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1.
In 1995, the National League for Nursing commissioned a Panel on Interdisciplinary/Transdisciplinary Education. The focus of the Panel's work was to examine educational issues that transcend the health professions and to make recommendations for future implementation of an interdisciplinary approach to addressing them. This article is being simultaneously published by several professional journals. The goal is to seek as much feedback as possible.  相似文献   
2.
Analysis of the DNA content of various solid tumors and hematological malignancies may provide useful prognostic information. To date, however, there has been a striking lack of correlation between DNA content in neoplasms of the central nervous system and clinical behavior. Simultaneous quantitation of DNA content and proliferation-associated nuclear antigen (p105) by flow cytometry was performed on paraffin-embedded tissues representing three major groups of central nervous system neoplasms--1) 21 astrocytic tumors, 2) 13 pituitary tumors, and 3) 19 meningiomas--and the results were correlated with clinical behavior. All 4 well-differentiated gliomas were diploid, while 3 of 9 anaplastic astrocytomas and 1 of 8 glioblastomas had a demonstrable aneuploid peak. Three of 13 pituitary tumors had an identifiable aneuploid peak, while only 2 of 19 meningiomas had an aneuploid DNA content. Cell-cycle analysis of the malignant gliomas revealed a significantly higher proliferative index (PI, %S + G2M) compared with the well-differentiated astrocytomas (P less than 0.05). Within the subgroup of diploid anaplastic astrocytomas, however, extended patient survival appeared to be associated with a higher PI. For diploid pituitary adenomas, the PI was consistently lower in the 3 tumors that recurred than it was in the remaining 8 adenomas. Nuclear antigen quantitation of diploid tumors showed a wide range of p105 expression in G0G1 cells, suggesting that, within each tumor, the cells are heterogeneous with respect to proliferative activity. Aneuploid nuclei of glial tumors showed enhanced expression of p105 relative to diploid cells of the same specimen. In pituitary tumors, the median G2M/G0G1 fluorescence ratio for p105 was significantly higher (P less than 0.05) for the 3 diploid recurrent tumors than for those that did not recur. These data support the assumption that the aggressive clinical course of malignant glial neoplasms may be related to an abnormal DNA stemline and/or an alteration in cell proliferative activity. Cell cycle analysis and measurement of p105 by this technique may provide information useful from both a prognostic standpoint and in directing adjuvant therapy.  相似文献   
3.
4.
Rete testis fluid (RTF) and luminal fluid collected by micropuncture at selected epididymal sites were analyzed to characterize the spectrum of proteins and to quantify the net gain or loss of total/bulk protein and androgen-binding protein (ABP) between successive regions within the ductus epididymidis. Based on one-dimensional SDS gel electrophoresis, the spectra of proteins in RTF and fluids from the proximal, central, and distal caput through proximal corpus epididymidis differed from each other. Concentrations of sperm, bulk protein, and ABP increased from the rete testis through the central caput epididymidis. Electron microscopic studies following intraluminal microinjections of RTF proteins conjugated to colloidal gold at specific sites in the excurrent ducts revealed that 145 times more protein-gold was endocytosed in the ductuli efferentes than in any of the four regions of the caput epididymidis. Thus, ductuli efferentes were the major extra-testicular site of endocytosis of bulk protein present in RTF; at least a portion of the uptake was specific. On a per sperm basis, the amount of protein present in the central caput epididymidis was less than 15% of that leaving the testis. Although most of the protein present in RTF (greater than or equal to 86 mg/d) must be absorbed in the ductuli efferentes and the initial segment of the epididymis and replaced by newly secreted proteins (greater than or equal to 34 mg/d), there was negligible loss of ABP in these regions. Net loss of ABP occurred primarily in the distal caput and proximal corpus epididymidis. These studies demonstrate that ABP is spared from endocytosis along with the bulk protein in RTF and conserved for functions in epididymal regions far distal to the site of bulk protein loss.  相似文献   
5.
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.  相似文献   
6.
