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881.
RC Skarnes SK Brown SS Hull JA McCracken 《The Journal of experimental medicine》1981,154(4):1212-1224
Biphasic fevers were induced in sheep with intravascular infusions or injections of 4-10 μg (80-200 ng/kg) of endotoxin, whereas monophasic fevers were obtained with doses of 1-2/μg (20-40 ng/kg). A marked increase in arterial blood pressure invariably accompanied the onset of fever; the latency of responses to the higher and lower doses of endotoxins averaged 26 min and 42 min, respectively. Prostaglandin (PG) assays of plasma from the carotid artery and jugular vein during fever episodes revealed a surge of PGE and PGF coincident with the pressor response and the first phase of fever, but PG were not detected in plasma samples taken throughout the second phase of fever. PG measurements of arterial and venous plasma collected at a distal site (hind limb) showed a similar surge of PGE and PGF in association with the early fever response, indicating that intravascular PG synthesis and release represents a generalized systemic response to circulating endotoxin. Carotid arterial infusions of PGE(2) produced immediate monophasic fevers and pressor responses, whereas PGD(2) infusions produced an immediate pressor effect but no fever. Infusions of PGF(2α) or prostacyclin, however, evoked neither fever nor pressor effects. Intracarotid infusions of leukocyte pyrogen (LP) caused monophasic fevers with latent periods of 15-20 min but pressor responses were not seen and neither PGE nor PGF were detected in plasma samples from the carotid artery or jugular vein before or during fever. Indomethacin, a potent inhibitor of arachidonic acid metabolism, blocked fever responses to endotoxin and to LP. These findings implicate PGE as the mediator of the early phase of endotoxin fever and imply a role for another pyrogenic metabolite ofarachidonic acid in the mediation of the second phase of fever, i.e., the phase associated with circulating LP. It is possible that both pyrogenic metabolites are generated within the vascular compartment, reaching thermoregulatory centers of the brain by transfer across the blood-brain interface. 相似文献
882.
DF Stroncek ; SK Fautsch ; LC Lasky ; DD Hurd ; NK Ramsay ; J McCullough 《Transfusion》1991,31(6):521-526
Marrow is cryopreserved for use in autologous bone marrow transplants, but little is known of the incidence of reactions in patients transfused with these cryopreserved marrows. Reactions in patients transfused during a 4-year period with 134 autologous marrows cryopreserved in dimethyl sulfoxide (DMSO) were compared with those in patients transfused with marrow that had been collected from HLA-compatible donors and that had not been cryopreserved. Patients transfused with cryopreserved marrow had significantly more nausea (44.8 vs. 14.1%; p less than 0.0005), vomiting (23.9 vs. 8.5%; p less than 0.01), chills (31.3 vs. 1.4%; p less than 0.0005), and fever (17.9 vs. 0%; p less than 0.005) than patients transfused with fresh allogeneic marrow. The incidence of emesis correlated with the dose of DMSO received, but that of nausea did not. All cryopreserved marrows were cultured for bacteria at the time of transfusion and 17 (12.7%) were found to be positive. Only 1 of the 17 patients transfused with culture-positive marrow developed sepsis during the transplant course with the same organism that was present in the transfused marrow. Although the reactions in donors transfused with cryopreserved marrow were readily treated, this study suggests that the incidence of some reactions might be decreased by reducing the dose of DMSO transfused. Bacterial contamination of transfused marrow was a worrisome complication, and efforts should be made to improve marrow collection and processing techniques to minimize that risk. 相似文献
883.
Low incidence of HTLV infections in random blood donors with indeterminate western blot patterns 总被引:6,自引:0,他引:6
S Kwok ; JJ Lipka ; N McKinney ; DE Kellogg ; B Poiesz ; SK Foung ; JJ Sninsky 《Transfusion》1990,30(6):491-494
Peripheral blood mononuclear cells (PBMCs) were recovered from platelet units of 61 blood donors who were HTLV-I positive and 3 blood donors who were HTLV-I negative on enzyme-linked immunosorbent assay (ELISA). Western blot analyses were performed on the sera and DNA was prepared from the PBMCs and analyzed by the polymerase chain reaction (PCR). Of the 61 repeatably reactive samples, 2 were positive, 26 were negative, and 33 were interpreted as indeterminate on Western blot. HTLV-II sequences were detected by PCR in one of the Western blot-positive samples, as well as in one Western blot-indeterminate sample that showed reactivity to p24 only. HTLV-I sequences were detected in the second Western blot-positive sample. HTLV sequences were not detected in the remaining samples, which suggested that the majority of individuals with indeterminate results on Western blots that used one set of commercially available reagents are not infected with HTLV. It is demonstrated in this study that PCR can be used not only to resolve the infection status of individuals with indeterminate Western blots but also to distinguish between HTLV-I and HTLV-II. 相似文献
884.
