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1.
Underlining the importance of Profundus Femoral Artery and its capacity to make up for lower limb's haemodynamics during obliterative arteriopathy, the Authors conceive a funnel-shaped intravascular prosthesis, Goretex constructed (PTFE), to introduce, in case of obstruction, in the artery lumen with a suitable instrument. The research is performed through ten oldster dogs whose average weight is twenty-four kilograms. Isolated the deep Femoral Artery and carried out an arteriotomy of about two centimetres on the Common Femoral Artery, we bring the prothesis in Profundis Femoral Artery and we fix it to the wall of the Common Femoral Artery with 8/O microsurgical dots. After thirty days, the arteriographic test shows the patency of the endoprosthesis with normal peripheral flow in nine animals out of ten. By virtue of this preliminary experiment, the Authors point out the semplicity of this intervention, also feasible in local anaesthesia, the good tolerability of the prosthesis and its perfect integration with the surrounding arterious wall, without shifts or dissecting laminar flows between the external prosthesis wall and the vessel lumen of the animal.  相似文献   
2.
Demonstration of malignant cells in blood specimens collected during transurethral resection of the prostate (TURP) has implicated TURP in the dissemination of prostatic cancer. Of 153 patients who underwent radiation therapy for prostate cancer between January 1977 and June 1990 and were retrospectively analyzed, 93 were evaluable. Fifty-nine patients required TURP before radiation therapy for prostatic obstruction (BPH and/or cancer); the remaining 34 patients underwent radiation therapy after fine-needle aspiration biopsy. No statistically significant difference in failure rate could be detected between these groups, with a failure rate of 47% (28 of 59 patients) at a median follow-up time of 49 months (range, 8 to 146 months) in the TURP group versus a failure rate of 47% (16 of 34 patients) at a median follow-up time of 50 months (range, 3 to 122 months) in the group who underwent biopsy only (Fisher's exact test, P = 0.23). Within the confines of this retrospective study, it appeared that TURP did not enhance the development of metastatic disease.  相似文献   
3.
Given current clinical use of phospholipid bilayer structures (liposomes/vesicles) as nontoxic drug delivery vehicles, we have addressed the possibility of employing the phospholipids themselves as MRI contrast agents. To this end we have synthesized phosphatidylcholine with a nitroxide spin label replacing one methyl residue of the choline headgroup. This material was mixed with natural phosphatidylcholine in mole ratios from 1:50 to 1:1 and used to prepare sonicated unilamellar vesicles in saline. Expected structural features of these vesicles were verified by freeze-fracture electron microscopy. Proton T1 values of saline were readily decreased to less than 0.3 s by such preparations, yielding a net relaxivity of 0.6 M-1 s-1. The approach seems to be a realistic way of firmly associating a contrast agent of minimal toxicity with ordinary liposomes/vesicles in a manner that is not subject to leakage.  相似文献   
4.
The kinetics of activation and induction of several effector functions of human natural killer (NK) cells in response to Mycobacterium bovis bacille Calmette-Guérin (BCG) were investigated. Owing to the central role of monocytes/macrophages (MM) in the initiation and maintenance of the immune response to pathogens, two different experimental culture conditions were analysed. In the first, monocyte-depleted nylon wool non-adherent (NW) cells from healthy donors were stimulated with autologous MM preinfected with BCG (intracellular BCG). In the second, the NW cells were directly incubated with BCG, which was therefore extracellular. In the presence of MM, CD4+ T lymphocytes were the cell subset mainly expressing the activation marker, CD25, and proliferating with a peak after 7 days of culture. In contrast, in response to extracellular BCG, the peak of the proliferative response was observed after 6 days of stimulation, and CD56+ CD3- cells (NK cells) were the cell subset preferentially involved. Such proliferation of NK cells did not require a prior sensitization to mycobacterial antigens, and appeared to be dependent upon contact between cell populations and bacteria. Following stimulation with extracellular BCG, the majority of interferon-gamma (IFN-gamma)-producing cells were NK cells, with a peak IFN-gamma production at 24-30 hr. Interleukin (IL)-2 and IL-4 were not detectable in NK cells or in CD3+ T lymphocytes at any time tested. IL-12 was not detectable in the culture supernatant of NW cells stimulated with extracellular BCG. Compared to the non-stimulated NW cells, the NW cells incubated for 16-20 hr with BCG induced the highest levels of expression of apoptotic/death marker on the NK-sensitive K562 cell line. BCG also induced expression of the activation marker, CD25, and proliferation, IFN-gamma production and cytotoxic activity, on negatively selected CD56+ CD3- cells. Altogether, the results of this study demonstrate that extracellular mycobacteria activate several NK-cell functions and suggest a possible alternative mechanism of NK-cell activation as the first line of defence against mycobacterial infections.  相似文献   
5.
