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131.
羽叶三七叶中甙类成分的研究 总被引:3,自引:0,他引:3
从羽叶三七叶中分离到十三种甙类成分,经FAB-MS,13CNMR谱,双照射1HN-MR谱,1H-1H COSY谱及与标准品直接对照,证明十一种为已知化合物,分别为人参皂甙F1(Ⅰ),F2(Ⅱ),F3(Ⅲ),Rg2(Ⅳ),Ra(Ⅴ),Rd(Ⅵ),Rb1(Ⅷ),Rb3(Ⅷ),24(S)-假人参甙F11(Ⅸ),人参黄酮(Ⅹ)和珠子参甙F1(Ⅺ);另外两种为新的达玛烷型皂甙,命名为羽叶三七甙F1(Ⅻ)和F2(ⅫⅠ),并确定其化学结构。同时修正珠子参甙F3的结构。进一步阐明人参黄酮甙结构中的两个糖的连接方式。 相似文献
132.
Modulation of implantation-associated integrin expression but not uteroglobin by steroid hormones in an endometrial cell line 总被引:2,自引:0,他引:2
Widra EA; Weeraratna A; Stepp MA; Stillman RJ; Patierno SR 《Molecular human reproduction》1997,3(7):563-568
In order to test the hypothesis that integrin and uteroglobin (UG)
expression in cultured endometrial cells are affected by hormone treatment,
Ishikawa-CH endometrial cancer cells were cultured and exposed to
oestradiol or oestradiol and progesterone regimens and assayed using
immunohistochemistry. We evaluated the intensity of immunohistochemical
staining for the integrin monomers alpha(v) and beta1, the dimers
alpha(v)beta3 and alpha(v)beta6, and for the secretory protein uteroglobin
under various experimental conditions. Cells grown in control media stained
positively for the integrin monomers alpha(v) and beta1, the dimer
alpha(v)beta3, and for UG. Oestradiol and sequential
oestradiol/progesterone reversibly suppressed staining for the dimer
alpha(v)beta3. Hormone treatment had no effect on the staining of the beta1
and alpha(v) monomers or UG. The alpha(v)beta6 dimer antibody did not stain
under any experimental treatment conditions. These data indicate that
expression of the integrin complex alpha(v)beta3 is reversibly suppressed
by oestradiol in Ishikawa cells and that these cells may be a good model
for studying hormone-driven molecular changes in endometrium.
相似文献
133.
Genetic and non‐genetic factors that increase the risk of non‐syndromic cleft lip and/or palate development
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134.
Embolization of Iatrogenic Vascular Injuries of Renal Transplants: Immediate and Follow-Up Results 总被引:2,自引:0,他引:2
Roland Dorffner Siegfried Thurnher Rupert Prokesch Alexander Bankier Karl Turetschek Alice Schmidt Johannes Lammer 《Cardiovascular and interventional radiology》1998,21(2):129-134
Purpose: To evaluate the outcome in seven patients in whom iatrogenic vascular complications were treated with catheter embolization.
Methods: Angiography showed an arteriovenous fistula in six of the seven patients, a pseudoaneurysm in three patients, and an arteriocaliceal
fistula in three patients. Embolization was performed with GAW coils or microcoils in all cases. In three patients enbucrilate,
polyvinyl alcohol, or absorbable gelatin powder was administered as an adjunct to the coils.
Results: Angiographic success with total occlusion of the vascular injury was achieved in five of the seven patients and clinical
success was achieved in four of seven cases. In two cases, nephrectomy after embolization was necessary because of renal artery
occlusion or acute hemorrhage at the renal artery anastomosis, respectively. Infarction of 30%–50% of the renal parenchyma
was seen in two cases.
Conclusion: Angiographically successful embolization is not necessarily associated with clinical success. The complication rate is high. 相似文献
135.
136.
MP Busch ; JJ Korelitz ; SH Kleinman ; SR Lee ; JP AuBuchon ; GB Schreiber 《Transfusion》1995,35(11):903-910
BACKGROUND: Since the mid-1980s, blood banks in the United States have screened donors for elevated alanine aminotransferase (ALT) in an effort to prevent posttransfusion hepatitis. The present study was designed to quantitate the residual value of ALT screening following the implementation of hepatitis C virus (HCV) assays. STUDY DESIGN AND METHODS: Two approaches were used. First, a database of 2.3 million donations made by 586,507 volunteer blood donors between 1991 and 1993 was used to compare the incidence of seroconversion to hepatitis B virus (HBV) and HCV marker positivity in donors with elevated ALT values and with normal ALT values. Second, the duration of ALT elevation prior to HBV and HCV seroconversion was determined from 34 well-documented cases of posttransfusion HBV and HCV; elevated-ALT window periods were multiplied by rates of HBV and HCV incidence in donors to project the yield of ALT screening. Predictive value and cost- effectiveness analyses were also performed to compare the value of ALT screening before and after HCV screening was implemented. RESULTS: Both approaches indicate that ALT testing does not detect HBV in the window phase but does currently identify approximately 3 HCV window-phase donations per 1 million donations; this contrasts with ALT detection of approximately 1800 HCV-infectious units per 1 million donations prior to anti-HCV screening. Currently, only 8 in 10,000 donated units with elevated ALT (negative anti-HCV) are infected with HCV. The cost of continued ALT screening was estimated at $7,931,000 per quality- adjusted year of life saved. CONCLUSION: The yield, predictive value, and cost-effectiveness of ALT screening of blood donors have declined dramatically with the implementation of progressively improved anti-HCV assays. ALT screening of volunteer blood donors should be discontinued. 相似文献
137.
