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1.
Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome. 相似文献
2.
Sherry X Yang Richard M Simon Antoinette R Tan Diana Nguyen Sandra M Swain 《Clinical cancer research》2005,11(17):6226-6232
PURPOSE: To delineate gene expression patterns and profile changes in metastatic tumor biopsies at baseline and 1 month after treatment with the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor erlotinib in patients with metastatic breast cancer. EXPERIMENTAL DESIGN: Patients were treated with 150 mg of oral erlotinib daily. Gene expression profiles were measured with Affymetrix U133A GeneChip and immunohistochemistry was used to validate microarray findings. RESULTS: Estrogen receptor (ER) status by immunohistochemistry is nearly coincided with the two major expression clusters determined by expression of genes using unsupervised hierarchical clustering analysis. One of 10 patients had an EGFR-positive tumor detected by both microarray and immunohistochemistry. In this tumor, tissue inhibitor of metalloproteinases-3 and collagen type 1 alpha 2, which are the EGF-down-regulated growth repressors, were significantly increased by erlotinib. Gene changes in EGFR-negative tumors are those of G-protein-linked and cell surface receptor-linked signaling. Gene ontology comparison analysis pretreatment and posttreatment in EGFR-negative tumors revealed biological process categories that have more genes differentially expressed than expected by chance. Among 495 gene ontology categories, the significant differed gene ontology groups include G-protein-coupled receptor protein signaling (34 genes, P = 0.002) and cell surface receptor-linked signal transduction (74 genes, P = 0.007). CONCLUSIONS: ER status reflects the major difference in gene expression pattern in metastatic breast cancer. Erlotinib had effects on genes of EGFR signaling pathway in the EGFR-positive tumor and on gene ontology biological process categories or genes that have function in signal transduction in EGFR-negative tumors. 相似文献
3.
4.
Bill J Gurley Ashley Swain Gary W Barone D Keith Williams Philip Breen C Ryan Yates Leslie B Stuart Martha A Hubbard Yudong Tong Sreekhar Cheboyina 《Drug metabolism and disposition》2007,35(2):240-245
Phytochemical-mediated modulation of P-glycoprotein (P-gp) and other drug transporters may give rise to many herb-drug interactions. Serial plasma concentration-time profiles of the P-gp substrate, digoxin, were used to determine whether supplementation with goldenseal or kava kava modified P-gp activity in vivo. Twenty healthy volunteers were randomly assigned to receive a standardized goldenseal (3210 mg daily) or kava kava (1227 mg daily) supplement for 14 days, followed by a 30-day washout period. Subjects were also randomized to receive rifampin (600 mg daily, 7 days) and clarithromycin (1000 mg daily, 7 days) as positive controls for P-gp induction and inhibition, respectively. Digoxin (Lanoxin, 0.5 mg) was administered p.o. before and at the end of each supplementation and control period. Serial digoxin plasma concentrations were obtained over 24 h and analyzed by chemiluminescent immunoassay. Comparisons of area under the curve (AUC)((0-3)), AUC((0-24)), C(max,) CL/F, and elimination half-life were used to assess the effects of goldenseal, kava kava, rifampin, and clarithromycin on digoxin pharmacokinetics. Rifampin produced significant reductions (p < 0.01) in AUC((0-3)), AUC((0-24)), CL/F, t(1/2), and C(max), whereas clarithromycin increased these parameters significantly (p < 0.01). With the exception of goldenseal's effect on C(max) (14% increase), no statistically significant effects on digoxin pharmacokinetics were observed following supplementation with either goldenseal or kava kava. When compared with rifampin and clarithromycin, supplementation with these specific formulations of goldenseal or kava kava did not appear to affect digoxin pharmacokinetics, suggesting that these supplements are not potent modulators of P-gp in vivo. 相似文献
5.
A preliminary report of the short-term effect of carbonated beverage consumption on calcium metabolism in normal women 总被引:2,自引:0,他引:2
S Smith J Swain E M Brown G Wyshak T Albright V A Ravnikar I Schiff 《Archives of internal medicine》1989,149(11):2517-2519
A variety of nutritional factors influence the bioavailability of calcium and increase a woman's risk of osteoporosis. Eight healthy women completed an 8-week metabolic study designed to investigate the effect of nonalcoholic carbonated beverage consumption on calcium metabolism. Compared with women receiving a control diet, women consuming a diet high in nonalcoholic carbonated beverages demonstrated similar mean serum levels of calcium, ionized calcium, phosphorus, alkaline phosphatase, parathyroid hormone, 1,25-dihydroxyvitamin D3, and osteocalcin. Twenty-four-hour urine volume, creatinine clearance, calcium-creatinine ratio, and phosphorus-creatinine ratio were similar during consumption of the diet high in nonalcoholic carbonated beverages and the control diet. Twenty-four-hour cyclic adenosine monophosphate-creatinine ratio was significantly lower in women consuming the diet high in nonalcoholic carbonated beverage compared with women receiving the control diet (342 +/- 27.4 nmol/mmol vs 409 +/- 22.1 nmol/mmol). Consumption of a diet high in nonalcoholic carbonated beverages on a short-term basis does not appear to affect adversely the serum or urinary markers of calcium metabolism. 相似文献
6.
