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111.
本文用X线摄片的方法,对西宁地区胎龄为17—36周的60例胎儿脊柱的骨化及生长动态进行了研究。结果:1、提供了高原地区人胎儿脊柱长轴生长发育的资料。脊柱各段以胸段为最长,其次为腰、颈、骶段。2、计算出胎龄与脊柱各段长度间的回归方程,据此可以胎龄推算脊柱的长度,反之亦可以脊柱的长度估计胎龄。3、报道了颈、骶、尾段亿发骨化点出现顺序的规律。  相似文献   
112.
 In order to determine the dynamics of hematopoietic cell turnover, proliferative activity and incidence of apoptosis (programmed cell death) were evaluated in bone marrow trephine biopsies. Selection of patients (20 in each group) included in addition to a control group, idiopathic thrombocytopenia (ITP), reactive thrombocytosis (TH), secondary polycythemia-smokers' polyglobuly (PG), primary (essential-hemorrhagic) thrombocythemia (PTH), polycythemia vera (PV), and finally acute myeloid leukemia (AML). Apoptosis was demonstrated by the in situ end-labeling technique (ISEL) and proliferative activity by applying the monoclonal antibody PC10 raised against proliferating cell nuclear antigen (PCNA). To assess dynamic features of hematopoiesis, an index was calculated consisting of the ratio between PCNA-positive nuclei and the apoptotic cell fraction. This factor was termed the hematopoietic turnover index (HTI). Morphometric analysis revealed that the HTI was significantly increased in AML and PV. According to cell culture studies both disorders are characterized by either a prevalent proliferation of the myeloid or erythroid cell mass. On the other hand, PG, PTH, and TH showed no relevant enhancement of this index in comparison to the control specimen. In vitro experiment results are in keeping with the finding that PG and PTH are not associated with a significant expansion of the erythroid lineage (CFU-E). Similar to ITP and TH, in PTH megakaryocyte proliferation (CFU-MEG) is the predominant feature of cell turnover. Differences between PTH and TH are in line with the reduced in vitro formation of CFU-MEG in the latter disorder. In conclusion, our in situ study on turnover rates of the bone marrow in various neoplastic and reactive lesions extends previous experimental data on hematopoietic cell kinetics. Received: 10 March 1997 / Accepted: 18 May 1997  相似文献   
113.
A case of primary non-Hodgkin's lymphoma (NHL) of the mandible with unusual radiographic presentation is reported. The panoramic radiography revealed diffuse widening of the right mandibular canal with ill-defined margins and absence of edge sclerosis. Computed tomography showed infiltration of the superior portion of the canal with involvement of the vestibular cortex of the bone and of the alveolar ridge. Correspondence to: M. Bertolotto  相似文献   
114.
Aim: Our aim was to compare the outcome in subsequent frozen embryo replacement cycles in four groups of patients who had elective cryopreservation of all their embryos because they were considered to be at increased risk of developing severe ovarian hyperstimulation syndrome. Design: Sixty-two (91%) of 68 IVF cycles (68 patients) in which elective cryopreservation of all embryos was performed were analyzed. All patients continued on the GnRH agonist, buserelin, after oocyte recovery until the onset of vaginal bleeding. Frozen embryo replacement occurred in a hormone replacement cycle that started either on day 3 of the withdrawal bleed (group I;N=15) or after serum estradiol levels had fallen to <100 pmol/L (group II;N=16). The other patients commenced a frozen embryo replacement cycle several months later in either a hormone replacement (group III;N=15) or a natural (group IV;N=16) cycle. Results: Two patients developed severe ovarian hyperstimulation syndrome. There were no significant differences among the four groups regarding demographic variables, the dose of hMG used, and the clinical outcome. There was a higher but not significantly different clinical pregnancy rate in group I (26.7%), compared to group II (12.5%), group III (13.3%), and group IV (18.8%). Conclusions: Several options exist for the timing and protocol used for frozen embryo replacement in patients who had elective cryopreservation for the prevention of ovarian hyperstimulation syndrome, none of which was found to be clearly superior in this observational report.Presented at the 1994 Annual Conference of the American Fertility Society.  相似文献   
115.
原发性肝癌栓塞化疗后血清AFP浓度与疗效关系的探讨   总被引:3,自引:0,他引:3  
目的 :分析 5 5例原发性肝癌经肝动脉插管栓塞化疗 (Transcatheterhepaticarterialchemo -embolization ,TAE)后血清AFP浓度与疗效的关系。方法 :通过动脉插管和血管造影 ,采用不同的化疗药物对肿瘤组织进行局部注入。用放射免疫法测定AFP浓度。结果 :TAE后血清AFP浓度降低与疗效有关 ,AFP≥ 4 0 0ng dl组有效率为 12 % ,AFP <10 0ng dl组有效率为 85 7%(P <0 0 1) ;TAE治疗后血清AFP浓度仍大于 4 0 0ng dl组癌肿转移率明显高于AFP <10 0ng dl组 ,而 2年生存率明显低于AFP <10 0ng dl组 (P <0 0 5和P <0 0 1)。结论 :TAE后血清AFP浓度的检测可反映肝癌介入治疗后疗效、预后及生存率  相似文献   
116.
