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91.
A proportion of men are infertile despite having normal medical history/physical examination and normal semen analysis. We aimed to assess whether normal sperm parameters per se account for male factor fertility. 1,957 infertile men were compared with 103 age-comparable fertile controls. Semen analysis was based on 2010 World Health Organization reference criteria. Of all, 12.1% of infertile men and 40.8% of fertile men presented with normal sperm parameters. Among fertile men, 36.9% had isolated sperm abnormalities and 22.3% men showed two or more concomitant sperm abnormalities. Serum total testosterone was higher in infertile men with normal sperm parameters compared to those with ≥2 sperm abnormalities or azoospermia, but similar to those with isolated sperm abnormalities (p ≤ .001). Circulating hormones were similar among sperm parameters groups in fertile men. At multivariable analyses, testicular volume (OR 1.12, p ≤ .001) and FSH (OR 0.8, p ≤ .001) were associated with normal sperm parameters. Overall, the longer the infertility period, the greater the number of sperm parameters abnormalities (p < .01). In conclusion, we found that 12% of infertile men and only 41% of fertile men present with normal sperm parameters. Normal sperm parameters per se do not reliably account for fertility in the real-life setting.  相似文献   
92.
BACKGROUND: Neutrophils are the predominant phagocytes in the early stages of myocardial ischemia-reperfusion response and are also implicated in the development of tissue damage. This study examined the role of recruited macrophages in the evolution of this tissue injury. METHODS: Farm pigs were subjected to 30 minutes of myocardial ischemia followed by 30 minutes of reperfusion. Biopsy samples were taken from the control, ischemic, and ischemic-reperfused left ventricle wall and processed for both morphologic and biochemical analyses. In situ production of tumor necrosis factor-alpha was evaluated by Western blot and immunofluorescence. A full hemodynamic evaluation was also performed. RESULTS: Myocardial ischemia and early reperfusion caused marked neutrophil and macrophage tissue accumulation and tumor necrosis factor-alpha production by the injured tissue. Immunofluorescence studies allowed us to localize tumor necrosis factor-alpha predominantly in tissue-infiltrating macrophages. No depression in the global myocardial contractile function was observed, either during ischemia or after reperfusion. CONCLUSIONS: These data suggest that the newly recruited macrophages within the ischemic and early post-ischemic myocardium may play a role in promoting neutrophil tissue infiltration and subsequent neutrophil-induced tissue dysfunction by producing tumor necrosis factor-alpha.  相似文献   
93.
94.
Sophisticated and newer imaging capabilities have resulted in increased reporting and treatment options of spinal lumbar synovial cysts (LSS). Most of the patients with lumbar cysts tend to be in their sixth decade of life with a slight female predominance. The incidence of LSS is thought to be less than 0.5% of the general symptomatic population. They may be asymptomatic and found incidentally or the epidural growth of cysts into the spinal canal can cause compression of neural structures and hence associated clinical symptoms. Most of the symptomatic LSS patients present with radicular pain and neurological deficits. Spinal synovial cysts are commonly found at L4-5 level, the site of maximum mobility. They may be unilateral or bilateral and at one or multilevel. MRI is considered the tool of choice for its diagnosis. The etiology of LSS is still unclear, but underlying spinal instability, facet joint arthropathy and degenerative spondylolisthesis has a strong association for worsening symptoms and formation of spinal cysts. Synovial cysts resistant to conservative therapy should be treated surgically. Resection and decompression with or without fusion and instrumentation remains an appropriate option. Synovial cysts may recur following surgery. The optimal approach for patients with juxtafacet LSS remains unclear. The best surgical treatment option for each particular individual should be tailored depending upon the symptoms, radiological findings and other co morbidities.  相似文献   
95.
Out of 210 children suffering from severely displaced supracondylar fractures, 76 (36%) presented with immediate neurovascular complications: 47 (22%) were neurological, 16 (8%) vascular and 13 (6%) both. Injury to two nerves simultaneously was observed in six patients. The median nerve was affected in 28 cases, the ulnar nerve in 25 and the radial nerve in 13. Posterolateral displacement was associated with 86% of damage to the median nerve and 56% of damage to the ulnar nerve. Posteromedial displacement was associated with all incidents of injury to the radial nerve with one exception. Each patient made full neurological recovery, spontaneously and following primary or secondary neurolysis performed on nerve injuries in continuity. Two situations of primary abolition of the radial pulse were encountered, one involving a pink hand in 12.5% of cases and the other involving a white hand in 1.5% of cases. There was posterolateral displacement in three out of four patients. Postoperative vascularization was revealed by immediate return of the radial pulse in 26 patients and delayed return in three others. Urgent anatomical reduction of the fracture and its early fixation are crucial. A conservative therapeutic approach is customary in the majority of neurovascular complications. Prognosis is generally excellent. Ischaemia of the limb and total ruptures of the nerve are very rare.  相似文献   
96.
