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21.
Quantitative ultrasound (QUS) is emerging as a simple, inexpensive and noninvasive method for assessing bone quality and assessing fracture risk. We assessed the usefulness of a contact calcaneal ultrasonometer by studying normal premenopausal women (group I, n= 53), normal postmenopausal women (group II, n= 198), and osteoporotic women without (group III, n= 141) and with vertebral fractures (group IV, n= 53). The osteoporotic subjects had a T-score of the spine or hip neck bone mineral density (BMD) <−2.5 based on the local Chinese peak young mean values. When compared with postmenopausal controls, mean broadband ultrasound attenuation (BUA), speed of sound (SOS), and quantitative ultrasound index (QUI) were 26%, 2.1% and 25% lower in women with vertebral fractures (p all <0.005). The correlation coefficients between QUS parameters and BMD of the spine and hip ranged between 0.4 and 0.5. The ability of the QUS to discriminate between patients groups was determined based on the mean value of normal premenopausal women in group I. The mean T-score for women with fractures was −2.87 ± 1.02 for BUA, −2.54 ± 0.79 for SOS, −3.17 ± 0.70 for QUI, −2.65 ± 0.86 for L2–4 BMD and −2.53 ± 0.66 for hip neck BMD. After adjustment for age and body mass index, the odds ratio of vertebral fracture was 1.71 (95% CI 1.2–2.6) for each 1 SD reduction in BUA, 2.72 (1.3–5.3) for SOS, 2.58 (1.4–4.6) for QUI, 2.33 (1.6–3.3) for L2–4 BMD, 2.09 (1.37–3.20) for femoral neck BMD and 1.88 (1.34–2.92) for total hip BMD. The association between the QUS parameters and vertebral fracture risk persisted even adjustment for BMD. The area under the receiver operating characteristic curve for BUA for vertebral fracture was 0.92, for SOS, QUI, L2–4 BMD and femoral neck BMD was 0.95, and for total hip was 0.91. Received: 7 January 1999 / Accepted: 18 May 1999  相似文献   
22.
Onconase, a ribonuclease isolated from Rana pipiens oocytes and early embryos, is a member of the RNase A superfamily. Onconase has anti-neoplastic properties both in vitro and in vivo, and is undergoing clinical evaluation. In the present study, Onconase was combined with or conjugated to MRK16, an anti-P-glycoprotein (Pgp) monoclonal antibody. The interaction of these combinations with vincristine (VCR) against parental and multidrug resistant (MDR), Pgp expressing, human colon carcinoma cells caused increased VCR cytotoxicity in vitro and enhanced survival of athymic nude mice given transplants of drug resistant HT-29(mdr1) cells in vivo. The results suggest that combination treatment with Onconase and other agents that modulate the chemosensitivity of Pgp-expressing human tumor cells has the potential to overcome MDR.  相似文献   
23.
254例肾细胞癌的诊治及预后   总被引:2,自引:1,他引:2  
燕翔  方祖军  郑捷  杨醌  李强  张佐良  陈波  姚孟树  丁强  张元芳 《肿瘤》2004,24(3):248-250
目的探讨肾癌的临床诊治方法及预后.方法对本院1993年1月~2001年12月收治的254例肾癌临床资料进行回顾性分析及随访.结果典型肾癌“三联征”的发生率为2.4%;肾癌偶发癌占45.7%.“肾外表现”主要有:贫血40.9%,消瘦14.6%,发热12.6%,高血压10.2%.病程<3个月占73.6%(187/254).辅助检查以B超、CT为主.治疗以肾癌根治术为主,占87.4%,术后结合干扰素治疗,效果确切.术后3年、5年生存率分别为78.7%、72.9%.预后多因素分析结果表明,肾癌的预后与肿瘤分期、直径大小和C-erbB2阳性与否相关.结论临床上无任何表现而体检偶发的肾癌日渐增多,典型的肾癌“三联征”已少见.综合分析患者的病史、体检,结合辅助检查,有助于肾癌的早期诊断,适当条件下的健康体检有积极意义.治疗仍以肾癌根治术为主,术后免疫治疗有积极的意义.肿瘤分期、直径大小和C-erbB2阳性与否对肾癌的预后有提示作用.  相似文献   
24.
25.
Objective: To compare the pregnancy rates, between intrauterine insemination (IUI) followed by timed intercourse and IUI only for treatment of the infertile couples. Study design: A prospective study of two different protocols of intrauterine insemination in two hundred and one infertile couples with a normal spermiogram was carried out. Of these, 101 couples were treated with IUI alone and 100 couples had both IUI and timed intercourse within a 12-18 h period. The pregnancy rates were compared between groups. Results: The characteristics of the two groups were similar in terms of the mean age, as well as the duration and causes of infertility. The cycle characteristics following follicular stimulation were also similar between two groups. The pregnancy rate per cycle increased with increasing numbers of total motile sperm per insemination in the IUI alone group (P=0.045). Timed intercourse increased pregnancy rate in patients with lower motile sperm number (<40×106) (27.7% versus 10.5%, P=0.023), but not in patients with higher sperm number (≥40×106) (25.7% versus 22.7%, P=0.671). Conclusions: In IUI with low number of motile sperm inseminated, timed intercourse significantly increases the pregnancy rates over IUI alone in infertile couples with a normal sperminogram. This alternative treatment appears to be a practical, simple, and inexpensive addition that improves the pregnancy rate in patients receiving ovulation induction and intrauterine insemination program.  相似文献   
26.
