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排序方式: 共有2211条查询结果,搜索用时 343 毫秒
281.
The adenoid tissue is an immunecompetent lymphoid organ, which has the capacity of reacting against numerous antigens. We have studied the influence that the elimination of the said tissue would have on the total IgE serum levels in 33 patients of an average age of 5 and criteria of adenoidectomy and in whom these levels were measured before and after surgery. We have not noticed any statistically significant differences in the IgE values after adenoidectomy with respect to those prior to surgery, which were normal. Adenoidectomy, like other authors have observed after tonsillectomy, does not alter the IgE serum values. 相似文献
282.
OA Sutochnikova MV Samsonova AV Cherniak AL Cherniaev AS Sokolov AG Chuchalin 《Canadian Metallurgical Quarterly》1996,68(3):48-50
11 patients with severe bronchial asthma entered a randomized trial of glucocorticosteroid budesonide of Russian produce. Of them 6 patients received inhalations of budesonide (800 micrograms/day for 6 months), 5 control patients did not receive the drug. As shown by investigations of external respiration and bronchoalveolar lavage with estimation of cytogram, metacholine provocative tests, fiber bronchoscopy, budesonide inhalations relieved clinical symptoms of asthma, bronchial hyperreactivity and inflammation. 相似文献
283.
JC van den Bos LJ Rijks PA van Doremalen K de Bruin AG Janssen EA van Royen 《Canadian Metallurgical Quarterly》1998,25(8):781-789
Five putative iodinated progesterone receptor (PR) binding ligands were synthesized and evaluated as potential imaging agents for PR-positive human breast tumours. Two compounds (E- and Z-17-hydroxy-21-iodo-19-nor-17alpha-pregna-4,20-dien-3-one; E- and Z-IPG1) were previously described, but are re-evaluated. The other three were novel compounds: two nortestosterone analogues derived from ORG 3236 (E- and Z-13-ethyl-17-hydroxy-21-iodo-11-methylene-18,19-dinor-17alpha-pre gna-4,20-diene-3-one; E- and Z-IPG2) and one norprogesterone analogue derived from ORG 2058 (21-[4-iodophenoxy]-16alpha-ethyl-19-norpregn-4-ene-3, 20-dione; IPG3). The E-iodovinyl nortestosterone compounds were obtained by a new route of synthesis. Competitive binding studies were performed to determine their binding affinities for the PR in three types of tissue (human MCF-7 breast tumour cells and rat uterine and mammary tumour tissue) and for the androgen receptor (AR) in human MCF-7 breast tumour cells, as well as for the sex hormone-binding globulin (SHBG) and corticosteroid-binding globulin (CBG) in human plasma. All four 17alpha-iodovinyl nortestosterone derivatives displayed high binding affinity for the human PR, that of Z-IPG1 and E- and Z-IPG2 being even higher than that of ORG2058. Their affinities for the rat PR were somewhat lower, especially those of both E-isomers. The affinity of IPG3 was lower for both the human and rat PR. The nortestosterone derivatives also showed AR binding, the relative binding affinities ranging from 4.3 to 17.0% as compared with 5alphaDHT. Additionally, neither of these steroids displayed any significant binding to either SHBG or CBG in human plasma. We conclude that the in vitro binding properties of all four 17alpha-iodovinyl nortestosterone derivatives warrant evaluation of the distribution characteristics of their 123I-labelled analogues to determine their usefulness as PR imaging agents. 相似文献
284.
The patch-clamp technique was used to characterise the ion channels in cells located in the mid region of mouse jejunal crypts. Six different channels were seen. A large outwardly rectified K+ channel (BK) (conductance, g at 0 mV = 92 +/- 6 pS), which was highly selective for K+ [PK+ (1) > PRb+ (0.6) > PCs+ (0.09) approximately PNa+ (0.07) > PLi+ (0.04)], had a low, voltage-independent open probability (Po) in the on-cell (O/C) configuration and appeared in 66% of the patches. In inside-out (I/O) patches, this channel had a linear current/voltage (I/V) relationship (g = 132 +/- 3 pS), Po was voltage dependent and it was blocked by cytoplasmic Ba2+ (5 mmol/l). An intermediate K+ channel (IK) which was present in 49% of O/C patches, had a linear I/V (g = 38 +/- 3 pS), ran-down in O/C patches, and was not seen in I/O patches. A number of smaller channels (SC) with conductances ranging from 5 to 20 pS were seen in 16% of O/C patches. Also present in the basolateral membrane were a Cl- channel (ICOR) and a nonselective cation channel (NSCC). These channels were only seen in I/O patches. ICOR had an outwardly rectified conductance (g at 0 mV = 36 +/- 2 pS), its Po was independent of voltage and unaffected by variations in cytoplasmic Ca2+ (100 nmol/l to 1 mmol/l) or ATP (0-1 mmol/l). The NSCC had a linear conductance (20 +/- 1 pS), its Po increased with depolarisation and elevation of cytoplasmic [Ca2+] (> or = 10 micromol/l), but was reduced by cytoplasmic ATP. None of the basolateral channels described here were activated by cAMP-dependent secretagogues, although a Cl- conductance was activated. This cAMP-dependent Cl- conductance was distinct from the basolateral Cl- channel and thus is most likely located in the apical membrane. 相似文献
285.
