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41.
Methods of exposing impacted teeth in order to bring them into the line of the arch include gingivectomy, the apically repositioned flap and closed eruption techniques. These procedures aim to facilitate the eruption of the impacted tooth with a minimum of disruption or damage to the tooth itself or adjacent structures. The aim of this paper is to discuss the various surgical methods of exposing impacted teeth and to help to identify where the use of the apically repositioned flap is indicated. Clinical examples are presented and a surgical method for carrying out this procedure recommended. 相似文献
42.
Malek AM Halbach VV Phatouros CC Higashida RT Dowd CF Wachhorst S Lawton MT 《Neurosurgery》1999,44(4):877-880
OBJECTIVE AND IMPORTANCE: A case of a spinal dural arteriovenous fistula (DAVF) with two associated feeding artery aneurysms is reported. Intradural spinal arteriovenous malformations have been associated with aneurysms that present with subarachnoid hemorrhage and with venous varices that produce mass effect, but spinal DAVFs have not previously been described in association with feeding artery aneurysms. CLINICAL PRESENTATION: A 71-year-old man presented with progressive spastic paraparesis, constipation, and overflow incontinence. Magnetic resonance imaging demonstrated a spinal vascular lesion and venous ischemia in the lower spinal cord. Diagnostic spinal angiography revealed a DAVF originating from the left T11 radicular artery and having the unusual feature of two proximal feeding artery aneurysms. INTERVENTION: The patient deteriorated neurologically after undergoing angiography, prompting emergent surgery. The DAVF was resected through a T11 transpedicular approach. One aneurysm was dolichoectatic and therefore unclippable, requiring proximal occlusion of the parent artery after establishing tolerance of test occlusion using somatosensory evoked potentials; the second aneurysm was adjacent to the fistula and was resected with the DAVF. CONCLUSION: Feeding artery aneurysms in association with spinal DAVFs have not been previously reported. They present additional risk to patients and, with simple modifications of the standard operative approaches, can easily be treated as part of the surgery for the DAVF. 相似文献
43.
Goldstein SM Syed NA Milam AH Maguire AM Lawton TJ Nichols CW 《Arch. Ophthalmol.》1999,117(12):1641-1645
Patients with systemic cancer may have a variety of ocular complaints. Most commonly these are metastases or adverse effects of therapy. Paraneoplastic syndromes, like cancer-associated retinopathy, rarely cause ophthalmic symptoms. We describe a patient with a malignant mixed mullerian tumor and cancer-associated retinopathy who had circulating serum antibodies to recoverin and cells positive for recoverin in the tumor. We discuss the typical clinical symptoms as well as the pathophysiology of this uncommon disorder. 相似文献
44.
45.
Immunological function were studied in 22 patients with hydatidiform mole and 29 patients with malignant trophoblastic disease before and after treatment; normal pregnant and post-pregnant women served as controls. The only significant abnormality in hydatidiform mole was a low granulocyte chemotaxis before evacuation. In malignant trophoblastic disease the total lymphocyte counts, T-cell counts. B-cell counts, lymphocyte responses to mitogens and serum IgA levels were significantly lower than in normal women 6 wk after pregnancy. In those who responded to chemotherapy, these indices rose to the levels of post-pregnancy controls. An 'immune profile score' based on these indices was found to be a useful prognostic index. All patients with hydatidiform mole who had a score of 7 or less developed malignant trophoblastic disease, while the two patients with malignant trophoblastic disease who died had the lowest scores of the series. 相似文献
46.
