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1.
Sex and racial predilection, social history, and histology were analyzed in a biopsy-proven adenocarcinoma of the lower esophagus/esophagogastric junction collected over a 5-year period in two teaching institutions with different patient populations. Adenocarcinoma occurred in 11% of patients with biopsy-proven esophageal cancer. The disease occurred only in males at one center, and in a 7:1 ratio of males to females at the other center. Clear racial predilection was seen, since 12 of 13 patients with adenocarcinoma of the esophagus were white, whereas less than 20% of patients with squamous carcinoma of the esophagus were white. The finding of Barrett's epithelium in eight of the 13 cases strongly supports the theory that in white males, Barrett's epithelium is a precursor lesion of adenocarcinoma of the esophagus/esophagogastric junction.  相似文献   
2.
BACKGROUND: Superficial lymphatic malformations are predominantly developmental malformations of infancy, but they may arise at any age. OBJECTIVE: To describe a patient with a late-onset superficial lymphatic malformation. METHODS: Case report and literature review. RESULTS: A 53-year-old woman was evaluated for a colored lesion that developed spontaneously on the anterior abdominal wall. The lesion was treated by surgical excision. Findings on histopathologic examination of the specimen were consistent with superficial lymphatic malformation. There was no recurrence of the lesion at 4 months after the operation. CONCLUSION: Superficial lymphatic malformations can develop in adults spontaneously without the presence of any predisposing condition. Because the majority of such late-onset malformations reported in the literature are localized lesions similar to the one in our patient, surgical removal with inclusion of subcutaneous tissue usually results in cure without recurrence.  相似文献   
3.
BACKGROUND: We aimed to determine whether serum concentrations of anti-Müllerian hormone (AMH) can be used as a tool for prediction of the efficacy of sperm retrieval. METHODS: This was a prospective cohort observational study. AMH levels were determined in 47 men presenting for infertility evaluation. Group 1 consisted of 24 infertile patients diagnosed with non-obstructive azoospermia. Group 1 was further divided into two subgroups. The patients with spermatozoa in their testicular samples constituted group 1a (n = 13), while the patients with absence of spermatozoa constituted group 1b (n = 11). Twenty-three normozoospermic fertile men constituted group 2. Serum AMH was measured before obtaining testicular specimens. RESULTS: Testicular spermatozoa were recovered in 13 out of the 24 patients (54%). Demographic characteristics of the three groups were similar. The difference between serum AMH levels among the three groups did not reach statistical significance. CONCLUSIONS: We speculated that although AMH is secreted predominantly into the seminiferous tubules, studying serum samples might be more advantageous than seminal plasma because the presence of seminal proteases could influence AMH levels in the latter. However, our results did not demonstrate differences in serum concentrations of AMH between the studied groups. Studies with extended patient populations focusing on seminal plasma concentrations of AMH are warranted.  相似文献   
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Vascular smooth muscle cells (VSM) are normally exposed to transmural fluid flow shear stresses, and after vascular injury, blood flow shear stresses are imposed upon them. Since Ca2+ is a ubiquitous intracellular signaling molecule, we examined the effects of fluid flow on intracellular Ca2+ concentration in rat aortic smooth muscle cells to assess VSM responsiveness to shear stress. Cells loaded with fura 2 were exposed to steady flow shear stress levels of 0.5–10.0 dyn/cm2 in a parallel-plate flow chamber. The percentage of cells displaying a rise in cytosolic Ca2+ ion concentration ([Ca2+]i) increased in response to increasing flow, but there was no effect of flow on the ([Ca2+]i) amplitude of responding cells. Addition of Gd3+ (10 M) or thapsigargin (50 nM) significantly reduced the percentage of cells responding and the response amplitude, suggesting that influx of Ca2+ through ion channels and release from intracellular stores contribute to the rise in ([Ca2+]i) in response to flow. The addition of nifedipine (1 or 10 M) or ryanodine (10 M) also significantly reduced the response amplitude, further defining the role of ion channels and intracellular stores in the Ca2+ response. © 2002 Biomedical Engineering Society. PAC2002: 8716Uv, 8719Uv, 8716Dg, 8719Ff  相似文献   
6.
