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991.
赤芝孢子粉三萜化学成分研究   总被引:15,自引:1,他引:15  
陈若芸  于德泉 《药学学报》1991,26(4):267-273
自赤芝(Ganoderma lucidum Karst)孢子粉酸性部分分离得到一个新的四环三萜化合物,命名为ganosporeric acid A(1),根据光谱(IR,1HNMR,13CNMR和MS)分析确定其结构为Ⅰ所示。同时还分到四个已知化合物:ganoderic acid B(Ⅱ),ganodefic acid C(Ⅲ),ganoderic acidE(Ⅳ),和ganodermanontriol(Ⅴ)。这些化合物均为首次从赤芝孢子粉中得到。  相似文献   
992.
天然产物加锡果宁(edulinine)具有镇痛,麻醉、抗惊厥等中枢神经抑制活性。作者在其结构基础上,采用了Topliss和Austel等的定量药物设计方法,合成了一系列加锡果宁类似化合物1V,V,并探讨了其生物作用。经药理筛选表明,个别化合物具有比加锡果宁更强的中枢神经抑制作用。  相似文献   
993.
乌拉尔甘草中新香豆素的化学研究   总被引:4,自引:0,他引:4  
甘草是一味重要的传统中药,为临床广泛使用。多年来国内外学者对其化学成分的研究颇为重视。近来,用不同溶剂对甘草进行分步提取,以酶和受体生物学指标进行监测,发现乌拉尔甘草(Glycyrrhiza uralensis Fisch)的二氯甲烷提取物对安定受体,胆囊收缩素受体以及二氢还原酶具有明显的抑制作用。为了寻找其中的有效成分,我们对该部分进行了化  相似文献   
994.
PURPOSE. In ocular kinematics, the primary position (PP) of the eye is defined by the position from which movements do not induce ocular rotations around the line of sight (Helmholtz). PP is mathematically linked to the orientation of Listing's plane. This study was conducted to determine whether PP is affected differently in patients with clinically diagnosed congenital (conTNP) and acquired (acqTNP) trochlear nerve palsy. METHODS. Patients with unilateral conTNP (n = 25) and acqTNP (n = 9) performed a modified Hess screen test. Three-dimensional eye positions were recorded with dual search coils. RESULTS. PP in eyes with acqTNP was significantly more temporal (mean: 21.2 degrees ) than in eyes with conTNP (6.8 degrees ) or healthy eyes (7.2 degrees ). In the pooled data of all patients, the horizontal location of PP significantly correlated with vertical noncomitance with the paretic eye in adduction (R = 0.59). Using a computer model, PP in acqTNP could be reproduced by a neural lesion of the superior oblique (SO) muscle. An additional simulated overaction of the inferior oblique (IO) muscle moved PP back to normal, as in conTNP. Lengthening the SO and shortening the IO muscles could also simulate PP in conTNP. CONCLUSIONS. The temporal displacement of PP in acqTNP is a direct consequence of the reduced force of the SO muscle. The reversal of this temporal displacement of PP, which occurs in some patients with conTNP, can be explained by a secondary overaction of the IO muscle. Alternatively, length changes in the SO and IO muscles, or other anatomic anomalies within the orbit, without a neural lesion, may also explain the difference in location of PP between conTNP and acqTNP.  相似文献   
995.
PURPOSE: To report a patient with Neisseria meningitidis endophthalmitis without associated meningitis with full visual recovery, with early detection of the microorganism using polymerase chain reaction (PCR) analysis. DESIGN: Retrospective, observational case report. PARTICIPANTS: One patient with endogenous endophthalmitis. METHODS: Polymerase chain reaction analysis and culture of the intraocular fluid sample. Polymerase chain reaction analysis was performed with a universal (16S rRNA) primer set to detect bacterial DNA, and subsequently a specific probe was used to detect Neisseria species DNA. RESULTS: The 16S rRNA primers detected bacterial DNA, the specific probe detected Neisseria species DNA, and culture was positive for Neisseria meningitidis serotype C. CONCLUSIONS: A universal bacterial PCR can be very helpful for the diagnosis of endogenous bacterial endophthalmitis at an early stage of the disease.  相似文献   
996.