Increased detection of hepatitis C virus infection in commercial plasma donors by a third-generation screening assay 总被引:4,自引:0,他引:4
SR Lee ; CL Wood ; MJ Lane ; B Francis ; C Gust ; CM Higgs ; MJ Nelles ; A Polito ; R DiNello ; D Achord 《Transfusion》1995,35(10):845-849
BACKGROUND: Routine screening of blood donations with second-generation hepatitis hepatitis C virus (HCV) assays has substantially reduced the occurrence of posttransfusion hepatitis. However, following the development of third-generation assays, several studies indicated that these assays may identify HCV-infected individuals who are not identified by second-generation assays. STUDY DESIGN AND METHODS: The sensitivity of a third-generation HCV enzyme-linked immunosorbent assay (ELISA-3) was compared with a second-generation ELISA (ELISA-2) in a side-by-side study of 9936 commercial blood donors. ELISA-reactive specimens were subjected to supplemental analysis by third-generation recombinant immunoblot assay and polymerase chain reaction. RESULTS: ELISA-3 demonstrated greater sensitivity than ELISA-2, detecting 1 additional recombinant immunoblot assay-positive specimen per 2000 tested. ELISA-3 also detected 1 additional HCV-infectious polymerase chain reaction-positive unit among approximately 10,000 units screened. CONCLUSION: The incremental sensitivity achieved with ELISA-3 can be expected to eliminate approximately 20 infectious donations per week among those made by commercial donors in the United States. In accordance with previous studies, most of the improved sensitivity of ELISA-3 derives from its increased detection of anti-c33c (NS3), rather than from the inclusion of HCV antigen NS5. 相似文献
138.
S Sirrs EM Yoshida LTK Wong SR Erb SW Chung UP Steinbrecher CH Scudamore C Hartnett Y Lillquist AGF Davidson 《Paediatrics & child health》2003,8(8):497-498
A 15-year-old female with carbamyl phosphate synthetase deficiency, cystic fibrosis, and cystic fibrosis-related diabetes underwent orthotopic cadaveric liver transplantation. Metabolic control was maintained during the procedure with nutritional support and the use of intravenous sodium phenylacetate and benzoate. Her postoperative course was complicated by seizures and a transient decline in her pulmonary function tests, which returned to preoperative levels within one year of the transplant. Now, four years post-transplant, her quality of life has dramatically improved. There are only four Canadian centres with paediatric liver transplantation programs. However, expert medical care for adults with inborn error of metabolism is even more limited, suggesting that access to adult medical care is one of the many factors to be considered when liver transplantation is contemplated for patients with metabolically unstable conditions. 相似文献
139.
The acrosome reaction is an important marker for human sperm function.
Since different laboratory techniques may be used for the detection of this
exocytotic process, the purpose of the present study was to compare three
common markers [Pisum sativum agglutinin (PSA), concanavalin A (ConA),
double staining] and transmission electron microscopy for identification of
acrosomal changes. Preliminary findings had demonstrated that similar
results were achieved with Trypan Blue and Hoechst 33258 staining.
Therefore, supravital stainings were omitted. In various experiments, human
spermatozoa were treated with two concentrations (10 and 3.3 microM) of
calcium ionophore A23187 for 15, 30 and 60 min after capacitation for 3 and
6 h at 37 degrees C. The percentages of spermatozoa with acrosomal loss
detected by fluorescein isothiocyanate (FITC)-ConA were consistently lower
than those obtained by double staining or FITC-PSA, which showed comparable
results. Following 6 h of capacitation and incubation with 10 microM
ionophore for 1 h at 37 degrees C, 25.9 +/- 15.7% of all spermatozoa showed
almost complete loss of the acrosomal content. Binding of FITC- ConA to the
acrosomal region was observed in 27.0 +/- 13.2% of spermatozoa obtained
from the same sample. FITC-ConA and double staining or FITC-PSA detect
different stages of the acrosome reaction and may be helpful for a
differentiated evaluation of this sperm function.
相似文献
140.