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51.
We investigated nonisothermal (fast) and nominally isothermal hydrothermal liquefaction (HTL) of Nannochloropsis sp. microalgae for the production of biocrude. Biocrude yields ranged from 36 to 45 wt % (dry weight), with fast HTL with low mass loading giving the highest yield. This condition also gave the biocrude with the lowest heating value, which indicates there are compromises to be made between biocrude quantity and quality. The aqueous phase and biocrude product fractions were characterized using elemental analysis and Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR MS). This detailed level of analysis identified more than 30,000 unique molecular products. The aqueous phase products included compounds with the same molecular formulae as known herbicides, which may inform efforts in genetic engineering of algae and/or bacteria for cultivation on the aqueous phase. This detailed molecular‐level characterization provides some clues regarding the types of reactions that may take place during HTL. © 2016 American Institute of Chemical Engineers AIChE J, 62: 815–828, 2016  相似文献   
52.
Near-infrared (NIR) time-resolved and spectroscopic transillumination imaging techniques are used to investigate normal tissues and Warthin's tumor of human parotid glands. The time-sliced imaging arrangement uses 120-fs, 1-kHz repetition-rate, 800-nm pulses from a Ti: sapphire laser and amplifier system for sample illumination and an ultrafast gated intensified camera system (UGICS) for recording two-dimensional (2-D) images using transmitted light. Images recorded with earlier temporal slices (approximately first 100 ps) of transmitted light highlight the tumor, while those recorded with later temporal slices (later than 200 ps) accentuate normal tissues. The spectroscopic imaging arrangement uses 1210-1300 nm tunable output of a Cr: forsterite laser for sample illumination, a Fourier space gate to discriminate against multiple-scattered light, and a NIR area camera to record 2-D images. The tumor region in the specimen appears brighter than the normal region in spectroscopic images recorded with light of different wavelengths. A wavelength-dependent variation in the ratio of light transmission through the tumor to that through the normal parotid gland is observed. Differences in scattering and wavelength-dependent absorption characteristics of normal parotid gland and Warthin's tumor provide a consistent explanation of these observed features. Histopathological analysis of the specimen sheds light on the probable origin of the differences in scattering and absorption characteristics  相似文献   
53.
54.
The South Pole Imaging Fabry-Perot Interferometer (SPIFI) is the first instrument of its kind-a direct-detection imaging spectrometer for astronomy in the submillimeter band. SPIFI's focal plane is a square array of 25 silicon bolometers cooled to 60 mK; the spectrometer consists of two cryogenic scanning Fabry-Perot interferometers in series with a 60-mK bandpass filter. The instrument operates in the short submillimeter windows (350 and 450 microm) available from the ground, with spectral resolving power selectable between 500 and 10,000. At present, SPIFI's sensitivity is within a factor of 1.5-3 of the photon background limit, comparable with the best heterodyne spectrometers. The instrument's large bandwidth and mapping capability provide substantial advantages for specific astrophysical projects, including deep extragalactic observations. We present the motivation for and design of SPIFI and its operational characteristics on the telescope.  相似文献   
55.
The prognosis in patients with primary brain tumors treated with surgery, radiotherapy and conventional chemotherapy remains poor. To improve outcome, combination high-dose chemotherapy (HDC) has been explored in children, but rarely in adults. This study was performed to determine the tolerability of three-drug combination high-dose thiotepa (T) and etoposide (E)-based regimens in pediatric and adult patients with high-risk or recurrent primary brain tumors. Thirty-one patients (13 children and 18 adults) with brain tumors were treated with high-dose chemotherapy: 19 with BCNU (B) and TE (BTE regimen), and 12 with carboplatin (C) and TE (CTE regimen). Patients received growth factors and hematopoietic support with marrow (n = 15), peripheral blood progenitor cells (PBPC) (n = 11) or both (n = 5). The 100 day toxic mortality rate was 3% (1/31). Grade III/IV toxicities included mucositis (58%), hepatitis (39%) and diarrhea (42%). Five patients had seizures and two had transient encephalopathy (23%). All patients had neutropenic fever and all pediatric patients required hyperalimentation. Median time to engraftment with absolute neutrophil count (ANC) >0.5 x 10(9)/l was 11 days (range 8-37 days). Time to ANC engraftment was significantly longer (P = 0.0001) in patients receiving marrow (median 14 days, range 10-37) than for PBPC (median 9.5 days, range 8-10). Platelet engraftment >50 x 10(9)/l was 24 days (range 14-53 days) in children. In adults, platelet engraftment >20 x 10(9)/l was 12 days (range 9-65 days). In 11 patients supported with PBPC, there was a significant inverse correlation between CD34+ dose and days to ANC (rho = -0.87, P = 0.009) and platelet engraftment (rho = -0.85, P = 0.005), with CD34+ dose predicting time to engraftment following HDC. Overall, 30% of evaluable patients (7/24) had a complete response (CR) (n = 3) or partial response (PR) (n = 4). Median time to tumor progression (TTP) was 7 months, with an overall median survival of 12 months. These TE-based BCNU or carboplatin three-drug combination HDC regimens are safe and tolerable with promising response rates in both children and older adults.  相似文献   
56.
