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61.
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Bronchocentric granulomatosis (BCG) is a rare chronic granulomatous lung disease that leads to destruction of the airway walls. It has been observed in association with various conditions, but never, so far, been reported to involve the central nervous system. We report a case of histologically confirmed pulmonary bronchocentric granulomatosis temporally associated with a partial central diabetes insipidus (CDI). Although the pathological basis of the posterior pituitary gland involvement was not ascertained, the temporal association of bronchocentric granulomatosis and central diabetes insipidus, as well as the fact that corticosteroid treatment provided stable remission of both conditions after a 10 month follow-up, strongly suggest that central diabetes insipidus was aetiologically related to bronchocentric granulomatosis in this patient.  相似文献   
63.
Expression of the Kdp system sensitizes cells to methylglyoxal (MG) whether this electrophile is added externally or is synthesized endogenously. The basis of this enhanced sensitivity is the maintenance of a higher cytoplasmic pH (pHi) in cells expressing Kdp. In such cells, MG elicits rapid cytoplasmic acidification via KefB and KefC, but the steady-state pHi attained is still too high to confer protection Lowering pHi further by incubation with acetate increases the sensitivity of cells to MG.  相似文献   
64.
The results of two previous studies have shown that implant porosity can be used to increase both the measured diffusion coefficients and the vascularity within the tissue encapsulating long-term subcutaneous implants. This study investigates the hypothesis that the analyte concentrations within the tissue surrounding porous implants will respond more quickly to changes in plasma levels than does the densely packed, avascular fibrous capsule surrounding nonporous implants. The average concentration of lissamine-rhodamine was measured in tissue within 100 microm of the following implants at four different times following injection of the tracer: PVA-skin, PVA-5, PVA-60, PVA-700 (polyvinyl alcohol nonporous, 5 microm, 60 microm, and 700 microm mean pore sizes, respectively) and PTFE-0.5 and PTFE-5 (polytetrafluoroethylene 0.5 microm and 5 microm mean pore sizes, respectively). The results were compared to those of unimplanted subcutaneous tissue (SQ). In addition, the data were analyzed with a simple two-compartment model in which a tissue response time constant (taup) was extracted. As in the case of vascular density, the cellular dimension of the PVA-60 pore sizes produced surrounding tissue with the optimum response times to changes in plasma concentrations. The concentrations of rhodamine within the tissue surrounding the PVA-60 implant were the highest at all time points and responded to the change in plasma rhodamine concentration approximately three times more quickly (taup = 764 s) than the fibrous tissue encapsulating the nonporous PVA-skin (taup = 2058 s) and more than twice as quickly as SQ (taup = 1627 s). The overall mass transfer rate between plasma and the tissue surrounding the different implants calculated from the permeability and density of vessels from the previous study correlated very well (r2 = 0.7, p < .02, slope of 0.98) with the reciprocal of the tissue response time constant (taup).  相似文献   
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The Rh50 glycoprotein is suspected of being involved in Rh antigen expression. We prepared Rh50 cDNA from a human bone marrow library by polymerase chain reaction and then subcloned this cDNA into various vectors. The vector containing Rh50 cDNA produced a 30-kDa nonglycosylated form of Rh50 in a rabbit reticulocyte lysate system and produced partially glycosylated Rh50 (32 kDa) when microsomes were added to the system. COS-1 cells transiently transfected with the vector containing Rh50 cDNA produced partially glycosylated Rh50 (32 kDa) recognized by a Rh50-specific antibody. Surface expression of Rh50 in K562 cells was also detected by flow cytometry using mouse monoclonal antibody (2D10) specific to Rh50. Partially glycosylated Rh50 (32 kDa) was again isolated from the lysates of K562 cells metabolically labeled with [35S]-methionine or [3H]-mannose using anti-Rh50 antisera. These systems (K562 and COS-1 cells) should prove useful for studying the transport of Rh proteins within the cell and the necessary components needed for Rh antigenicity at the cell surface.  相似文献   
67.
Blindness due to diabetes mellitus is potentially preventable in the majority of patient. Early detection of sight-threatening changes is associated with a better outcome, indicating the need to screen for retinopathy. At least 50% of diabetic patients do not attend a hospital, so that diabetologists and ophthalmologists are unable to screen the diabetic population comprehensively. Although in theory all patients has access to general practitioners, these may lack training or confidence to screen for retinopathy. Hospital based or community optometrists using direct ophthalmoscopy or slit lamps and technicians performing fundus photography are alternatives which may be more effective. Further studies are required to examine the effectiveness of optometry screening. Initial studies using fundus photography raised concerns about the sensitivity of the technique, but these have been partially addressed by improvements in methodology and technology. As well as technicological effectiveness, factors affecting patient uptake of screening services still need to be addressed.  相似文献   
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69.
Cultured human umbilical vein endothelial cells (HUVECs) at passage 4 specifically bound 70 +/- 12 fmol [3,5-3H]Tyr4-Ile5-angiotensin (Ang) II/mg protein, with a Kd of 0.9 +/- 0.36 nM. Binding was eliminated in cells preincubated with a monoclonal antibody (6313/G2) raised against the subtype AT1 of the Ang II receptor. Freshly seeded HUVECs were positive for 6313/G2 antibody by immunocytochemistry, and such immunoreactivity was still retained at passage 4. Incubation of HUVECs for 20 min with different concentrations of Ang II provoked a significant increment in Na+/K+ ATPase activity compared with controls, in a dose- and time-dependent manner. Maximal response was obtained with 1000 pM Ang II after 20 min stimulation and resulted in a 2.2-fold increment in Na+/K+ ATPase activity. This stimulation was abolished when cells were incubated with 1000 pM Ang II in the presence of 1 microM of the specific AT1 subtype inhibitor, DuP753. Moreover, preincubation of HUVECs with 6313/G2 or with 1 mM dithiothreitol also inhibited the stimulatory effect of Ang II. These results suggest that the AT1 receptor subtype mediates the Na+/K+ ATPase response to Ang II in these cells.  相似文献   
70.
Complement (C) is an important component of innate immunity, and was also shown recently to participate in induction of acquired B cell humoral immunity. In this study, we present evidence that C also participates in acquired T cell immunity. We found that C was involved in early events of the efferent elicitation phase of contact sensitivity (CS), and delayed-type hypersensitivity (DTH). Thus, CS and DTH were inhibited by administration of a C-blocker, soluble recombinant C receptor-1 (sCR1), when given 30 min before, but not 3 h after local antigen challenge. Among C components, local C5 were thought crucial to elicitation of CS, since local administration of anti-C5 monoclonal antibodies or locally injected C-depleting cobra venom factor also inhibited CS and DTH. These findings were consistent with our previous finding of the importance of C5 for CS elicitation, using congenitally C5-deficient mice. To dissect the mechanism of C dependence in CS, we demonstrated that locally increased early macrophage chemotactic activity (probably C5a) in evolving CS skin extracts, as well as late elaboration of IFN-gamma, were both inhibited by anti-C treatment. In addition, histological analysis showed that leukocyte recruitment into CS ear sites was similarly C-dependent. Furthermore, an initiating role of B cell-derived C-fixing immunoglobulin was suggested by demonstration of impaired CS responses in B cell-deficient mice. In summary, these results suggest that C was activated locally, perhaps via a B cell product, in an important early component of the stepwise events necessary to elicit CS, leading to local production of C5-dependent macrophage chemotactic activity and later IFN-gamma, and subsequently leading to cell infiltration, for development of T cell-dependent CS.  相似文献   
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