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991.
Z Abbas I Moid AH Khan SM Jafri SH Shah S Abid S Hamid 《Canadian Metallurgical Quarterly》1996,90(5):507-513
The ultrastructure of autonomic nerve fibers and terminal varicosities is described in relation to the lamina propria of the human seminiferous tubules during childhood (age 3 to 10 years). Autonomic nerve varicosities are classified as: Type I with numerous small (30-60 nm) agranular vesicles and variable numbers of large (100 nm) granular vesicles, and Type II with numerous small (30-60 nm) granular vesicles and sporadic large granular vesicles. These two varicosity types are consistent in morphology with cholinergic and adrenergic nerve terminals, respectively. Nerve varicosities are found, associated with Schwann cells, in proximity to the cells of the lamina propria. Although not found in direct "synaptic' contact, these autonomic endings are often within a few hundred nanometers of the cellularity of the lamina propria. The Schwannian sheath is interrupted over the varicosities at these sites and occasionally the terminal varicosities are totally lacking a Schwann sheath. These findings are consistent with the structural relationship of autonomic nerve "terminals' and effector in other endocrine and non-endocrine systems. This is the first evidence of adrenergic nerve varicosities in proximity to the lamina propria in humans (at any age). Evidence is also presented which suggests a locational difference in the distribution of cholinergic (Type I) and adrenergic (Type II) nerve varicosities in this region, with only cholinergic endings observed directly adjacent to the basal lamina of the seminiferous tubules. 相似文献
992.
Unicompartmental knee arthroplasty is an appropriate method of treating selected patients with osteoarthritis of the medial compartment of the knee. The common causes of failure are aseptic loosening, infection, patellofemoral pain, and deterioration in the opposite compartment. Seven cases of a cohort of 32 Robert Brigham unicondylar knee replacements that failed because of early catastrophic wear of the polyethylene tibial component are reported. Possible reasons suggested for failure include inadequate thickness of polyethylene, fusion defects in the polyethylene structure as a result of the sterilization process, increased rotational freedom, and reduced conformity in the design of the prosthesis. 相似文献
993.
2'-Azido-2'-deoxyuridine and 2'-azido-2'-deoxycytidine were evaluated for their inhibitory activity against ribonucleotide reductase and for subsequent cell growth inhibition. Their mono- and di-phosphates were synthesized and their inhibitory activities against the reductase were also determined in a permeabilized cell system, along with the two nucleosides. The results of the present study identify the first phosphorylation step involved in the conversion of the two azidonucleosides to the corresponding diphosphates to be rate-limiting in the overall activation. 相似文献
994.
995.
The volatile composition and properties of wine made using the ‘Cheongsoo’ grape cultivar harvested at different stages of ripening were evaluated. There were changes in the chemical composition of ‘Cheongsoo’ wine, including pH, total acidity, total polyphenols, and tannins according to the degree of grape ripening. Colorimetric analysis indicated that wines had yellow tones and deep and very strong colors with a high chromatic intensity depending on the degree of grape ripening. Of 87 detected flavor compounds, 26 had high OAV (odor active values). Based on OAV, 26 compounds were considered to be important odorants for ‘Cheongsoo’ wine. A harvest date of September 19 showed good separation from August 29 and September 8 and 29, depending on the degree of grape ripening, on a principle components analysis plot for grape ripening. More volatile compounds were present in September 19 harvested grapes. 相似文献
996.
Christopher S. Choi Jonathan Lau Janet Hur Leland Smith Chunlei Wang Bruce Dunn 《Advanced materials (Deerfield Beach, Fla.)》2018,30(1)
One of the important considerations for the development of on‐chip batteries is the need to photopattern the solid electrolyte directly on electrodes. Herein, the photopatterning of a lithium‐ion conducting solid electrolyte is demonstrated by modifying a well‐known negative photoresist, SU‐8, with LiClO4. The resulting material exhibits a room temperature ionic conductivity of 52 µS cm?1 with a wide electrochemical window (>5 V). Half‐cell galvanostatic testing of 3 µm thin films spin‐coated on amorphous silicon validates its use for on‐chip energy‐storage applications. The modified SU‐8 possesses excellent mechanical integrity, is thermally stable up to 250 °C, and can be photopatterned with micrometer‐scale resolution. These results present a promising direction for the integration of electrochemical energy storage in microelectronics. 相似文献
997.
Seungwon Yoon Yunhui Min Chungyu Park Dahye Kim Yunji Heo Mangeun Kim Eugene Son Mrinmoy Ghosh Young-Ok Son Chang-Gi Hur 《International journal of molecular sciences》2022,23(18)
Although allogenic meniscus grafting can be immunologically safe, it causes immune rejection due to an imbalanced tissue supply between donor and recipient. Pigs are anatomically and physiologically similar to adult humans and are, therefore, considered to be advantageous xenotransplantation models. However, immune rejection caused by genetic difference damages the donor tissue and can sometimes cause sudden death. Immune rejection is caused by genes; porcine GGTA1, CMAH, and B4GLANT2 are the most common. In this study, we evaluated immune cells infiltrating the pig meniscus transplanted subcutaneously into BALB/c mice bred for three weeks. We compared the biocompatibility of normal Jeju native black pig (JNP) meniscus with that of triple knockout (TKO) JNP meniscus (α-gal epitope, N-glycolylneuraminic acid (Neu5Gc), and Sd (a) epitope knockout using CRISPR-Cas 9). Mast cells, eosinophils, neutrophils, and macrophages were found to have infiltrated the transplant boundary in the sham (without transplantation), normal (normal JNP), and test (TKO JNP) samples after immunohistochemical analysis. When compared to normal and sham groups, TKO was lower. Cytokine levels did not differ significantly between normal and test groups. Because chronic rejection can occur after meniscus transplantation associated with immune cell infiltration, we propose studies with multiple genetic editing to prevent immune rejection. 相似文献
998.
