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81.
目的 探讨舒肤特对座疮的治疗作用。 方法 病人随机分为治疗组和对照组。治疗组 45例 ,男 2 8例 ,女 17例 ;对照组 45例 ,男 2 5例 ,女 2 0例。年龄 14~ 42岁 ,平均 2 4岁。病程 2周~ 6年。治疗组用舒肤特 ,对照组用2 5 %氯霉素酊 ,每日 2次 ,4~ 8周为 1疗程。每周复诊 1次。 结果 治疗组痊愈率 3 7 8% ,总有效率 84 5 % ,对照组痊愈率 17 8% ,总有效率 62 2 % ,治疗组痊愈率优于对照组 ( χ2 =10 0 2 ,P <0 0 1) ,两组总有效率差异有显著性 ( χ2=11 42 8,P <0 0 1) , 结论 舒肤特是中西药复方制剂 ,其用于治疗痤疮效果较好 ,无明显副作用。  相似文献   
82.
分娩时子宫下段MMP-9及其组织抑制剂TIMP-1的变化   总被引:1,自引:1,他引:0  
目的:探讨基质金属蛋白酶(MMP)及其组织抑制剂(TIMP)在分娩发动、宫颈成熟和扩张中的作用和机制.方法:采用ELISA方法测定子宫下段组织中MMP-9和TIMP-1的浓度.有宫缩剖宫产组56例,其中第一产程组44例,第二产程组12例.以无宫缩剖宫产组16例为对照组.结果:有宫缩剖宫产组子宫下段组织中MMP-9和TIMP-1的浓度分别明显高于无宫缩剖宫产组(P<0.05,P<0.05).第一产程组中随宫口开大,MMP-9和TIMP-1的浓度各组间无显著性差异.第二产程组MMP-9和TIMP-1的浓度分别明显高于第一产程组(P<0.01,P<0.05).结论:MMPs和TIMPs的动态变化是分娩发动、宫颈成熟和扩张过程中的重要中间环节.  相似文献   
83.
Quantitative cerebral blood flow (CBF) values can be obtained from dynamic susceptibility contrast (DSC) MR perfusion studies using the standard singular value decomposition (sSVD) deconvolution algorithm. Reports in the literature from simulation and in vivo studies suggest that CBF estimates obtained using sSVD deconvolution depend on the arterial-tissue delay (ATD). By contrast, Fourier transform (FT) deconvolution produces CBF estimates that are independent of ATD. The diagnostic reliability of quantitative CBF measurements to define areas of normal tissue flow and tissue at risk is brought into doubt by such gross sensitivity to the specifics of the deconvolution approach. This variation of CBF values with ATD is shown to be an artifact associated with the current implementation of the sSVD deconvolution algorithm. A reformulated version of the SVD deconvolution algorithm (rSVD) is presented and compared to the standard SVD algorithm through simulation and patient case studies.  相似文献   
84.
Basosquamous carcinoma of the skin is a rare malignancy with specific histopathological features of both basal cell carcinoma and squamous cell carcinoma. Some authors believe that basosquamous carcinoma is a variant of basal cell carcinoma, while others suggest that this tumour may behave more aggressively. We present a 44-year-old female patient who was diagnosed with a basosquamous carcinoma histopathologically. She had extensive ulcero-vegetative lesions, involving the anterior half of the scalp, the left orbit and the left side of the face. With this case we aim to emphasize the aggressive nature of basosquamous carcinoma and review the literature.  相似文献   
85.
