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71.
The plasminogen activating system plays an important role in the progression of carcinomas and the significance of this system in various carcinomas has been thoroughly investigated. To follow up these investigations, we examined the immunolocalization of the components of the plasminogen activating system, namely the urokinase-type plasminogen activator (uPA), its receptor (uPAR), and two inhibitors (PAI-1 and PAI-2), in 72 cases of breast carcinomas. uPA, uPAR and PAI-1 were uniformly expressed in 75.0%, 84.7% and 80.6% of the cases respectively, although their expression was less uniform in T3 or larger carcinomas (p<0.05). Furthermore, the immunoreactivities of these three proteins were often very similar in the lesions. PAI-2 expression was, to the contrary, statistically less extensive (p<0.01)than PAI-1, and only 52.8% of the cases were uniformly positive. The incidence of PAI-2 expression was statistically lower in T3 or larger carcinomas (p<0.01), and in stage III (p<0.01) and grade III carcinomas (p<0.05). Moreover, PAI-1 immunoreactivity was more commonly found in lymph node positive (p<0.05), T3 or larger and stage III carcinomas than PAI-2 immunoreactivity. These findings suggest that uPA, uPAR and PAI-1, whose expression should be regulated by carcinomas once they have grown to a certain degree, work in association with one another, probably promoting carcinoma progression, while PAI-2 might act as the inhibitor in this system. Furthermore, breast carcinomas containing more PAI-I than PAI-2 are more active in respect to both local proliferation and metastasis.  相似文献   
72.
Using the polymerase chain reaction and single-strand conformation polymorphism analysis, p53 gene mutations were examined in 24 cases of ovarian tumor including 14 ovarian carcinomas and 2 borderline cases of common epithelial type, 7 germ cell tumors, and one stromal tumor. Abnormal bands indicating mutations were detected in 12 (50%) of the cases examined, being present most frequently in common "epithelial" ovarian carcinoma (71%, 10/14). One case each of squamous cell carcinoma originating in a dermoid cyst and anaplastic dysgerminoma were positive for mutation. Direct sequencing confirmed 12 mutations and revealed G-->A and G-->C nucleotide changes in 5 and 3 cases (42% and 25%), respectively. The mutation was localized at the CpG site of the gene in 3 cases. Immunohistochemical examination of p53 protein in 21 cases and DNA flow-cytometrical analysis in 17 cases were also performed. Nuclear accumulation of the p53 protein and DNA aneuploidy pattern were detected in 11 (52%) and 9 (53%) cases, respectively. These were significantly correlated with p53 gene mutation (P < 0.01 and P < 0.05, respectively; Fisher's exact test). Neither mutation of the p53 gene, nuclear accumulation of p53 protein nor DNA aneuploidy was detected in borderline cases of common "epithelial" type, typical dysgerminoma and immature teratoma. These results suggest that p53 gene mutation, nuclear accumulation of the protein and the DNA aneuploidy pattern are events occurring almost simultaneously in the progression of ovarian tumors, and that p53 abnormalities seem to be correlated with a high grade of malignancy.  相似文献   
73.
Despite all of the protections promised through grandfathering and pathways to educational mobility, the entry movement tends to be perceived by many to be "demoting" the lives and livelihoods of hundreds of thousands of RNs who do not possess the education to meet the proposed standard. Here is a proposal for a way out of the quagmire.  相似文献   
74.
