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81.
Bronchopulmonary sequestration is an uncommon pulmonary disorder characterized by an area of non‐functioning abnormal lung tissue, which receives its blood supply from a systemic artery and characteristically has no connection with the tracheobronchial tree. The abnormal lung tissue is located within the visceral pleura of a pulmonary lobe in the intralobar variety, whereas the extralobar form has its own visceral pleura. The venous drainage of the extralobar type is usually into the systemic veins, whereas the intralobar type drains into the pulmonary veins. Radiological imaging plays a vital role in establishing the diagnosis, and even more importantly, in providing to the clinician a vascular roadmap essential for surgical planning. We present here a review of bronchopulmonary sequestration and also discuss the role of various imaging methods in the early diagnosis and management of these cases.  相似文献   
82.
HPLC分离测定格列齐特片及其有关物质   总被引:6,自引:0,他引:6  
目的:建立新的HPLC法分离测定格列齐特征及其有关物质。方法:色谱条件为:Shim-Pack VP-ODS(5um,150mm*4.6mm i.d.)色谱柱;甲醇-0.02mol/L磷酸(用三乙胺调节PH至3.5),(70:30)为流动相;检测波长为229nm。结果:在50-300ug;/ml的浓度范围内线性关系良好。r=0.9999(n=6);平均回收率为100.5%,RSD为0.17%(n=6),重复进样RSD为0.12%(n=6),格列齐特及其有关物质得到基线分离。结论:本法简便,快速,准确,适用于格列齐特及其制剂的质量控制。  相似文献   
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Rosenbaum  RC; Johnston  GS 《Radiology》1986,160(1):91-94
The authors studied 54 patients with multisystem trauma, including blunt chest injury, using combined dynamic first-pass and electrocardiographically (ECG) gated radionuclide ventriculography (RNV) to evaluate for posttraumatic myocardial dysfunction. Twenty-six of 54 (48%) patients had abnormalities of ventricular wall motion. The ventricular dysfunction was confined to the right ventricle in 92% of cases. In general, abnormalities consisted of right ventricular dilatation and diffuse hypokinesia, although in seven cases there were localized wall-motion abnormalities. The right ventricular ejection fraction of those patients with wall-motion abnormalities was significantly lower than those with normal studies. Left ventricular ejection fraction did not differ significantly between these groups. ECG changes were not associated with the cardiac dysfunction demonstrated scintigraphically, nor was there a relationship between the number or type of extrathoracic or thoracic injuries demonstrated by RNV. Follow-up studies obtained in 15 cases showed a significant overall improvement in cardiac function by 3 weeks after injury. Combined first-pass and ECG-gated RNV is useful for the identification and follow-up of patients with posttraumatic cardiac dysfunction.  相似文献   
85.
86.
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG repeat expansion in the first exon of the androgen receptor (AR) gene. Disease-associated alleles (37-66 CAGs) change in length when transmitted from parents to offspring, with a significantly greater tendency to shift size when inherited paternally. As transgenic mice carrying human AR cDNAs with 45 and 66 CAG repeats do not display repeat instability, we attempted to model trinucleotide repeat instability by generating transgenic mice with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions in their genomic context. Studies of independent lines of AR YAC transgenic mice with CAG 45 alleles reveal intergenerational instability at an overall rate of approximately 10%. We also find that the 45 CAG repeat tracts are significantly more unstable with maternal transmission and as the transmitting mother ages. Of all the CAG/CTG repeat transgenic mice produced to date the AR YAC CAG 45 mice are unstable with the smallest trinucleotide repeat mutations, suggesting that the length threshold for repeat instability in the mouse may be lowered by including the appropriate flanking human DNA sequences. By sequence-tagged site content analysis and long range mapping we determined that one unstable transgenic line has integrated an approximately 70 kb segment of the AR locus due to fragmentation of the AR YAC. Identification of the cis - acting elements that permit CAG tract instability and the trans -acting factors that modulate repeat instability in the AR YAC CAG 45 mice may provide insights into the molecular basis of trinucleotide repeat instability in humans.   相似文献   
87.
88.
A correct diagnosis and an understanding of the aetiology and dynamics of the processes involved in tooth resorption is critical to effective management. Tooth resorptions can be classified as: (1) trauma induced; (2) infection induced; or (3) hyperplastic invasive. Some transient trauma induced resorptions require no treatment but must be carefully monitored to check that there are no complicating issues such as infection. In cases of trauma induced replacement resorption, a multidisciplinary approach is usually necessary to ensure an optimal long-term solution. Infection induced tooth resorptions require the removal of the invading micro-organisms by endodontic therapy including intra-canal medication which can also facilitate repair of the resorbed tooth structure. The hyperplastic invasive tooth resorptions pose considerable challenges in management due to the complexity and aggressive nature of the resorptive process. With careful case selection and complete inactivation of resorptive tissue successful management can be achieved.  相似文献   
89.
The serotonin (5HT3) antagonist ondansetron was compared in a randomised study with metoclopramide and dexamethasone for the prevention of chemotherapy induced emesis. Thirty children aged 1-15 years with acute lymphoblastic leukaemia received 'intensification modules' according to the MRC United Kingdom acute lymphoblastic leukaemia regimen UKALL XI. This contains the moderately emetogenic drugs daunorubicin, etoposide, and cytarabine. Fifteen children received an intravenous loading dose of ondansetron followed by intravenous or oral doses 12 hourly for five days. Fifteen children received intravenous metoclopramide every six hours for three days with a loading dose of dexamethasone, repeated every eight hours for three days intravenously or orally. Efficacy was assessed by a diary card documenting the incidence of nausea, retching, or vomiting. In the 24 hour period after starting chemotherapy, ondansetron was more effective, with a complete or major response rate of 93%, compared with 33% using metoclopramide/dexamethasone.  相似文献   
90.
争光霉素A6和它在争光霉素复合物的地位   总被引:8,自引:0,他引:8  
争光霉素A5已鉴别为Bleomycin A6,在争光霉素复合物中所占比例一般在10%左右,在某些批样中可高达15%以上。文献报告Bleomycin A6在天然产的Bleomyein复合物中只有痕量。通过向发酵培养基中加入特定组分的末端胺可大大提高其特定组分在复合物中的含量比而其它组分的产生则不同程度地被抑制。但Bleomyein A6例外,即使向培养基中加入其末端胺精胺(0.3mg/ml),在所产生的复合物中大大增多的组分是Bleomyein A6,而Bleomycin A6仍只有痕量。这表明争光霉素产生菌有和Bleomycin产生菌明显不同的特点。  相似文献   
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