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1.
Objective: The options available for the treatment of a nonsecreting pituitary macroadenoma that has been incompletely resected include reoperation, fractionated radiation therapy, and radiosurgery. Reoperation in this setting may be hindered by the same obstacles that prevented a complete resection during the initial surgical procedure, and should prompt consideration of an alternate approach or exposure. Methods: Between January 1998 and December 2003, 10 consecutive patients were referred to the Department of Neurosurgery at the University of Texas Southwestern Medical Center for the evaluation of a nonsecreting pituitary macroadenoma that measured 3 cm or greater in diameter despite having undergone an attempt at a complete resection elsewhere. Each of these patients was reoperated using a Le Fort I maxillotomy to enhance the exposure provided by a traditional transsphenoidal approach. Results: A total or near total (> 95%) resection was achieved in each case. One patient required reoperation for the repositioning of a fat graft to treat a cerebrospinal fluid fistula and one patient experienced a worsening of anterior pituitary function postoperatively. Five patients noted improved vision and no patient experienced further visual loss. Three patients have required subsequent treatment of small foci of recurrent or progressing tumor with stereotactic radiation therapy. No patient has received fractionated radiation therapy. Conclusion: The added exposure provided by a Le Fort I maxillotomy facilitates the resection of pituitary macroadenomas that have been incompletely resected by a traditional transnasal, trans-sphenoidal approach.  相似文献   
2.

Background  

Experimental studies have shown that positron emission tomography (PET) with 13N-labeled ammonia provides accurate quantification of regional myocardial blood flow (MBF) under rest and stress conditions. To establish the clinical utility of this method, the interobserver variability and the temporal variability of serial measurements of blood flow and coronary flow reserve (CFR) must be known. This study investigated the interobserver and temporal reproducibility of 13N-labeled PET for measurement of MBF and CFR.  相似文献   
3.
Standard treatment for advanced rectal carcinoma currently includes surgery, radiotherapy, and chemotherapy. Although there are theoretic advantages to preoperative irradiation, it is often not performed because of the prolonged delay of surgery and the purported increase in perioperative complications. A pilot study was undertaken at our institution to evaluate a treatment protocol advocated by Dr. Papillon that offers a shorter treatment time and less patient morbidity than conventional preoperative therapy for rectal carcinoma. Twenty patients with rectal cancer underwent the preoperative regimen that consisted of 3,000 cGy delivered in 10 fractions over 12 days with concomitant 5-fluorouracil and mitomycin-C. Complications were acceptable. Local recurrence was lower than in most reported trials, and survival rates were comparable. Additional benefits of the protocol include lower radiation morbidity to the patient and a decreased delay between diagnosis and surgery.  相似文献   
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5.
We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder.  相似文献   
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7.
Chromosome region 17q12-23 commonly shows an increase in DNA copy number in breast cancers, suggesting that several oncogenes are located at this site. We performed a high-resolution expression array and comparative genomic hybridization analysis of genes mapped to the entire 17q12-23 region, to identify novel candidate oncogenes. We identified 24 genes that showed significant overexpression in breast cancers with gain of 17q12-23, compared to cancers without gain. These genes included previously identified oncogenes, together with several novel candidate oncogenes. FISH analysis using specific gene probes hybridized to tissue arrays confirmed the underlying amplification of overexpressed genes. This high-resolution analysis of the 17q12-23 region indicates that several established and novel candidate oncogenes, including a Wnt-signaling pathway member, are amplified and overexpressed within individual primary breast cancer samples. We were also able to confirm the presence of two apparently separate and reciprocally amplified groups of genes within this region. Investigation of these genes and their functional interactions will facilitate our understanding of breast oncogenesis and optimal management of this disease.  相似文献   
8.
The pathological features of 13 cases with juxtaposition of the atrial appendages in the autopsy files of The Johns Hopkins Hospital were studied. The anomaly occurs most frequently in association with transposition of the great vessels, ventricular septal defect, patent foramen ovale, and obstructive lesions of the tricuspid and pulmonic valves. The malformation complex of tricuspid atresia, atrial and ventricular septal communication, and the transposition of the great vessels seems particularly common with juxtaposition of the atrial appendage. A recent case showed a small accessory right atrial appendage lying in juxtaposition to the left atrial appendage. In addition, a normally situated right atrial appendages in addition to well-formed accessory appendages lying in juxtaposition to the left atrial appendages. It seems that juxtaposition of the atrial appendages should be reinterpreted as an accessory appendage or atrial diverticulum.  相似文献   
9.
Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system. While its etiology is not well understood, genetic factors are clearly involved. Until recently, most genetic studies in MS have been association studies using the case-control design testing specific candidate genes and studying only sporadic cases. The only consistently replicated finding has been an association with the HLA-DR2 allele within the major histocompatibility complex (MHC) on chromosome 6. Using the genetic linkage design, however, evidence for and against linkage of the MHC to MS has been found, fostering suggestions that sporadic and familial MS have different etiologies. Most recently, two of four genomic screens demonstrated linkage to the MHC, although specific allelic associations were not tested. Here, a dataset of 98 multiplex families was studied to test for an association to the HLA-DR2 allele in familial MS and to determine if genetic linkage to the MHC was due solely to such an association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta) in the MHC demonstrated strong genetic linkage (parametric lod scores of 4.60, 2.20 and 1.24, respectively) and a specific association with the HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results by HLA-DR2 status showed that the linkage results were limited to families segregating HLA-DR2 alleles. These results demonstrate that genetic linkage to the MHC can be explained by the HLA-DR2 allelic association. They also indicate that sporadic and familial MS share a common genetic susceptibility. In addition, preliminary calculations suggest that the MHC explains between 17 and 62% of the genetic etiology of MS. This heterogeneity is also supported by the minority of families showing no linkage or association with loci within the MHC.   相似文献   
10.
Operative repair of ventricular aneurysms should improve left ventricular function. Despite its theoretic advantage, the mortality following this operation is high, and many patients have severe postoperative hypotension. The cardiac findings were studied in 18 patients who died after repair of ventricular aneurysms. All hearts were examined at autopsy after postmortem coronary arteriography and fixation in a distended state. Five patients in Group I had intractable fatal postoperative hypotension, 7 in Group II initially had severe hypotension that improved, and 6 in Group III did not have postoperative hypotension. Curvature thickness indexes (CTIs) of the ventricular segments, which correlate with their pressure-producing activity, were determined in the 18 hearts. CTIs for the left ventricular free wall and septum were lower in Group I and Group II patients with hypotension than those in Group III without. The reduced CTIs in patients with postoperative shock appear to arise as a result of ventricular reconstruction that reduces ventricular wall curvature. The authors suggest that left ventricular function after aneurysm resection would be improved by inverting, rather than everting, the edges of the ventriculotomy, thereby increasing wall curvature and the CTI. Noninvasive determinations of the CTI may prove of value in guiding topographic reconstruction of ventricles with aneurysms.  相似文献   
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