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121.
E Hire Z Bánsághi D G?r?g E Makó P Nagy L Sréter Z Tulassay 《Canadian Metallurgical Quarterly》1996,137(38):2093-2096
Leiomyomas are uncommon benign tumors of smooth muscle which may occur wherever smooth muscle is present. The small bowel is the most frequent site. Bleeding is the most common presenting symptom. Other symptoms, nausea, vomiting, abdominal pain are rare. In this article a 44 year-old male, presented, who was admitted with intermittent gastrointestinal bleeding in requence of jejunal leiomyoma with exulceration. 相似文献
122.
Proximity-coupled U-slot patch antenna 总被引:1,自引:0,他引:1
The design and experimental results of a proximity-coupled U-slot microstrip antenna are presented. The impedance bandwidth (VSWR⩽2) of the antenna is 20%, centred at 4.3 GHz. It has an average gain of 7.5 dBi and a cross-polarisation of about -20 dB. Both gain and radiation patterns were measured across the passband. An essential feature in the design is that a Π-shaped feed line is connected at the end of the usual microstrip line 相似文献
123.
JM Mak 《Canadian Metallurgical Quarterly》1997,26(6):1086-1090
Cancer is a major health problem world-wide. Therefore, it is not surprising that cancer is identified as the top priority disease group for an improvement programme by the Hospital Authority in Hong Kong. Laser therapy for patients with nasopharyngeal carcinoma, for example, is evidence of the advancement of the scientific and technological developments for cancer treatment. Furthermore, the establishment of the Cancer Centre has provided ample opportunities for clinical practices and research studies. In response to the proclamation of the 'urgent need for the establishment of a cancer society in every country' by Searle in 1990, the Oncology Care Society of Hong Kong, which aims to promote both cancer education and cancer research, was established in 1993. Adopted from the core curriculum of the European Oncology Nursing Society, the specialist course of cancer nursing care was first implemented in Hong Kong in 1993 and the nurse specialist is now a permanent part of nursing career structure in Hong Kong. This paper attempts to review the development of oncology nursing in Hong Kong according to these factors and to find ways to improve the current situation. 相似文献
124.
A new application designated as the “System Alarm Function” is made possible by using the “Unsolicited Inbound” capability recently developed for the Two Way Automatic Communication System (TWACS) System-10, which is already used by several electric utilities in the USA for demand side management, remote metering and distribution automation is reviewed here. The “Unsolicited Inbound” algorithm development, the operational issues that are pertinent to the understanding of collisions between multiple alarms and the effects on the “alarm response time” are discussed in detail. This master-to-master relationship between remote transponders in the distribution network and the central control computer opens the door to multiple functional capabilities in the area of distribution automation and remote monitoring 相似文献
125.
The petroleum geology of Cambodia has been studied less than has that of the neighbouring countries in Indochina. Nevertheless, the results of recent geological, remote- sensing and limited seismic investigations (the latter on the Cambodian Shelf area of the Gulf of Thailand) have allowed identification of sedimentary basins favourable for hydrocarbons exploration (both on- and offshore), and, consequently, the delineation of prospective areas. Six possibly oil- and gas-bearing basins have been identified, namely: the Siam (northern portion: in the Gulf of Thailand), Tonle Sap, Khorat (southern portion), Preah, Chung and Svairieng Basins. 相似文献
126.
The prevalence of pyruvate kinase (PK) deficiency among the Chinese population has not been established. Fung et al. (Arch Dis Child 44:373-376, 1969) and Wu et al. (Am J Hematol 20:139-144, 1985) indicate 3.4% and 2.1% PK deficiency prevalence rates, respectively, the higher figure based on Beutler's screening test [3] without confirmatory testing. Neither figure is consistent with the occurrence of hemolytic anemia from this cause in the experiences of hematologists in Hong Kong. Using the standard quantitative assay, we measured PK activity in blood samples from 1,100 local Chinese people. The assay was automated on a centrifugal analyser, and the results were expressed in IU per gram of hemoglobin (IU/g Hb). Blood samples from 497 healthy male adults were measured, and PK activity was found to have a range of 15.2 +/- 5.2 (mean +/- 2 SD). A total of 100 cord blood samples were also measured, and the reference interval for this subgroup was 17.7 +/- 4.8. Additionally, samples from 503 anaemic patients were measured, and all were found to have values above the lower limit of the reference interval. The prevalence of PK deficiency among the Hong Kong Chinese population determined by this study was < 0.1%. 相似文献
127.
BACKGROUND: Adult-onset minimal-change nephropathy has been associated with a slower response to corticosteroids and a less benign prognosis when compared to children. However, there are few long-term outcome data reported. METHODS: We have reviewed retrospectively 51 idiopathic adult-onset minimal-change nephropathy patients investigated and treated at a single centre. RESULTS: Male to female ratio was 1:1.4, mean age at diagnosis was 37 years, and average length of follow-up was 14.1 years. Significant comorbidity was identified in 33%. A raised serum creatinine was found in 55% but returned to normal almost invariably upon remission. At presentation, hypertension was found in 47% of patients, microscopic haematuria in 33%, hypercholesterolaemia and hypertriglyceridaemia in 96%, and hyperuricaemia in 42%. Remission (complete or partial) was achieved by 46, 70 and 92% within 4, 8 and 21 weeks respectively, in patients treated with steroids; steroid resistance was encountered in 8%. The time to remission was positively correlated with age (P = 0.002) and initial albumin level (P = 0.005), and negatively correlated to the number of subsequent relapses (P = 0.029); 33% of patients had a spontaneous remission at some time during the disease course. Patients with multiple relapses were treated with cyclophosphamide and 63% of them had remained in remission after 5 years. Hypertension was present in 25% of patients after an average interval of 11 years. At the time of the final follow-up, only three patients had a raised creatinine and all but three patients were in complete remission. CONCLUSIONS: Adult-onset minimal-change nephropathy shares the same good long-term outcome as the childhood counterpart, with sustained remission and preserved renal function. 相似文献
128.
A review is presented of the existing finite element models developed from 1987 to 1996 for the biomechanics of lower-limb prostheses. Finite element analysis can be a useful tool in investigating the mechanical interaction between the residual limb and its prosthetic socket, and in computer-aided design and computer-aided manufacturing of prosthetic sockets. Various assumptions and simplifications are made in these models to simplify the actual problem with complex geometry, material properties, boundary and interfacial conditions, as well as loading situations. The analyses can provide the information on the stress distribution at the stump/socket interface and within the residual limb tissues. More recently, nonlinear models have been developed taking into consideration the process of socket rectifications, the slip/friction conditions and material large deformation. The models so far developed have provided some basic understanding of the biomechanics. Comparison of the predictions of these models with experimental measurements indicated that the predicted stresses were within the ranges measured, although one-to-one correspondence was difficult to achieve. Further research is still required in order to improve these models to obtain higher precision in the results taking into account nonlinear and dynamic effects. 相似文献
129.
130.
Conventional guided-wave optical polarization splitters exhibit poor polarization extinction characteristics because of the necessity of controlling waveguide parameters. In order to improve the characteristics, an electrical control scheme was investigated in an alternating Δβ directional coupler. Polarization-dependent electrooptic as well as polarization-independent plasma effects were employed to produce high extinction for two orthogonal polarizations independently. As a result, an extinction ratio as high as 32 dB was obtained with a fabricated GaAs-GaAlAs device. This is the highest value ever reported with a channel waveguide device 相似文献