Mediators of pulmonary injury induced by inhalation of bacterial endotoxin   总被引:4,自引:0,他引:4  
The purpose of this study has been to further define the pathophysiologic aspects of lung injury caused by the inhalation of endotoxin (LPS) using the morphometric approach to identify mediators that influence distal lung structure and function. Hamsters were divided into 3 groups 24 h prior to low dose LPS inhalation exposure (4 micrograms/m3 for 5 h): (1) pretreated with cobra venom factor to deplete complement in vivo, (2) pretreated with indomethacin to block prostaglandin production, and (3) untreated control group. Both pretreatments abolished LPS-induced decreases in lung volume as well as increases in capillary PMN and platelets seen in untreated control animals. Neither pretreatment had any effect on the LPS-induced decreases of other capillary leukocytes. Similarly, both methods of pretreatment failed to block increases in cellular interstitium of distal capillary septa induced with LPS alone. LPS provoked changes in capillary endothelium, especially seen as an increase in numerical density of endothelial pinocytotic vesicles. Decomplementation failed to alter this increase, but indomethacin pretreatment blocked the effect. Neither treatment had any effect on their size. Low dose LPS inhalation also altered pulmonary capillary permeability to a 125I-BSA probe, which was found in significantly greater amounts in LPS-exposed lungs than in those of saline aerosol control lungs, but was not present in the air space as evidenced by negligible counts in bronchoalveolar lavages. It is evident that endotoxin on the epithelial side of the air-blood barrier leads to changes on the other side of that barrier.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
Isokinetic, shoulder rotational strength was evaluated in 26 high school baseball pitchers before the start of spring practice. Using the Cybex II (Cybex, Division of Lumex, Inc., Ronkonkoma, NY), test data were gathered on the dominant and nondominant shoulders in the supine 90 degrees abducted test position (90 degrees AbTP) and the standing neutral test position (neutral TP). Tests were performed at 90 and 240 deg/sec. The HUMAC (Computer Sports Medicine, Inc., Flemington, NJ) computer system was used to analyze data. Means and standard deviations for peak torque, total work, peak torque to body weight ratios, and agonist/antagonist ratios are presented. Comparison of dominant to non-dominant sides and 90 degrees AbTP to neutral TP values are reported. Peak torque and total work values for the throwing side internal rotators were significantly higher than the nonthrowing side in all tests. Pitching side external rotators failed to show this dominance. External/internal rotation ratios for peak torque and total work were significantly lower on the pitching side, suggesting a relative imbalance of cuff musculature compared to the nonpitching shoulder. Significant differences existed between data gathered in the two different test positions. In the 90 degrees AbTP, external rotation peak torque and total work values and external/internal rotation peak torque and total work ratios were higher than the equivalent values gathered in the neutral TP. Internal rotation peak torque and total work values tended to be higher in the neutral TP than in the 90 degrees AbTP.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
Development of a new wound dressing with antimicrobial delivery capability   总被引:1,自引:0,他引:1  
A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved.  相似文献   
9.
The use of self-expanding prostheses in the management of malignant oesophageal strictures has become well established. The majority of benign peptic oesophageal strictures can be successfully managed using endoscopic or fluoroscopically guided balloon oesophageal dilatation combined with long-term drug therapy, particularly using proton pumper inhibitors. Although endoscopic oesophageal dilatation can be performed on an outpatient basis, it requires repeated hospital visits. There is a small risk of oesophageal perforation whilst cardio-respiratory complications may be encountered during the use of intravenous sedation in an elderly population. The use of a self-expanding Strecker stent in a 98 year old woman with a benign oesophageal stricture is described.  相似文献   
10.
Infectious intracavernous carotid artery aneurysms usually present with ophthalmoplegia and/or signs of cavernous sinus thrombosis. We report an unusual case in which a patient with AIDS presented with intractable epistaxis secondary to rupture of a giant infectious intra-cavernous carotid artery aneurysm. Culture of the aneurysm grew mycobacterium avium intracellulare (MAI). The patient was treated successfully by excision of the aneurysm and reconstruction of the internal carotid artery with a saphenous vein interposition graft.  相似文献   
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