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121.
The objective of this study was to determine whether the proposed Malan radiological sinusitis typing (RST) system facilitated a level of agreement and ease of use comparable with the Lund–Mackay (LM) system for chronic rhinosinusitis. Ten observers (one otolaryngologist and nine radiologists), in two separate centres (regional and tertiary), blinded to all clinical data, used these two systems to independently and randomly score and type 15 sets of scans, recording the time to score each film. Using unweighted kappa scores, both methods facilitated a moderate level of agreement, slightly better with the LM system. The Malan system is more time efficient. Preliminarily, this study shows that the Malan RST system is easy to apply with a comparable level of agreement. The Malan RST system is a focused attempt at classifying disease extent radiologically and correlating it to a surgical approach. It emphasizes that scoring systems are vulnerable and proves to be superior to the LM system as a surgical planning tool. To score sinus disease, a Quality‐of‐Life questionnaire in association with this typing method is more appropriate. 相似文献
122.
王妍 《中国实用乡村医生杂志》2007,14(7):47-49
亚临床甲状腺功能亢进和甲状腺功能减退属于试验诊断。2002年美国甲状腺协会、美国临床内分泌医师协会和内分泌腺协会的委员组成的一个专家小组,明确了亚临床甲状腺疾病的概念,回顾了涉及风险和治疗益处的文献,并且建议进行评估和人口筛查。 相似文献
123.
124.
S.K. MITCHELL L.F. CARSON P. JUDSON & L.S. DOWNS JR 《International journal of gynecological cancer》2005,15(5):793-798
Topotecan (1.5 mg/m(2)/day for 5 consecutive days of a 21-day cycle) is an established recurrent ovarian cancer treatment, but myelosuppression can be dose limiting. This study evaluates the activity and tolerability of low-dose topotecan in our clinical experience. Case records were reviewed for patients with recurrent ovarian cancer in first through third relapse. Eligible patients had received > or =2 cycles of < or =1.25 mg/m(2) topotecan. Adverse events were evaluated using laboratory and clinical evaluation data. Twenty-seven eligible patients, most with advanced disease, received a total of 209 cycles (median, six cycles). Grade 3 or 4 hematologic toxicities during 184 cycles in 24 assessed patients were neutropenia, leukopenia, thrombocytopenia, and anemia in 35%, 28%, 36%, and 11% of cycles, and 21, 19, 16, and 10 patients, respectively. Only four grade 4 toxicities occurred: anemia (one) and thrombocytopenia (three). Myelosuppression was reversible, noncumulative, and manageable. Moreover, nonhematologic toxicity was generally mild to moderate, and the only two grade 3 events were constipation and deep vein thrombosis. Low-dose topotecan was active in this setting. Lower-dose topotecan is generally well tolerated and active in patients with pretreated ovarian cancer. Prospective clinical trials of low-dose topotecan in recurrent ovarian cancer are warranted. 相似文献
125.
Shapiro WR Shapiro JR 《中国神经肿瘤杂志》2006,(4)
The past 30 years have witnessed a major paradigm shift in brain tumor research with the development of a wide variety of molecular 相似文献
126.
JR Bapuraj V Ojili SK Singh GRV Prasad N Khandelwal S Suri 《Journal of Medical Imaging and Radiation Oncology》2006,50(2):179-182
Leiomyoma of the vagina is a very rare tumour of the lower urogenital tract. These slow‐growing masses may be asymptomatic or present with pain, dyspareunia or urinary symptoms. Rarely, these tumours may present with life‐threatening haemorrhage. These hypervascular tumours are treated by surgical excision. Preoperative embolization therefore may aid in devascularization of these tumours before surgical excision. We present the MRI features of a case of vaginal leiomyoma, which was managed by preoperative embolization and was then excised in toto. To the best of our knowledge, this is the first report where preoperative embolization was performed before excision of a vaginal leiomyoma with minimal peroperative blood loss. 相似文献
127.
128.