The localization of cathepsin K protein in mouse osteoclasts was examined by immunolight and immunoelectron microscopy using the avidin-biotin-peroxidase complex method with anti-cathepsin K (mouse) antibody. With light microscopy, a strong immunoreaction for cathepsin K was found extracellularly along the bone and cartilage resorption lacunae and detected intracellularly in vesicles, granules, and vacuoles throughout the cytoplasm of multinuclear osteoclasts and chondroclasts attached to the surface of the bone or cartilage. Mononuclear cells, probably preosteoclasts, some distance from the bone also contained a few cathepsin K-positive vesicles and granules. Cathepsin K was sometimes found in the cisternal spaces of the rough endoplasmic reticulum and vesicles of the Golgi apparatus with electron microscopy of the basolateral region of the osteoclasts. Cathepsin K-positive vesicles and granules as lysosomal compartments were present in various stages of fusion with vacuoles as endosomal compartments that contained fragmented cathepsin K-negative fibril-like structures. Some of the vacuoles (endolysosomes), which seemed to be formed by this process of fusion, contained cathepsin K-positive vesicles and fibril-like structures that did not show the regular cross striation of type I collagen fibrils. In the apical region of the osteoclasts, cathepsin K-positive vesicles and pits had already fused with or were in the process of fusing with the ampullar extracellular spaces. There were large deposits of cathepsin K on fragmented fibril-like structures without regular cross striation in the extracellular spaces, as well as on and between the cytoplasmic processes of the ruffled border. There were also extensive deposits of cathepsin K on the type I collagen fibrils with cross striation in the bone resorption lacunae. Osteoblasts and osteocytes were negative for cathepsin K. In the immunocytochemical controls, no immunoreaction was found in the osteoclasts or preosteoclasts, or on the collagen fibrils in the resorption lacunae. The results indicate that cathepsin K is produced in mature osteoclasts attached to the bone and secreted into the bone resorption lacunae. The findings suggest that cathepsin K participates in the extracellular degradation of collagen fibrils in the resorption lacunae and in the subsequent degradation of the fragmented fibrils in the endolysosomes. It is also suggested that cathepsin K degrades the organic cartilage matrix.  相似文献   
57.
Using polymerase chain reaction (PCR) a complementary DNA (cDNA) encoding a 5-hydroxytryptamine (5-HT) receptor was isolated from rat forebrain. The amplified cDNA specifies an open reading frame of 374 amino acids comprising seven putative transmembrane regions. Expression of the cloned cDNA in human embryonic kidney cells (HEK 293) was used to establish the pharmacological profile of the encoded receptor polypeptide. Membranes containing the cloned receptor showed high affinity binding of [3H]-5-HT. Competition binding experiments with a variety of serotonin receptor ligands displayed a rank order of affinities corresponding to a 5-HT1D subtype: 5-CT > 5-HT = metergoline > CGS 12066 > methysergide > sumatriptan > mianserin = (-)alpha-Me-5-HT = yohimbine > 8-OH-DPAT > or = rauwolscine > spiperone > DOI > propranolol > or = 2-Me-5-HT > or = ICS 205930. Ketanserin and ritanserin displaced [3H]-5-HT-binding in a biphasic manner. In situ hybridization revealed highest expression of the corresponding mRNA in the pyramidal layer of the olfactory tubercle and the nucleus caudatus and accumbens.  相似文献   
58.
