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1.
黑柴胡中新三萜皂甙的结构鉴定   总被引:3,自引:0,他引:3  
从黑柴胡(Bupleurum smithii Wolff)根中分离出10个化合物,均为首次由该植物中获得。其中二个新三萜皂甙,即柴胡皂甙k和l(saikosaponin k and l),其结构经紫外、红外、核磁共振氢谱,碳谱和质谱等波谱测定和解析,分别确定为3β,16β,23,28-四羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃木糖基-(1→2)-β-D-吡喃葡萄糖基-(1→3)-β-D-吡喃呋糖甙和3β,16α,23,28,30-五羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃葡萄糖基-(1→3)-β-D-吡喃呋糖甙。  相似文献   
2.
Summary The technique of obliquely drilling out the postero-lateral part of the cervical vertebral bodies is described. It uses the antero-lateral (retro carotico-jugular) approach to control and displace the vertebral artery postero-laterally and to expose the lateral aspect of the vertebral bodies. It provides, through a wide field and with minimal retraction of the carotid artery and the internal jugular vein, an extensive view of the anterior aspect of the spinal cord. It has already been used to treat 15 anterior lesions compressing the spinal cord including neurinomas and osteophytes.  相似文献   
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This study examined the influence of overnight storage on endothelium-independent contractions to 5-hydroxytryptamine (5-HT), endothelium-dependent contractions to NG-nitro-l-arginine methyl ester (L-NAME), and endothelium-dependent relaxations to substance P (SP) and l-arginine, using the porcine isolated splenic artery. In endothelium-intact (E+) segments from fresh porcine isolated splenic arteries or segments from the same vessels stored overnight at 4°C, either in Krebs-Henseleit saline or in Krebs-Henseleit saline containing 1 MM l-arginine, 5-HT caused concentration-related contractions that were similar under all three conditions. Overnight storage enhanced contractions of the splenic artery to L-NAME, an effect not observed if the vessels were co0-stored with 1 MM l-arginine. L-NAME failed to contract endothelium-denuded (E–) segments from fresh tissues or tissues stored overnight, indicating that its constrictor effects were endothelium-dependent. SP caused concentration-related, endothelium-dependent relaxations of the splenic artery that were inhibited by 100 gM L-NAME, indicating that the relaxations could be attributed to the stimulated release of NO from endothelial cells. Established contractions to 100 M L,NAME in E+ segments from fresh tissues, or segments from the same tissues stored overnight at 4°C, either in KrebsHenseleit saline or in Krebs-Henseleit saline containing 1 MM l-arginine, were all reversed by 1 MM l-arginine to similar extents, indicating that overnight storage did not affect endothelium-dependent dilator responses to l-arginine. Our findings indicate that overnight storage enhances endothelium-dependent contractions to L-NAME without affecting endothelium-independent contractions to 5-HT, or endothelium-dependent dilator responses to SP or l-arginine. Correspondence to: V.G. Wilson at the above address  相似文献   
5.
We describe our experience in treating 7 patients who underwent skull base reconstruction with free flap (6 latissimus dorsi, 1 rectus abdominis) between October 1996 and November 1998. Four patients underwent temporal bone resection with auricular resection, 2 patients underwent anterior and middle cranial fossa resection, 1 patient underwent frontotemporal resection. There have been no failures of the free flaps and one cerebrospinal fluid leak. We advocate free flap reconstruction after temporal bone resection with auricular resection, and after anterior or middle cranial fossa resection when local flap options are not available or with complex dead space.  相似文献   
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Leonard  JP; Quinto  CM; Kozitza  MK; Neben  TY; Goldman  SJ 《Blood》1994,83(6):1499-1506
Interleukin-11 (IL-11) is a novel multifunctional hematopoietic cytokine capable of stimulating cells of the myeloid, lymphoid, erythroid, and megakaryocytic lineages in vitro. We have tested the pleiotropic properties of this cytokine on the hematopoietic recovery of mice after a combined regimen of sublethal irradiation and carboplatin administration. This regimen results in severe myelosuppression, characterized by a prolonged period of thrombocytopenia and severe anemia. Administration of recombinant human IL-11 (rhIL-11; 250 micrograms/kg/d) had multilineage effects on bone marrow and spleen hematopoietic activity, increasing the number of megakaryocyte, erythroid, granulocyte, and macrophage progenitors compared with the vehicle-treated controls. This was reflected in the peripheral circulation by a reduction of both the platelet and hematocrit nadirs and a significantly reduced period of thrombocytopenia and anemia in the rhIL-11-treated mice. The results from this study support the broad spectrum of biologic activities that have been attributed to rhIL-11 in vitro and suggest that this cytokine may be an effective agent in the treatment of myelosuppression associated with cancer chemotherapy and bone marrow transplantation.  相似文献   
8.
