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排序方式: 共有493条查询结果,搜索用时 15 毫秒
1.
A central mechanism of acute baroreflex resetting in the conscious dog   总被引:1,自引:0,他引:1  
The role of the central nervous system in the mechanism(s) involved in acute carotid baroreflex resetting was studied in six conscious, chronically instrumented, aortic-denervated dogs. Dogs were prepared for reversible vascular isolation of the carotid sinuses. Acute baroreflex resetting was induced by holding the left carotid sinus pressure (LCcsp) at a given value for 20 minutes using a pulsatile pressure control system while at the same time keeping the right carotid sinus pressure (RCSP) at a subthreshold level (approximately 40 mm Hg). At the end of the 20 minutes, the LCcsp) was reduced to approximately 20 mm Hg, and a baroreflex (RCSP-mean arterial pressure [MAP]) curve was generated on the right carotid sinus using static-step increases in carotid sinus pressure. At the control LCcsp of 100 mm Hg, the RCSP-MAP baroreflex had a threshold pressure (Pth) of 86.6 +/- 3.1 mm Hg and a set point pressure (Psp) of 104.7 +/- 2.5 mm Hg. Increasing LCcsp) to 140 mm Hg for 20 minutes caused these parameters for the right carotid baroreflex to increase. Pth and Psp increased by 18.4 +/- 4.0 and 14.2 +/- 3.0 mm Hg, respectively (p less than 0.05). The baroreflex curve, therefore, was shifted upward and to the right. Decreasing LCcsp to 60 mm Hg caused Pth and Psp to decrease by 24.7 +/- 5.0 and 18.1 +/- 2 mm Hg, respectively (p less than 0.05). The baroreflex curve was therefore shift downward and to the left. The percent of resetting of Pth and Psp was 46 +/- 9% and 36 +/- 8%, respectively, when LCcsp was 140 mm Hg.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Soft tissue sarcomas of the head and neck in adults   总被引:1,自引:0,他引:1  
We reviewed the clinical records and pathologic material of 176 adults with primary soft tissue sarcomas treated at Memorial Sloan-Kettering Cancer Center between 1950 and 1985. Seventy-two patients (41%) had low-grade sarcomas and 104 (59%) had high-grade sarcomas. All but 18 patients underwent some form of excision as initial therapy. Adjuvant radiotherapy and chemotherapy combined with surgical excision showed no significant effect. A significantly increased risk of treatment failure was associated with large tumor size, positive surgical margins, bone involvement, local recurrence, metastatic spread, and high histologic grade. Except for recurrence, the p value by univariate analysis in the log-rank test for comparison of survival according to these clinical and pathologic characteristics was p less than 0.0001. Although the overall survival was 75% at 2 years, 55% at 5 years, and 46% at 10 years, only 20% of the patients with high-grade sarcomas were alive 10 years after treatment. Most patients with rhabdomyosarcoma, high-grade peripheral nerve tumor, and high-grade fibrous histiocytoma and all patients with high-grade angiosarcoma died of disease less than 5 years after diagnosis. New therapeutic strategies are needed to improve the survival of adult patients with high-grade soft tissue sarcomas of the head and neck.  相似文献   
3.
Fractures of the proximal humerus in children are rare and constitute only 3% of all epiphyseal injuries. From 1992 to 2002 sixteen patients aged 4 - 15 years with a displaced fracture of the proximal humerus were treated at our level I trauma unit. The mean follow-up of the patients was 23.8 months (8 - 72). Ten children had a metaphyseal fracture and six a Salter and Harris Type II injury. Only one metaphyseal fracture was treated conservatively; the other patients underwent surgery (ORIF [= open reduction internal fixation] in ten patients, CRIF [= closed reduction internal fixation] in five patients). Follow-up examination showed no shortening or major angulation of the humerus in any of the sixteen cases. Fifteen children showed excellent and good results. There was only one average result in a polytraumatized child with additional injuries in both upper extremities. Based on the results of this study we suggest performing ORIF/CRIF in displaced fractures of the proximal humerus in children.  相似文献   
4.
Juxtaoral organs known as organs of Chievitz are intramuscular embryonic structures found close to the angle of the mandible near the insertion of the pterygomandibular raphae. They are considered of neuroepithelial origin with no known function. We describe the first tumor of the organ of Chievitz which presented intraorally in a child. Immunohistochemically, the Chievitz nests showed positive reaction for vimentin, cytokeratins, and epithelial membrane antigen and ultrastructurally demonstrated cytoplasmic processes and intermediate filament bundles. These observations, together with light microscopic features, suggest that the epithelial nests of the organ of Chievitz are meningothelial rather than neuroepithelial. Received December 18, 1996; accepted March 13, 1997.  相似文献   
5.
Telomerase is the enzyme responsible for synthesizing telomeric repeats at the ends of chromosomes to maintain telomere length. Recent studies have suggested that telomere shortening may serve as a surrogate marker of the progression of malignant disorders and seems to be accelerated in allogeneic bone marrow transplant recipients. In this study, the results of the telomere length of nine cord blood mononuclear cell samples are presented. Telomere length was measured by the flow-FISH method, using a peptide nucleic acid probe. The proportion of cord blood cell subsets (CD19/CD34/CD3) was also evaluated. The telomere length of the internal control 1301 cell line was estimated to be 100%. The mean telomere length of cord blood cells was 18.5 +/- 3.9%, compared with the internal control. The progenitor CD34+ cells were detected as 2.6 +/- 0.7% in the lymphoid gate measured. Linear correlation analysis did not find any connection between the cell subsets (CD3+, CD34+, CD19+) and the telomere length. The findings confirm that the telomere flow-FISH method is sufficient for estimation of the telomere length. Assessment of the current procedures of collection, manipulation, and ex vivo expansion of cord blood cells in terms of their effect on telomere shortening might be important.  相似文献   
6.
