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21.
22.
The excitatory responses of deflationary slowly adapting pulmonary stretch receptor (SAR) activity to lung deflation ranging from approximately -15 to -25 cm of H(2)O for approximately 5 s were examined before and after administration of flecainide, a Na(+) channel blocker, and K(+) channel blockers, such as 4-aminopyridine (4-AP) and tetraethylammonium (TEA). The experiments were performed in anesthetized, artificially ventilated rats after unilateral vagotomy. The deflationary SARs increased their activity during lung deflation and its effect became more pronounced by increasing the degree of negative pressure. During lung deflation the average values for the deflationary SAR adaptation index (AI) were below 40%. Intravenous administration of veratridine (50 microg/kg), an Na(+) channel opener, stimulated deflationary SAR activity: one maintained excitatory activity mainly during deflation and the other receptors showed a tonic discharge during both deflation and inflation. Despite the difference in deflationary SAR firing patterns after veratridine administration, flecainide treatment (6.0 mg/kg) blocked veratridine-induced deflationary SAR stimulation and also caused strong inhibition of the excitatory responses of deflationary SARs to lung deflation. Under these conditions, the average values for deflationary SAR AI were over 90%. The responses of deflationary SARs and deflationary SAR AI to lung deflation were not significantly altered by pretreatment with either 4-AP (0.7 and 2.0 mg/kg) or TEA (2.0 and 6.0 mg/kg). These results suggest that the excitatory effect of lung deflation on deflationary SAR activity is mediated by the activation of flecainide-sensitive Na(+) channels on the nerve terminals of deflationary SARs.  相似文献   
23.
Y Matsuki  K Suzuki  M Hara  A Kitani  T Hirose  M Harigai  M Kawakami  N Tanaka  M Kawagoe  H Nakamura 《Ryūmachi》1992,32(2):154-9; discussion 159-62
Arterial thrombosis is one of the major symptoms of antiphospholipid syndrome (APS). However, thrombosis in a primary branch of the aorta has rarely been reported in APS. We report here a case of APS complicated by thromboses in both the left subclavian artery and the left external iliac vein. A 32-year-old woman was admitted in May, 1990 complaining of no pulse in the left superficial arteries (e.g., left radial artery) for the past 5 years and acute swelling of the left lower extremity. A left ascending phlebography showed an occlusion of the external iliac vein and arteriography revealed obstruction in the left subclavian artery. Collateral circulations were developed at the site of each thrombus. Clotting and immunological studies revealed a prolonged APTT, a high titer of anticardiolipin antibody and lupus anticoagulant positive. We ruled out various diseases and clinical risk factors predisposing to both arterial and venous thromboses. Accordingly, we concluded that both thromboses were based on APS. Following treatment with anticoagulants, aspirin and corticosteroid, the swelling of her left thigh was diminished and the antibody titer was decreased within 3 months.  相似文献   
24.
We designed an intraocular lens (IOL) with spring action, which we call the Spring IOL, with the idea of providing a slight but adequate accommodative power. The Spring IOL consists of two 6.0-mm optics, held 4.38 mm apart, and four flexible loops. The optics are made of polymethylmethacrylate (PMMA) and the loops of polyvinylidene fluoride. The lens's refractive power is provided by the anterior optic; the posterior optic acts as a footplate to restrict the anteroposterior movement of the anterior optic. By torsionally compressing the obliquely arranged loops, a 10.0-mm 3-dimensional IOL can be reduced to 6.0 mm and inserted in the capsular bag through a 3.5-mm capsular opening. Because the Spring IOL is made of the same materials as conventional IOLs, most of the problems hindering the development of a refilling material (which could also provide accommodation) are avoided. In this first report we discuss the design of the lens, the refractive theory involved, and our experience inserting it in an excised animal eye.  相似文献   
25.
We report a 73-year-old woman with typical clinical, histological and immunofluorescence features of pemphigoid nodularis. Direct immunofluorescence studies of prurigo nodularis-like lesions and peribullous skin showed the linear deposition of IgG and C3 at the basement membrane zone. Circulating IgG against the basement membrane was also detected by indirect immunofluorescence. The serum from the patient was shown to contain the autoantibody against 230 kDa hemidesmosomal antigen associated with bullous pemphigoid antigen.  相似文献   
26.
Angiogenesis is an independent prognostic indicator in breast cancer. In this report, the relationship between expression of vascular endothclial growth factor (VEGF; a selective mitogen for endothelial cells) and the microvessel density was examined in 103 primary breast cancers. The expression of VEGF was evaluated by immunocytochemical staining using anti-VEGF antibody. The microvessel density, which was determined by immunostaining for factor VIII antigen, in VEGF-rich tumors was clearly higher than that in VEGF-poor tumors ( P <0.01). There was a good correlation between VEGF expression and the increment of microvessel density. Furthermore, postoperative survey demonstrated that the relapse-free survival rate of VEGF-rich tumors was significantly worse than that of VEGF-poor tumors. It was suggested that the expression of VEGF is closely associated with the promotion of angiogenesis and with early relapse in primary breast cancer.  相似文献   
27.
