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11.
12.
P M Doraiswamy K R Krishnan O B Boyko M M Husain G S Figiel V J Palese P R Escalona S A Shah W M McDonald W J Rockwell 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(3):351-356
1. The frequent occurrence of hypothalamo-pituitary dysfunction in patients with eating disorders as well as prior reports that nutritional and endocrine status influence pituitary morphology, led us to hypothesize that pituitary size and shape may be altered in patients with eating disorders. 2. Magnetic resonance imaging (MRI) does not use ionizing radiation and is currently one of the most feasible modalities available to study the pituitary gland in vivo. Using MRI, we have previously reported in a preliminary study that female patients with eating disorders had significantly smaller pituitary glands than controls. In addition MRI excluded any pituitary mass lesions. 3. In this report, we confirm our previous MRI findings and provide further evidence of pituitary abnormalities in an expanded sample of eating disorder patients. Preliminary data on pituitary volume estimates from MRI scans are provided for a subset of patients and controls. 相似文献
13.
We studied the relationship between arterial carbon dioxide tension (PaCO2) and fresh gas flow (FGF) during use of the Bain breathing circuit for Caesarean section anaesthesia. Thirty-one patients undergoing Caesarean section were anaesthetised using the Bain circuit with intermittent positive pressure ventilation. The PaCO2 were measured at FGF of 70 ml X kg-1 X min-1, 80 ml X kg-1 X min-1, and 100 ml X kg-1 X min-1. The FGF requirement to maintain a given PaCO2 during Caesarean section anaesthesia is the same as the requirements for nonpregnant subjects, despite the increase in carbon dioxide production associated with pregnancy. This is probably because the total FGF determined by body weight and given during Caesarean section anaesthesia is 15-20 per cent higher than nonpregnant levels, due to the weight gain associated with pregnancy. A FGF of 100 ml X kg-1 of pregnant weight/min maintains PaCO2 of 4.44 kPa predelivery, which is in the desirable range of PaCO2 during Caesarean section. 相似文献
14.
T. Pinzer M. Reiß H. Bourquain K. G. Krishnan G. Schackert 《Acta neurochirurgica》2006,148(10):1085-1090
Summary Aspergillosis belongs to the group of mycotic diseases of paranasal sinuses. The invasive forms, and particularly the fulminant
forms, are potentially fatal. Isolated aspergillosis of the sphenoid sinus or the clivus is a difficult diagnosis, since the
often misleading clinical manifestations of this rare disease develop late. These patients become apparent by neurological
signs such as cavernous sinus syndrome, pseudotumor of the pituitary or the orbit. Diagnosis is often made intra-operatively
or on histological examination.
We report a case of invasive aspergillosis uniquely involving the sellar area revealed by clinical features suggesting a pseudotumor
of the pituitary. Although such lesions are almost always seen in immune suppressed subjects, in our case, the patient was
immune competent and had no past history of sinusitis.
The question of whether, and when to perform limited or extensive surgery remains an issue for discussion, owing to the rarity
of this disease honed by lack of experience. It depends on several factors: the kind of disease, the immunity, the subtype
of invasive fungal sinusitis and the degree of tissue invasion. 相似文献
15.
Duct-associated lymphoid tissue (DALT) of minor salivary glands and mucosal immunity. 总被引:3,自引:0,他引:3
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Minor salivary glands (MSG) play a substantial role in the secretory immunoglobulin A (sIgA)-mediated immunity of the oral cavity. There are two possibilities for the induction of this immunity: (i) an explicitly local antigenic stimulus, or (ii) a remote stimulus as part of the so-called 'common mucosal immune system'. This communication is an attempt to consolidate available evidence in support of both possibilities and to address the former in detail. Although there is strong circumstantial evidence supporting the feasibility of MSG functioning as a part of the common mucosal immune system, direct experimental evidence is yet to emerge. On the other hand, there is increasing structural and physiological evidence in support of MSG serving as a local immunological organ. The purely local response is attributed to the presence of MSG duct-associated lymphoid tissue (DALT), which is comparable to gut- or bronchial-associated lymphoid tissue (GALT or BALT) in origin, tissue organization and function. DALT is accessible to oral antigens by retrograde passage through MSG ducts. Repeated topical antigenic challenging via the oral mucosa may result in the appearance of interacinar plasma cells carrying specific homologous antibodies in MSG. Gut or enteric priming of the same antigen, by passing the oral mucosa by gastric intubation, need not evoke a remote immune response in MSG. Since DALT is more likely to occur in healthy, young growing individuals, who are less likely to undergo bioptic examination of MSG, it has not yet been documented in humans. The physiologically induced DALT is apt to be confused with focal accumulations of lymphoid tissue in pathologically altered MSG, as a consequence of local and some systemic autoimmune diseases. An attempt is made to demarcaate healthy and pathological MSG on the basis of currently available clinical, serological, immunological and genetic evidence. 相似文献
16.
17.