Thirty-five Salmonella strains isolated from human cases of salmonellosis were tested and compared for their fibronectin (fn) binding capacities by using two fn-particle agglutination assays (fn-PAAs) prepared by coating with human fn either (i) latex beads (Difco; 0.81-micron diameter) (L-fn-PAA) or (ii) heat-killed formalin-treated Staphylococcus aureus Cowan 1 cells (C-fn-PAA). Six S. aureus strains were also included in this study as controls. The strains were cultured on colonization factor antigen agar and blood agar and in tryptic soy broth and brain heart infusion broth. The Salmonella and S. aureus strains were cultured at 33 and 37 degrees C, respectively, for optimal expression of fn-binding proteins. Bacterial cells (approximately 10(10) cells per ml) harvested from growth in various culture media and suspended in 0.02 M potassium phosphate buffer (pH 6.8) agglutinated the fn-PAA reagents. These reactions were scored semiquantitatively from + to + depending on the speed or intensity of the reactions within 2 min. Maximum agglutination in fn-PAA systems was observed when the cells were grown in brain heart infusion broth, while tryptic soy broth proved to be least suitable media for culturing cells for fn-PAAS. Although a statistically highly significant correlation was obtained between results of assays of radiolabeled fn and 29-kDa fragment binding, no significant correlation was observed (i) between the results of strains cultured in different media or (ii) when semiquantitative score results of the two fn-PAA systems were compared with those of the conventional radiolabeled fn assay. To enhance the efficiency of the test system, the C-fn-PAA reagent was stained with methylene blue (2% in 0.17 M glycine-NaOH buffer [pH 6.8]). This facilitated easy interpretation of results, which could be performed on hydrophobic paper instead of glass slides. The results obtained with both unstained C-fn-PAA and stained C-fn-PAA were comparable to each other and reproducible. Although the fn-PAAs are simple and easy to perform, the results did not differentiate between negative, low, moderate, and high binding abilities when Salmonella strains were evaluated for fn binding, and the results were not comparable to those obtained by the conventional radiolabeling method.  相似文献   
7.
Brainstem auditory evoked potentials were bilaterally normal, and somatosensory evoked potentials were unilaterally abnormal in a patient with a large pontine infarct causing a "locked-in" syndrome. In the post mortem examination, the lesion extended unilaterally into the pontine tegmentum, partially involving the left medial lemniscus. The P14 potential was absent and the N20 potential was diminished in amplitude with right median nerve stimulation. The origin of the P14 potential has been debated in the literature. This case provides evidence for the P14 generator being located at the pontine level, in relation to a lemniscal area above the decussation of the somatosensory pathway. Evoked potentials can help to determine the tegmental extension of the pontine infarcts in the "locked-in" syndrome, especially in patients unable to cooperate with clinical examination.  相似文献   
8.
More and more breast lumpectomies are being performed due to mammographic screening, and both in situ and invasive breast carcinomas are being detected earlier and smaller in size. The objective of this study was to determine the presence of incidental microscopic breast carcinoma in mammography-guided lumpectomy specimens. A prospective study was carried out by processing in surgical pathology approximately 9,000 breast lumpectomy specimens during a 2.5-yr period so that the entire specimens were embedded for microscopic examination. Excluded from the study were cases with grossly or microscopically identified carcinomas greater than 10 mm2, and non-invasive carcinomas diagnosed in association with invasive carcinoma. Cases with multifocal carcinomas, prior diagnosis of breast cancer, or prior history of breast biopsy were also excluded. Carcinomas present in the same tissue blocks as the clinically suspected lesions such as palpable nodules, microcalcification, or other mammographic abnormalities were excluded as well. Fifty cases of incidental microscopic mammary carcinoma were found including 8 infiltrating ductal carcinomas (IDC), 2 infiltrating lobular carcinomas (ILC), 21 intraductal carcinomas (DCIS), and 19 lobular carcinomas in situ (LCIS). All of the lesions were solitary, located in indistinct loosely arranged fibrous and adipose stromal tissues, and the majority of them were near or at the inked excisional margins. Physicians who care for patients with breast cancer should be aware of the existence of these minute breast carcinomas that are often near or at the surgical margins. The significance of these microscopic findings for therapeutic strategy and prognosis should be determined by long-term follow-up.  相似文献   
9.
The European Journal of Health Economics - Patient activation comprises the skills, knowledge and motivation necessary for patients’ effective contribution to their care. We adapted and...  相似文献   
10.
Avulsion fractures of the tibial apophysis are rare. Seven cases were treated between 1993 and 1998 in our department. The treatment was conservative in 1 case, in the other 6 open reduction and internal fixation was used. The results after an average of 23 months were good. There were no growth disturbances.
Résumé  L’avulsion fracture de l’apophyse tibiale est rare. Sept cas ont été traités entre 1993 et 1998. Dans un cas le traitement était conservateur. Dans les autres cas, une réduction ouverte avec fixation interne a été utilisée. Les résultats après une moyenne de 23 mois étaient bons. Il n’y avait pas de trouble de la croissance.


Accepted: 12 May 2000  相似文献   
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