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21.
白术植株性状的相关性研究   总被引:3,自引:0,他引:3  
付顺华  陈斌龙  何福基  吴家森 《中药材》2003,26(10):695-697
通过浙江省白术栽培群体的调查,研究了白术的生长特性及不同立地类型对生长的影响,并分析了白术性状与根茎的相关性。结果表明:白术群体的分化很大;植株性状之间存在显著的相关性,一些性状与根茎商品等级也存在相关性。本结果可为白术良种选育提供有用依据。  相似文献   
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BACKGROUND: Tranexamic acid, an inhibitor of fibrinolysis that blocks the lysine-binding site of plasminogen to fibrin, has been reported to reduce intraoperative and postoperative blood loss in patients undergoing total hip arthroplasty with cement. However, there have been few reports describing the effects of tranexamic acid on blood loss during and following total hip arthroplasty without cement. METHODS: We investigated the effects of tranexamic acid in twenty-one patients who underwent staged bilateral total hip arthroplasty without cement for the treatment of osteoarthritis of the hip. The average interval between the two procedures was 16 +/- 16 months. On one side, 1000 mg of tranexamic acid was administered intravenously five minutes before the skin incision. On the other side, tranexamic acid was not administered. Baseline hemoglobin and hematocrit values were obtained three weeks before each arthroplasty. The volume of postoperative blood loss was recorded at two-hour intervals for the first twelve hours and then again at twenty-four hours, and the values were compared between the two groups. RESULTS: The total intraoperative blood loss in the tranexamic acid group (607 +/- 298 mL) was similar to that in the control group (633 +/- 220 mL). The postoperative blood loss in the tranexamic acid group was significantly lower than that in the control group at all time-points during the first twenty-four hours (p < 0.001 for all comparisons). The greatest reduction in blood loss was observed during the first four hours after surgery in the tranexamic acid group (p < 0.01). CONCLUSIONS: In patients undergoing total hip arthroplasty without cement, preoperative administration of tranexamic acid is associated with decreased postoperative blood loss during the first twenty-four hours, especially during the first four hours after surgery.  相似文献   
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Specialized antigen-presenting cells (APC), known as dendritic cells (DC), play a pivotal role in initiating primary immune responses. It has been reported that several vector systems, including adenoviral vectors, retroviral vectors, Hemagglutinating Virus of Japan (HVJ)-related vectors, and electroporation, are able to transduce genes into mouse and human DC. This has not been achieved for rat DC. To our knowledge, there is no direct evidence to support the view that the currently used vector systems are able to transduce genes into mature DC. Because most, if not all, gene transfer studies investigating DC or DC-related cell populations are carried out using heterogeneous groups of cells, it is therefore very important to determine to what extent gene transduction occurs in rat DC, and also selected mature DC (CD161a+ fully mature DC). In this study, we provide evidence that none of 4 vector systems are able to transfer genes into fully mature rat DC, which are derived from bone marrow cells (BMC), driven by Flt3/Flk2 ligand and interleukin (IL)-6, and purified by CD161a. Nevertheless, the most efficient gene transduction was observed in the developing DC progenitor cells during the long-term culture of rat BMC, and its gene expression was successfully achieved after 2 weeks of culture only with a human immunodeficiency virus (HIV)-based lentiviral vector system. The most critical time point for lentiviral gene transduction was around the 7th day from the beginning of culture with lentiviral vectors. Rat peritoneal exudate cells (PEC) and another cell line (K562) were easily transducted by adenoviral vectors and lentiviral vectors.  相似文献   
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To determine the origin of dotlike epithelial membrane antigen (EMA) immunoreactivity of ependymoma, which is consistent with the eosinophilic globular body in hematoxylin and eosin (H&E) stain, an immuno-electron microscopic study was undertaken. The usefulness of antigen retrieval pretreatment in detecting the dotlike EMA immunoreactivity in ependymomas was also studied. The materials were 29 ependymomas, 7 autopsy brains as a normal control, and 50 brain tumors of various types. The study confirmed that most of the brown dots in EMA immunostain in ependymoma represented microlumina of tumor cells. In ependymomas, plain EMA immunostaining showed dotlike positivity in only six cases (21%), and antigen retrieval pretreatment increased the number of positives up to 26 cases (90%). Antigen retrieved CD99 detected 23 positive cases (80%) in ependymomas. On the basis of the results, although some false positive findings were raised by antigen retrieval pretreatment, the authors positively recommend adoption of the technique, especially when ependymoma remains as one of the differential diagnoses of the tumor.  相似文献   
