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151.

Background

Long-term pitching activities change the stress distribution across the elbow joint surface in living subjects, however the influence of the different strength of stress on the stress distribution patterns remain unclear. The aims of this study were to evaluate the distribution of subchondral bone density across the elbow joint in different levels of pitchers, and to reveal the influence of the strength of stress on the elbow joint surface under long-term loading conditions of baseball pitching.

Methods

The current analysis was performed using computed tomography (CT) image data obtained from the throwing side elbow of 12 nonthrowing athletes (controls), 15 college baseball pitchers (college group) and 13 professional baseball pitchers (professional group). The distribution patterns of subchondral bone density through the articular surface of the elbow joints were assessed using a CT osteoabsorptiometry method. The quantitative analysis was based on location and percentages of high-density area on the articular surface.

Results

High-density area in the college and professional groups were found in the anterior part of the captellum, posterior part of the trochlea and radial head. In the professional group, the percentages of high-density area in the anterior part of the capitellum, posterior part of the trochlea, radial head and olecranon were significantly greater than in the college group.

Conclusions

Stress distribution on the articular surface of the elbow joint was affected by pitching abilities or competitive levels. Our analysis indicates that high strength of stress in professional baseball players produce potential risk of elbow injuries.  相似文献   
152.
Amyloid depositions of pancreatic islets were investigated with electron microscopy in a case of type III glycogenosis.

Beta cells adjoining small amyloid depositions were shown to have cytoplasmic invaginations where closely packed amyloid fibrils were disclosed regularly orientated amyloid bundles. In the cytoplasm of the beta cells, some membrane-bounded vesicles contained amyloid fibrils and a few beta granules directly transformed into the fibrils within the vesicles.