JM O'Donoghue MCh FRCSI SK Al-Ghazal MSurg JJ McCann BSc FRCSI 《International journal of clinical practice》1996,50(2):108-110
SUMMARY Alkali burns to the extremities are unusual, but they are also a cause of significant morbidity, often because of their late presentation. Their management centres around water lavage, burn debridement and split-skin grafting; there is controversy over the timing of surgery. Three unusual cases of caustic soda burn in adults, and the difficulties encountered in their management, are described, and the literature is reviewed. 相似文献
885.
Background
In patients with Polycystic Ovarian Syndrome (PCOS), resolution of infertility is an important goal of treatment. Wedge resection of the ovaries described as a means to achieve this was practiced in the middle of twentieth century. With the advent of endoscopic surgery, surgical approach for the same condition has been modified. Multi point biopsy, multiple needle puncture, electofulguration and laser fulguration are being tried in the context of PCOS. This project was taken up to evaluate the scope of electo fulguration in clomiphene resistant PCOS.Methods
Forty patients who did not show sonographic evidence of ovulation with clomiphene citrate (CC) 100mg OD for 05 days in two cycles were subjected to laparoscopy. The patients who did not show any pelvic factor for infertility were alternately assigned to electro - fulguration treatment of ovaries or no fulguration during laparoscopy. These were designated as ‘Lap EC’ & ‘Only CC’ group respectively. For ‘Only CC’ group’ stimulation with CC was continued for four cycles with a higher dose 150 mg OD for 05 days. Lap EC group were subjected to CC 100mg OD for 5 days for two cycles in case of non achievement of ovulation in the first two drug free cycles following EC. Folliculometry, HCG administration and Intra Uterine Insemination (IUI) was performed for both groups.Results
Total percentage of ovulatory cycles were 51.8% in EC group compared to 5.26% in the CC group. Overall pregnancy rate of 30% was achieved in the Lap EC group as compared to only 10% in the CC group (p<0.05).Conclusion
Laparoscopic electrofulguration of ovaries increases the chances of ovulation and conception. This being a cheaper one time procedure as compared to other expensive ovulation inducing agents, should be the preferred mode and the primary procedure wherever polycystic ovaries are encountered while evaluating a case of infertility by laparoscopy.Key Words: Infertility, PCOS, Electrofulguration 相似文献886.
S Tak G Ahluwalia SK Sharma S Mukhopadhya R Guleria JN Pande 《Journal of Medical Imaging and Radiation Oncology》1999,43(4):451-455
The exact role of fibre-optic bronchoscopy (FOB) and CT of the chest in the diagnosis of patients presenting with haemoptysis and a normal or non-localizing chest radiograph has not been clearly defined. A study was designed to evaluate 50 patients presenting with haemoptysis and a normal or non-localizing chest radiograph using FOB and high-resolution computed tomography (HRCT). A definitive diagnosis was established in 17 (34%) patients. The aetiologies included bronchiectasis (24%), bronchial adenoma (6%), tuberculosis (2%) and bronchitis (2%). The diagnosis was made by HRCT in 15 (30%) patients, while FOB was diagnostic in five (10%) patients. The diagnosis was made by HRCT and FOB in all patients with focal airway abnormalities. Therefore, HRCT effectively delineated abnormalities of both the central and peripheral airways. It is concluded that CT should be obtained prior to FOB in all patients presenting with haemoptysis and a normal or non-localizing chest radiograph. 相似文献
887.
888.
