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101.
One hundred and one patients, nursed in an intensive care unit for at least 24h, were monitored for bacterial colonization and infection. The infection rates were similar to those in other reports. Patients were not generally colonized with common environmental strains in the unit. Bacterial dissemination between patients was uncommon. No gentamicin resistant gram negative or Staphylococcus aureus strains were observed, nor methicillin resistant Staphylococcus aureus strains. the hypothesis that these favourable conditions are partly related to the excellent isolation and barrier nursing facilities in the unit cannot be fully substantiated.  相似文献   
102.
The diagnostic significance of anticytoplasmic autoantibodies (ANCA) was studied in 71 renal patients. The ANCA test was positive in 67% of patients with Wegener's granulomatosis (WG), in 35% of those with a simultaneous renal and respiratory tract disease but not diagnosed as WG and in 22% of patients with a renal disease associated with unspecific collagenosis/vasculitis. Among WG patients ANCA positivity clearly correlated with the presence of active renal disease. Interestingly, both ANCA-positive and -negative patients were encountered in the group with acute renal failure and acute extracapillary glomerulonephritis associated with diffuse pulmonary infiltrates. The diagnostic and clinical significance of the ANCA test in these cases remains for the present obscure. In the majority of the ANCA-positive renal patients with respiratory tract abnormalities, the antibodies showed diffuse cytoplasmic staining and were mostly of the IgG class, of both IgG and IgM classes in some cases and of IgG, IgM and IgA classes in 1 patient. In patients with unspecific vasculitis/collagenosis the level of ANCA was rather low, and the distribution of different isotypes resembled that of patients with respiratory symptoms. A certain isotype of ANCA or staining pattern did not mark out any clinicopathologic subgroup among the patients. Our findings indicate that the clinical picture of ANCA-positive patients varies considerably and the ANCA test may not be as specific a marker of WG as previously suggested.  相似文献   
103.
104.
Summary Silanated slides provide excellent tissue adhesion for routine histology, immunhistochemistry and in situ hybridization of frozen, paraffin embedded material or cell smears. An easy and inexpensive method of treating glass microscope slides with triethoxysilylpropylamine is reported.  相似文献   
105.
An extrachromosomal nucleic acid element was detected in high-molecular-weight DNA preparations formBabesia equi merozoites. This extrachromosomal element was shown to be DNA rather than RNA and had an apparent fragment size of about 9 kilobasepairs (kb). Hybridization experiments using purified 9-kb DNA as a probe revealed sequence homologies with extrachromosomal DNA from two otherBabesia species.  相似文献   
106.
107.
Beta-interferon (IFN-β) is a promising treatment in multiple sclerosis (MS), reducing the exacerbation rate and MRI lesion burden, as well as the disease progression in relapsing-remitting MS. IFN-β was originally defined by its antiviral effects, but the interest has recently been focused on its immunomodulatory properties. Myelin basic protein (MBP) is one of several autoantigens considered to be the target for autoaggressive immune responses, which eventually might lead to the development of MS. To study in-vitro effects of IFN-β1b on MBP induced cytokine expression, mRNA for the Th1 cytokines IFN-γ and TNF-α, the Th2 related IL-4 and IL-6, the cytolytic perforin and the immune response downregulating TGF-β was measured with in situ hybridization after culture of blood mononuclear cells (MNC) in the presence and absence of MBP. Numbers of cells expressing IFN-γ, TNF-α, perforin and IL-4 mRNA were significantly suppressed after culture with 10 U/ml IFN-β1b. No such effect was seen on MBP induced IL-6 or TGF-β mRNA expression. These observations suggest that one of the major effects of IFN-β1b is the induction of a shift in the cytokine mRNA profile towards a more immunosuppressive pattern. In parallel in vitro tests, the control substance dexametasone (40 μg/ml) reduced the numbers of cells expressing mRNA for all cytokines under study with the exception of TGF-β, to an extent equal to or even more pronounced than IFN-β1b.  相似文献   
108.
In three groups of six mice each, the α- and β-receptors were blocked by phentolamine and propranolol. The mice in the three groups then received an intravenous bolus injection of saline solution, epinephrine, and insulin, respectively. Cortical bone capillaries from the tibia diaphysis were submitted to transmission electron microscopy (TEM). The lumen and endothelium were measured and the results compared. Significant changes were only noted in the endothelium after the administration of insulin. These findings suggest that there are also insulin receptors in bone. Furthermore, they support previous findings in similar studies with epinephrine.  相似文献   
109.
110.
The right gastroepiploic artery (GEA) was used as a pedicled conduit for direct coronary artery revascularization in 20 patients presenting with more or less exhausted saphenous vein resources. The early angiographic patency of the GEA conduit appears to be satisfactory when it is connected to the right coronary artery system. A distinct disadvantage of GEA grafting is the necessity to enter the abdominal cavity, which may lead to probably rare and as yet unrecognized morbidity. Future abdominal surgery may injure the GEA conduit unless its topographic relations to the prepyloric antrum, liver and diaphragm are properly recognized. The surgeon must then be prepared to encounter antegastric, retrogastric, antehepatic, transhepatic and retrohepatic routes of the redirected intraabdominal artery. The present paper addresses this problem. Preoperative angiography of the celiac trunk and superior mesenteric artery may be helpful in decision-making when a patient reports or records show that a graft has been harvested from the abdominal cavity.  相似文献   
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