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41.
OBJECTIVE: To conceptualize, with fine needle aspiration cytology (FNAC), the early cellular events occurring in and around fresh autogenous and allogenic bone grafts during the first 40 postimplantation days. STUDY DESIGN: Forty-eight cases of bone grafts were studied by FNAC at serial intervals of 10, 20, 30 and 40 postimplantation days. Twenty patients were recipients of autogenous grafts, 16 received 0.6N HCI partially decalcified allogenic bone implants, and 4 received combined autogenous and allogenic bone grafts (included in the allograft group). There were eight control cases of closed fracture shaft femur, which were managed conservatively. RESULTS: The initial cellular responses in autogenous grafts, allografts and controls appear to be a part of the nonspecific reparative process followed by a more specific phase, with a steady increase in relative lymphocyte count from the 20th day onwards. Osteogenesis, as judged by osteoblasts and osteoclasts, was also comparable. CONCLUSION: Partially decalcified allografts appear to be a good substitute for autogenous bone grafts in clinical practice when adequate autogenous material is not available. FNAC is a good technique for studying bone graft responses without interfering with graft uptake. It is helpful in the early detection of subclinical infection or any other pathology at the graft site.  相似文献   
42.
T cell cytokines play an important role in mediating airway inflammation in asthma. The predominance of a Th2 cytokine profile, particularly interleukin (IL)-4 and IL-5, is associated with the pathogenesis and course of asthma. The aim of this study was to test the hypothesis that a stressful life event alters the pattern of cytokine release in asthmatic individuals. Thirteen healthy controls and 21 asthmatic adolescents gave blood samples three times over a semester: midsemester, during the week of final examinations, and 2-3 weeks after examinations. Interferon-gamma (IFN-gamma), IL-2, IL-4, and IL-5 were measured from supernatants of cells stimulated with PHA/PMA for 24 h. Cells from asthmatic subjects released significantly more IL-5 during the examination and postexamination periods, whereas cells from healthy controls released significantly more IL-2 during the midsemester and examination periods, thereby indicating a bias for a Th2-like pattern in asthmatics and a Th1-like pattern in healthy controls. IL-4 and IL-5 production showed a marked decrease during and after examinations in healthy controls, whereas this decline was absent in asthmatics. The ratios of IFN-gamma:IL-4 and IFN-gamma:IL-5 also revealed significant changes in the profile of cytokine release across the semester. These results indicate differential cytokine responses in asthmatics that may become pronounced during periods of cellular activation.  相似文献   
43.
DK Veronikis  DH Nichols  MM Wakamatsu 《Canadian Metallurgical Quarterly》1997,177(6):1305-13; discussion 1313-4
OBJECTIVE: Our aims were to compare several prolapse-reducing techniques during urodynamic evaluation and prospectively evaluate their usefulness in identifying the incidence of low urethral closure pressure in continent patients with massive prolapse. STUDY DESIGN: This preoperative, prospective, repeated-measures urodynamic study evaluated the maximum urethral closure pressure with the use of four different techniques in 30 consecutive continent patients with grade 4 prolapse at all vaginal sites. Twenty patients with grade 0 prolapse served as the control group. All patients from the prolapse group underwent surgical treatment and were followed up clinically for a minimum of 1 year. RESULTS: Use of the Scopette (Birchwood Laboratories, Eden Prairie, Minn.) reduction technique to reduce the prolapse in a linear orientation during multichannel urodynamics revealed a 56% incidence of low-pressure urethra and an overall genuine stress urinary incontinence of 83% in patients with massive pelvic organ prolapse but without clinical urinary incontinence. CONCLUSIONS: There may be an increased indication for sling urethropexy in patients with massive prolapse.  相似文献   
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In this and the following paper we have examined the kinetic and steady-state properties of macroscopic mslo Ca-activated K+ currents in order to interpret these currents in terms of the gating behavior of the mslo channel. To do so, however, it was necessary to first find conditions by which we could separate the effects that changes in Ca2+ concentration or membrane voltage have on channel permeation from the effects these stimuli have on channel gating. In this study we investigate three phenomena which are unrelated to gating but are manifest in macroscopic current records: a saturation of single channel current at high voltage, a rapid voltage-dependent Ca2+ block, and a slow voltage-dependent Ba2+ block. Where possible methods are described by which these phenomena can be separated from the effects that changes in Ca2+ concentration and membrane voltage have on channel gating. Where this is not possible, some assessment of the impact these effects have on gating parameters determined from macroscopic current measurements is provided. We have also found that without considering the effects of Ca2+ and voltage on channel permeation and block, macroscopic current measurements suggest that mslo channels do not reach the same maximum open probability at all Ca2+ concentrations. Taking into account permeation and blocking effects, however, we find that this is not the case. The maximum open probability of the mslo channel is the same or very similar over a Ca2+ concentration range spanning three orders of magnitude indicating that over this range the internal Ca2+ concentration does not limit the ability of the channel to be activated by voltage.  相似文献   
46.
