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991.
Transurethral resection of the prostate is the most common surgical treatment for benign prostatic hyperplasia. We conducted a prospective randomized clinical trial to compare this surgery with medical treatment in men with moderate symptoms of benign prostatic hyperplasia. Of 98 men over the age of 54 years who were screened between June 1993 and June 1995, 53 were studied (25 in the surgery group and 28 in the medication group). Patients' symptoms and the degree to which they were bothered by urinary difficulties were measured with standardized questionnaires and medical evaluations. The men randomly assigned to the surgery group underwent surgery within 2 weeks after the assignment. Surgery was not associated with an impotence or urinary incontinence. The follow-up period was 1 year. Surgery was significantly associated with improvement in residual urinary volume and peak flow rate; and also in the scores for urinary difficulties, sexual performance and interference with activities of daily living (P < 0.001 for all comparisons). We concluded that for patients with moderate symptoms of benign prostatic hyperplasia, surgery is more effective than medication in improving genitourinary symptoms and enhancing the quality of life. Thus, medication as treatment should be reserved for patients who are less bothered by urinary difficulty or who wish to delay surgery. 相似文献
992.
993.
The letter describes the recently developed fastest time-division switch experimental system operating at 512 Mbit/s. The system adopts a new switch structure which can increase switching throughput by four times over the basic structure to ensure high-speed performance. Also employed in the switch are two types of peripheral logic developed using Si bipolar super-self-aligned process technology. This switch makes possible the ISDN time-division switches necessary for TV and high-definition TV communication. 相似文献
994.
G Kawa S Nagao A Yamamoto K Omori Y Komatz H Takahashi Y Tashiro 《Canadian Metallurgical Quarterly》1994,4(12):2040-2049
Recently, it has been reported that Na,K-ATPase in the renal epithelia of human autosomal dominant polycystic kidney disease and cpk mouse, a murine model of autosomal recessive polycystic kidney disease, mislocates to apical plasma membrane and that mislocated Na,K-ATPase causes the cyst formation. Whether the DBA/2FG-pcy mice, which are presumably a suitable model for autosomal dominant polycystic kidney disease, also exhibit the reversal polarity of Na,K-ATPase localization was examined. Kidneys of newborn DBA/2FG-pcy mice, and those at early and late stages of cyst development were examined by immunohistochemical techniques. At any stage, abnormal distribution of Na,K-ATPase on the apical membranes of tubular epithelial cells could not be detected. It is suggested that cysts can be formed without reversed polarity of Na,K-ATPase distribution in pcy mice. 相似文献
995.
We demonstrate a novel multiple-valued logic (MVL) gate using series-connected resonant tunneling devices. Logic operation is based on the control of the switching sequence of these devices through the modulation of their peak currents by the input signal. We obtain the literal function, one of fundamental MVL functions, by integrating three InGaAs-based resonant-tunneling diodes with two HEMT's on an InP substrate. The gate configuration is greatly simplified compared with a conventional literal gate employing CMOS circuits 相似文献
996.
Salmonella typhimurium shows an attractant response to citrate and a repellent response to phenol, and a chemoreceptor mediating these responses has been identified and named Tcp (taxis to citrate and away from phenol). Tcp is one of the methyl-accepting chemotaxis proteins that have a molecular mass of approximately 60 kDa estimated by SDS/PAGE, and its methylation level is increased by citrate and decreased by phenol. Tcp also mediates an attractant response to metal-citrate complexes. The complete nucleotide sequence of the tcp coding region has been determined. The deduced amino acid sequence of Tcp, consisting of 547-amino acid residues, is homologous with that of the aspartate chemoreceptor of S. typhimurium. Thus, Tcp is another member of the bacterial transmembrane chemoreceptor family. Because citrate is a good carbon source for S. typhimurium but is not a carbon source for the closely related species Escherichia coli and because citrate utilization is used as a key diagnostic character to distinguish these species, it is reasonable to assume that Tcp is specific to S. typhimurium. 相似文献
997.
The present study was designed to find the reliable parameter(s) for the detection of early neurotoxicity following intracarotid (IC) administration of cisplatin. IC administration was performed for 60 minutes in female Wistar rats derived into four groups according to the dose given (1 mg, 1.2 mg, and 1.5 mg of cisplatin, and normal saline in control rats). Blood-brain barrier (BBB) permeability and local cerebral blood flow (LCBF) were measured by a double-tracer autoradiography technique using 1-[14C]-alpha-aminoisobutyric acid (14C-AIB) and 4-[18F] fluoroantipyrine (18F-FAP), respectively. Blood chemistry and neuropathology were also examined. BBB permeability was increased only on the ipsilateral side. This increase was dose-dependent, preceded the brain necrosis, and was statistically significant in the hypothalamus (1.2 mg group), auditory cortex and caudoputamen (1.5 mg group). Renal dysfunction was often observed. The changes in the LCBF did not occur until brain necrosis was noticeable. These findings demonstrate that the increase in the BBB permeability provides a sensitive and reliable indication of an early toxicity to brain tissue following IC administration of cisplatin. 相似文献
998.
Tanaka K. Wakao K. Yamamoto T. Nobuhara H. Fujii T. 《Photonics Technology Letters, IEEE》1993,5(6):602-605
An internal efficiency of 91% was obtained with In0.7Ga 0.3As/InGaAsP strained-layer multiple quantum well (MQW) lasers emitting at a wavelength of 1.5 μm. The dependence of the reciprocal differential quantum efficiency on the length of the laser cavity shows that the absorption loss in the InGaAsP (λ=1.3 μm) confinement layer caused by carrier overflowing into the confinement layer reduces the internal efficiency 相似文献
999.
A new multivariate statistical quality control method has been developed. It is an extension of the method developed by Kume, which is able to find abnormal values in multivariate biochemical data of a clinical laboratory. The present method makes use of the difference between two sets of data measured from the samples of the same patient obtained on different days. The Mahalanobis' distance between two samples can be calculated from the difference of their observations. If the Mahalanobis' distance of the two data is larger than the critical value decided in advance, the reliability of the measurement is doubtful. The characteristic of the present method is that it can apply to data with missing values by estimating them from measured data. Some numerical examples are shown to demonstrate the availability of the method. 相似文献
1000.
Yamamoto Osamu Li Shenghua Sasamoto Tadashi 《Journal of Materials Synthesis and Processing》1998,6(3):203-207
Well-crystallized LiSb(OH)6 powders with a hexagonal structure were prepared by chemical bath deposition. The thermal decomposition of as-prepared samples was examined. In order to obtain LiSb(OH)6 powders, it was essential to use tartaric acid as a stabilizing agent for antimony ion and to add LiOH above pH 9 into the precursor solution. The crystal structure of the samples obtained was of hexagonal phase. The increase in pH value and keeping temperature indicated that the shape of samples changed from granule particles to plate-like particles. The granule particles heated at 800°C consisted of orthorhombic LiSbO3. However, the plate-like particles resulted in the coexistence of both orthorhombic LiSbO3 and tetragonal Li3SbO4 相似文献