In addition to AIDS surveillance, data on HIV infection are necessary to better follow the dynamics of the epidemic. We report the first results of France's mandatory anonymous HIV notification system, which is linked to a virological surveillance of recent HIV infections and of circulating HIV types, groups and subtypes. HIV notifications are initiated by microbiologists who create an anonymous code of patient's identity. Clinicians complete the notification form with epidemiological and clinical data. Notifications are sent to the local health authorities and passed to the Institut de Veille Sanitaire (InVS). Laboratories voluntarily send sera from newly diagnosed HIV infected persons on dried blood spots to the national HIV reference laboratory where an immunoassay for recent infection (< or = 6 months) and a serotyping assay for the determination of group and subtype are done. The virological results are then merged at the InVS with the information from the mandatory reporting. Of the first 1301 new HIV diagnoses reported in 2003, 43% were in women, and overall, 53% were in heterosexuals, of whom 47% were of sub-Saharan African origin. MSM accounted for 36% of male notifications. A dried blood spot was available for 64% of new HIV diagnoses. Evidence of recent infection was found for 38%, ranging from 22% in IDUs to 58% in MSM. Twenty-six percent of infections in sub-Saharan migrants were recent infections. HIV-1 accounted for 98% of all notifications: 48% of these were non-B subtypes. The first results of the HIV notification system indicate that heterosexual transmission is the predominant mode of transmission and that persons originating from sub-Saharan Africa are particularly affected. Over half of infections shown to be recently acquired were in MSM; this may indicate an increased HIV incidence in this population.  相似文献   
9.
We describe the case of a patient with chronic hepatitis B who became resistant to lamivudine and was treated successfully with adefovir dipivoxil in addition to lamivudine. Lamivudine resistance was associated with the selection of a L180M+M204V polymerase mutant. After the addition of adefovir dipivoxil, serum HBV DNA levels dropped by more than 4log(10), which was followed by HBsAg clearance after 22 months of combination therapy. Moreover, anti-HBs antibody titers rose above 1000 mIU/mL after 32 months of the new treatment regimen. In parallel, HBV DNA declined below 100 copies/mL by a quantitative real time PCR assay. Analysis of intrahepatic viral DNA showed a significant decline of total HBV DNA and cccDNA which was accompanied by a decrease of the number of infected cells expressing viral antigens below the detection limit of immunostaining. In parallel, liver histology analysis showed an improvement in both the activity index and fibrosis score. This report suggests that in patients who previously failed lamivudine therapy, proactive antiviral treatment may lead to a beneficial virological and clinical effect.  相似文献   
10.
Aims To determine the effect of age, sex and cohort on the prevalence and genetic architecture of adolescent alcohol use (AAU). Design Survey study in participants registered with the Netherlands Twin Register. Setting Twins from the general population. Participants Two cohorts (data collected in 1993 and 2005–08) of twins aged 13–15, 16–17 and 18–21 years. In 1993 and 2005–08 a total of 3269 and 8207 twins, respectively, took part. Measurements Survey data on initiation and frequency of alcohol use and quantity of alcohol consumed. Findings The prevalence of alcohol initiation increased between 1993 and 2005–08 for both males and females. The largest difference was for girls observed at ages 13–15, where the prevalence increased from 59.5% to 72.4%. We also found increases in prevalence across cohorts for quantity of alcohol consumed and non‐significant increases for frequency of alcohol use. From age 16 onwards, boys drank more frequently and larger quantities than girls. Genetic model fitting revealed that the genetic architecture of AAU did not differ between birth cohorts, nor were there differences between boys and girls. Genetic factors explained between 21% and 55% of individual differences in alcohol measures throughout adolescence. Shared environment explained between 17% and 64% of variance in alcohol use, across different age groups and alcohol measures. Conclusions In the Netherlands, the prevalence of alcohol initiation, frequency and quantity has increased in adolescents over a 15‐year period, but there are no changes in the genetic architecture of adolescent alcohol use.  相似文献   
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