Esophagogastrectomy for adenocarcinoma of the cardia. Ten years' experience and current approach. 总被引:4,自引:2,他引:2 下载免费PDF全文
During a 10-year period, 94 surgical resections for adenocarcinoma of the cardia (75 "curative" and 19 palliative) were performed using three primary approaches: Group I (46 curative, 14 palliative), esophagogastrectomy performed through a left thoracotomy or left thoraco-abdominal incision; Group II (17 curative, 4 palliative), resection done through two separate incisions (abdominal and thoracic) with delayed reconstruction between two and three months later; and Group III (12 curative, 1 palliative), resection, also through abdominal and thoracic incisions, with simultaneous reconstruction. Operative mortality in the 75 procedures done for cure was 19.5%, 18%, and 8.3% in Groups I, II, and III, respectively. Microscopic residual tumor at the line of resection was 56%, 12%, and 8%. Free margins less than 3 cm had the same local recurrence rate (21%, 6%, and 8%) within 18 months as did margins with residual microscopic tumor. The length of time from operation to first regular meal was 12, 110, and 7 days, respectively. Wide resection with subtotal esophagectomy and simultaneous reconstruction is advocated. 相似文献
47.
M Roach M DeSilvio C Lawton V Uhl M Machtay M J Seider M Rotman C Jones S O Asbell R K Valicenti S Han C R Thomas W S Shipley 《Journal of clinical oncology》2003,21(10):1904-1911
PURPOSE: This trial tested the hypothesis that combined androgen suppression (CAS) and whole-pelvic (WP) radiotherapy (RT) followed by a boost to the prostate improves progression-free survival (PFS) by 10% compared with CAS and prostate-only (PO) RT. This trial also tested the hypothesis that neoadjuvant and concurrent hormonal therapy (NCHT) improves PFS compared with adjuvant hormonal therapy (AHT) by 10%. MATERIALS AND METHODS: Eligibility included localized prostate cancer with an elevated prostate-specific antigen (PSA) < or = 100 ng/mL and an estimated risk of lymph node (LN) involvement of 15%. Between April 1, 1995, and June 1, 1999, 1,323 patients were accrued. Patients were randomly assigned to WP + NCHT, PO + NCHT, WP + AHT, or PO + AHT. Failure for PFS was defined as the first occurrence of local, regional, or distant disease; PSA failure; or death for any cause. RESULTS: With a median follow-up of 59.5 months, WP RT was associated with a 4-year PFS of 54% compared with 47% in patients treated with PO RT (P =.022). Patients treated with NCHT experienced a 4-year PFS of 52% versus 49% for AHT (P =.56). When comparing all four arms, there was a progression-free difference among WP RT + NCHT, PO RT + NCHT, WP RT + AHT, and PO RT + AHT (60% v 44% v 49% v 50%, respectively; P =.008). No survival advantage has yet been seen. CONCLUSION: WP RT + NCHT improves PFS compared with PO RT and NCHT or PO RT and AHT, and compared with WP RT + AHT in patients with a risk of LN involvement of 15%. 相似文献
48.
Gerald E Hanks Thomas F Pajak Arthur Porter David Grignon Harmart Brereton Varagur Venkatesan Eric M Horwitz Colleen Lawton Seth A Rosenthal Howard M Sandler William U Shipley 《Journal of clinical oncology》2003,21(21):3972-3978
PURPOSE: Radiation Therapy Oncology Group (RTOG) Protocol 92-02 was a randomized trial testing long-term (LT) adjuvant androgen deprivation (AD) after initial AD with external-beam radiotherapy (RT) in patients with locally advanced prostate cancer (PC; T2c-4) and with prostate-specific antigen level less than 150 ng/mL. PATIENTS AND METHODS: Patients received a total of 4 months of goserelin and flutamide, 2 months before and 2 months during RT. A radiation dose of 65 to 70 Gy was given to the prostate and a dose of 44 to 50 Gy to the pelvic lymph nodes. Patients were randomly assigned to receive no additional therapy (short-term [ST]AD-RT) or 24 months of goserelin (LTAD-RT); 1,554 patients were entered onto the study. RESULTS: The LTAD-RT arm showed significant improvement in all efficacy end points except overall survival (OS; 80.0% v 78.5% at 5 years, P =.73), compared with the STAD-RT arm. In a subset of patients not part of the original study design, with tumors assigned Gleason scores of 8 to 10 by the contributing institutions, the LTAD-RT arm had significantly better OS (81.0% v 70.7%, P =.044). There was a small but significant increase in the frequency of late radiation grades 3, 4, and 5 gastrointestinal toxicity ascribed to the LTAD-RT arm (2.6% v 1.2% at 5 years, P =.037), the cause of which is not clear. CONCLUSION: The RTOG 92-02 trial supports the addition of LT adjuvant AD to STAD with RT for T2c-4 PC. In the exploratory subset analysis of patients with Gleason scores 8 to 10, LT adjuvant AD resulted in a survival advantage. 相似文献
49.
