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631.
A criticism of the use of an endoprosthesis for relief of biliary obstruction has been the difficulty of removing or exchanging the endoprosthesis if it becomes obstructed. We present a simple method of removal that has been successful in four of five patients who presented with an obstructed endoprosthesis 3-7 months after placement. 相似文献
632.
Rifampicin-associated acute renal failure: pathophysiologic, immunologic, and clinical features 总被引:1,自引:0,他引:1
AS De Vriese DL Robbrecht RC Vanholder DP Vogelaers NH Lameire 《American journal of kidney diseases》1998,31(1):108-115
A 71-year-old woman was treated for a relapsing pulmonary tuberculosis with reinstitution of rifampicin after a medication-free interval of 2 years. After ingestion of the second dose, she developed severe hemolytic anemia and acute renal failure (ARF) necessitating dialysis. We demonstrated the presence in the patient's serum of rifampicin-dependent immunoglobulin G (IgG) and IgM antibodies, which caused red blood cell lysis through interaction with the I antigen on the erythrocyte surface. A review of the literature yielded 48 cases of rifampicin-associated renal failure. A subgroup of 37 patients could be distinguished, which, analogous to our case, suddenly developed ARF and frequently also developed hemolytic anemia and/or thrombocytopenia during intermittent or interrupted treatment. Regarding the pathogenesis of the ARF, renal biopsy consistently revealed tubular lesions. Although intravascular hemolysis with hemoglobinuria may play a role, it is not uniformly present. Our demonstration of an antibody with anti-I specificity provides a possible explanation. The I antigen is also expressed on tubular epithelium and may, therefore, be the target structure through which rifampicin-antibody complexes lead to tubular cell destruction. The other cases of rifampicin-associated ARF were unrelated to this subgroup: two cases of rapidly progressive glomerulonephritis, five cases of acute interstitial nephritis, and four cases of light chain proteinuria were recorded. 相似文献
633.
634.
Background
Detection of cytologic atypia in nipple aspirate fluid (NAF) has been shown to be a predictor of risk for development of breast carcinoma. Manual collection of NAF for cytologic evaluation varies widely in terms of efficacy, ease of use, and patient acceptance. We investigated a new automated device for the non-invasive collection of NAF in the office setting. 相似文献635.
Background
Recruitment in the Army is subject to medical fitness as per laid down standards. A study of the frequency of referral and rejection gives us an understanding as to where to lay stress in the Ear Nose Throat Examination during recruitment medical. Method: A three year analysis of candidates reporting for review of ENT disabilities was carried out from January 1999 to December 2001.Results
Of the 1156 candidates, 888(76.8%) were found to be fit. The commonest cause for rejection was Wax in ears in 496 cases (43%). 428(86.3%) were found to be fit on review. Chronic suppurative otitis media (21.9%) and tympanosclerosis (21.3%) were the other causes for rejection.Conclusion
The desirable situation is wherein the evaluation by the specialist is in minimal variation with that of the initial recruitment medical examination. Awareness to have ears cleaned for wax before appearing for the examination, provision of better examination ambiance and equipment and a short training capsule will be beneficial to reduce the number of review cases to referral hospitals.Key Words: Hearing assessment, recruitment, tympanic membrane 相似文献636.
Diadenosine 5',5'-p1,p4-tetraphosphate deficiency in blood platelets of the Chediak-Higashi syndrome
Diadenosine tetraphosphate (AP4A) is an unusual nucleotide found in a variety of cells, including platelets. It has been suggested that platelet AP4A is stored in the dense granules and is metabolically inactive. We have studied the AP4A content of blood platelets in two patients and three cattle with Chediak-Higashi syndrome (CHS), a hereditary platelet defect with dense granule deficiency. Acid-soluble extractions of whole blood and platelets were neutralized. The adenosine triphosphate (ATP) level was measured by luminescence technique. To measure the AP4A content, the neutralized extract was treated with phosphomonoesterase for removal of ATP. The AP4A content was then measured by coupling the phosphodiesterase and luciferase reaction. The AP4A content was 0.43 nmol/mg protein for normal human platelets and 0.004 nmol/mg protein for CHS platelets. The ATP/AP4A ratio was 67 for normal and 3,023 for CHS platelets. The whole blood AP4A was reduced by 89% in CHS patients who had only a slight decrease in ATP level (26% reduction). Similarly, bovine platelets with CHS showed a marked decrease of AP4A content and a moderate reduction of the ATP level. The platelet ATP/AP4A ratio was 351 and 3,133 for normal and CHS cattle, respectively. Results demonstrate a marked reduction of AP4A in CHS platelets and suggest that AP4A may be a useful marker for the measurement of dense granule content in platelets. 相似文献
637.