The aim of this study was to investigate the effect of a moderate soft tissue trauma to the course of fracture healing in a standardized animal model. Thirty-eight Wistar rats were randomly divided into a fracture group (F, n = 19) and a group with a fracture and a soft tissue trauma (F + STT, n = 19). The fracture and the soft tissue trauma were created using an impact device with a standardized energy. All fractures were stabilized by two Kirschner wires. Three rats were measured for blood flow and sacrificed at days 1, 3, 7, and 14, and seven rats at day 28, from both groups. A three-point bending test was performed on the healed tibia after 28 days. During the first 24 h there was a reduction in blood flow, which was more pronounced in the F + STT group than in the F group. From histological sections, the shape of the callus formation, as well as the tissue distribution of newly formed bone, fibrous cartilage and fibrous connective tissue were determined. Distinctly more periosteal new bone formed and a larger callus formed at days 3 and 7 in group F compared to group F + STT. However, by days 14 and 28, the ossification and overall callus size no longer showed differences between the two groups. A fast recovery of blood flow and callus formation took place in the F + STT group, which led to similar histological and biomechanical results in fracture healing observed after 28 days between the two groups.  相似文献   
86.
目的探讨采用吻合指固有神经背侧支的邻指皮瓣修复手指远端掌侧软组织缺损的疗效. 方法 1996年10月~2004年6月,25例(32指)伴肌腱或骨组织外露的手指远端掌侧软组织缺损患者,其中男18例,女7例,年龄13~45岁.切割伤6例,冲压伤8例,机器绞伤11例.损伤部位:拇指2例,食指8例,中指5例,环指3例,小指2例,食、中指2例,中、环指2例,食、中、环、小指1例.缺损范围:1.5 cm×1.0 cm~4.0 cm×2.1 cm.损伤至就诊时间30 min~48 h.急诊行清创,采用带蒂邻指皮瓣修复,术中同时将指固有神经的背侧支与指神经残端吻合重建皮瓣感觉,术后3周断蒂.供区中厚皮片游离植皮. 结果术后皮瓣及供区均成活,创面Ⅰ期愈合.获随访6~26个月,手指指腹饱满,色泽正常,感觉恢复,两点辨别觉为5~8 mm,均无功能障碍. 结论采用吻合指固有神经背侧支邻指皮瓣修复手指远端掌侧软组织缺损不仅能修复缺损皮肤,且能重建皮瓣感觉,术式操作简便.  相似文献   
87.
Using immunohistochemical and biochemical techniques, the occurrence of endogenous opioid peptides and their receptors in normal rat bone and joint tissues was investigated. Opioid receptors were detected, quantified, and characterized in homogenates from capsule/synovium and periosteum using radioligand binding assays. Receptor binding of the nonselective opioid [3H]naloxone to tissue homogenates was stereospecific and saturable, showing similar characteristics to that of brain tissue, although with lower binding capacities. By immunohistochemistry, the neuronal occurrence of four different enkephalins was demonstrated in synovium, bone marrow, periosteum, and juxta-articular bone, whereas no neuronal dynorphin immunoreactivity was detected. Double-staining studies disclosed that enkephalins coexisted with substance P in primary afferent fibers. The applied techniques can be used to assess changes in the distribution of endogenous opioids and their receptors in joint tissues in conditions associated with pain and inflammation. The endogenous opioid system now demonstrated might be targeted and exploited therapeutically to obtain peripheral control of symptoms in joint disorders.  相似文献   
88.
1. The rotation-mediated three-dimensional reaggregate culture system is uniquely suited for studies on developmental neurotoxicity. In this system, it is possible to reconstruct central neuronal pathways and follow their development. 2. Exposure to drugs of abuse including methamphetamine and methylenedioxyamphetamine or the appetite suppressant, fenfluramine, reduces monoamines in the cultures in a dose-dependent manner and interrupts normal monoaminergic development. 3. While the monoaminergic neurones may attain normal rates of development following drug removal, the affected neurones are not capable of overcoming the drug-induced insults and a deficiency in monoamines persists throughout development. 4. In addition, the production of immortalized monoclonal hybrid cells obtained by fusion of fetal mesencephalic neurones with a neuroblastoma has yielded cell lines expressing a dopaminergic phenotype. 5. Such cells have been useful in establishing the relationship of neurotoxicity to cell lineage and can serve as models for the study of the cellular and molecular mechanisms of neurotoxicity.  相似文献   
89.