The cardiac response to dietary salt loading was assessed by Doppler echocardiography during various sodium intakes (52-345 mEg per day) in 30 patients with essential hypertension. The Mitral flow velocity integral in the rapid filling phase (IntR) and the atrial contraction phase (IntA) was measured from the transmitral flow pattern, and the sum of IntR and IntA (IntR + IntA), the ratio of IntA to IntR (IntA/IntR), cardiac output (CO) and total peripheral resistance (TPR) were calculated. With salt loading, the mitral flow pattern remained almost unchanged in the nonsalt-sensitive (NSS) patients. Fourteen of the 19 salt-sensitive (SS) patients showed significant increases in IntR + IntA and CO with salt loading (IntR + IntA, from 13.9 +/- 2.8 to 17.9 +/- 3.6 cm, p less than 0.01; CO, from 6021 +/- 2130 to 8305 +/- 1699 ml/min, p less than 0.01), and were termed "salt-sensitive CO-dependent" (SS [COdep]), suggesting that the apparent pressor response to sodium loading was mediated by an increased CO. In the remaining five SS patients termed "salt-sensitive CO-independent" (SS [COindep]), IntA/IntR increased significantly with sodium repletion (from 0.66 +/- 0.23 to 0.90 +/- 0.31, p less than 0.01), without a significant change in IntR + IntA. Increments in IntA/IntR observed in the SS [COindep] patients were considered to be due to an elevation of total peripheral resistance (TPR), since changes in IntA/IntR were significantly correlated with those in TPR in all subjects (r = 0.617, p less than 0.01).  相似文献   
75.
Nasal T-cell lymphoma as a type of so-called "lethal midline granuloma"   总被引:5,自引:0,他引:5  
Six cases were described in which an initial clinical diagnosis of "rhinitis gangrenosa progressiva" or lethal midline granuloma was made. The histological examinations of their surgical and autopsy specimens proved that their nasologic diseases could all be identified as malignant lymphoma arising from the nasal cavity, showing the general histologic characteristics reported for T-cell lymphomata derived from peripheral T-cells. This histologic observation was then confirmed by immunofluorescence studies using various antisera directed toward either human T- or B-cell-surface antigens. These studies clearly demonstrated that their malignant cells bore human Ly-l-like antigen but lacked human TL-like and Ia-like antigens as well as surface-bound immunoglobulins, indicating their peripheral T-cell origin. These data may suggest that so-called "rhinitis gangrenosa progressiva" or lethal midline granuloma contains at least two distinct disease categories, one of which is Wegener's granulomatosis, and the other of which is nasal T-cell lymphoma as described herein.  相似文献   
76.
We report a case of dysplasia of the congenital bilateral internal carotid arteries with the rete mirabile. The rete mirabile is not usually seen in the course of human growth, but it is a common finding in other mammals. Accordingly, some investigators have thought that the rete mirabile is "developmental shift". Our case has dysplasia of the bilateral internal carotid arteries (one is aplasia and the other is hypoplasia), but the patient had suffered from no ischemic symptom because her brain had been sufficiently fed by each of the rete mirabile. Angiographically, the frequency of the rete mirabile formation is about 1/10,000. There were 20 cases reported until 1997 (including our case). There were 5 cases (27.8%) with ischemic symptoms in spite of internal carotid artery dysplasia, 2 cases (11.1%) with intracerebral hemorrhage, 6 cases (33.3%) with subarachnoid hemorrhage (there were only two cases with aneurysm) and 5 cases without symptoms. We have tried to class the rete mirabile by angiographical findings. One is the M type finding resembling moyamoya vessels in stages 3 & 4 of moyamoya disease, and the other is the N type finding resembling a nidus of arteriovenous malformation. M type occurred in younger patients more often than N type, so M type may be the previous stage of N type.  相似文献   
77.
It is well known that urethane is a suitable anesthetic for acute studies and has been extensively recommended for investigations related to micturition physiology. This is mainly because of the capability of urethane anesthesia to spare reflex micturition as well as its easily established long-lasting and stable anesthetic level. However, urethane anesthesia is usually restricted to acute experiments due to its potential toxicity. This study searched for an alternative to urethane that would be suitable for studies in which recovery from anesthesia was needed. The list of administered drugs was as follows: pentobarbital, thiobutabarbital, ketamine-acepromazine, ketamine-diazepam, tiletamine-zolazepam, fentanyl-droperidol, alphaxalone-alphadolone, propofol, isoflurane, methoxyflurane, azaperone, tribromoethanol, and buprenorphine. Among these drugs, only tiletamine-zolazepam spared the reflex micturition contractions. However, the duration of this anesthesia was too short (approximately 30 minutes) to complete the necessary testing and additional dosing of the anesthetic generally obliterated the micturition reflex. On the other hand, rats given i.v. urethane infusion (10% solution in 0.9% saline, 3.2-4.0 mg/kg/min, total dose 0.56-1.03 g/kg) maintained a stable anesthesia that permitted both reflex micturition and stereotaxic procedures. Rats moved spontaneously 3-16 hours after cessation of i.v. urethane anesthesia and completely recovered in 2 days without significant after-effects. Bladder function was normal. No pathological changes were seen 1 week later. The present results suggest that urethane is the most suitable anesthetic for acute and chronic physiological experiments that require demonstration of reflex micturition. Neurourol. Urodynam. 19:87-99, 2000.  相似文献   
78.
