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排序方式: 共有678条查询结果,搜索用时 15 毫秒
81.
Specimens collected in several localities from Salta and Tucumán provinces (north-western Argentina) Liolaemus quilmes and L. ornatus (oviparous population), and L. alticolor (viviparous population) were dissected. The specimens of lizards examinated have nematodes, in stomach, fore-gut and cloaca, identified as Physaloptera lutzi Guimaraes, Cristófaro and Rodrigues, 1976. This represents the first record for this parasite from Liolaemus species in Argentina. Morphologic and morphometric parasitological studies were done. The specimens were drawn and photographed. Also, the following parasitic infection indexes were calculated: prevalence, mean and maximum intensity. 相似文献
82.
E Ishimura Y Nishizawa T Kawagishi Y Okuno K Kogawa S Fukumoto K Maekawa M Hosoi M Inaba M Emoto H Morii 《Canadian Metallurgical Quarterly》1997,51(6):1920-1927
Intrarenal hemodynamics were studied by duplex Doppler sonography in 112 inpatients with type II diabetes mellitus (DM; 65 males, 47 females, 58 +/- 13 years old). The resistive index (RI) and pulsatility index (PI) of the interlobar arteries were calculated. The patients were divided into four groups: group I consisted of patients with urinary albumin excretion (UAE) < 20 micrograms/min (N = 42), group II with 20 < or = UAE < 200 (N = 28), group III with UAE > or = 200 (N = 25), and group IV with serum creatinine > or = 1.5 mg/dl (N = 17). Both RI and PI values in groups II, III, and IV were significantly higher than those in the controls (age- and sex-matched healthy persons, N = 37; P < 0.001), and those in group IV were significantly higher than those in groups I, II, and III (P < 0.0001). Multiple regression analysis revealed that RI values in DM patients were significantly affected by creatinine clearance, age, and duration of diabetes (R2 = 0.554, P < 0.0001). When intima-medial thickness (IMT) of the femoral and carotid arteries were measured by B-mode ultrasonography, RI values were significantly correlated with both the femoral and carotid arterial IMT. These results demonstrate that intrarenal hemodynamic abnormalities are present in type II DM patients with nephropathy, and that intrarenal hemodynamics are affected by decreased glomerular function and also probably by advanced arteriosclerosis. 相似文献
83.
T Nishizawa M Furuhashi T Nagai T Nakai K Muroga 《Canadian Metallurgical Quarterly》1997,63(4):1633-1636
A molecular phylogenetic analysis of 25 isolates of fish nodaviruses, the causative agents of viral nervous necrosis of marine fish, was performed based on the nucleotide sequences (427 bases) of the coat protein gene. These fish nodaviruses were classified into four clusters: tiger puffer nervous necrosis virus, striped jack nervous necrosis virus, berfin flounder nervous necrosis virus, and red-spotted grouper nervous necrosis virus. 相似文献
84.
Access and metro networks based on WDM technologies 总被引:3,自引:0,他引:3
Iwatsuki K. Jun-ichi Kani Suzuki H. Fujiwara M. 《Lightwave Technology, Journal of》2004,22(11):2623-2630
This paper describes the technical issues of access and metro networks based on wavelength division multiplexing (WDM) technologies, some solutions, and an experimental demonstration. A WDM star access network with colorless optical network units (ONUs) is proposed. For realizing the colorless ONU, two approaches are introduced; optical carrier supply and spectrum slicing. In addition, a WDM metro ring network with scalable optical add/drop multiplexers (OADMs), namely the tapped-type OADM, is proposed to effectively accommodate the large amount of traffic issued from access networks. Prototypes are constructed and used to verify the feasibility of the proposed WDM technologies. 相似文献
85.
Jun-ichi Nishizawa Akihiko Murai Hiroki Makabe Osamu Ito Tomoyuki Kimura Ken Suto Yutaka Oyama 《Solid-state electronics》2004,48(12):2251-2254
The tunnel injection transit time (TUNNETT) diodes with p+p+n+n−n+ structure were fabricated by liquid phase epitaxy (LPE). About 100 Å tunnel junction (p+n+) was successfully prepared by the double impurity diffusion of Ge and S during LPE growth. Continuous wave (CW) oscillation was realized at 51.520 GHz in the V-band cavity with the phase noise of −60 dBc/Hz at 1 kHz bandwidth. 相似文献
86.
H Taniwaki Y Nishizawa T Kawagishi E Ishimura M Emoto T Okamura Y Okuno H Morii 《Canadian Metallurgical Quarterly》1998,21(11):1848-1855
OBJECTIVE: We assessed the effects of atherosclerosis on the glomerular filtration rate (GFR) in patients with type 2 diabetes and who had micro- or normoalbuminuria. RESEARCH DESIGN AND METHODS: A total of 61 Japanese patients with type 2 diabetes were recruited from inpatients of Osaka City University Hospital. They ranged in age from 40 to 69 years (28 men and 33 women). Each subject collected a 24-h urine sample for quantitative analysis of albumin. Absence of albuminuria was defined as a urinary albumin excretion level of <30 mg/24 h (n = 36) and microalbuminuria as a level of 30-300 mg/24 h. The GFR was estimated using 99mTc diethylenetriamine pentaacetic renogram method. As indexes of atherosclerosis, we measured the intimal-medial thickness (IMT) and distensibility of the carotid artery using high-resolution B-mode ultrasonagraphy and an echo-tracking system. We measured the resistance index (RI) of the renal interlobar arteries by pulsed Doppler sonography. RESULTS: The clinical characteristics of type 2 diabetic patients with and without microalbuminuria did not differ except for duration of diabetes, which was longer in the patients with microalbuminuria. GFR also did not differ between the patients with and without microalbuminuria. GFR was significantly correlated with the patient's age (r = -0.256, P < 0.05), carotid IMT (r = -0.326, P < 0.05), carotid stiffness beta (r = -0.449, P < 0.001), and renal arterial RI (r = -0.365, P < 0.05). In multiple regression analysis, independent factors associated with GFR were carotid IMT (R2 = 0.108, P = 0.0102), carotid stiffness beta (R2 = 0.208, P = 0.0003), and renal artery RI (R2 = 0.130, P = 0.0043). CONCLUSIONS: The decline in GFR in type 2 diabetic patients in the early stages of nephropathy may be due in part to atherosclerosis. 相似文献
87.
