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971.
972.
BACKGROUND: The goal of this study was to examine the role of ultrasonography in detecting axillary lymph node metastases in stage II breast cancer patients after induction chemotherapy (IC). METHODS: Of 172 consecutive patients with T1-3, N0-1, M0 breast cancer registered in a prospective IC trial, a subset of 130 evaluable patients were chosen, with (1) both physical and ultrasonographic examinations of the axilla before and after IC; (2) exactly four cycles of IC; (3) no presurgical radiation therapy; and (4) an axillary lymph node dissection. RESULTS: Before IC, 32 patients (25%) were negative for axillary involvement by both physical and ultrasonographic examinations. After IC, this number increased to 64 (49%). Of these, 31 (48%) were positive by pathology examination. In most cases, however, the residual tumor was minimal. CONCLUSIONS: Stage II breast cancer patients who were or became node negative by both ultrasonographic and physical examinations after IC had a 48% incidence of nodal metastases. Because the residual tumor was minimal, irradiation may be sufficient for adequate local control of the axilla.  相似文献   
973.
It was hypothesized that peripheral arterial disease (PAD) is less frequent after kidney transplantation than among comparable patients who are on the deceased-donor waiting list. The cumulative incidences and risk factors for PAD were compared among 43,427 adult transplant recipients and 53,309 adults who were placed on the renal transplant waiting list between 1995 and 2003. All patients had Medicare primary insurance coverage, and Medicare claims were used to identify PAD. For patients with diabetes, the 3-yr cumulative incidence of de novo PAD was 24% on the waiting list versus 20% after transplantation. For patients without diabetes, the 3-yr cumulative incidence was 9% on the waiting list versus 5% after transplantation. The adjusted relative risk (RR) for PAD among patients without diabetes was 0.73 (95% confidence interval [CI] 0.66 to 0.80; P < 0.0001) in the transplant population versus the waiting list population, whereas among patients with diabetes, it was 0.88 (95% CI 0.82 to 0.96; P = 0.0024). A diagnosis of PAD on the waiting list was associated with an almost three-fold increase in the RR for death for patients without diabetes (2.98; 95% CI 2.71 to 3.27; P < 0.0001) and with diabetes (2.92; 95% CI 2.71 to 3.15; P < 0.0001). After transplantation, de novo PAD increased the RR for death almost two-fold in patients without diabetes (1.92; 95% CI 1.63 to 2.26; P < 0.0001) and with diabetes (1.83; 95% CI 1.58 to 2.12; P < 0.0001). The incidence of PAD is higher on the waiting list than after transplantation and is associated with an increased risk for death among patients with and without diabetes.  相似文献   
974.
An epidemic form of arthritis has been occurring in eastern Connecticut at least since 1972, with the peak incidence of new cases in the summer and early fall. Its identification has been possible because of tight geographic clustering in some areas, and because of a characteristic preceding skin lesion in some patients. The authors studied 51 residents of three contiguous Connecticut communities—39 children and 12 adults—who developed an illness characterized by recurrent attacks of asymmetric swelling and pain in a few large joints, especially the knee. Attacks were usually short (median: 1 week) with much longer intervening periods of complete remission (median: 2.5 months), but some attacks lasted for months. To date the typical patient has had three recurrences, but 16 patients have had none. A median of 4 weeks (range: 1–24) before the onset of arthritis, 13 patients (25%) noted an erythematous papule that developed into an expanding, red, annular lesion, as much as 50 cm in diameter. Only 2 of 159 family members of patients had such a lesion and did not develop arthritis (P < 0.000001). The overall prevalence of the arthritis was 4.3 cases per 1,000 residents, but the prevalence among children living on four roads was 1 in 10. Six families had more than 1 affected member. Nine of 20 symptomatic patients had low serum C3 levels, compared to none of 31 asymptomatic patients (P < 0.005); no patient had iridocyclitis or a positive test for antinuclear antibodies. Neither cultures of synovium and synovial fluid nor serologic tests were positive for agents known to cause arthritis. “Lyme arthritis” is thought to be a previously unrecognized clinical entity, the epidemiology of which suggests transmission by an arthropod vector.  相似文献   
975.
Berger AC  Watson JC  Ross EA  Zalatoris A  Hoffman JP 《The American surgeon》2004,70(2):169-73; discussion 173-4
Increased expression of vascular endothelial growth factor (VEGF) by pancreatic cancer correlates with poor survival. The significance of VEGF in biliary and pancreatic secretions in periampullary cancers is unknown. Bile and pancreatic juice samples were collected from patients undergoing pancreaticoduodenectomy (PD). All samples were frozen at -70 degrees C until subsequent analysis for VEGF concentration using enzyme-linked immunoabsorbent assay (ELISA). Plasma VEGF levels in pancreatic cancer patients were <10 pg/mL. The biliary VEGF concentration for patients with malignancy was significantly elevated compared to benign disease (P = 0.05). There was no difference in pancreatic VEGF concentrations between benign and malignant disease. Cancer patients undergoing preoperative chemoradiation (CRT) had lower biliary and pancreatic VEGF concentrations than those who did not. Preoperative biliary drainage (BD) was associated with decreased VEGF concentrations in bile (3500 pg/mL vs 7740 pg/mL, P = 0.027). Patients undergoing both CRT and BD had diminished biliary and pancreatic VEGF concentrations compared to those who had neither. This was statistically significant for pancreatic VEGF concentrations (917 pg/mL vs 4723 pg/mL, P = 0.044). VEGF is highly concentrated in bile and pancreatic juice compared to plasma. Preoperative CRT and BD significantly reduce these levels in patients with periampullary cancers. Antiangiogenic therapy aimed at interrupting the VEGF pathway appears to be a logical target in periampullary cancer.  相似文献   
976.
977.
neurogenetics - Monoamine neurotransmitter disorders present predominantly with neurologic features, including dystonic or dyskinetic cerebral palsy and movement disorders. Genetic conditions that...  相似文献   
978.
979.
Roughly a quarter of all clavicle fractures occur at the lateral end. Displaced fractures of the lateral clavicle have a higher rate of nonunion. The management of fractures of the lateral clavicle remains controversial. Open reduction internal fixation with a superiorly placed locking plate is a recently developed technique. However, there are no randomized controlled trials to evaluate the efficacy of this procedure. We present a series of four cases which highlight the technical drawbacks with this method of fixation for lateral clavicle fractures. Two cases show that failure of the plate to negate the displacing forces at the fracture site can lead to plate pullout. Two cases illustrate an unusual complication of an iatrogenic injury to the acromioclavicular joint capsule which led to joint instability and dislocation. We advise caution in using this method of fixation. Recent studies have described the success of lateral clavicle locking plate fixation augmented with a coracoclavicular sling. This augmentation accounts for the displacing forces at the fracture site. We would recommend that when performing lateral clavicle locking plate fixation, it should be reinforced with a coracoclavicular sling to prevent plate failure by lateral screw pullout.  相似文献   
980.
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