These findings indicate that, at least in this case, the beta cells play a crucial role in the formation of insular amyloid.  相似文献   
153.
154.
Using the mouse interleukin 3 (IL-3) receptor cDNA as a probe, we obtained a homologous cDNA (KH97) from a cDNA library of a human hemopoietic cell line, TF-1. The protein encoded by the KH97 cDNA has 56% amino acid sequence identity with the mouse IL-3 receptor and retains features common to the family of cytokine receptors. Fibroblasts transfected with the KH97 cDNA expressed a protein of 120 kDa but did not bind any human cytokines, including IL-3 and granulocyte-macrophage colony-stimulating factor (GM-CSF). Interestingly, cotransfection of cDNAs for KH97 and the low-affinity human GM-CSF receptor in fibroblasts resulted in formation of a high-affinity receptor for GM-CSF. The dissociation rate of GM-CSF from the reconstituted high-affinity receptor was slower than that from the low-affinity site, whereas the association rate was unchanged. Cross-linking of 125I-labeled GM-CSF to fibroblasts cotransfected with both cDNAs revealed the same cross-linking patterns as in TF-1 cells--i.e., two major proteins of 80 and 120 kDa which correspond to the low-affinity GM-CSF receptor and the KH97 protein, respectively. These results indicate that the high-affinity GM-CSF receptor is composed of at least two components in a manner analogous to the IL-2 receptor. We therefore propose to designate the low-affinity GM-CSF receptor and the KH97 protein as the alpha and beta subunits of the GM-CSF receptor, respectively.  相似文献   
155.
The role of the renin-angiotensin system in blood pressure control and in the development of hypertension was investigated by generating transgenic mice carrying the rat renin or angiotensinogen gene or both genes under the control of the mouse metallothionein I promoter. The systolic blood pressure was significantly elevated in transgenic mice carrying both transgenes but was maintained normally in those bearing either of the transgenes. The transgene was effectively and properly transcribed to form the mature mRNA in the transgenic mice. The production of rat renin and angiotensinogen in the transgenic mice carrying the corresponding transgene was also verified by immunoanalyses of these proteins. Furthermore, the specific angiotensin-converting enzyme inhibitor captopril was effective in reducing the elevated blood pressure of the hypertensive transgenic mice. These results indicate that the combined action of the exogenous rat renin and angiotensinogen is responsible and necessary for elevation of blood pressure in the hypertensive transgenic mice.  相似文献   
156.
To evaluate the clinical significance of simple heart rate-adjusted ST segment depression (delta ST/delta HR) in the diagnosis of coronary artery disease, 42 patients with stable exertional angina underwent supine leg exercise testing and cardiac catheterization. During exercise, heart rate, a multilead electrocardiogram, and pulmonary artery wedge pressure were recorded. The sensitivity and accuracy of the delta ST/delta HR criteria (greater than or equal to 3.0 microV/beat/min) were significantly greater than the conventional analysis of ST segment depression criteria (greater than or equal to 0.2 mV) for detecting three-vessel coronary artery disease at a matched specificity of 72% (100% versus 46%, 81% versus 64%, p less than 0.01). A significant linear correlation was found between maximum pulmonary artery wedge pressure increments during exercise (delta PAWP) or Gensini score and the delta ST/delta HR (delta PAWP: r = 0.51, p less than 0.001; Gensini score: r = 0.47, p less than 0.001). There were no statistically significant differences in the delta PAWP or Gensini score between patients with three-vessel disease who had delta ST/delta HR greater than or equal to 3.0 microV/beat/min and those with one- or two-vessel disease who had delta ST/delta HR greater than or equal to 3.0 microV/beat/min (delta PAWP: 18.1 +/- 2.0 versus 21.9 +/- 3.3, p = NS; Gensini score: 68.5 +/- 6.6 versus 66.3 +/- 11.3, p = NS). These findings demonstrate that delta ST/delta HR is more useful than a conventional analysis of ST segment depression for identifying not only anatomically severe coronary artery disease but also functionally severe coronary artery disease.  相似文献   
157.
Hypergammaglobulinemia is a frequent complication of tuberculosis. Serum levels of each class of immunoglobulin were analyzed among tuberculosis patients. Adult patients had high levels of IgG and IgA, but IgM levels were not elevated. These data suggested that antibody responses to mycobacterial antigens might be influenced by individual immune responses. In order to analyze the specific antibody responses to mycobacterial antigens, IgG class antibodies reactive with BCG proteins were enumerated by an enzyme-linked immunosorbent assay (ELISA). Patients were shown to have significantly higher a mount of IgG antibodies than healthy controls. Sera from patients with active tuberculosis had high consistently titers of antibodies. Antibody titers returned to a normal range after effective treatment, suggesting that the measurement of IgG anti-BCG antibodies would be useful for the diagnosis and follow-up of tuberculosis. In addition, serum antibody profiles were analyzed by immunoblotting. Sonicated whole BCG proteins were electrophorased and transferred to nylon sheets by Western blotting. Then the sheets were developed with sera from patients or controls. Mycobacterial cell wall contains a vast array of proteins so that comparison of the antibody profiles from different sera revealed striking individual variations. However two kinds of proteins, whose molecular sizes were 65KDa and 16KDa, were considered to be significant. The 65 KDa protein was recognized in most sera from both patients and controls. The protein may be related to a "common antigen" present in a wide variety of bacteria. These observations may shed a new light on the role of 65KDa protein in the regulation of the immune systems, for example a individual highly primed to 65KDa protein may amount an exaggerated and potentially harmful response to cross-reactive antigens from other essentially non-pathogenic bacteria.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
158.
One of the great challenges in the cytodiagnosis of effusions is the distinction between reactive mesothelium/histiocytes and cancer cells. This is notably true in patients having undergone radiation and/or chemotherapy. To establish whether monoclonal antibodies (MoAbs) could be used as reliable diagnostic adjuvants, the authors retrospectively and blindly studied 60 cases diagnosed by standard cytologic criteria (malignant, benign, and equivocal), with a panel of seven readily available MoAbs (cytokeratins, vimentin, EMA, B72.3, alpha-CEA, HMFG-2, and Leu-M1) and the lectin Ulex europaeus I. All 18 (100%) malignant cases showed reactivity with EMA and HMFG, whereas 17 (95%) and 11 (61%) reacted with B72.3 and alpha-CEA, respectively. Combinations of (1) EMA + B72.3, (2) EMA + alpha-CEA, and (3) EMA + alpha-CEA + B72.3 displayed positivity in 17 (95%), 11 (61%), and 10 (56%) malignant cases, respectively. Of the 18 benign cases, 7 reacted with HMFG and 2 each with EMA and B72.3. Only one case (5.5%) reacted with both EMA and B72.3. Based on these results, the 24 equivocal cases were regrouped into 14 malignant and 10 benign cases. Follow-up effusions obtained within the ensuing three months in all these patients allowed the authors to unequivocally confirm the diagnosis in all but five. The combination of EMA and B72.3 MoAbs detected malignant cells in 95% of the cases, with a 3.5% incidence of false positive cases in this study. A panel of EMA, B72.3, and alpha-CEA MoAbs should prove the most useful and simple approach to the correct diagnosis in most questionable effusions. Some of the potential pitfalls are discussed.  相似文献   
159.
Introduction: To elucidate the mechanism of functional recovery after gradual nerve‐stretch injury, we used rats in which the femur length was increased by 15 mm at 1.5 mm/day. Methods: We performed electrophysiology, mRNA analysis of tetrodotoxin‐resistant voltage‐gated sodium channels (TTX‐R VGSCs) in dorsal root ganglia, and histology of unmyelinated sciatic nerve fibers and examined pain thresholds at 1, 10, 20, and 30 days after cessation of lengthening. Results: Electrophysiology revealed conduction block after cessation that recovered after 30 days. TTX‐R VGSC levels decreased immediately after cessation but were restored after 10 (Nav1.9) or 20 (Nav1.8) days. Histology revealed that injured unmyelinated nerve fibers regenerate 30 days after cessation. Pain threshold decreased gradually during lengthening but had not recovered to the control group level after 30 days. Conclusions: Early restoration of TTX‐R VGSC mRNA in dorsal root ganglia preceded functional recovery of stretched nerves before regeneration of injured unmyelinated nerve fibers. Muscle Nerve 50 : 425–430, 2014  相似文献   
160.
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