VA Cherekaev UB Makhmudov LV Osolodchenko SV Taniashin AG Vinokurov 《Canadian Metallurgical Quarterly》1998,17(3):25-31
PURPOSE: To determine differences in temperature for very low birth weight (VLBW) infants when swaddled and unswaddled in heated, double-walled incubators. DESIGN: A crossover design was used with infants receiving both the swaddled and unswaddled conditions. SAMPLE: 15 very low birth weight infants (< 1,500 gms) with postconceptional ages of 29.1 +/- 1.5 weeks. MAIN OUTCOME VARIABLE: Infant temperature in swaddled and unswaddled conditions. RESULTS: Abdominal temperatures during swaddling were 0.2 degree C higher than the unswaddled condition. In the swaddled condition, infants required a lower incubator temperature (mean = 26.9 +/- 0.4) than when unswaddled (mean = 29.8 +/- 0.5). 相似文献
286.
The influence of a single oral dose of nicardipine 30 mg on the pharmacokinetics and pharmacodynamics of propranolol 80 mg given as a conventional release formulation and as a slow release formulation was studied in two separate groups of 12 healthy volunteers. Nicardipine doubled the area under the curve (AUC) and Cmax of propranolol when given as a conventional formulation, but increased it only slightly when given as a slow release formulation. This pharmacokinetic interaction did not result in clinically relevant changes in pharmacodynamic responses. These results indicate that the enhancement of the bioavailability of propranolol by coadministration of nicardipine is dependent on the delivery rate of propranolol, suggesting that the interaction is mainly due to short-term haemodynamic effects of nicardipine leading to saturation of hepatic enzymes or functional shunting. 相似文献
287.
Workers engaged into subsurface extraction of sand containing gold were proved to work in difficult conditions characterized by stable negative temperatures, high concentrations of dust, elevated levels of noise and vibration. The drill operators demonstrated extremely unfavorable changes of physiologic processes within a shift. Those changes were compromised cardiovascular regulation, early occurrence and intensive progress of fatigue. The authors provide recommendations to normalize the work conditions and to create rational scheme of work and rest for the occupations. 相似文献
288.
JT Weststrate WC Hop AG Aalbers AW Vreeling HA Bruining 《Canadian Metallurgical Quarterly》1998,24(8):815-820
OBJECTIVE: To evaluate whether the Waterlow pressure sore risk (PSR) scale has prognostic significance for intensive care patients. DESIGN: A prospective study. SETTING: The surgical intensive care unit (ICU) of the University Hospital Rotterdam. PATIENTS: Data were evaluated from 594 patients who had been admitted to the ICU during the year 1994. METHODS AND RESULTS: Each patient was assessed daily with respect to their Waterlow PSR score and the development of pressure sores in the sacral region. Actuarial statistical methods were used to analyse the predictive value of the risk score. When a patient had a Waterlow PSR score > 25 on admission, the risk of developing a pressure sore was significantly increased compared to patients with a PSR score < 25. After admission, the daily Waterlow PSR scores obtained were significantly associated with the risk of developing a pressure sore. For each additional point this risk increased by 23% (95% confidence interval 17 to 28%). CONCLUSIONS: The Waterlow PSR scale provides the medical and nursing staff at an early stage with reliable information about the risk patients have in developing a pressure sore. 相似文献
289.
AG Kamel N Maning S Arulmainathan S Murad A Nasuruddin KP Lai 《Canadian Metallurgical Quarterly》1994,25(4):650-653
A study conducted at the Tampin Drug Rehabilitation Center in Malaysia established a high prevalence (23%) of asymptomatic carriers of Cryptosporidium among exposed HIV positive intravenous drug users (IVDUs). A majority of them were young adults and among the ethnic groups, the Malay HIV positive inmates had the highest prevalence of Cryptosporidium infection. 相似文献
290.
OA Kiseleva AG Travkin VS Grishina TKh Petrova OG Davydova 《Canadian Metallurgical Quarterly》1998,114(6):15-17
Condition was studied of collective specific immunity against diphtheria in vaccinated children who ranged from 2 to 15 years old, living in the industrial region of Pridneprovye, with special reference for the degree of the technogenous environmental pollution. To determine specific cellular sensibilization to diphtherial antigen. LAIT was used for the first time. The studies made showed that in a region under health-hazard conditions lower level of antitoxic antidiphtherial immunity occurs more frequently than in non-polluted areas (twice as much of the values), which fact suggests that technologeous pollution may have a suppressive effect on formation of postvaccinal immunity. Apart from measuring the level of specific antibodies for control of the formation of the immune responsiveness to be monitored you may use LAIT and measure levels of R-proteins. 相似文献