R Nair K Prabhash M Sengar A Bakshi S Gujral S Gupta P Parikh 《Annals of oncology》2007,18(7):1243-1245
BACKGROUND: Various malignancies and cytotoxic chemotherapy have been proposed to increase the risk of reactivation of tuberculosis. Available literature to support this observation is still conflicting. There is scarcity of data from countries with rampant tubercular infection, such as India, in this regard. DESIGN AND METHODS: In the present retrospective analysis, patients with high-grade non-Hodgkin's lymphoma with past history of tuberculosis and have had adequate antitubercular therapy were identified from a Lymphoma Group study. These patients were followed up during cytotoxic chemotherapy and later to assess the risk of reactivation. RESULTS: A cohort of eight patients with past history of tuberculosis was selected from 141 patients of high-grade non-Hodgkin's lymphoma. The median age was 33.5 years (range, 24-53 years). Median duration between completion of antitubercular treatment and diagnosis of lymphoma was 5 years (range, 1.5-10 years). All patients received cyclical cytotoxic chemotherapy. The median duration of follow up after completion of chemotherapy was 5 years (range, 10 months to 5 years). None of these patients developed reactivation of tuberculosis. CONCLUSION: Cyclical chemotherapy for non-Hodgkin's lymphoma does not lead to reactivation of tuberculosis. 相似文献
18.
19.
Advancement Flaps: A Basic Theme with Many Variations 总被引:1,自引:0,他引:1
Krishnan Ravi MD Garman Mary MD Nunez-Gussman Janna MD Orengo Ida MD 《Dermatologic surgery》2005,31(S2):986-994
Background. The advancement flap involves the linear advancement of tissue in one direction. Despite its straightforwardness and simple concept, it can be used to close a variety of defects, ranging from small defects on the scalp or extremities to large, complicated defects involving cosmetic units on the face.
Objectives. To provide a basic and useful review for the indications, advantages, disadvantages, and techniques for the use of advancement flaps in the reconstruction of defects in dermatologic surgery.
Materials and Methods. We performed a literature search for articles discussing advancement flaps and compiled a brief review of our findings.
Results. The movement of the advancement flap must be balanced by the blood supply of the flap. The excision of Burow's triangles along various aspects of the advancement flap can increase movement and improve cosmesis of the flap. The types of advancement flaps discussed include the single advancement flap, double advancement flap, A-T flap (O-T flap), Burow's triangle flap (Burow's wedge flap), crescenteric advancement flap, island pedicle flap (V-Y flap), helical rim advancement flap, and facelift flap.
Conclusion. Advancement flaps are versatile and useful basic flaps for repairing defects. 相似文献
Objectives. To provide a basic and useful review for the indications, advantages, disadvantages, and techniques for the use of advancement flaps in the reconstruction of defects in dermatologic surgery.
Materials and Methods. We performed a literature search for articles discussing advancement flaps and compiled a brief review of our findings.
Results. The movement of the advancement flap must be balanced by the blood supply of the flap. The excision of Burow's triangles along various aspects of the advancement flap can increase movement and improve cosmesis of the flap. The types of advancement flaps discussed include the single advancement flap, double advancement flap, A-T flap (O-T flap), Burow's triangle flap (Burow's wedge flap), crescenteric advancement flap, island pedicle flap (V-Y flap), helical rim advancement flap, and facelift flap.
Conclusion. Advancement flaps are versatile and useful basic flaps for repairing defects. 相似文献
20.
A Abraham M G Nair R L Kisliuk Y Gaumont J Galivan 《Journal of medicinal chemistry》1990,33(2):711-717
Representative examples of folate and antifolate poly-gamma-glutamyl metabolites were synthesized via the [(9-fluorenylmethoxy)oxy]carbonyl (Fmoc) chemistry using the KH polyamide resin. Polyglutamate yields were consistently better in all cases compared to the previous Merrifield method, and the crude products were obtained in greater than 85% purity. The symmetrical anhydride (7) derived from alpha-tert-butyl N-Fmoc-L-glutamate (6) was used for the initial coupling of the first glutamate residue to the KH resin and also for subsequent chain elongation. The alpha-tert-butyl protective groups were not labile under the conditions used for the cleavage of the finished peptide from the resin. A series of poly-gamma-glutamyl metabolites of methotrexate (MTX) with a chain length ranging from two to five glutamyl residues were synthesized and coupled with poly(L-lysine) having an average molecular weight of 27,000 and 52,000. Each conjugate was tested for its ability to inhibit the growth of wild type (H35) and MTX transport resistant (H35R) strains of hepatoma cells in culture, the latter having a 100-fold reduced sensitivity to MTX. 4-Amino-4-deoxy-N10-methylpteroylglutamyl-gamma-glutamylpoly (L-lysine) conjugate [MTX(G2)-poly-L-Lys-52000] and MTX(G4)-poly-L-Lys-52000 were among the most active (I50 = 8.0 and 10 nM against H35 cells) MTX-polylysines synthesized to date, and they were somewhat more inhibitory to the transport resistant cells. MTX(G5)-poly-L-Lys-52000 was approximately 1000 times more effective than MTX(G5)-poly-D-Lys-52000 in inhibiting the growth of H35R hepatoma cells in culture, indicating that internal cleavage of the gamma-glutamate chain of the conjugate with subsequent release of MTX or shorter chain polyglutamates of MTX is unlikely to be an important determinant of MTX-polyglutamate polylysine cytotoxicity. The results indicate that MTX-polyglutamate poly(L-lysine) conjugates are taken up by the cells independently of MTX and probably via endocytosis. 相似文献