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991.
用血清学方法对胃癌高发区兰州地区3781名各年龄组健康人群进行前瞻性幽门螺杆菌(Helicobacterpylori,HP)感染调查,并与胃癌低发区广州地区的资料进行比较。结果显示:兰州地区HP总感染标化率为61.6%,高于广州地区的48.3%(P<0.001)。两者之间的差异在10岁以下儿童,尤其是4岁以下幼儿最显著(分别为43.2%与19.3%,P<0.001);兰州地区HP阳性率的高峰年龄段在30~39岁,比广州地区提早10年以上出现,可能与胃癌高发区人群较早出现HP相关性萎缩性胃炎及肠上皮化生有关。  相似文献   
992.
993.
Continuous wave Doppler ultrasound was used together with B-mode real time ultrasound to study feto-placental blood flow in utero. The results of 887 examinations on 221 patients are presented. The fetal heart rate acceleration slope and pulsatility index (P.I.) of the audiofrequency ultrasound display were analysed. There was a significant reduction in fetal heart rate (P less than 0.001) and P.I. (P less than 0.001) with advancing gestational age in normal pregnancy. In contrast, in retarded intrauterine growth a significant increase in P.I. values was observed in 77% of patients.  相似文献   
994.
P Paredi  S Loukides  S Ward  D Cramer  M Spicer  S Kharitonov    P Barnes 《Thorax》1998,53(9):775-779
BACKGROUND: Expiratory flow rate, soft palate closure, and dead space air may influence exhaled levels of nitric oxide (NO). These factors have not been evaluated in the reservoir collection of NO. METHODS: Exhaled NO was collected into a reservoir during a single flow and pressure controlled exhalation. RESULTS: NO collected in a reservoir containing silica gel was stable for 24 hours. Nasally delivered 4.8% argon measured by mass spectrometry did not contaminate exhaled argon levels (0.1 (0.02)%) in five volunteers during exhalation against a resistance (10 (0.5) cmH2O), hence proving an effective soft palate closure. Exhaled NO in the reservoir was 11 (0.2) ppb, 8.6 (0.1) ppb, 7.1 (0.6) ppb, and 6.6 (0.4) ppb in five normal subjects and 48.3 (18) ppb, 20.3 (12) ppb, 16.9 (0.3) ppb and 10.1 (0.4) ppb in 10 asthmatic subjects at four studied expiratory flows (5-6, 7-8, 10-11, and 12-13 l/min, respectively), with NO levels equal to direct measurement (7.3 (0.5) ppb and 17.4 (0.5) ppb for normal and asthmatic subjects respectively, p < 0.05) at the flow rate 10-11 l/min. Elimination of dead space proved necessary to provide NO levels comparable to the direct measurement. Exhaled NO collected into the reservoir without dead space during flow controlled exhalation against mild resistance provided close agreement (mean (SD) difference -0.21 (0.68), coefficient of variation 4.58%) with direct measurement in 74 patients (NO range 1-69 ppb). CONCLUSIONS: Flow and pressure controlled collection of exhaled NO into a reservoir with silica gel provides values identical to the direct measurement and may be used to monitor asthma at home and where analysers are not on site.  相似文献   
995.
In mice, only makes are susceptible to chloroform (CHCl3) nephrotoxicity and the susceptibility appears to be related to renal mixed function oxidase activity. There were sex-related differences of renal cytochrome P-450 and b5 concentrations and of ethoxycoumarin O-deethylase activity in mouse kidneys; in all cases activity was higher in males. Castration of male mice eliminated susceptibility to ChCl3 nephrotoxicity and reduced renal mixed function oxidases to concentrations observed in female mice. Treatment of male and female mice with testosterone increased the susceptibility to ChCl3 nephrotoxicity and increased renal mixed function oxidases to similar activities in both sexes. Previous data have suggested that CHCl3 is metabolized in situ by the kidney, possibly by a mechanism similar to that occurring in the liver. The data from this investigation are consistent with the concept that CHCl3 is metabolized by a cytochrome P-450-dependent mechanism in the kidney.  相似文献   
996.
We report a case of delayed closed rupture of the tendon of extensor indicis proprius in a skeletally immature individual. This occurred following a minor greenstick fracture during use of a gymnast's wrist-finger support. To our knowledge this unusual complication has not been described previously.  相似文献   
997.
998.
The difficulties encountered in producing highly specific antisera to human chorionic gonadotrophin (hCG) were overcome by the use of hybridoma technology. A panel of monoclonal antibodies directed toward hCG and its subunits was produced. Of the four antibodies which were fully characterized, one recognized the intact hCG molecule only, a second recognized only the free beta-subunit, a third recognized only the free alpha-subunit and the fourth bound to the beta-subunit of hCG both when it was in the free form and when it was associated with the alpha-subunit forming the intact hCG molecule. There was no significant cross-reaction of any of these antibodies with the pituitary glycoprotein hormones. The four antibodies had high binding affinities which should permit their use in immunoassays for measurement of circulating levels of hCG and its subunits.  相似文献   
999.
A patient with a malignant thymoma developed systemic lupus erythematosus with neurological involvement and multiple infectious complications, including progressive multifocal leukoencephalopathy and cryptococcal meningitis. Data from this patient and studies by others are consistent with the concept that all cases of progressive multifocal leukoencephalopathy are associated with a defect in cellular immunity.  相似文献   
1000.
To determine what physiologic changes might contribute to the development of the postthrombotic syndrome, venous outflow, venous refilling time, and valvular competence were assessed in 32 patients (39 limbs) with documented deep venous thrombosis. The follow-up ranged from nine to 144 months (mean, 41 months) after the acute deep venous thrombosis. Pain was noted by 49% of the patients, but more objective end points occurred less frequently (edema, 21%; pigmentation, 26%; ulceration, 3%). Venous outflow was lower in the affected limbs but was not a good indicator of those patients with or without symptoms. Venous refilling time after calf compression was markedly reduced in limbs with incompetent valves (mean +/- SD, 8.4 +/- 3.8 s v 25.3 +/- 12.1 s), as well as in those with edema, pigmentation, and ulceration. It appears that most of the sequelae of the postthrombotic syndrome can be attributed to the loss of valvular function.  相似文献   
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