目的探讨单核细胞向巨噬细胞分化过程中CD44 mRNA表达和黏附功能的变化。方法应用豆蔻佛波醇乙酯(PMA)诱导单核细胞系U937向巨噬细胞分化;应用RT-PCR分析U937细胞CD44 mRNA表达变化,并以β-actin作为内参进行半定量评价,并对主要条带进行测序;应用荧光染料BCECF/AM作为探针,测定黏附于激活的内皮细胞上的U937细胞数目。结果与对照组比较,PMA诱导的U937细胞CD44 mRNA总体表达显著增加(P=0.01037),异构体/标准CD44比例显著上升(P=0.0005551),测序结果显示PMA刺激后显著增加的是947 bp(V8 V9 V10)和1208 bp(V7 V8 V9 V10)CD44异构体。同时,PMA刺激后U937细胞黏附功能显著增加(P=0.0029)。结论单核细胞向巨噬细胞分化过程中CD44 mRNA,特别是947bp(V8 V9 V10)和1208 bp(V7 V8 V9 V10)CD44异构体的表达显著增加,可能与细胞黏附功能的增强相关。 相似文献
129.
Benzo[a]pyrene at an environmentally relevant dose is slowly absorbed by, and extensively metabolized in, tracheal epithelium 总被引:2,自引:0,他引:2
Gerde P; Muggenburg BA; Thornton-Manning JR; Lewis JL; Pyon KH; Dahl AR 《Carcinogenesis》1997,18(9):1825-1832
While tobacco smoke has been conclusively identified as a lung carcinogen,
there is much debate over which smoke constituent(s) are primarily
responsible for its carcinogenicity. Previous studies in our laboratory
suggested that highly lipophilic carcinogens are slowly absorbed in the
thicker epithelium of the conducting airways, potentially allowing for
substantial local metabolism. The bioactivation of polycyclic aromatic
hydrocarbons in airway epithelium may, hence, be important in tobacco
smoke-induced carcinogenesis. In the present study, the hypothesis of slow
absorption and substantial local metabolic activation of highly lipophilic
carcinogen in airway epithelium was tested in dogs. A single dose of
tritiated benzo[a]pyrene (BaP) dissolved in a saline/phospholipid
suspension was instilled in the trachea, just anterior to the carina. At
intervals of a few minutes up to 30 min over a 3-h period, blood samples
were drawn from the azygous vein, which drains the area around the point of
instillation, and from the systemic circulation. Tissue samples were taken
at the end of the experiment. The concentration of BaP with depth into the
tracheal mucosa was determined with autoradiography. BaP was slowly
absorbed into the trachea with a half-time of approximately 73 min, which
is consistent with diffusion-limited passage through the epithelium and
lead to local doses in the tracheal epithelium that were more than a
1000-fold those of other tissues. The long retention of BaP in the
epithelium provided the local metabolizing enzymes with high substrate
levels over a long period, resulting in extensive metabolism. At 3 h after
the exposure, 23% of the BaP-equivalent activity remained in the tracheal
mucosa. Of this fraction, 13% was parent compound, 28% was organic
extractable, 31% was water-soluble, and 28-7% of the instilled dose was
bound to tracheal tissues. These results explain the tendency of highly
lipophilic carcinogens, such as BaP, to induce tumors at the site of entry
and, furthermore, indicate that the highly lipophilic components of tobacco
smoke and polluted air may be the most important contributors to lung
tumors of the conducting airways.
相似文献
130.
The present report describes psychobiological studies of behavior around the time of birth. An adaptive, ecological perspective is presented in which stimulation of the fetus and newborn is purported to instigate adaptive postpartum behavior. Studies describing the perinatal sensory environment are reviewed, with a consideration of emergent sensory function of the fetus. It is asserted that afferent input associated with parturition perturbs the fetus and neonate, producing a general arousal state that facilitates breathing, suckling, and early learning. The view developed herein is that perinatal sensory input induces and canalizes the newborn's behavior, thereby regulating adaptive postpartum function. Deviations in afferent input may alter ontogenetic trajectories and compromise developmental outcome by reducing availability of conditions necessary for adequate postpartum adaptation. 相似文献