OBJECTIVES: To study the efficacy of otoacoustic emissions (OAEs) as a screening test for hearing impairment in children with acute bacterial meningitis. Hearing tests were performed before discharge from the hospital in an attempt to improve coverage and avoid delays in the diagnosis of postmeningitic hearing loss. METHODS: Children with bacterial meningitis were recruited from 21 centers. In the 48 hours before discharge from the hospital, all patients underwent a thorough audiologic assessment consisting of transient evoked OAEs, auditory brainstem responses (ABRs), otoscopy, and tympanometry. Hearing loss was defined as ABR threshold >/=30 dB. The results of OAE screening were compared with the gold standard of ABR threshold. RESULTS: Of 124 children recruited, we were able to perform both OAEs and ABRs on 110 children. Seven (6.3%) of the 110 children had ABR threshold >/=30 dB; 2 had sensorineural hearing loss and 5 had conductive hearing loss. At follow-up, hearing loss persisted in both cases of sensorineural hearing loss and no new cases were identified. All 7 children with hearing loss failed the OAE screening test. Ninety-four children with normal hearing thresholds passed the test, and 9 failed. Thus, the screening test had a sensitivity of 1.00 (95% confidence interval, 0.59 to 1.00), a specificity of 0.91 (0.85 to 0.97), a positive predictive value of 0. 44 (0.20 to 0.70), and a negative predictive value of 1.00 (0.96 to 1.00). CONCLUSIONS: OAE screening in children recovering from meningitis was found to be feasible and effective. The test was highly sensitive and reasonably specific. Inpatient OAE screening should allow early diagnosis of postmeningitic hearing loss and prompt auditory rehabilitation. 相似文献
50.
Iron-overload diseases frequently develop hepatocellular carcinoma. The
genotoxic mechanism whereby iron is involved in hepatocarcinogenesis might
involve an oxidative process via the intermediate production of reactive
oxygen species. This was presently investigated by examining kinetics of
formation and repair of DNA base lesions in primary rat hepatocyte cultures
supplemented with the iron chelate, ferric nitrilotriacetate Fe-NTA (10 and
100 microM). Seven DNA base oxidation products have been identified in DNA
extracts by gas chromatography- mass spectrometry, which showed a
predominance of oxidized-purines (8- oxo-guanine, xanthine, fapy-adenine,
2-oxo-adenine) above oxidized pyrimidines (5-OHMe-uracil, 5-OH-uracil,
5-OH-cytosine) in control cultures. All these DNA oxidation products
revealed a significant dose- dependent increase at 4 to 48 h after Fe-NTA
supplementation, among which fapy-adenine showed the highest increase and
5-OH-cytosine was the least prominent. Involvement of iron in this
oxidative process was established by a correlation between extent in DNA
oxidation and intracellular level of toxic low molecular weight iron. DNA
excision- repair activity was estimated by release of DNA oxidation
products in culture medium. All the seven DNA oxidation products were
detected in the medium of control cultures and showed basal repair
activity. This DNA repair activity was increased in a time- and
dose-dependent fashion with Fe-NTA. Oxidized-pyrimidines, among which was
5-OHMe-Uracil, were preferentially repaired, which explains the low levels
detected in oxidized DNA. Since oxidized bases substantially differed from
one another in terms of excision rates from cellular DNA, specific
excision- repair enzymes might be involved. Our findings, however,
demonstrate that even though DNA repair pathways were activated in
iron-loaded hepatocyte cultures, these processes were not stimulated enough
to prevent an accumulation of highly mutagenic DNA oxidative products in
genomic DNA. The resulting genotoxic effect of Fe-NTA might be relevant in
understanding the hepatocarcinogenic evolution of iron-overload diseases.
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