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131.
132.
从榆耳(Gloeostereum incarnatum S.Ito et Imai)的液体发酵物中经层析分离得一新倍半萜榆耳三醇(gloeosteretriol),根据红外光谱、核磁共振谱和质谱数据推定其结构为Ⅰ,并用X-射线晶体衍射进一步确证其结构和立体构型。  相似文献   
133.
Percutaneous insertion of a radiopaque marker is an important technique used in radiotherapy planning for both external-beam and brachytherapy. It is of particular importance in the oral cavity. We describe the construction and use of a simple inserter for‘cold’gold seeds manufactured from a commercially available Becton Dickinson Brand 5-mL disposable syringe and a Becton Dickinson Brand 18 G 1/2 TW (1.25 × 38 mm) hypodermic needle.  相似文献   
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Griffin  JD; Young  D; Herrmann  F; Wiper  D; Wagner  K; Sabbath  KD 《Blood》1986,67(5):1448-1453
Proliferation of acute myeloblastic leukemia (AML) cells in vitro is limited in most cases to a small subset of blasts that have several properties of stem cells. These leukemic colony-forming cells (AML-CFU) generally require addition of exogenous growth factors for proliferation in agar or methylcellulose. These factors can be supplied by media conditioned by phytohemagglutinin-stimulated normal leukocytes or by CSF-secreting tumor cell lines. However, the exact factor or factors required for stimulation of AML-CFU growth have not been defined. We compared the AML-CFU stimulatory activity of a human recombinant GM-CSF with that of GCT-CM, Mo-CM, and the PHA-leukocyte feeder system in 15 cases of AML. In each of the 12 cases that required exogenous growth factors for maximum AML-CFU growth, recombinant GM-CSF could replace either GM-CSF or Mo-CM, and could partially replace the PHA-leukocyte feeder system. These results indicate that this GM-CSF is a growth promoter of AML-CFU in these culture systems.  相似文献   
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In this issue MacMillan and McCarron in 2010 demonstrated that the phospholipase C (PLC) inhibitor U-73122 can potently inhibit Ca2+ release from isolated smooth muscle cells independent of its effect on PLC. Their data suggest that the PLC inhibitor can block the sarcoplasmic/endoplasmic reticulum calcium ATPase pump in smooth muscle and cast doubt on the reliability of U-73122 as the main pharmacological tool to assess the role of the phosphotidyl inositol-PLC pathway in cellular signalling.  相似文献   
139.
Magnetic resonance arteriograms of healthy volunteers and selected patients were produced with a new spoiled gradient-echo pulse sequence based on time-of-flight phenomena. The procedure involves sequential acquisition of many contiguous, thin (1.5-mm) axial two-dimensional sections. These volume data are then submitted to a raytracing projection program, which retrospectively yields multiple arbitrary projection angles rotating through any plane. Venous structures are suppressed with a presaturation slab superior to the current section. The slab location is advanced in concert with advancement of each new section location. The acquisition time varies from 6 to 13 minutes, depending on the number of sections acquired for three-dimensional display. This method obviates the subtraction of image data sets to suppress signals from stationary spins, is more sensitive to slow blood flow than three-dimensional methods of acquisition, and shows special promise for the study of extracranial vascular disease.  相似文献   
140.
Bergman JEH, Blake KD, Bakker MK, du Marchie Sarvaas GJ, Free RH, van Ravenswaaij‐Arts CMA. Death in CHARGE syndrome after the neonatal period. CHARGE syndrome is a multiple congenital anomaly syndrome that can be life‐threatening in the neonatal period. Complex heart defects, bilateral choanal atresia, esophageal atresia, severe T‐cell deficiency, and brain anomalies can cause neonatal death. As little is known about the causes of death in childhood and adolescence, we studied post‐neonatal death in patients with CHARGE syndrome. We collected medical data on three deceased children from a follow‐up cohort of 48 CHARGE patients and retrospectively on an additional four deceased patients (age at death 11 months to 22 years). We analyzed the factors that had contributed to their death. In five patients respiratory aspiration had most likely contributed to premature death, one died of post‐operative complications, and another choked during eating. From our findings and a literature review, we suggest that swallowing problems, gastro‐esophageal reflux disease, respiratory aspiration and post‐operative airway events are important contributors to post‐neonatal death in CHARGE syndrome. Cranial nerve dysfunction is proposed as the underlying pathogenic mechanism. We recommend every CHARGE patient with feeding difficulties to be assessed by a multidisciplinary team to evaluate cranial nerve function and swallowing. Timely treatment of swallowing problems and gastro‐esophageal reflux disease is important. Surgical procedures on these patients should be combined whenever possible because of their increased risk of post‐operative complications and intubation problems. Finally, we recommend performing autopsy in deceased CHARGE patients in order to gain more insight into causes of death.  相似文献   
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