急性心肌梗死再灌注期间的心电变化特征   总被引:1,自引:1,他引:0  
目的 探讨急性心肌梗死 (AMI)再灌注期间的心电变化特征。方法  46例经急诊冠状动脉造影明确为成功再灌注的AMI,其中 2 4例接受溶栓治疗和 2 2例接受直接经皮腔内冠状动脉成形 ,于发病的 6小时内以动态心电图技术持续2 4小时监测心电图变化 ,并与 1 5例无灌注者进行对比。结果 ①再灌注发生后 ,相应导联ST段迅速下降 ,约 2小时达较低水平 ;同时 ,T波正向振幅进行性降低 ,距再灌注 0~ 2 2 (2 7± 4 5)小时呈现T波倒置并逐渐加深。②再灌注后的 1小时内 ,室性心律失常明显增加 ,6~ 8小时后显著减少。结论 AMI早期再灌注发生后呈现特征性心电变化 ,及时识别这些特征将有助于临床评估再灌注状态和危险度分层  相似文献   
117.
We present a patient with vertebrobasilar insufficiency, with vertigo and horizontal nystagmus, induced by turning the head to the right. Angiography demonstrated transient occlusion of the left vertebral artery at the atlantoaxial joint during rotation of the head. The pathogenesis and angiographic findings are discussed.  相似文献   
118.
A comparative non-randomized study was carried out to evaluate the role of systematic pelvic and para-aortic lymphadenectomy (SL) on patients with no residual intraperitoneal disease (NRID) of advanced ovarian cancer (stage IIIC–IV). A total of 142 optimally cytoreduced patients (macroscopic disease absent on peritoneal surface) were divided into two groups: Group A, consisting of 98 patients (53 previously untreated and 45 pretreated at other Institutions), who underwent SL; Group B, consisting of 44 patients (21 previously untreated and 23 pretreated at other Institutions), who did not undergo SL. Each group had statistically equivalent histology, grading, performance status and variety of cytoreductive operations performed. Group A pretreated patients had a greater number of stage III than Group B ( P  = 0.03). Systematic pelvic and para-aortic lymphadenectomy could be carried out with an acceptable morbidity and no mortality. All 142 patients received post-operative chemotherapy including carboplatin. The number of chemotherapy sessions did not differ between the two groups. Comparison of survival revealed that SL significantly improved the survival of previously untreated patients ( P  = 0.02). The survival was significantly different with nodal status ( P  = 0.006). Cox's proportional hazard analysis showed that only systematic lymphadenectomy was a significant covariate. The survival was not significantly different in Group A vs Group B pretreated patients; however, it was significantly different with respect to nodal status ( P <0.001). Cox's proportional hazard analysis showed that only the initial stage of disease was a significant covariate. The results of the present study shows that aggressive surgical cytoreduction with SL could be therapeutic in previously untreated patients with NRID. Currently, an international prospective randomized study is ongoing to clarify definitively the clinical role of SL.  相似文献   
119.
From May 1970 to September 1983, 1714 children with different forms of primary tuberculosis were referred to the paediatric home care centre (Enfants soignés au Foyer, E.S.F.) of the Brussels University Hospital St.-Pierre. They were subdivided in five groups: asymptomatic (33%), symptomatic (28%), dubious tuberculous infections (35%), high-risk contacts (3%) and unestablished diagnosis (1%). They were aged from 10 days to 19 years, and 82% of them were migrants of low socio-economic level. Fifty percent of the symptomatic infections, mainly pulmonary, appeared in children under 3 years of age. An adult source of contamination was identified in 33% of the case (48% of the symptomatic children). Diagnosis was based on tuberculin screening with a 2IU intradermal test. Gastric aspirates yieldedMycobacterium tuberculosis in 15% of our patients, 11% of them showing resistance to one or more tuberculostatic drugs. Treatment was given to 1359 patients with excellent results. Therapy was shortened during the last 2 years of the study from 12 to 6 months for the asymptomatic patients and from 12 to 9 months for the symptomatic infections. Few complications were observed. Tuberculosis remains a serious cause of morbidity particularly in migrant children. Correct diagnosis and treatment of the disease is very important.  相似文献   
120.
Data on the effects of laser radiation on primary teeth are scarce. This study investigates the effects of exposing sound enamel, photo-initiated sound enamel, sound dentine and carious dentine of extracted primary teeth to a pulsed neodymium-yttrium aluminium garnet laser (Nd-YAG, wavelength 1.06 μm, pulse length 15μs). Each type of tissue was exposed to three fiuences. Qualitative and quantitative assessments of the irradiated areas revealed that the most marked changes were produced in carious dentine, followed in ranking order by sound dentine, photo-initiated enamel and sound enamel. Evidence of thermal damage to the hard tissues peripheral to the fibre-optic tip, and considerable inter-sample variation were found. The experimental evidence obtained in this in vitro study does not support the clinical use of pulsed laser at 1.06 μm wavelength for cutting primary enamel and dentine.  相似文献   
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