Flexible Inorganic Piezoelectric Acoustic Nanosensors for Biomimetic Artificial Hair Cells
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Hyun Soo Lee Juyong Chung Geon‐Tae Hwang Chang Kyu Jeong Youngdo Jung Jun‐Hyuk Kwak Hanmi Kang Myunghwan Byun Wan Doo Kim Shin Hur Seung‐Ha Oh Keon Jae Lee 《Advanced functional materials》2014,24(44):6914-6921
For patients who suffer from sensorineural hearing loss by damaged or loss of hair cells in the cochlea, biomimetic artificial cochleas to remedy the disadvantages of existing implant systems have been intensively studied. Here, a new concept of an inorganic‐based piezoelectric acoustic nanosensor (iPANS) for the purpose of a biomimetic artificial hair cell to mimic the functions of the original human hair cells is introduced. A trapezoidal silicone‐based membrane (SM) mimics the function of the natural basilar membrane for frequency selectivity, and a flexible iPANS is fabricated on the SM utilizing a laser lift‐off technology to overcome the brittle characteristics of inorganic piezoelectric materials. The vibration amplitude vs piezoelectric sensing signals are theoretically examined based on the experimental conditions by finite element analysis. The SM is successful at separating the audible frequency range of incoming sound, vibrating distinctively according to varying locations of different sound frequencies, thus allowing iPANS to convert tiny vibration displacement of ≈15 nm into an electrical sensing output of ≈55 μV, which is close to the simulation results presented. This conceptual iPANS of flexible inorganic piezoelectric materials sheds light on the new fields of nature‐inspired biomimetic systems using inherently high piezoelectric charge constants. 相似文献
999.
Influence of yeast strains on the physicochemical characteristics,methanol and acetaldehyde profiles and volatile compounds for Korean rice distilled spirit
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Han Sub Kwak Jae Soon Seo Yesung Hur Hyoung‐Seok Shim Yougnseung Lee Misook Kim Yoonhwa Jeong 《Journal of the Institute of Brewing》2015,121(4):574-580
The objective of this study was to investigate the influence of yeast strains on the physicochemical characteristics, methanol and acetaldehyde profiles, and volatile compounds of Korean rice distilled spirits. Ten yeast strains were employed for the brewing of distilled spirits and the resulting products were filtered and distilled twice. The amounts of methanol and acetaldehyde for the ten yeasts showed different profiles. Higher amounts of methanol were detected for strains CL, CY, DV, BD, ED and LP, while EC, D2, D4 and RH had <2 mg L?1 methanol content. Strains D2, BD and ED produced the lowest amounts of acetaldehyde. The head portions of the spirits, which started in the fraction that contained <5 mg L?1 of acetaldehyde, were between 7.7% (BD) and 18.2% (LP) of the total fractions. Strains D2, CL and CY produced more alcohol in the body fraction than the other yeasts. The major volatile compounds were esters in the form of fatty acid ethyl esters, such as ethyl palmitate, ethyl myristate and ethyl oleate. Isoamyl alcohol, which is an important volatile compound for rice wine, occupied 0.91–2.24% of the relative peak areas. Strain D2, of the strains tested, appeared to be the most appropriate yeast for Korean distilled spirit based on alcohol production and the high relative peak area of volatile compounds, except for ethanol. Strains CL and CY could also be considered for producing high‐quality Korean rice distilled spirits with efficiency and flavour. Copyright © 2015 The Institute of Brewing & Distilling 相似文献
1000.
GL Harton P Tsipouras ME Sisson KM Starr BS Mahoney EF Fugger JD Schulman MW Kilpatrick G Levinson SH Black 《Canadian Metallurgical Quarterly》1996,2(9):713-715
Marfan syndrome (MFS) is an autosomal dominant disease that affects the skeletal, ocular and cardiovascular systems. Defects in the gene that codes for fibrillin (FBN-1) are responsible for MFS. Here we report the world's first use of preimplantation genetic testing (PGT) to achieve a clinical pregnancy and live birth of a baby free of a Marfan mutation. One or two blastomeres from each embryo were tested for a CA repeat within the FBN-1 gene. The prospective mother is homozygous for the CA repeat (2/2) and has two normal copies of the FBN-1 gene, while the prospective father is heterozygous for the CA repeat (1/2), and is affected with the Marfan syndrome. In the father's family, allele 2 segregates with the mutated FBN-1 gene. For PGT, any embryo diagnosed as heterozygous for the CA repeat (1/2) would be presumed to have inherited normal FBN-1 genes from the father and the mother and be unaffected. One in-vitro fertilization (IVF) cycle yielded 12 embryos for preimplantation testing; six of the embryos were heterozygous for the CA repeat (1/2) and presumed to be free of the Marfan mutation. Five of the six embryos were subsequently transferred into the uterus. The fetus was tested by chorionic villus sampling and found to be free of the Marfan mutation by the same linkage analysis, had a normal fetal echocardiogram, and was normal at birth. 相似文献