Summary Extracellular single-neuron recordings were obtained from electrophysiologically identified nigrostriatal neurons in chloral hydrate anesthetized rats, in order to test the hypothesis that excitatory amino acid receptors are involved in responses of these neurons to electrical stimulation of the pontine region where the pedunculopontine nucleus (PPN) is located. The effects of iontophoretic application of excitatory amino acids and their antagonists as well as of cholinergic antagonists were tested on the fast orthodromic excitation of nigrostriatal neurons evoked by stimulation of the PPN region. The N-methyl-D-aspartate (NMDA) receptor antagonist D-a-aminoadipic acid as well as the cholinergic receptor antagonists mecamylamine and atropine failed to suppress the synaptic excitation of nigral neurons. The NMDA receptor antagonist DL-2-amino-5-phosphonovalerate exerted a weak depressant action on the synaptic response in a few neurons only. On the contrary, the broad spectrum antagonists of excitatory amino acid receptors kynurenic acid and gamma-Dglutamyl-amino-methyl-sulphonate were found to block simultaneously both the synaptic excitation and the neuronal responses to iontophoretic pulses of glutamate while leaving unaffected the neuronal responses to local application of acetylcholine or carbachol. The competitive antagonist of non-NMDA receptors 6-cyano-2,3-dihy-droxy-7-nitro-quinoxaline suppressed the synaptic excitation at ejection currents which antagonized neuronal responses to quisqualate and kainate. These results suggest that PPN excitatory fibers synapsing onto pars compacta nigrostriatal neurons utilize an excitatory amino acid as a synaptic transmitter acting preferentially on non-NMDA receptors.  相似文献   
6.
7.
BACKGROUND: Serotoninergic (5-HT) neurons are suggested to regulate estrous cycle in animal models. In the present study we evaluated whether a relationship exists between the serotoninergic precursors in the central nervous system and the gonadotrophin-ovarian cyclic function. METHODS: We measured 5-HT precursors [free (FT) and total (TT) tryptophan] and LH, FSH and 17beta-estradiol (E2) levels in the serum of 15 fertile women with normal menstrual cycles during the follicular (cycle days 1-5, 7-11), mid-cycle (cycle days 14-16) and luteal (cycle days 17-19, 22-24) phases. RESULTS: TT and FT were significantly increased in the 7-11 and 17-19 cycle days and were decreased at mid-cycle (P < 0.01), with a cyclic and opposite behaviour when compared to that of FSH and LH. Indeed, correlation analysis through the matrix of mean values showed that LH was negatively correlated to TT (r = -0.636) and FT (r = -0.574), as well as FSH (TT, r = -0.655; FT, r = -0.663), and that TT and FT were positively correlated to each other (r = 0.801; P < 0.001). Furthermore, whilst the two FT peaks reached approximately the same levels in the follicular and luteal phase, TT levels were approximately 30% higher in the luteal than in the follicular phase of the cycle: thus in the first (follicular) phase FT peak was relatively higher than that of TT, whereas the contrary occurred in the second (luteal) phase of the cycle. CONCLUSIONS: Both TT and FT levels have cyclic variations throughout the menstrual cycle, being lowest at mid-cycle (14-16 cycle days), concomitant with the highest LH and FSH concentrations, and higher before and after mid-cycle phase, coinciding with the lowest circulating LH/FSH levels. Since TT and FT levels in the plasma have cyclic changes, our study: (i) suggests that a consumption of serum serotonin precursors takes place concomitant with gonadotrophin release during menstrual cycle; (ii) may represent an in vivo model to investigate this relationship in women in different physiopathological conditions.  相似文献   
8.
A new technique which allows lymphocytapheresis to be combined with cascade filtration (CF) is described in this paper. This therapeutical approach was applied for the treatment of patients affected by necrotizing vasculitis (1), inflammatory myopathies (5), Cryoglobulinemia (5), immune complex polyneuropathies (7), rheumatoid arthritis (3) and psoriasis (3 patients). Two cases of Waldenstrom's macroglobulinemia were also treated after the onset of the hyperviscosity syndrome. 78 procedures have been performed without any untoward effect. From a clinical point of view all patients had some improvement following treatment, thereby confirming not only the clinical safety of this therapeutical approach but also its effectiveness at least in the management of diseases which usually respond to plasma exchange treatment. Laboratory investigations showed that with CF it is possible to selectively remove IgM, immune complexes, fibrinogen, lipoproteins and high molecular weight plasma components, sparing most albumin and IgG globulins (85 and 71%, respectively).  相似文献   
9.
The prevalence of methicillin-resistant and multiply antibiotic-resistant staphylococci causing infections in hospitalized patients was studied over a two-year period. Among 122 clinically significant staphylococci, the prevalence of methicillin resistance was 66 %, with a higher prevalence ofStaphyloccus haemolyticus (85 %) andStaphylococcus epidermidis (83 %) observed than ofStaphylococcus aureus (49 %). Multiple antibiotic resistance was observed more frequently among coagulase-negative staphylococci (52 to 70 %) than amongStaphylococcus aureus (17 %). All strains of methicillin-resistantStaphylococcus aureus were susceptible to glycopeptide antibiotics and to trimethoprim-sulfamethoxazole, whereas approximately 50 % of coagulase-negative staphylococci exhibited either moderate susceptibility or resistance to teicoplanin. For these latter strains, vancomycin remains the agent of choice, whereas teicoplanin cannot be recommended unless its efficacy is established by MIC determination.  相似文献   
10.
A review of sixty-two technetium scrotal scans performed over a one-year period has led to a classification of pathologic states based on the degree of uptake of the radioactive isotope. Absent uptake, or a "cold" scan, is present only with testicular torsion, and rarely with avascular tumors. Increased uptake, or a "hot" scan, is most commonly seen with inflammatory conditions such as acute epididymitis and orchitis, and less commonly with tumor. "Mixed" scans can be associated with abscess, tumor with necrosis, trauma, and late torsion.  相似文献   
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