OBJECTIVES: To assess visual inspection with acetic acid (VIA) as a screening tool for use in a well-equipped health center in Peru, to evaluate VIA as an alternative or adjunct to the Papanicolaou (Pap) smear, and to determine if VIA can play a role in settings other than low-resource ones. METHODS: This was a prospective study of 1 921 asymptomatic women living in Lima, Peru, carried out in 1999 and 2000. The study was performed at a cancer center equipped with the latest-generation technology and highly trained oncologists. The women underwent a complete clinical evaluation, including a Pap smear and VIA. Participants with any positive test were referred for colposcopy and biopsy. RESULTS: More women tested positive by VIA than on the Pap smear (6.9% vs. 4.2%; P = 0.0001). There were 35 women with histologic cervical intraepithelial neoplasia grade 1 (CIN 1); of these, 15 were detected by Pap and 20 by VIA (P = 0.4). A diagnosis of CIN 2 or 3 (CIN 2-3) was confirmed in a total of 13 cases; Pap detected 5 of the cases and VIA 11 of the cases (P = 0.06). The positive predictive value for detection of CIN 2+ was 8.3% for VIA and 6.3% for Pap (P = 0.5). Most importantly, while only 2.3% of patients with a positive VIA were lost to follow-up before colposcopy, that was true for 26.3% of the women with a positive Pap smear (P < 0.0001). CONCLUSIONS: VIA is useful for detection of precursor lesions of cervical cancer not only in low-resource settings but also in well-equipped health centers and cancer centers. In these non-low-resource settings, VIA has a positive predictive value comparable to the conventional Pap smear, but it is more likely to achieve earlier diagnosis, follow-up, and treatment than cytology-based screening.  相似文献   
79.
80.
OBJECTIVE: Transesophageal echocardiography was applied to visualizing endovascular procedures during transaortic stent grafting for aneurysm and dissection at the distal arch, and the use of transesophageal echocardiography was evaluated. METHODS: The 16 consecutive patients (13 with aneurysms and 3 with dissections) were examined. Transesophageal echocardiography was used for (1) determining graft size, (2) guiding placement of the catheter in the descending aorta at an appropriate position without intimal damage, (3) guiding graft tailoring with a balloon catheter, and (4) examining the results after the procedures. RESULTS: Visualization was disturbed in one patient who had undergone a previous operation. The graft size was appropriate, except in one patient as a result of underestimation. Transesophageal echocardiography was helpful for navigating the graft placement and tailoring without intimal damage. We tried to keep a distance from the diaphragm of 9 cm and an attachment portion of 4 cm. In one patient the graft was placed too distally (7 cm from the diaphragm) to cover the thick atheromatous plaque with the graft. The patient had paraplegia. Transesophageal echocardiographic assessment of endoleak and thromboexclusion was identical to that of postoperative computed tomography or angiography, with a sensitivity of 100% (1/1) and a specificity of 100% (13/13). Leakage at the proximal suture and graft kinking were found in 3 patients. Successful thromboexclusion by transesophageal echocardiographic assessment (13 patients) was predictive of subsequent regression of aneurysm and dissection in the midterm follow-up period: there was complete and partial regression in 5 and 8 patients, respectively. CONCLUSION: Transesophageal echocardiography enables echocardiography-assisted operations with secure step-by-step endoluminal procedures and immediate intraoperative assessment, which is predictive of the postoperative results.  相似文献   
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