BACKGROUND: Patients with allergic rhinitis and bronchial hyperresponsiveness (BHR) may be at higher risk of developing asthma. OBJECTIVE: To investigate whether reactivity to aeroallergens in skin prick testing (SPT) and serum eosinophil cationic protein levels can be used to predict BHR in allergic rhinitis patients. METHODS: Fifty-nine consecutive patients with allergic rhinitis underwent SPTs using grass, tree, weed, parietaria, Alternaria, Aspergillus, mites, and cat and dog dander extracts. Methacholine challenge tests were performed using spirometry. RESULTS: Methacholine-induced BHR was detected in 23 patients (39%). Of 59 patients, 14 had 1 positive SPT response, 35 had 2 to 4 positive responses, and 10 had more than 4 positive responses. There was a significant inverse correlation between methacholine provocation concentration that caused a decrease in forced expiratory volume in 1 second of 20% (PC20) and the number of positive SPT responses (r = -0.28; P = .03). The BHR-positive patients had a mean of 4 positive SPT responses, whereas BHR-negative patients had a mean of 2.6 (P = .04). Nine BHR-positive patients (39%) and only 1 BHR-negative patient (3%) had more than 4 positive SPT responses (P < .001). There was no correlation between serum eosinophil cationic protein levels and methacholine PC20 doses. There was a strong association between hyperresponsiveness to methacholine and both cat and dog dander sensitivity (P < .001 and P = .001, respectively). CONCLUSIONS: Allergic rhinitis patients with SPT responses to a higher number of allergens are more likely to have BHR. Whether the number of positive SPT responses correlates with the risk of developing asthma in allergic rhinitis patients remains to be determined.  相似文献   
7.
PurposeThis study aimed to evaluate the effects of not using a drain or placing a drain in the glenohumeral (GH) or subacromial (SA) joint spaces on fluid retention and pain in the early postoperative period and late clinical outcomes.MethodsPatients who underwent arthroscopic rotator cuff repair between 2018 and 2020 were included in the study. Before the operation, demographic data, range of motion (ROM), visual analog scale (VAS) scores, Constant–Murley scores has documented. Deltoid muscle diameter (DMD) were measured. The total amount of irrigation used during the surgery and the operation duration were recorded, and the active amount of fluid coming from the drain in patients with a drain was recorded. The first postoperative DMD measure was made in the operating room and accepted as day 0. DMD measurements repeated postoperative first and second day. VAS assessments were performed on the postoperative first and second days. At the outpatient clinic, these measurements were repeated on the first and second weeks after discharge. Functional evaluations were made with ROM and Constant–Murley scores at the final follow-up examination.ResultsThere was no difference in the amount of drainage between the two groups in which a drain was used. When the three groups were compared among themselves regarding preoperative and postoperative VAS scores, Constant–Murley scores, and DMD, no significant difference was found.ConclusionsWe do not recommend the routine use of drains after arthroscopic rotator cuff surgery in terms of cost-effectiveness.Level of evidenceLevel II: Prospective Cohort Study.  相似文献   
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9.
By comparing the incidence of cystoid macular edema (CME) in three groups of patients having different surgical procedures, we attempted to assess the role of vitreous loss as a risk factor for CME development. In the first group (n = 470), the surgical procedure was extracapsular cataract extraction followed by implantation of posterior chamber lens (EC-CE + PC-IOL). The second group (n = 42) had extracapsular cataract extraction which was complicated by posterior capsule rupture, and therefore anterior vitrectomy followed by implantation of anterior chamber lens had to be performed (ECCE + anterior vitrectomy + AC-IOL). In the third group (n = 22) the surgery was intracapsular cataract extraction followed by anterior chamber lens implantation (ICCE + AC-IOL). The third group was included in this follow up study to assess the role of AC-IOL as a possible causative factor for development of CME in uncomplicated cases of ICCE and AC-IOL. The difference of incidences of CME in the second and third group would therefore depend mostly on the vitreous loss. The incidence of CME diagnosed by fluorescein angiography in the first, second and third group was 1.5% (7/470), 35.7% (15/42) and 9.0% (2/22), respectively. All patients who developed CME were treated with combination of corticosteroid-antibiotic drops, dexamethasone retrobulbarly (40 mg/day) and peroral indomethacine (25 mg/day/6 weeks). This therapeutic regime resulted in only moderate improvement of visual acuity.Abbreviations AC-IOL anterior chamber intraocular lens - CME cystoid macular edema - ECCE extracapsular cataract extraction - ICCE intracapsular cataract extraction - IOL intraocular lens - PC-IOL posterior chamber intraocular lens  相似文献   
10.
Abstract Background: Hypoxic-ischemic encephalopathy (HIE) is still a very important cause of neonatal mortality and morbidity. Recently platelet-activating factor (PAF) has been accused of being responsible for the neuronal damage in hypoxic-ischemic brain.
Methods: Therefore, we conducted a study in newborns with perinatal asphyxia to try to show the relationship between the clinical severity and plasma PAF levels.
Results: Mean plasma levels of 19 asphyxiated infants (997.8 ± 363.5 pg/mL) were significantly higher than that of 20 healthy infants (410.2 ± 148.6 pg/mL, P< 0.0001). Patients with clinically severe HIE had significantly higher levels of PAF (1494.2 ± 386.6 pg/mL) when compared with patients with mild HIE (815 ± 114.5 pg/mL) and with moderate HIE (828.3 ± 61.1 pg/mL). There was a significant correlation between plasma PAF concentration and arterial pH and base deficit, but no correlation with platelet and leukocyte counts.
Conclusions: Plasma PAF levels correlating with the severity of HIE is interpreted to mean that high PAF levels may be an indicator of clinical severity and probably the poorer prognosis of patients with HIE.  相似文献   
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