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101.
七月盛夏,宝岛台湾却惬意非常!浙江卫视女主播朱丹带领许多媒体朋友一同到南台湾做了一个很特别的美丽之旅,这一次,胶原蛋白不仅可以喝,还能被“看”出来。 相似文献
102.
LC Ewan PJ Charleston SH Pettit 《Annals of the Royal College of Surgeons of England》2014,96(2):e9-e10
Perineal hernia is a rare complication following laparoscopic abdominoperineal resection (APR) for rectal cancer. We present two case reports of perineal hernia following laparoscopic APR and discuss their management. We suggest that they developed because the pelvic peritoneum was left open during laparoscopic APR and propose that closure of the pelvic peritoneum should be routine in this operation. 相似文献
103.
Syngeneic bone marrow transplantation reduces the hearing loss associated with murine mucopolysaccharidosis type VII 总被引:4,自引:0,他引:4
MPS VII mice are deficient in beta-glucuronidase and share many clinical, biochemical, and pathologic characteristics with human mucopolysaccharidosis type VII (MPS VII). We have shown that syngeneic bone marrow transplantation (BMT) prolongs survival and reduces lysosomal storage in many organs of the MPS VII mouse. In this report, we quantify the hearing loss and determine the impact of syngeneic BMT on the development of deafness and the associated pathology in the MPS VII mouse. Eleven weeks after syngeneic BMT performed at birth, treated MPS VII mice had normal auditory-evoked brainstem responses (ABR), whereas untreated MPS VII mice had ABR thresholds 43 dB higher than normal. Treated MPS VII mice had beta-glucuronidase-positive cells in the temporal bone and in the subepithelial connective tissue of the external auditory canal. There was less thickening of the tympanic membrane and middle ear mucosa and decreased distortion of the ossicles and the cochlear bone. Although transplanted MPS VII mice had increased ABR thresholds by 33 weeks of age, four of the six had thresholds 12 to 32 dB lower than untreated mutants. These data indicate that syngeneic BMT in newborn MPS VII mice prevents early hearing loss and, in some animals, results in long-term improved auditory function. 相似文献
104.
Enhanced expression of transforming growth factor beta during megakaryoblastic differentiation of K562 leukemia cells 总被引:5,自引:0,他引:5
Platelet alpha granules contain several growth factors such as the transforming growth factor beta (TGF-beta) that are released during blood clotting and are thought to participate in the repair of tissue injury; however, the site of synthesis of platelet TGF-beta has not been demonstrated. We studied TGF-beta expression during megakaryoblastic differentiation of the chronic myeloid leukemia cell line K562 in vitro. These cells have mainly erythroid characteristics but acquire several megakaryoblastic properties when treated with the phorbol diester 12-0-tetradecanoyl-13-phorbolacetate (TPA). During four subsequent days of megakaryoblastic differentiation the amount of the 2.5-kilobase (kb) TGF-beta mRNA increased about eightfold, and a novel 2.3-kb mRNA species was induced in the K562 cells. This occurred concomitantly with distinct induction patterns of platelet-derived growth factor A (PDGF-A) and c-sis (PDGF-B chain) RNAs and several platelet antigens. The expression of erythroid markers such as glycophorin A decreased. Culture media of TPA-differentiated K562 cells also contained TGF-beta polypeptides as shown by a sensitive radioreceptor assay and by immunoprecipitation after metabolic labeling of the cells. These polypeptides were not seen in culture media from dimethyl sulfoxide- or sodium butyrate-treated cells. Unlike in several other cells, exogenously added TGF-beta 1 or 2 affected neither TGF- beta nor PDGF RNA expression in K562 cells. 相似文献
105.
106.
107.
Maurer AH; Millmond SH; Knight LC; Mesgarzadeh M; Siegel JA; Shuman CR; Adler LP; Greene GS; Malmud LS 《Radiology》1986,161(1):221-225
Indium-111 labeled leukocyte imaging was compared with three-phase skeletal scintigraphy as a means of determining whether osteomyelitis was complicating diabetic osteoarthropathy. Three-phase scintigraphy demonstrated increased activity in both infected and noninfected osteopathic bone, with a sensitivity of 75% and a specificity of 56% for osteomyelitis. Leukocyte imaging had the same sensitivity but was most helpful for excluding infection (specificity, 89%) when three-phase imaging could not. Abnormal leukocyte localization was seen at the primary site of infection in all cases within 4 hours after injection. Disadvantages of leukocyte imaging included long preparation time, low count rates resulting in poor spatial resolution, and absence of bone landmarks, which made it difficult to differentiate soft tissue from bone infection. 相似文献
108.
Summary— Pharmacological and molecular cloning techniques have identified six human subtypes of α-adrenoceptors which are designated α1A, α1B, α1D, α2A, α2B and α2C. At the protein level human kidney expresses predominantly α2A-adrenoceptors while other α2-adrenoceptor subtypes or α1-adrenoceptors have not been detected consistently in radioligand binding studies. However, the presynaptic receptors, which inhibit noradrenaline release in the human kidney, appear to belong to the α2C-subtype. Intrarenal infusion of the nonselective α1-adrenoceptor antagonist, phentolamine, and of the selective α2-adrenoceptor antagonist, yohimbine, but not of the selective α1-adrenoceptor antagonist, doxazosin, increase renal blood flow and renin release in hypertensive patients undergoing diagnostic renal angiography. Thus, α2- but not α1-adrenoceptors appear to mediate a tonic renal vasoconstriction and inhibition of renin release. Effects of systemically given α-adrenoceptor agonists and antagonists are difficult to interpret on a mechanistic level since direct effects in the kidney and indirect effects due to baroreflex activation and peripheral presynaptic and central sympatholytic actions may at least partially offset each other. Moreover, some of these drugs may additionally act independent of α-adrenoceptors, for example, via imidazoline recognition sits. The net result in a given subject may depend on the endogenous sympatho-adrenal tone. Thus, for each target population of interest, effects have to be described empirically for each drug. 相似文献
109.
Defects in human methionine synthase in cblG patients 总被引:6,自引:0,他引:6
Gulati S; Baker P; Li YN; Fowler B; Kruger W; Brody LC; Banerjee R 《Human molecular genetics》1996,5(12):1859-1865
110.
An antifibrin antibody (T2G1s) Fab' fragment labeled with technetium-99m was tested for its ability to produce images of fresh thrombi in dogs. In gamma camera images, all thrombi were evident by 2-4 hours after injection. Mean thrombus-to-blood and thrombus-to-muscle ratios averaged 4.0 and 69 at four hours after injection and increased to 24 and 270, respectively, by 24 hours after injection. When compared with I-125 fibrinogen injected into the same dogs, Tc-99m-antifibrin Fab' had lower absolute uptake in thrombus but higher thrombus-to-blood ratios due to a faster rate of disappearance from the blood. The primary route of excretion was through the kidneys. Tc-99m-antifibrin Fab' was highly stable in vivo, with an average of 82% of the circulating radioactivity able to bind to fibrin at 4 hours after injection. When compared with an In-111-labeled Fab fragment of antifibrin antibody 59D8, thrombus-to-blood and thrombus-to-muscle ratios were slightly higher for the Tc-99m-labeled antibody, and the blood disappearance rate was slightly faster. The absolute uptake in thrombus, however, was not significantly different, and the thrombus was visualized at about the same time after injection. These studies suggest that Tc-99m T2G1s Fab' is a potential agent for detecting thrombi in a clinical setting. 相似文献