Involvement of the dopaminergic system has been suggested in patients suffering from attention deficit hyperactivity disorder (ADHD) since the symptoms can be successfully treated with methylphenidate, a potent blocker of the dopamine transporter (DAT). This study reports the findings on the status of the DAT in adults with ADHD before and after commencement of treatment with methylphenidate, as measured using [99mTc]TRODAT-1. Seventeen patients (seven males, ten females, aged 21-64 years, mean 38 years) were examined before and after the initiation of methylphenidate treatment (3x5 mg/day). All subjects were injected with 800 MBq [99mTc]TRODAT-1 and imaged 3 h p.i. Single-photon emission tomography (SPET) scans were acquired using a triple-headed gamma camera. For semiquantitative evaluation of the DAT, transverse slices corrected for attenuation were used to calculate specific binding in the striatum, with the cerebellum used as background [(STR-BKG)/BKG]. Data were compared with an age-matched control group. It was found that untreated patients presented with a significantly increased specific binding of [99mTc]TRODAT-1 to the DAT as compared with normal controls [(STR-BKG)/BKG: 1.43+/-0.18 vs 1.22+/-0.06, P<0.001]. Under treatment with methylphenidate, specific binding decreased significantly in all patients [(STR-BKG)/BKG: 1.00+/-0.14, P<0.001]. Our findings suggest that the number of DAT binding sites is higher in drug-naive patients suffering from ADHD than in normal controls. The decrease in available DAT binding sites under treatment with methylphenidate correlates well with the improvement in clinical symptoms. The data of this study help to elucidate the complex dysregulation of the dopaminergic neurotransmitter system in patients suffering from ADHD and the effect of treatment with psychoactive drugs.  相似文献   
27.
28.
Influenza vaccination is recommended for all health care personnel (HCP), but immunization rates for this group continue to be suboptimal. This study explores relationships between individual characteristics, beliefs, knowledge, attitudes, and vaccination behavior through 2 surveys conducted at a university health center. The findings suggest that HCP who were vaccinated the year before, intended to be vaccinated next year, believed influenza vaccination was important, and were more knowledgeable are more likely to receive a vaccine.  相似文献   
29.
Urinary retention is a common complication among patients after haemorrhoidectomy. Although Crede's method is recommended for urinary retention in nursing practice textbooks, its effects require further examination. The purpose of this study was to investigate the rate of urine voiding within the first 8 h following haemorrhoidectomy and to examine the effects of Crede's method on this postoperative outcome. A two‐group comparison study was conducted. All participants were over 20 years of age, and each had undergone haemorrhoidectomy. Outcome measurements included patients' self‐reported urine voiding within 8 h of surgery, personal demographics and disease‐related data. Before the surgical procedure, participants were divided into Crede's group and non‐Crede's group, and written educational materials were given. Patients in the Crede's group were taught Crede's method for application in the event that they were unable to void urine after haemorrhoidectomy. The non‐Crede's group patients were taught traditional methods without Crede's method. We examined urine voiding within the first 8 h after haemorrhoidectomy. The mean rate of urine voiding within 8 h of surgery was 60·9% overall, with 91·3% (21/23) in the Crede's group and 30·4% (7/23) in the non‐Crede's group reporting successful voiding. After controlling for the two groups' personal characteristics and disease‐related variables, age, educational level and perioperative fluid administration were treated as covariates and included in the multinomial logistic regression model. The odds ratio of urine voiding within the first 8 h after surgery was 52·70‐fold higher in the Crede's group than in the non‐Crede's group (p < 0·01). This study shows that Crede's method is an effective strategy to aid in urine voiding within the first eight postsurgical hours among patients following haemorrhoidectomy. Clear and concise information about urinary retention and related management strategies should be given to patients before haemorrhoidectomy.  相似文献   
30.
Intraoperative intracranial pressure (ICP) and cerebral perfusion pressure (CPP) were evaluated for use as prognostic indicators after surgery for severe traumatic brain injury (TBI), and threshold ICP and CPP values were determined to provide guidelines for patient management. This retrospective study reviewed data for 66 patients (20 females and 46 males) aged 13–83 years (average age, 48 years) who had received decompressive craniectomy and hematoma evacuation for severe TBI. The analysis of clinical characteristics included Glascow Coma Scale score, trauma mechanism, trauma severity, cerebral hemorrhage type, hematoma thickness observed on computed tomography scan, Glasgow Outcome Scale score, and mortality. Patients whose treatment included ICP monitoring had significantly better prognosis (p < 0.001) and significantly lower mortality (p = 0.016) compared to those who did not receive ICP monitoring. At all three major steps of the procedure, i.e., creation of the burr hole, evacuation of the hematoma, and closing of the wound, intraoperative ICP and CPP values significantly differed. The ICP and CPP values were also significantly associated with surgical outcome in the severe TBI patients. Between hematoma evacuation and wound closure, ICP and CPP values differed by 6.8 ± 4.5 and 6.5 ± 4.6 mmHg, respectively (mean difference, 6 mmHg). Intraoperative thresholds were 14 mmHg for ICP and 56mmH for CPP. Monitoring ICP and CPP during surgery improves management of severe TBI patients and provides an early prognostic indicator. During surgery for severe TBI, early detection of increased ICP is also crucial for enabling sufficiently early treatment to improve surgical outcome. However, further study is needed to determine the optimal intraoperative ICP and CPP thresholds before their use as subjective guidelines for managing severe TBI patients.  相似文献   
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