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) expression is increased in Dunning R-3327 rat prostatic adenocarcinoma cell lines relative to normal rat ventral prostate tissue. GAPDH expression closely correlates with cell motility of Dunning prostate cancer cell lines and accurately distinguishes cell lines with high metastatic potential from those with low metastatic potential. Increased GAPDH expression in the cancer cell lines is not simply related to increased growth rate, since rapidly proliferating normal prostate tissue did not exhibit elevated GAPDH expression.  相似文献   
59.
Colostrinin: a proline-rich polypeptide (PRP) from ovine colostrum and its nonapeptide active fragment (NP) induce maturation and differentiation of murine thymocytes, formation of helper cells from PNAhigh thymocytes and cytotoxic T cells from PNAlow thymocytes. These processes are accompanied by changes in expression of receptors for peanut agglutinin (PNA), PNAhigh thymocytes were transformed into PNAlow cells, and vice versa. It was shown, in various laboratories, that sialyltransferases are involved in the transformation of PNAhigh thymocytes into PNAlow cells. To find out whether the expression of receptors for PNA on murine thymocytes might also be influenced by other enzymes, we decided to study the effect of PRP and NP on sialidase and beta-galactosidase activities in these cells. The results obtained showed that the most of sialidase activity of murine thymocytes is present in the plasma membrane compartments. Both thymocyte subpopulations PNAhigh and PNAlow, showed similar sialidase activity, which was not affected either by PRP or NP. In contrast to sialidases, most of beta-galactosidase activity was present in the cytosol. PNAhigh, thymocytes showed a higher beta-galactosidase activity than PNAlow cells. Incubation of immature, PNAhigh, thymocytes with PRP or NP enhanced the beta-galactosidase activity in these cells. The presented results suggest that sialidases seem not to be involved in modulation of surface sialic acid content during murine thymocyte maturation. On the other hand, stimulation of activity of beta-galactosidase in PNAhigh, immature thymocytes by PRP and NP suggests that beta-galactosidase in murine thymocytes might be involved in transformation of PNAhigh into PNAlow cells.  相似文献   
60.
Pustulosis palmoplantaris (PPP) is a common chronic skin disease, which is very resistant to treatment. It is not known why the lesions are located in the palms and soles. There are few studies of the disease and in particular studies of the histology. Fifty-nine patients with PPP answered a questionnaire concerning their medical history and 39 of them were clinically examined. Biopsy specimens were taken from involved skin in 22 of the 39 patients and studied immunohistologically for tryptase+ mast cells, EG2+ eosinophils, lipocalin+ neutrophils and CD3+ T lymphocytes. The sweat gland and sweat duct were visualized with AE1/AE3 antibody (cytokeratins 1-8, 10, 14/15, 16, 19). In addition to neutrophils in the pustule and lymphocytes in the upper dermis, there were also large numbers of mast cells and eosinophils in the subpustular area. Numerous eosinophils were present in the pustule. The epidermal part of the eccrine duct was not detectable in any of the specimens from patients with PPP but was present in all of the nine control persons (including two smokers). The results indicate that the acrosyringium is involved in the inflammation and also that mast cells and eosinophils participate in a hitherto unknown way. Of the 39 patients clinically examined, two had previously diagnosed thyroid disease and two had gluten hypersensitivity. Seventeen had one or several abnormal serum concentrations of thyroid-stimulating hormone, thyroxin, antibodies against thyroglobulin or thyroperoxidase and 10 had immunoglobulin (Ig) A antibodies to gliadin. The mean +/- SD for serum IgA and for eosinophil cationic protein was increased. From the questionnaire the most notable finding was that 56 of the 59 patients had been or still were smokers, all of whom had started smoking before the first signs of PPP. We hypothesize that the acrosyringium might be the target for the inflammation and that PPP is linked to autoimmune thyroid disease and smoking.  相似文献   
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