pagani M Cini S Garattini 《Canadian Metallurgical Quarterly》1980,5(3-4):227-240
Liquipron and Toprina, obtained by growing yeasts (Candida maltosa and Candida lipolytica) on n-hydrocarbons, were investigated to ascertain the biological significance and possible toxicological implications of their high content of uneven fatty acids (UFA). It was confirmed that the extent to which UFA accumulate in adipose tissue of rats fed the 2 products reflects only partially their UFA contents. The presence of UFA in rat tissues does not appear to alter intermediate metabolism. The capacity of liver mitochondria ot oxidize palmitic acid was similar in control and in Liquipron-treated rats. Palmitic acid and heptadecanoic acid did not compete for oxidation when mixed at concentrations which reflect their presence in the tissues of animals fed high levels of Liquipron. 相似文献
110.
The electrical conductivity of pure sodium aluminate solutions with compositions in the range 93 to 128 gl−1 free soda and O to 125 gl−1’ alumina was investigated over the temperature range 40 to 70 °C. Under these conditions, the solution electrical conductivity
was found to vary as a linear function of temperature. For a given free soda content, the temperature coefficient of conductivity
varied as an approximate guadratic function of the alumina content. A single equation was developed relating solution conductivity
to free soda content in the range 105 to 128 gl−1 alumina, 40 to 100 gl−1 over the temperature range 40 to 70 °C. The addition of sodium oxalate and sodium succinate at levels up to 20 gl−1 was found to have no measurable effect on solution conductivity. However, the addition of sodium carbonate at levels of 40
gl−1 had a significant effect, generally decreasing the conductivity. The magnitude of the effect is a complex function of solution
composition and temperature. The technique was used to follow the precipitation of alumina from synthetic Bayer liquor continuously
for 4 h. Possible applications to industrial practice, of the relationship determined, are briefly discussed.
G. R. Browne, formerly Post-Graduate Student, School of Mining and Mineral Technology, Kalgoorlie, Western Australia C. W.
P. Finn, formerly Alcoa Foundation Lecturer in Thermodynamics, School of Mining and Mineral Technology, Kalgoorlie, Western
Australia 相似文献