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Purpose. The object of this work was to investigate the mechanism of how the surface geometric structure of flow agents affects on the flowability of pharmaceutical powder mixtures. Methods. Nonporous and porous silicas were mixed with directly compressible fillers as flow promoting agents. The geometric structure of flow agents was investigated by gas adsorption and laser diffraction analysis. Flowability was evaluated with Carr's index measurement. Adhesion force between fillers and flow agents was determined using atomic force microscopy. Results. Flowability was improved with the addition of both nonporous and porous flow agents. In the case of nonporous flow agents, effect to promote flowability decreased with the increase of particle diameter, whereas porous flow agents highly improved flowability independent of particle diameter. Atomic force microscopy measurement found that the adhesion force between a porous agent and filler was smaller than that between a nonporous agent and filler. Conclusions. Enhancement of flowability varies depending on the geometric structure of flow agents. Porous flow agents improve flow properties more than nonporous agents, because porosity is highly contributed to reduction of adhesion force between particles.  相似文献   
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Docetaxel is an excellent agent with a high antitumor effect for the treatment of advanced/recurrent breast cancer. A 55-year-old female with metastatic liver tumors from breast cancer showed a remarkable response to intra-arterial administration of docetaxel (20 mg/week, or 40 mg/2 weeks). Since CT and MRI imaging revealed multiple metastases in the liver, intra-arterial chemotherapy was selected. No critical side effect was found during this chemotherapy. A CT scan 3 months after chemotherapy showed a partial response. We conclude that this intra-arterial chemotherapy using docetaxel will be safe and useful for liver metastases from breast cancer.  相似文献   
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Polaprezinc [N-(3-aminopropionyl)-L-histidinato zinc] (PZ), an anti-ulcer drug, is a chelate compound consisting of zinc and L-carnosine. PZ has been shown to prevent gastric mucosal injury. In the present study, we investigated the inhibitory effect of PZ on indomethacin (IND)-induced apoptosis in a rat gastric mucosal cell line, RGM1. Pretreatment with PZ suppressed caspase-3 activation and subsequent apoptosis in the cells exposed to 500 microM IND in a dose-dependent manner, and 50 microM PZ exhibited the maximum inhibitory effect. Among PZ subcomponents, zinc but not L-carnosine played a pivotal role in this antiapoptotic function. PZ did not affect mitochondrial cytochrome c release upstream of caspase-3 activation in the IND-induced apoptotic signal pathway. Treatment with 500 microM IND evidently produced reactive oxygen species (ROS) in RGM1 cells. However, PZ did not scavenge ROS in IND-treated cells. Moreover, N-acetylL-cysteine, a potent antioxidant, inhibited ROS generation but did not suppress apoptosis in RGM1 cells exposed to IND. These observations demonstrate a novel pharmacological action of PZ; i.e., that PZ, and in particular its zinc subcomponent, inhibits apoptosis via inhibition of caspase-3 activation but not antioxidant activity.  相似文献   
30.
Endoscopic ultrasonography   总被引:2,自引:0,他引:2  
EUS has many advantages over x-ray and other endoscopic procedures for the detection of lesions located in the wall of the GI tract. In the oesophagus, invasion of cancer and spread to lymph nodes can be visualized by EUS before surgery. In the stomach, the invasion depth of cancer and the therapeutic effect of laser irradiation to early cancer can be studied. EUS may also be useful in the evaluation of chemotherapy in malignant lymphoma. In benign diseases of the GI tract, EUS can provide important information about submucosal tumours. It can improve the differential diagnosis of malignant and benign submucosal tumours. EUS will also contribute to the elucidation of the pathogenesis of giant folds developing in the stomach. In addition, EUS is beneficial in the diagnosis of chronic pancreatitis, pancreatic cyst, pancreatic cancer, cancer of the papilla Vateri and diseases of the biliary tract. In conclusion, we feel that endoscopic ultrasonography may prove to be a useful technique in the diagnosis of intra- and extramural lesions of the GI tract, but comparisons with conventional imaging procedures should be performed.  相似文献   
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