RA O. Hempel 《Notfall & Rettungsmedizin》2007,10(5):367-371
Legal uncertainties for emergency vehicle drivers can be avoided when fundamental rules are established. In particular, differentiation of special rights and rights of way is essential. Inherent in both is the urgency necessary to save human lives. The right of way signaled by flashing blue lights and siren does not however justify traffic violations but signifies rather a request to other traffic participants. In contrast, special rights require no announcement and constitute a justifiable reason for traffic violations. Even so they do not allow that other traffic participants be endangered or harmed. Adherence to these basic principles can prevent legal misinterpretations as well as rigid adoption of inflexible standards of behavior. 相似文献
7.
RA Mag. Dr. C. Gepart 《Notfall & Rettungsmedizin》2007,10(4):289-292
Austria’s new Living Wills Act (Patientenverfügungsgesetz, or PatVG) that came into effect on 1st of June 2006, is the first law in Austria to regulate the controversial issue of living wills. The PatVG provides for a right to refuse future medical treatment by making an advance directive in the form of a living will that is either binding or “to be taken into consideration”. However, the establishment of a binding living will is governed by strict criteria as regards form and content, and both a medical doctor and a legal expert must be involved. Compliance with a living will is not allowed where there is a legal obligation to give medical treatment. There is also a legal obligation to give medical treatment in emergency situations where the time involved in looking for a living will could seriously endanger the health or the life of a patient. 相似文献
8.
Phospho-akt expression is associated with a favorable outcome in non-small cell lung cancer. 总被引:3,自引:0,他引:3
Amit Shah William A Swain Donna Richardson John Edwards Duncan J Stewart Catherine M Richardson Daniel E B Swinson Dipika Patel J Louise Jones Kenneth J O'Byrne 《Clinical cancer research》2005,11(8):2930-2936
Akt, a Serine/Threonine protein kinase, mediates growth factor-associated cell survival. Constitutive activation of Akt (phosphorylated Akt, P-Akt) has been observed in several human cancers, including lung cancer and may be associated with poor prognosis and chemotherapy and radiotherapy resistance. The clinical relevance of P-Akt in non-small cell lung cancer (NSCLC) is not well described. In the present study, we examined 82 surgically resected snap-frozen and paraffin-embedded stage I to IIIA NSCLC samples for P-Akt and Akt by Western blotting and for P-Akt by immunohistochemistry. P-Akt protein levels above the median, measured using reproducible semiquantitative band densitometry, correlated with a favorable outcome (P = 0.007). Multivariate analysis identified P-Akt as a significant independent favorable prognostic factor (P = 0.004). Although associated with a favorable prognosis, high P-Akt levels correlated with high tumor grade (P = 0.02). Adenocarcinomas were associated with low P-Akt levels (P = 0.039). Akt was not associated with either outcome or clinicopathologic variables.Cytoplasmic (CP-Akt) and nuclear (NP-Akt) P-Akt tumor cell staining was detected in 96% and 42% of cases, respectively. Both CP-Akt and NP-Akt correlated with well-differentiated tumors (P = 0.008 and 0.017, respectively). NP-Akt also correlated with nodal metastases (P = 0.022) and squamous histology (P = 0.037).These results suggest P-Akt expression is a favorable prognostic factor in NSCLC. Immunolocalization of P-Akt, however, may be relevant as NP-Akt was associated with nodal metastases, a known poor prognostic feature in this disease. P-Akt may be a potential novel therapeutic target for the management of NSCLC. 相似文献
9.
Ohne Zusammenfassung 相似文献
10.
Both cyproterone acetate (CPA) and the gonadotrophin-releasing hormone
agonist (GnRHa) have been shown to be effective for the treatment of
hirsutism. We wished to compare the effectiveness of CPA in two standard
doses with GnRHa and add-back therapy and to compare the length of
remission after these treatments. A total of 60 hirsute hyperandrogenic
women was assigned to the following treatment groups: CPA 2 mg with 35
microg of ethinylestradiol for 21 days each month (Diane group), CPA 50 mg,
days 5-15, and ethinylestradiol 50 microg, days 5-25, each month (CPA
group) or Decapeptyl 3.75 mg i.m. every 28 days with the addition of
conjugated oestrogen 0.625 mg, days 1-21, and medroxyprogesterone acetate
10 mg, days 12-21 (GnRHa group). Hirsutism was graded by the
Ferriman-Gallwey-Lorenzo (FGL) index and anagen hair shaft diameters and
serum luteinizing hormone (LH) and testosterone were assessed before and
every 3 months during and after treatment. All women were treated for 1
year with 1 year follow-up. At baseline hirsutism and endocrine patterns
were similar in all groups. After one year of treatment, hirsutism
decreased in all groups but the changes were greater (P <0.05) in the
CPA and GnRHa groups than in the Diane group. Serum LH and testosterone
were lowest in the GnRHa group. After withdrawal, hirsutism increased
rapidly in the Diane and CPA groups and after 6 months, FGL scores and hair
shaft diameters were similar to pretreatment values. In the GnRHa group,
hirsutism increased more gradually and after 1 year of withdrawal, FGL
scores and hair diameters were significantly (P <0.05) less than
pretreatment values. Serum LH and testosterone increased rapidly in all
three groups reaching pretreatment values by 6 months. These data suggest
equal efficacy of the GnRHa and the high dose CPA regimen for the treatment
of hirsutism in hyperandrogenic women. GnRHa with add-back treatment
appears to result in a longer remission of hirsutism in comparison with
CPA.
相似文献