Ninety-seven patients with breast cancer recurring in a previously irradiated area (mean dose 44 Gy) were reirradiated in combination with hyperthermia and had evaluable tumor responses. In the reirradiation series, radiotherapy was given twice weekly in most patients, with a fraction size varying from 200 to 400 cGy, the total dose varying from 8 to 32 Gy. Hyperthermia was given following the radiotherapy fractions. The combined treatment resulted in 35% complete and 55% partial responses. Duration of response was median 4 months for partial response and 26 months for complete response, respectively. The median survival time for all patients was 12 months. Acute skin reaction was mild, with more than moderate erythema in only 14/97 patients. Thermal burns occurred in 44/97 patients, generally at sites where pain sensation was decreased, and therefore they did not cause much inconvenience. In the 19 patients who survived more than 2 years, no late radiation damage was observed. When patients who received a "high dose" (greater than 29 Gy and hyperthermia) were compared with those who received a "low dose" (less than 29 Gy and hyperthermia), a higher complete response rate was observed in the high dose group (58% vs. 24%), whereas no difference in acute toxicity was found. We conclude that reirradiation with 8 x 4 Gy in combination with hyperthermia twice weekly is a safe, effective and well tolerated method for palliative treatment of patients with breast cancer recurring in previously irradiated areas.  相似文献   
997.
OBJECTIVE: Caregiving has been described in the literature as a risk factor for ill health in the carer. This controlled, prospective study examines the course of physical and mental health problems in parents of adolescent survivors of a mass burn incident. METHODS: Health information was extracted from electronic medical records. Continuous data were available for 1 year before and 4 years after the fire. Cohorts comprised 273 parents of survivors with burns, 199 parents of survivors without burns, and 1756 controls. Post-fire increases in health problems were compared by means of logistic regression. RESULTS: Parents of burn victims were more likely to present mental health problems during the first 2 years after the incident, when compared to the baseline. Moreover, they were more likely to present cardiovascular health problems in every year following the disaster, compared to the baseline. Increases observed in mental and cardiovascular health problems were significantly larger in parents of burn victims compared to controls. Risk factors for presenting mental health problems were female gender of the parent and a large burn size in the child. Lower socioeconomic status and female gender of the parent predicted cardiovascular health problems. CONCLUSION: Evidence gained in longitudinal studies informs on which health problems are most likely to develop in parental caregivers. In the interest of both parent and child, a family-oriented approach is proposed.  相似文献   
998.
999.
Based on the good results of re-irradiation plus hyperthermia in breast cancer recurrences on the chest wall, it was decided to offer similar treatment to a patient with recurrent metastatic breast cancer in the orbital region. A female patient was diagnosed in 1997 with breast cancer stage T4N0M0. She was treated with six neo-adjuvant chemotherapy courses and mastectomy, followed by hormonal treatment. In December 1998, she was diagnosed with metastatic disease in the medial upper quadrant of the left orbit. This was excised, followed by 40 Gy radiotherapy. Nine months later, the tumour had recurred in the left orbit at the margin of the radiotherapy field. This again was treated with surgery, followed by 30 Gy radiotherapy. Two months thereafter, the eyelid tumour progressed and hormonal therapy was changed, without an effect on the eyelid tumour. Screening gave no evidence of tumour activity elsewhere. The patient preferred treatment with re-irradiation plus hyperthermia to a surgical approach. Eight fractions of 4 Gy were given in 4 weeks, combined with once weekly hyperthermia. One week after treatment, the tumour had regressed completely. The patient died 22 months following treatment. Until last follow-up, a few weeks before death, the patient mentioned a dry left eye for which she used eyedrops, an unchanged vision and no further difficulties. On examination, there was epilation of the eyelids, a slight conjunctival oedema, no subcutaneous fibrosis and no evidence of tumour regrowth. For this patient, a surgical approach would have resulted in loss of the left eye. Toxicity of re-irradiation plus hyperthermia might lead to either a loss of vision or a delayed loss of her left eye due to treatment-induced toxicity. The chosen local treatment resulted in a very good palliative effect, which lasted for the patient's remaining lifetime of 22 months.  相似文献   
1000.
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