Endocrine tumor of the pancreas is potentially malignant. A multicenter analysis of these tumors was conducted to clarity the present status of their surgical management and the subsequent long-term surgical results. The Japan pancreatoduodenectomy (JPD) study group carried out the study; 368 patients were enrolled and variables related to tumor characteristics, surgery, and survival were retrospectively analyzed. There were 222 patients with functioning tumor and 143 patients with nonfunctioning tumor. Malignant tumor was found in 140 of 368 (38%) of the patients, and 63/140 (45%) of these patients had metastatic lesion; the most common site of the metastasis was liver 34/136 (25%), followed by regional lymph nodes 26/136 (19%). Pancreatic resection was performed in 91% of patients with nonfunctional tumor and in 83% of those with malignant tumor, and 73% of the pancreatic resections were done with lymph node dissection. The overall 5-year actuarial survival rate was 76% in patients with malignant tumor. The actuarial 5-year survival rate was 93% in the patients without metastasis and 83% in patients who received curative resection. Multivariate analysis showed that the presence or absence of synchronous metastasis was the sole significant prognostic factor. The results suggest that: (i) malignant endocrine tumor of the pancreas is a curable malignancy when pancreatic resection with lymph node dissection is adopted and (ii) that synchronous metastasis is the dominant prognostic factor. This study was carried out as a group project. The authors' institutions are as follows  相似文献   
28.
The aim of this study was to assess the significance of C3 deposition in IgA nephropathy in children and adolescents. One hundred and two patients aged 5–21 years (57 male and 45 female) were studied. The findings of C3 deposition were classified into 8 groups by immunofluorescent (IF) pattern and intensity as follows: group MC3+ (N = 12): mesangiocapillary pattern and 3+ in intensity; group MC2+ (N = 13): mesangiocapillary and 2+; group MC1 + (N = 4): mesangiocapillary and 1 +; group M3+ (N = 11): mesangial and 3+; group M2+ (N = 24): mesangial and 2+; group M1 + (N=18): mesangial 1 +; group S (N = 12): only segmentally positive; and group N (N = 8): negative. Histological changes were scored semiquantitatively as an activity index (cellular proliferation, necrosis, interstitial cell infiltration, and cellular crescents) and a chronicity index (mesangial sclerosis, segmental and global glomerular sclerosis, fibrous crescents, adhesion and tubulo-interstitial change). IF findings were scored semiquantitatively and laboratory findings were also studied. The following results were obtained: 1) The scores of total activity index in MC groups were higher than in the M, S or N groups, and the greater the degree of C3 deposition, the higher the score; 2) Such result was not evident in the chronicity index; 3) High IF scores of IgG and IgM were found in the MC3+ and MC2+ groups; 4) Hematuria was more severe in MC3+ and MC2+ than in other groups, and proteinuria was more prominent in the MC than other groups. Thus the degree of C3 deposition was parallel with histological activity and urinary findings.  相似文献   
29.
A case of bilateral blepharospasm who registered the efficacy of edrophonium was reported. The case is a 49-year-old female. She had been in good health until January, 1991 when she complained of difficulty in opening her eyes while driving. Thereafter the condition progressed to such a degree that she was unable to experience a comfortable life. Her blinking rate did not changed. The symptoms were triggered by stress or some physical action, such as walking or driving. They were attenuated by taking a bath, sleep or sedation. The severity of the symptoms varied during the day and from day to day. Neurological examination revealed bilateral spasms of the orbicular oculi muscles, and occasionally of the orbicular oris muscles, sternocleidmastoid muscles and the perinasal regions. Neither orolingual dyskinesia nor other involuntary movements were detected. Surface electromyography (EMG) disclosed tonic discharges mainly from the orbicular oculi muscles. The abnormal spasm disappeared with the injection of edrophonium chloride. The test for the serum antiacetylcholine receptor antibody was negative and a repetitive stimulation EMG showed no waning phenomenon. No thymoma or thymus abnormalities were detected by pneumomediastinography. A needle EMG revealed neurogenic change in the distal portion of the limbs. A single fiber EMG showed elongation of the jitter value and the blocking phenomenon. Although distigmine bromide was ineffective against the spasm, pyridostigmine bromide and the local injection of botulinum toxin were very effective.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
30.
Many reports about the increase of renal cell carcinoma patients have been published in Japan recently, however, the real fluctuations in the total number of patients in relation to the change of population have not been reported yet. Most of the patients with renal cell carcinoma in the last 10 years were examined in Chiba prefecture, which has a population of about five million and 25 active urological offices. Histologically confirmed cases were investigated by sending questionnaire letters. The items were as follows; sex, age, address, occupation, family history, past history, symptoms, examination methods that first detected the tumor, operation date, tumor diameter and clinical stage. Twenty two offices returned answers and 560 cases who lived in Chiba were found to have renal cell carcinoma from 1980 to 1989. Yearly incidence rates per 100,000 persons demonstrated a significant increase from 0.32 to 2.07. Small, asymptomatic and low stage cancers have been increasing rapidly, however, the rate of metastatic disease has not shown any decrease. The main cause of rapid increase seems to be attributed to progress in diagnostic methods and increase of early detection, but the possibility of an increase in some carcinogenic factors can not be ruled out.  相似文献   
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