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51.
52.
背景和目的:最近的研究结果表明,对其他一线药物和注射类药物(如卡那霉素、卷曲霉素)等耐药是影响耐多药结核病(MDR-TB)患者治疗效果的独立危险因素.本研究旨在明确耐其他一线药物和注射类药物对韩国不合并人免疫缺陷病毒(HIV)感染的MDR-TB患者临床疗效的影响.方法:采用回顾性队列研究分析1996年1月至2005年12月首尔国家大学附属医院治疗的211例MDR-TB患者治疗效果,排除7例丢失和7例迁出,对197例患者进行了最终分析.  相似文献   
53.
在2型糖尿病患者中,反映炎症和内皮功能障碍的生物标志已经与心血管疾病和代谢调节联系起来。二甲双胍和促胰岛素分泌剂被证明有相同的抗高血糖作用。此研究比较了二甲双胍和促胰岛素分泌剂瑞格列奈在非肥胖的2型糖尿病患者的心血管疾病生物标志上的效能。  相似文献   
54.
A baby with unilateral cleft lip, midline cleft palate and hypertelorism developed meningitis in the first 48 h of life. Examination of the nasopharynx showed a soft tissue mass, which was confirmed as a basal encephalocele by computed tomography. There was also congenital hydrocephalus and the corpus callosum was absent. Surgical treatment included repair of the anterior basal skull defect, repair of the lip and palate, and ventriculo-peritoneal shunt. There is currently evidence of developmental delay and right-sided visual impairment due to Morning Glory syndrome. This case demonstrates that basal encephalocele should be considered in any baby with midline facial deformity who develops meningitis.  相似文献   
55.
OBJECTIVE: The objective of this study was to retrospectively assess whether there was increased morbidity associated with the addition of selective pelvic and periaortic lymphadenectomy to hysterectomy in patients with endometrial carcinoma. STUDY DESIGN: From 1977 through 1988, 196 patients undergoing selective pelvic and periaortic lymphadenectomy plus hysterectomy were compared with 104 patients who underwent hysterectomy alone for endometrial adenocarcinoma. RESULTS: Only after adjusting for covariates was selective pelvic and periaortic lymphadenectomy associated with a higher estimated blood loss, which increased linearly with weight and was higher for black than for white women. The transfusion rate was similar for the two groups (selective pelvic and periaortic lymphadenectomy 6%, hysterectomy 10%). The mean blood loss was significantly different among the four gynecologic oncology surgeons (range 343 to 652 ml). The operating time primarily depended on patient weight and race, surgeon, and estimated blood loss. Postoperative hospital stay increased significantly with age, surgeon, wound infections, thrombotic events, and serious complications. Selective pelvic and periaortic lymphadenectomy had no effect on wound infections, which were directly related to operating time. Seventy-five (38%) of the selective pelvic and periaortic lymphadenectomy group and 19 (18%) of the hysterectomy group (p < 0.01) received whole-pelvic radiation with no difference in bowel complications (selective pelvic and periaortic lymphadenectomy 2/75, hysterectomy 1/19). The risk of serious complications was associated only with increasing age. CONCLUSION: Selective pelvic and periaortic lymphadenectomy in patients with endometrial carcinoma does not significantly add to morbidity from hysterectomy, which is related primarily to other factors such as patient weight, age, and race; operating time; and surgeon.  相似文献   
56.
One hundred 5- and 6-year-old children were studied with a contextual play technique in order to gain insight into their fears and worries. Sex differences and differences relating to questioning procedure were examined. The discussion included the potential usefulness of the method and some implications for parents and teachers.  相似文献   
57.
BACKGROUND:: Chronic oral administration of anticancer drugs may offer therapeuticadvantages. PATIENTS AND METHODS:: A total of 68 patients with advanced non-small-cell lung cancer,not previously treated by chemotherapy, were randomized to receiveeither ifosfamide given orally (OSI) at a dose of 1 g/day for14 days every 4 weeks, or as a 1-hour intravenous infusion (IVI)at a dose of 1.6 g/m2/day for 5 days every 4 weeks. Accordingto the route of ifosfamide administration, patients receivedeither mesna i.v. or mesna film-coated tablets for uroprotection. RESULTS:: Eight patients were found to be ineligible for the study andtherefore excluded for all analyses. Thirty-three patients receivedIVI, and 27 patients OSI. One patient randomized to OSI diedbefore treatment was initiated, leaving 59 patients fully evaluablefor toxicity. Hematological toxicity was less severe for patientson OSI, but CNS toxicity was reported more frequently on OSI(39%; 12% grade III/IV), than on 1VI (15%; 9% grade III/IV),which caused the premature close of the study. Other non-hematologicaladverse events were of modest clinical significance and comparablein both arms. Forty-nine patients were considered evaluablefor response: in the IVI arm, 5 (17%) of the 29 evaluable patientsobtained a partial remission, and 7 patients a no change (24%).In the OSI arm, 2 (10%) of the 20 evaluable patients obtaineda partial remission, and 11(52%) a stable disease. CONCLUSION:: Both arms have some activity in non-small-cell lung cancer;while OSI was less myelosuppressive than IVI, it was associatedwith a higher incidence of CNS toxicity. Oral administrationof ifosfamide, in the schedule and daily dose tested here cannotbe recommended. chemotherapy, ifosfamide, non-small-cell lung cancer, phase II trial  相似文献   
58.
