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81.
目的:探讨青少年特发性脊柱侧弯(adolescent idiopathic scoliosis,AIS)胸腰椎生理曲度变化情况以及不同类型侧弯之间胸腰椎生理曲度的差异。方法:自2017年1月至2021年12月回顾性分析305例脊柱全长正侧位X线片的青少年患者,根据有无侧弯分为正常组和侧弯组。正常组179例,男79例,女100例;年龄10~18(12.84±2.10)岁。侧弯组126例,男33例,女93例;年龄10~18(13.92±2.20)岁。观察并比较两组Risser征、胸椎后凸角(thoracic kyphosis,TK)与腰椎前凸角(lumbar lordosis,LL),并分析比较不同性别、不同程度侧弯与不同节段侧弯TK值与LL值。结果:侧弯组在女性比率(P=0.001)、年龄(P<0.001)方面均明显高于正常组;Risser征方面,正常组低级别骨化程度比率明显高于侧弯组(P=0.038)。侧弯组TK值明显小于正常组(P<0.001),而两组LL值比较,差异无统计学意义(P=0.147)。男性与女性之间比较,TK值与LL值差异无统计学意义。轻度侧弯TK值明显大于中度侧弯(P<0.05),但LL值比较,差异无统计学意义(P>0.05)。不同节段侧弯之间TK值与LL值比较,差异均无统计学意义(P>0.05)。结论:胸椎与腰椎生理曲度均与性别无关;AIS患者胸椎生理曲度变小,但是腰椎生理曲度基本不变。轻度AIS患者的胸椎生理曲度大于中度AIS患者,但是腰椎生理曲度在轻中度患者之间几乎无差异,且与正常青少年相似。AIS患者胸腰椎生理曲度变化可能与脊柱前柱相对生长过快有关,其具体机制有待进一步研究。  相似文献   
82.
应用自动血细胞计数仪检测ITP患者脾动脉栓塞前后不同时期血小板的变化。结果栓塞后患者血小板计数(PLT)和平均血小板体积(MPV)的变化呈负相关,但PLT恢复正常后,MPV仍高于正常。提示脾动脉栓塞后血小板计数增高的机理不同于激素治疗。  相似文献   
83.
Vitrectomy for macular pucker and vitreomacular traction syndrome   总被引:3,自引:0,他引:3  
During the course of a so-called posterior vitreous detachment, a thin layer of the posterior vitreous cortex often remains adherent to the underlying retina. Tangential stretch of this vitreous pseudomembrane may cause vitreomacular traction syndrome, edema, and macular hole formation. The same process appears to underlie the development of true epimacular membranes (idiopathic macular pucker). Vitrectomy is generally agreed to be the most appropriate treatment for these clinical situations. We evaluated the incidence of vitreomacular adhesion and of visual improvement after vitrectomy of eyes with macular pucker (group 1; n=60) and vitreomacular traction syndrome (group 2; n=50). Vitreomacular attachment was assessed during vitrectomy under the condition of continuous air infusion. In the two groups, complete or partial vitreous attachment to the macula was observed in 57.4% and 74%, respectively. We conclude that vitreomacular adhesion is a common feature of the two clinical situations. Visual improvement was achieved in 73% of both groups. High rates of postoperative visual acuities of 20/50 or better (60.6% in group-1; 65.7% in group-2 cases) occurred only in eyes with preoperative values of 20/100 or better. It is reported that the visual outcome of vitreoretinal surgery for the two clinical conditions deteriorates with increasing duration after initial manifestation. Vitrectomy should not be postponed in patients who complain of disturbing visual symptoms such as reduced visual acuity, metamorphopsia and disturbance of binocular reading. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
84.
Summary Total -adrenoceptor density and 1- and 2-subtype distribution in right and left atria and in different ventricular regions from 14 failing and seven nonfailing human hearts have been compared. End-stage heart failure was due to idiopathic dilated cardiomyopathy (n=8) or ischaemic cardiomyopathy (n=6).In nonfailing hearts the total -adrenoceptor density was similar in the right and left atria and in all the ventricular regions studied (about 70 to 80 fmol/mg protein). The 1:2-adrenoceptor ratio in both nonfailing atria was similar (about 70:30%) and was significantly smaller than in the different regions of both ventricles (about 80:20%). The 1-subtype density was similar in nonfailing atria and ventricles (about 55 fmol/mg protein). The 2-subtype density was significantly higher in the right and left atrium (about 25 fmol/mg protein) than in both ventricles (about 15 fmol/mg protein).In patients with end-stage heart failure due to idiopathic dilated cardiomyopathy or ischaemic cardiomyopathy the total -adrenoceptor density was reduced by 50–60% in all regions. On the other hand, the 1- and 2-subtype distribution differed with the cause of heart failure. In patients with idiopathic dilated cardiomyopathy, the 1-adrenoceptor density was lower in all regions, but the 2-adrenoceptor density was not significantly reduced. In patients with ischaemic cardiomyopathy both 1- and 2-adrenoceptors were reduced in all regions.It is concluded that downregulation of -adrenoceptors in patients with end-stage idiopathic dilated cardiomyopathy or ischaemic cardiomyopathy occurs uniformly throughout the heart. The results support the hypothesis that changes in -adrenoceptor subtypes may be related to the cause of heart failure.  相似文献   
85.