Iman Hazra Omar Faruk SK Md Ankur Datta Somnath Mondal Saibal Moitra Manoj Kumar Singh Suhnrita Chaudhuri Prasanta Kumar Das Anjan Kumar Basu Indranil Dhar Nandita Basu Swapna Chaudhuri 《Scandinavian journal of immunology》2019,89(2)
Cryptococcus neoformans, the encapsulated yeast acquired through inhalation, remains localized in lungs, but harbours the CNS in immunocompromised individuals. Several treatment regimes have failed combating this disease totally, but long‐term usage of drugs leads to organ damage. As T11‐target structure (T11TS) has documented profound immune potentiation, we aimed to investigate the role of microglia, pivotal immune cells of brain in ameliorating cryptococcosis, with T11TS immunotherapy. Murine model with C neoformans infection was prepared by intraperitoneal injection and the brains of rats examined 7 days post‐infections for histopathology by PAS and Alcian blue staining corroborated with organ fungal burden evidencing restorative T11TS action on Cryptococcal meningitis. Immunotherapy with three doses of T11TS, a CD2 ligand, in C neoformans infected rats, upregulates toll‐like receptors 2, ?4 and ?9 of microglia, indicating increased phagocytosis of the fungus. Flowcytometric analysis revealed increased numbers of T11TS treated brain infiltrating CD4+ and CD8+ T‐lymphocytes along with increased MHC I and MHC II on microglia, activating the infiltrating lymphocytes aiding the killing mechanism. Present study also indicated that T11TS increased production of Th1 inflammatory cytokines conducive to fungal elimination while the inhibitory Th2 cytokines were dampened. This preclinical study is first of its kind to show that T11TS effected profound immune stimulation of microglial activity of C neoformans infected rats eradicating residual fungal burden from the brain and can be a useful therapeutic strategy in fighting against this deadly disease. 相似文献
889.
McLaren J; Dealtry G; Prentice A; Charnock-Jones DS; Smith SK 《Human reproduction (Oxford, England)》1997,12(6):1307-1310
Endometriosis is characterized by an increase in the number, activation and
secretory activity of peritoneal fluid macrophages. Factors regulating the
activation of these cells may be important in the pathophysiology of this
disease. In this study we measured by enzyme- linked immunosorbent assay
the concentrations of the macrophage inhibitory factor interleukin (IL)-13
in the peritoneal fluid of women with and without endometriosis. It was
found that women with endometriosis had significantly lower amounts of
IL-13 (95 +/- 9.8 pg/ml) in peritoneal fluid, compared with women without
endometriosis (115 +/- 30 pg/ml) (P < 0.01). No cycle-specific variation
was evident for either group. Another macrophage inhibitory interleukin
(IL-10) was also measured, but no differences between women with (16.1 +/-
13.2 pg/ml) or without (10.3 +/- 5.6 pg/ml) endometriosis were seen. The
immunolocalization of IL-13 was assessed in eutopic and ectopic endometrium
and in isolated peritoneal fluid cells. Glandular epithelial cells and
stromal cells in both eutopic and ectopic endometrium were immunopositive
for IL-13. No cycle-specific differences in the immunolocalization of IL-13
were seen. In conclusion, the reduced amounts of IL-13 in the peritoneal
fluid of women with endometriosis may lead to a lack of suppression of
macrophage activation, thereby contributing to the overall pathogenesis of
this disease.
相似文献
890.
Avalos BR; Hunter MG; Parker JM; Ceselski SK; Druker BJ; Corey SJ; Mehta VB 《Blood》1995,85(11):3117-3126
The human granulocyte colony-stimulating factor receptor (hG-CSFR) belongs to the cytokine receptor superfamily. As with other members of this family, the cytoplasmic domain of hG-CSFR lacks intrinsic tyrosine kinase activity. To identify critical regions mediating growth signal transduction by hG-CSFR, deletions or site-directed amino acid substitutions were introduced into the cytoplasmic domain of hG-CSFR, and the mutant cDNAs were transfected into the murine interleukin-3 (IL- 3)-dependent Ba/F3 and FDCP cell lines. Truncation of the carboxy- terminal end of the receptor to the membrane-proximal 53 amino acids of the cytoplasmic domain, which retained the conserved Box 1 and Box 2 sequence motifs, decreased the ability of hG-CSFR to transduce G-CSF- mediated growth signals without an associated loss in receptor binding affinity. Substitution of proline by alanine at amino acid positions 639 and 641 within Box 1 completely abolished the G-CSF-mediated growth signal. Rapid induction of tyrosine phosphorylation of several cellular proteins, including a 75-kD protein (p75) identified as c-rel, was an early event associated with transduction of proliferative signals by hG- CSFR in Ba/F3 transfectants. Mutant receptors containing Pro-to-Ala substitutions that inactivated the receptor for mitogenic activity also inactivated the receptor for tyrosine-specific phosphorylation of p75. These results show that the conserved Box 1 sequence motif (amino acids 634 to 641) is critical for mitogenesis and activation of cellular tyrosine kinases by hG-CSFR. 相似文献