Specimens of formalin-fixed, paraffin-embedded non-small-cell lung carcinomas (NSCLCs; n = 187) were analysed immunohistochemically for expression of cyclin A. The analysis was intended to determine whether cyclin A has additional prognostic value for predicting patients' survival and drug response. Of the 187 NSCLCs, 141 cases (75%) showed expression of cyclin A. Patients with cyclin A-positive carcinomas had significantly shorter median survival times than patients with cyclin A-negative carcinomas (79 vs 129 weeks, P = 0.045). Similar results were obtained with more homogeneous groups of patients: patients with only T3 tumours, patients with epidermoid carcinomas and patients with lymph node involvement. The clinical parameters (age, stage, histology, extent of tumour size, lymph node involvement) had no influence on expression of cyclin A. A direct correlation between cyclin A and the proportion of S-phase cells (P = 0.08) and an inverse relationship between cyclin A and the proportion of G0/G1-phase cells (P = 0.04) were found. Furthermore, a significant correlation between the expression of cyclin A and the response of NSCLC to doxorubicin in vitro was detected (P = 0.026).  相似文献   
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48.
Modification of arginine residues in bradykinin, [1-5]-bradykinin, splenopentin and two synthetic pentapeptides with acetylacetone (pentane-2,4-dione) significantly increases the relative abundance of sequence-specific fragment ions produced by matrix-assisted laser desorption/ionization (MALDI). The fragmentation efficiency as measured by post-source decay in a reflectron time-of-flight mass spectrometer increases by a factor of 2-3.5. Peptide bonds adjacent to modified residues are more susceptible to cleavage than in the non-derivatized peptide ions. The increased lability of these bonds gives rise to more complete sequence information. In addition, the relative abundances of sequence-specific fragment ions are enhanced. This strategy makes it possible to obtain valuable structural information from arginine-containing peptides that otherwise do not fragment well.  相似文献   
49.
A case of phlebothrombosis with recurrent pulmonary and cerebral embolism is presented which occurred in a 42 year old patient two weeks after treatment of a traumatic crural fracture despite of prophylaxis with low molecular heparin. By means of transthoracic echocardiography a large intracardiac thrombus was detected, entrapped in an patent foramen ovale (PFO) and prolapsing through both atrioventricular valves into both ventricles. This was found after systemic thrombolysis with rtPA had been performed because of fulminant pulmonary embolism. Subsequently the intracardiac thrombus was surgically removed and the PFO closed. The importance of an PFO for paradoxical embolism is discussed as well as the various therapeutical paths to treat an "embolus-in-transit" (cardiac surgery, thrombolytic therapy or anti-coagulation).  相似文献   
50.
Videolaparoscopic cholecystectomy is considered the treatment of choice for simple cholelithiasis. Now many surgeons consider the laparscopic procedure usable also in the complicated biliary lithiasis like acute cholecystitis and choledocholithiasis. The authors report their recent experience of the laparoscopic treatment of biliary lithiasis, regarding 221 non-selected patients (69% symptomatic cholelithiasis, 20% chronic cholecystitis, 4.5% acute cholecystitis, 4.5% coledocolithiasis, 2% hydrops). The diagnostic-therapeutic protocol and the results are described and compared with the beginning of their experience, when they treated only symptomatic gallbladder stone disease, and with the reports of the literature. The authors concluded that the laparoscopic procedure is a good chance for the surgeon in the treatment of all cases of benign biliary disease. But, in particular for patients with choledocholithiasis, he has be able to know all the diagnostic and therapeutic possibilities, to choose the best in every single case.  相似文献   
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