Induction of neurite outgrowth from superior cervical ganglia (SCG) by rat lymphoid tissues was studied using a tissue culture model. Neonatal rat SCG were cultured with 6–12-week-old rat thymus, spleen, or mesenteric lymph node (MLN) explants in a Martrigel layer, in defined culture medium without exogenous nerve growth factor (NGF). SCG were also co-cultured with neonatal rat heart (as positive control) or spinal cord (SC; as negative control). To determine whether inflammation affects the ability of lymphoid tissues to induce neurite outgrowth, we also examined MLN at various times after infecting rats with Nippostrongylus brasiliensis (Nb-MLN). In one series of experiments, a single lymphoid tissue explant was surrounded by four SCG at a distance of 1 mm. The extent of neurite outgrowth was determinded by counting the number of neurites 0.5 mm away from each ganglion at several time points. Adult thymus and, to a lesser extent, spleen had strong stimulatory effects on neurite outgrowth from SCG after 12 hr or more in culture. For thymus tissue, this was similar to the positive control heart explants. MLN from normal rats had minimal effect on neurite outgrowth; however, Nb-MLN showed a time-dependent enhancement of the neurite outgrowth, maximal at 3 weeks after infection. The relative efficacy of neurite outgrowth induction (heart ≥ thymus ≥ Nb-MLN ≥ spleen ≥ MLN ≥ SC) was confirmed in a second series of experiments where one SCG was surrounded by three different tissue explants. We then examined the role of 2.5S NGF, a well-known trophic factor for sympathetic nerves, in the lymphoid tissue-induced neurite outgrowth. Anti-NGF treatment of co-cultures of SCG and heart almost completely blocked the neurite outgrowth. Anti-NGF also significantly inhibited thymus- and spleen-induced neurite outgrowth, but not as effectively as heart-induced neuritogenesis (93,80, and 77% inhibition at 24 hr; 86,70, and 68% inhibition at 48 hr for heart, thymus, and spleen, respectively). On the other hand, anti-NGF inhibited only 8% of neurite outgrowth induced by 3-week post-infection Nb-MLN at 24 hr, and 41% at 48 hr. These data show that several adult rat lymphoid tissues exert neurotrophic/tropic effects. The predominant growth factor in thymus and spleen is NGF, while Nb-MLN produces factor(s) which is (are) immunologically distinguishable from NGF. These neurotrophic/tropic factors are produced during the reactive lymphoid hyperplasia that forms part of the inflammatory response against the nematode, N. brasiliensis. This suggests the possibility that cytokines produced by lymphocytes or other inflammatory cells may stimulate sympathetic neurite outgrowth in vivo. © 1994 Wiley-Liss, Inc.  相似文献   
90.
An assumption of previous models of hepatic elimination is that there is negligible axial diffusion in the liver. We show, by construction of a stochastic model and analysis of published data, that compounds which are readily diffusible and partitioned into hepatocytes may undergo axial tissue diffusion. The compounds most likely to be affected by axial tissue diffusion are the lipophilic drugs for which the cell membranes provide little resistance and which are highly extracted, thereby creating steep concentration gradients along the sinusoid at steady state. This phenomenon greatly modifies the availability of the compound under conditions of altered hepatic blood flow and protein binding. For moderately diffusible compounds, these relationships are similar to those predicted by the simplistic venous-equilibrium model. Hence, the paradoxical ability of the venous-equilibrium model to describe the steady-state kinetics of lipophilic drugs such as lidocaine, meperidine, and propranolol may be finally resolved. The effects of axial tissue diffusion and vascular dispersion on hepatic availability of drugs are compared. Vascular dispersion is of major importance to the availability of poorly diffusible compounds, whereas axial tissue diffusion becomes increasingly dominant for highly diffusive and partitioned substances.This study was supported by the National Health and Medical Research Council of Australia.  相似文献   
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