The effectiveness of medical treatment for idiopathic oligozoospermia (IO) has been at best doubtful until now and a logical consequence of this unsatisfactory situation has been the partial displacement of this approach by assisted reproduction techniques. This state of affairs has resulted from insufficient investigation, inappropriately designed clinical trials and consistent disregard for the principles of evidence-based medicine. Protocol-related shortcomings and wrong interpretation of the data available have also been some of the all too frequent problems encountered in this therapeutic approach. In this rather misty situation, it appears that, of the therapeutic agents used so far, follicle stimulating hormone (FSH) (mainly FSH-secretagogues) may exert some beneficial effects on a number of biological endpoints related to spermatogenesis and sperm maturation. The short and medium term prospects of medical treatment for IO rest mainly with improvement of investigative procedures to a higher degree of sophistication, with emphasis placed on identifying the causes rather than the results of dysfunction so that a better selection of candidates can be made. Moreover, the introduction of prognostic indices for evaluation of the beneficial effects of a therapeutic agent may be of paramount importance. Finally, a better assessment of the preparations available and, possibly, the introduction of new more specific agents may also be an important step forward in this field. This type of large-scale effort should not be left to individual investigators or special centres working independently, but it may come under the auspices of a central regulating agency so that undisputed results from large, multicentre and uniform studies might be obtained, if medical treatment is to remain a good option. In this context, it may also be emphasized that andrology's main task should always be to treat the male with the problem rather than his healthy female partner, whenever this is possible.  相似文献   
86.
观察牛角地黄冲剂对大鼠免疫性血小板减少模型血栓素A2(TXA2)、前列环素I2(PGI2)的影响.将100只SD大鼠随机分成正常对照组、模型对照组、强的松对照组、牛角地黄冲剂高剂量组、牛角地黄冲剂低剂量组.除正常组外,各组均以注射免抗大鼠血小板血清(APS)造模,分别灌药和蒸馏水,每日1次,连续11天,分别在第7天和第11天各测一半大鼠血浆血栓素B2(TXB2)、6-酮-前列腺素F1α(6-keto-PGF1α)值,并作骨髓涂片检查.结果显示强的松组6-keto-PGF1α水平明显高于正常组水平(P<0.05)而牛角地黄冲剂高剂量组6-keto-PGF1α浓度明显高于模型组,且接近正常组水平.而各组TXB2水平改变均不显著.说明牛黄地黄冲剂有改善ITP出凝血功能低下的作用,且不改变机体生理平衡.  相似文献   
87.
目的探讨静脉丙种球蛋白(IVIG)加地塞米松治疗小儿特发性血小板减少性紫癜(ITP)的疗效及护理。方法对34例ITP患儿随机分为激素组和静脉丙种球蛋白加地塞米松组(简称丙球组)。结果丙球组出血症状改善迅速,血小板上升时间、峰值时间较激素组明显缩短,两组比较差异有显著意义。结论静脉丙种球蛋白加地塞米松治疗TIP疗效显著。  相似文献   
88.
The frequency and treatment of children with chronic idiopathic thrombocytopenic purpura in Sweden were characterized using a national enquiry based on a questionnaire. Seventy-five children diagnosed as having chronic idiopathic thrombocytopenic purpura on 1 September 1993 were identified. The prevalence in children between 0.5 and 15.5 years of age was calculated to be 4.6/100 000. The median age at the time of diagnosis was 5 years and the male/female ratio was 1:1.2. Almost half of the patients (43%) were not treated at all during the disease. Steroids (43%) and intravenous immunoglobulin (25%) were most commonly used. Only two children were splenectomized.  相似文献   
89.
Case: We present a case of HELLP syndrome occuring in a patient who at the age of 8 years had undergone a splenectomy for idiopathic thrombocytopenic purpura. She was diagnosed as having HELLP syndrome 37 weeks of gestation and had a cesarean section. Received: 4 June 1996 / Accepted: 7 October 1996  相似文献   
90.
In this report an attempt has been made to discuss some of the issues pertinent to myelofibrosis complicating chronic myeloproliferative disorders (CMPDs) that are significantly associated with megakaryocyte function. In this context, biochemical, clinical and particularly morphological features were reviewed. Morphological findings based on elaborate techniques were in keeping with the assumption that in chronic myeloid leukemia (1) the number of CD61-positive megakaryocytes, and in particular their precursors were the parameters most closely associated with myelofibrosis (2) an increased content of reticulin fibers in follow-up biopsies significantly correlated with laboratory data indicative of a high tumor burden (anemia, peripheral blasts, hepatosplenomegaly) and thus a more advanced stage of the disease process (3) even a slight increase in reticulin, i.e. doubling of the normal fiber density was associated with a worse prognosis independent of therapeutic regimens given (4) Dynamics of myelofibrosis was significantly influenced by treatment. In this context, calculation of the myelofibrosis progression index (MPI) revealed a higher score following interferon therapy compared with busulfan. In addition, in idiopathic myelofibrosis (5) the evolution of myelofibrosis was unpredictable and according to the MPI, progression occurred at a relatively low rate (6) proliferation and dilatation of sinusoids accompanying intravascular hematopoiesis and collagen type IV deposits were predominant features in later (fibro-osteosclerotic) stages in the course of disease (7) transmural migration of megakaryocytes demonstrated by three dimensional reconstruction revealed a mole-like tunneling through the thickened sinusoidal wall. A very careful assessment of the numerous correlations between bone marrow features and laboratory data will allow clinicians and pathologists to gain a better insight into the mutual relationships between hematological and morphological findings in CMPDs.  相似文献   
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