T Tsuchida Y Yonekura S Nishizawa N Sadato N Tamaki T Fujita Y Magata J Konishi 《Canadian Metallurgical Quarterly》1996,37(7):1237-1241
It is well known that many cerebral perfusion tracers underestimate cerebral blood flow in high flow range. A model has been proposed to correct nonlinear relationship of flow and uptake of the tracers that accounts for the permeability-surface area product (PS model). METHODS: We examined 43 patients in this study. To test the feasibility of this method for 123I-IMP, 99(m)Tc-HMPAO and 99(m)Tc-ECD, radioactivity ratios of cerebral regions to cerebellum (C/Cr) on SPECT images were compared with those of rCBF (F/Fr) measured by PET using the 15O CO2 steady-state method. Coefficient for correction in the PS model was estimated by the least squares method, and SPECT data were corrected using these coefficients. RESULTS: Estimated PS value by this method was highest in IMP (116 ml/min/100 g) followed by ECD (66 ml/min/100 g) and HMPAO (46 ml/min/100 g). The corrected SPECT data demonstrated an excellent linear relationship, which was close to unity, with rCBF. CONCLUSION: These results indicate that the PS model can be used for nonlinearity correction of brain perfusion SPECT. 相似文献
88.
Takeo Ohno Yutaka Oyama Ken Suto Jun-ichi Nishizawa 《Materials Science in Semiconductor Processing》2003,6(5-6):417-420
Low-temperature (290°C) area-selective regrowth by molecular layer epitaxy (MLE) was applied for the fabrication of an ultra-shallow sidewall (50 nm) GaAs tunnel junction. Fabricated tunnel junctions have shown a record peak current density up to 35,000 A/cm2. It is shown that the tunnel junction characteristics are strongly dependent on the sidewall orientation and the AsH3 surface treatment conditions just prior to regrowth. The effects of AsH3 surface treatment are discussed in view of the control of surface stoichiometry. 相似文献
89.
Y Tamagawa K Kitamura T Ishida H Hagiwara K Abe M Nishizawa 《Canadian Metallurgical Quarterly》1996,116(6):796-798
A mitochondrial DNA mutation at nucleotide 1555 in the ribosomal RNA gene was recently reported as a cause of maternally inherited non-syndromic sensorineural deafness. We assumed that the 1555 mutation is also associated with sporadic non-syndromic deafness and screened for the mutation in seven randomly selected sporadic cases with bilateral sensorineural hearing loss of unknown etiology. The mutation was found in one patient, who first noticed hearing loss when she was in her early teens with subsequent gradual progression. The results suggest that the 1555 mutation may contribute to the etiology of idiopathic bilateral sensorineural hearing loss in some cases. 相似文献
90.
T Yokoyama K Sugiyama S Nishizawa T Tanaka N Yokota S Ohta K Uemura 《Canadian Metallurgical Quarterly》1998,140(12):1287-90; discussion 1291
The neural activity pattern of the subthalmic nucleus (STN) was investigated in five patients with Parkinson's disease who were scheduled for electrode implantation for chronic stimulation of the STN. The initial target was placed 8 mm or 10 mm lateral to the midline, 3 mm to 4 mm posterior to the midcommissural point, and 5 mm to 6 mm below the intercommissural (AC-PC) line. The STN was identified by semi-microelectrode recordings with a trajectory moving laterally in 2-mm steps. The amplitudes of multi-unit activities were relatively low at depths from 8 mm to 5 mm above and from 1 mm to 4 mm below the target, while those 4 mm to 0 mm above the target were significantly higher than at the other sites (ANOVA, Fisher's test, p < 0.05), with the highest amplitude at 2 mm above the target (91.0 +/- 23.3 mu v, n = 15). In the mediolateral direction, amplitudes were relatively higher in the lateral portion, and amplitudes at 14 mm lateral to the midline were significantly higher than at the other sites (ANOVA, Fisher's test, p < 0.05). The target for chronic electrical stimulation was determined to be at the midpoint of the hyperactive STN, i.e., 12 mm lateral to the midline in three patients and 13 mm lateral in two patients. Movement-related neural activity was observed at 5 sites, i.e., 3 sites responded to passive movement of the contralateral wrist and 2 sites to passive knee and/or ankle movement. In conclusion, our data show that the lateral part of the STN is hyperactive in PD, and recordings of neural activities contributed greatly to identifying the STN and determining the target for chronic stimulation within it. 相似文献