Carcinogenic tobacco-specific nitrosamines are present in tobacco products and are believed to play a significant role in human cancers associated with tobacco use. Additional amounts of tobacco-specific nitrosamines could be formed endogenously. We tested this hypothesis by treating rats with nicotine and sodium nitrite and analyzing their urine. Initially, we treated groups of rats with (S)-nicotine (60 micromol/kg) and NaNO2 (180 micromol/kg), (S)-nicotine alone, NaNO2 alone or 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, 12 nmol/kg) by gavage twice daily for 4 days. We collected urine and analyzed for two metabolites of NNK; 4-(methylnitrosamino)-1-(3- pyridyl)-1-butanol and its glucuronide. We did not detect these metabolites in the urine of rats treated with nicotine alone or nicotine plus NaNO2, indicating that endogenous conversion of nicotine to NNK did not occur. However, the urine did contain N'- nitrosonornicotine (NNN), N'-nitrosoanabasine (NAB) and N'- nitrosoanatabine (NAT). Analysis of the (S)-nicotine used in this experiment demonstrated that it contained trace amounts of nornicotine, anabasine and anatabine. In a second experiment, we used an identical protocol to compare the endogenous nitrosation of this (S)-nicotine with that of synthetic (R,S)-nicotine, which did not contain detectable amounts of nornicotine, anabasine or anatabine. NNN (0.53 x 10(-3)% of nicotine dose), NAB (0.68%) and NAT (2.1%) were detected in the urine of the rats treated with the (S)-nicotine and NaNO2. NNN (0.47 x 10(- 3)% of dose), but not NAB or NAT, was present in the urine of the rats treated with synthetic (R,S)-nicotine and NaNO2. NNN probably formed via nitrosation of metabolically formed nornicotine. These results demonstrate for the first time that endogenous formation of tobacco- specific nitrosamines occurs in rats treated with tobacco alkaloids and NaNO2. The potential significance of the results with respect to nitrosamine formation in people who use tobacco products or nicotine replacement therapy is discussed.   相似文献   
59.
The present study investigated the expression and distribution of three isoforms of nitric oxide synthase (NOS) in different anatomical regions of the human stomach and in gastric neoplastic tissues by immunohistochemistry using specific antibodies. Intracellular localization of individual isoenzymes of NOS was detected in normal gastric mucosa. Gastric cancer tissues had a marked reduction of all three NOS isoforms expression. The expression of the endothelial NOS, neuronal NOS and inducible NOS in the tumor tissue was significantly lower than in normal gastric mucosa (P = 0.01, P = 0.02, P < 0.01, respectively). In the tumor tissue the expression of inducible NOS was significantly lower than the expression of both constitutive forms of NOS (P < 0.01). There was a tendency to higher expression of both constitutive forms of NOS in earlier stages T2 of the tumor compared to advanced T4 tumor. In contrast, the expression of inducible NOS was higher than in the advanced T4 tumor than in the earlier stages T2 of the tumor. The mapping of the expression of endothelial NOS, neuronal NOS and inducible NOS in human stomach showed higher expression of NOS isoforms in the distal third than in the proximal third of the stomach (P = 0.03, P = 0.04, P = 0.01, respectively). We conclude that there is greater expression of NOS in the stomach corpus and in antrum than in the proximal third of the normal human stomach mirroring the anatomical predilection of common pathological changes in this part of the human stomach. Furthermore, there was loss of the expression of individual isoenzymes in gastric neoplasms.   相似文献   
60.
Hecht  SS; Spratt  TE; Trushin  N 《Carcinogenesis》1997,18(9):1851-1854
4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) is an important metabolite of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1- (3-pyridyl)-1-butanone (NNK). Using the chiral derivatizing agent, (R)- (+)-alpha-methylbenzyl isocyanate [(R)-(+)-MBIC], previous work has shown that the enantiomeric ratio of metabolically formed NNAL and its glucuronide derivative may be species dependent. However, the absolute configuration of such NNAL has not been previously reported. Synthetically prepared racemic NNAL was converted to diastereomeric esters by reaction with (R)-(+)- and (S)-(-)-alpha-methoxy-alpha- (trifluoromethyl)phenylacetic acid (MTPA) chloride (Mosher's reagent) and the products were characterized by 1H-NMR. Based on chemical shift data, the absolute configuration of NNAL in each diastereomeric ester was assigned. Hydrolysis of (R)-NNAL-(R)-MTPA gave (R)-NNAL. This was converted to the corresponding carbamate by reaction with (R)-(+)-alpha- MBIC and the absolute configurations of the diastereomeric carbamates formed by reaction of (R)- and (S)-NNAL with (R)-(+)-MBIC were thereby assigned. Conversion of metabolically produced NNAL to the same carbamates allowed us to assign the NNAL formed from NNK by rat liver microsomes as (R)-NNAL. The major and minor NNAL-glucuronide diastereomers found in the urine of patas monkeys and humans exposed to NNK were similarly assigned; they were formed from (R)-NNAL and (S)- NNAL, respectively.   相似文献   
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