ROSA M. MARTÍ M.D. TERESA ESTRACH M.D. JUAN C. REVERTER M.D. ELÍAS CAMPO M.D. ROSA BRUGUÉS M.D. MIGUEL BRUGUERA M.D. JOSÉ M. MASCARÓ M.D. 《International journal of dermatology》1996,35(6):450-454
Background. The wide use of staging procedures, looking for visceral involvement in patients with cutaneous T-cell lymphoma (CTCL), is controversial, especially in the early stages. In this study, we analyzed the results of bone marrow biopsy and laparoscopy with liver biopsy in a series of 43 patients with CTCL. Methods. Clinicopathologic stages were established by a modification of the TNM system proposed in 1979. Results of staging procedures were correlated with blood cell counts and laboratory tests. The usefulness of the staging procedures was analyzed particularly in patients without clinical or biologic evidence of extracutaneous disease. Results. The patient's median age was 66 years; 35 patients were men and eight women. The clinicopathologic stages were as follows: T1: 3 cases; T2: 15; T3: 14; T4: 11; NO: 15; N1: 28; MO: 38; Ml: 5; BO: 37; and B1: 6 cases. Internal lymph node disease, diagnosed by lymphangiography and/or abdominal scanning, was demonstrated in 37% of patients. Bone marrow infiltration was seen in 12% of patients and was the only form of visceral involvement. All liver biopsies were negative. Serum lactate dehydrogenase (LDH) levels were raised in patients with lymph node disease; it was the only laboratory test that correlated with extracutaneous involvement. Staging procedures changed three of the nine patients with a clinical T1-T2N0M0B0 stage (33%) to a more advanced stage. The abdominal lymph node evaluation allowed a reclassification from NO to N1 in two of nine cases (22%); one of the remaining cases was reclassified from MO to M1 on the basis of bone marrow biopsy results. Conclusions. Our results indicate that bone marrow biopsy is a useful investigational procedure for determining extracutaneous disease in CTCL. Peritoneoscopy with liver biopsy rarely is informative; however, as our study does not include a very large number of patients, these preliminary conclusions must be confirmed in the future by including more cases. 相似文献
638.
Sundberg K; Johansson AS; Stenberg G; Widersten M; Seidel A; Mannervik B; Jernstrom B 《Carcinogenesis》1998,19(3):433-436
Previous studies have identified allelic variants of the human glutathione
transferase (GST) Pi gene and showed that the two different encoded
proteins with isoleucine (GSTP1-1/I-105) or valine (GSTP1-1/V- 105) at
position 105, respectively, differ significantly in their catalytic
activities with model substrates. Moreover, recent epidemiological studies
have demonstrated that individuals differing in the expression of these
allelic variants also differ in susceptibility to tumour formation in
certain organs, including such in which polycyclic aromatic hydrocarbons
(PAH) may be etiological factors. In the present study the catalytic
efficiencies (kcat/Km) of these GSTP1-1 variants were determined with a
number of stereoisomeric bay-region diol epoxides, known as the ultimate
mutagenic and carcinogenic metabolites of PAH, including those from
chrysene, benzo[a]pyrene and dibenz[a,h]anthracene. In addition, GSTP1-1
mutants in which amino residue 105 is alanine (GSTP1-1/A-105) or tryptophan
(GSTP1-1/W-105) have been constructed and characterized. GSTP1-1/V-105 was
found to be more active than GSTP1-1/I-105 in conjugation reactions with
the bulky diol epoxides of PAH, being up to 3-fold as active towards the
anti- and syn-diol epoxide enantiomers with R-absolute configuration at the
benzylic oxiranyl carbon. Comparing the four enzyme variants, GSTP1-1/A-
105 generally demonstrated the highest kcat/Km value and GSTP1-1/W-105 the
lowest with the anti-diol epoxides. A close correlation was observed
between the volume occupied by the amino acid residue at position 105 and
the value of kcat/Km. With the syn-diol epoxides, such a correlation was
observed with alanine, valine and isoleucine, whereas tryptophan was
associated with increased kcat/Km values. The mutational replacement of
isoleucine with alanine or tryptophan at position 105 did not alter the
enantio selectivity of the GSTP1-1 variants compared with the naturally
occurring allelic variants GSTP1-1/I-105 and GSTP1- 1/V-105. Since the
amino acid at position 105 forms part of the substrate binding site
(H-site) the effect of increasing bulkiness is expected to cause restricted
access of the diol epoxide and proper alignment of the two reactants for
efficient glutathionylation. In conclusion, the present study indicates
that individuals who are homozygous for the allele GSTP1* B (coding for
GSTP1-1/V-105) display a higher susceptibility to malignancy because of
other factors than a decreased catalytic efficiency of GSTP1-1/V-105 in the
detoxication of carcinogenic diol epoxides of benzo[a]pyrene or
structurally related PAH.
相似文献
639.
640.