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21.
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。  相似文献   
22.
The effect of neonatal capsaicin treatment on chemo- and/or barosensory input to the medulla was studied in 35-40-day-old rats. By means of responses evoked in the nucleus tractus solitarius by stimulating the ipsilateral sinusal nerve, the excitability of slow-conducting carotid afferent fibers and the effect of substance P microinjection into the fourth ventricle were evaluated. Neonatal capsaicin resulted in reduced amplitude of the late component of the evoked responses, increased chronaxie values in the strength-duration paradigm, and increased sensitivity of evoked responses to the inhibitory effect of intracerebroventricular administered substance P. The results indicate that capsaicin given early in life leads to functional disturbances of chemo- and/or barosensory input to the nucleus tractus solitarius, involving both the slow-conducting primary afferents and the receptors for substance P of the second-order cells of the sensory pathway.  相似文献   
23.
PCR-based hybridization methods have been used to show that some women with normal cytology are carriers of HPV DNA of the types strongly related to cervical cancer. How these women should be managed remains unclear. This chapter selectively reviews reports which have estimated type-specific HPV prevalence in relation to the presence or absence of morphological signs of HPV infection. Overall, these reports indicate that among women who were identified as carriers of HPV DNA (by PCR-based methods) and who also had a normal cytological smear, the HPV type detected in the majority of instances was a high-risk viral type for cervical cancer (HPV types 16/18 = 44.7%; HPV types 31/33/35 = 8.1%; other and unknown types = 37.9%). This suggests that screening programmes which include PCR-based HPV detection could reduce the false negative rates currently reported by screening programmes based on cytology alone.  相似文献   
24.
A two way view of gender bias in medicine.   总被引:6,自引:3,他引:3  
  相似文献   
25.
ELISA for quantitation of L-selectin shed from leukocytes in vivo.   总被引:13,自引:0,他引:13  
L-selectin is a cell surface receptor on granulocytes, lymphocytes and monocytes that is responsible for the initial attachment of leukocytes to endothelium. The extracellular domain of L-selectin is proteolytically shed from leukocytes following cellular activation in vitro. The shed form of L-selectin (SL-selectin) is functionally active and at high concentrations can inhibit leukocyte attachment to endothelium. Therefore, an ELISA was developed to quantitate the levels of SL-selectin in biological fluids, biopsy specimens and during recombinant protein production. This simple, quantitative sandwich ELISA uses two monoclonal antibodies directed against the extracellular domain of SL-selectin. The assay has a detection range of 5-1300 ng/ml, is precise and sensitive. The ability of this assay to detect SL-selectin in serum, plasma, and culture supernatant fluid was demonstrated and it was used to quantitate circulating SL-selectin in normal and patient sera. Patients with sepsis and HIV infection showed markedly elevated SL-selectin levels in serum. Thus, the ELISA should prove useful both for laboratory purposes as well as in the diagnostic evaluation of patients with inflammatory diseases.  相似文献   
26.
This study was carried out to evaluate the effects of low-level laser irradiation on experimental lesions of articular cartilage. A standard lesion was practised on the femoral trochlea of both hindlimbs of 20 clinically normal Californian rabbits. These animals were divided into two groups of 10 individuals each, depending on the laser equipment used for treatment. Onc group was treated with He-Ne laser (8 J cm-2, 632.8 nm wavelength) and the other with infra-red (IR) laser (8 J cm-2, 904 nm wavelength). In both groups, five points of irradiation to the right limb alone were irradiated per session for a total of 13 sessions, applied with an interval of 24 h between sessions. These points were the following: left and right femoral epicondyles, left and right tibial condyles and the centre of articulation. The distance between these points was approximately 1 cm. The untreated left limb was left as a control. During treatment, extension angle and periarticular thickness were considered. At the end of the treatment, samples were collected for histopathologi-cal study and stained with: Haematoxylin-Eosin, PAS and Done. The results show a statistically higher anti-inflammatory capacity of the IR laser (p < 0.0001). The functional recovery was statistically similar for both treatments (p < 0.176). Histological study showed, at the end of the treatment, hyaline cartilage in the IR group, fibrocartilage in the He-Ne group and granulation tissue in the control limbs. Clinical and histological results indicated that this laser treatment had a clear anti-inflammatory effect that provided a fast recuperation and regeneration of the articular cartilage.  相似文献   
27.
28.
A 28-year-old woman with pulmonary atresia underwent a modified Fontan procedure that utilized a valved aortic homograft; she developed stenosis of the distal anastomosis between the homograft and the pulmonary artery. Because of the increased risk of reoperation, balloon angioplasty of this stenotic lesion was performed successfully. In the subsequent 11 months she has remained asymptomatic. Balloon angioplasty was a successful alternative to reoperation in this patient.  相似文献   
29.
Carcinoma of the hepaticopancreatic ampullar region: role of US   总被引:3,自引:0,他引:3  
Hepaticopancreatic ampullar tumors are so called because they are located at the confluence of the bile duct, pancreatic duct, and duodenum. Jaundice is an early sign of the disease and often leads to early diagnosis and favorable prognosis compared with other tumors that occur in this area. Of eight patients who underwent ultrasound (US) in the past 5 years, six (75%) were found to have tumor. The sizes of the tumors ranged from 1.6 to 2 cm. An intraluminal, polypoid mass in the distal part of the common bile duct was seen in four patients. In the other two patients, a sharply delineated mass gave rise to abrupt termination of the distal duct. Improved US resolution, more experience with this modality, and accurate diagnosis of these tumors with US will contribute to improved detection and prompt treatment.  相似文献   
30.
We have monitored the expression of interleukin-7 (IL-7) in the developing embryonic mouse thymus by a combination of quantitative polymerase chain reaction (PCR) and immunofluorescence microscopy. A strong specific signal for IL-7 mRNA was detected by day 12 in the developing fetal thymus. IL-7 mRNA was found to be maximally expressed on day 15, and then decreased over the next 5 days. Immunofluorescence staining of fetal thymus sections using an anti-IL-7 antibody confirmed these PCR data. IL-7 protein expression was first detected at day 13 of development. At 14 days the intensity of the staining increased by a factor of three and stayed at this level over the next 4 days. The same anti-IL-7 antibody used for immunofluorescence, blocked the proliferation of fetal thymocytes in organotypic cultures. In addition, we detected mRNA coding for IL-2 and SCF (also known as the steel factor or KL) in embryonic thymocytes. The implications of these findings for early thymocyte growth are discussed.  相似文献   
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