To quantify the effects of facial palsy reanimation, 14 patients aged 17–66 years were analysed. All patients had unilateral facial paralysis, and were candidates for surgical masseteric to facial nerve anastomosis. Two patient groups were measured: seven patients were waiting for surgery, the other seven patients had already been submitted to surgery, and had regained facial mimicry. Each patient performed three facial animations: brow raise; free smile; lip purse. These were recorded using an optoelectronic motion analyser.The three-dimensional coordinates of facial landmarks were obtained, their movements were computed, and asymmetry indices calculated (differential movements between the two hemi-faces: healthy and paretic/rehabilitated). Before surgery, mobility was larger in the healthy than in the paretic side; after surgery, the differences were reduced (brow raise and lip purse), or even reversed (smile). Before surgery, lip purse was performed with significant labial asymmetry (p = 0.042; larger healthy side movement). After surgery, asymmetry indices reduced. Total labial asymmetry during smiling was significantly different from 0 before surgery (p = 0.018, larger healthy side movement). After surgery, all asymmetry indices became non-significant. Before surgery the lateral displacements of all labial landmarks were towards the healthy side, while they normalized after surgery.  相似文献   
97.
While during the first trimester of pregnancy natural killer (NK) cells represent the most abundant lymphocyte population in the decidua, their actual function at this site is still debated. In this study we analyzed NK cells isolated from decidual tissue for their surface phenotype and functional capability. We show that decidual NK (dNK) cells express normal surface levels of certain activating receptors, including NKp46, NKG2D, and 2B4, as well as of killer cell immunoglobulin-like receptors (KIRs) and CD94/NKG2A inhibitory receptor. In addition, they are characterized by high levels of cytoplasmic granules despite their CD56(bright) CD16- surface phenotype. Moreover, we provide evidence that in dNK cells, activating NK receptors display normal triggering capability whereas 2B4 functions as an inhibitory receptor. Thus, cross-linking of 2B4 resulted in inhibition of both cytolytic activity and interferon-gamma (IFN-gamma) production. Clonal analysis revealed that, in the majority of dNK cell clones, the 2B4 inhibitory function is related to the deficient expression of signaling lymphocyte activation molecule (SLAM)-associated protein (SAP) mRNA. Moreover, biochemical analysis revealed low levels of SAP in the dNK polyclonal population. This might suggest that dNK cells, although potentially capable of killing, are inhibited in their function when interacting with cells expressing CD48.  相似文献   
98.
Follicular lymphoma international prognostic index   总被引:14,自引:14,他引:14       下载免费PDF全文
The prognosis of follicular lymphomas (FL) is heterogeneous and numerous treatments may be proposed. A validated prognostic index (PI) would help in evaluating and choosing these treatments. Characteristics at diagnosis were collected from 4167 patients with FL diagnosed between 1985 and 1992. Univariate and multivariate analyses were used to propose a PI. This index was then tested on 919 patients. Five adverse prognostic factors were selected: age (> 60 years vs 60 years), Ann Arbor stage (III-IV vs I-II), hemoglobin level (< 120 g/L vs 120 g/L), number of nodal areas (> 4 vs 4), and serum LDH level (above normal vs normal or below). Three risk groups were defined: low risk (0-1 adverse factor, 36% of patients), intermediate risk (2 factors, 37% of patients, hazard ratio [HR] of 2.3), and poor risk ( 3 adverse factors, 27% of patients, HR = 4.3). This Follicular Lymphoma International Prognostic Index (FLIPI) appeared more discriminant than the International Prognostic Index proposed for aggressive non-Hodgkin lymphomas. Results were very similar in the confirmation group. The FLIPI may be used for improving treatment choices, comparing clinical trials, and designing studies to evaluate new treatments.   相似文献   
99.
100.
PURPOSE: To investigate changes in the prevalence of visual impairment in an Italian population from 1988 to 2000. METHODS: Standardized ophthalmologic examinations were administered to citizens of Ponza, Italy aged 40-87 years in 1988 and 2000. Visual Acuity (VA) was measured using a standard logarithmic chart. Visual fields (VF) were tested in all subjects with diagnosed or suspected glaucoma or hereditary degenerative retinopathy. Visual impairment was classified as blindness (VA > 1.3 LogMAR or VF < 10 degrees around central fixation) or low vision (VA > 0.5 to 1.3 LogMAR or VF < 20 degrees to 10 degrees) according to WHO criteria. RESULTS: The prevalence of binocular total visual impairments decreased significantly among 64-75 year-olds (from 6.7% to 2.6%, p = 0.045), and almost significantly among 40-51 year-olds (from 2.4%, 95% CI 1.1-5.3, to 0.0%, 95% CI 0.0-1.3). By 2000, visual impairment was no longer significantly associated with female gender, and age 64-75 years; the mean age of subjects with vision-impairing cataract, diabetic retinopathy, or age-related macular degeneration had risen significantly. CONCLUSIONS: A decline in the prevalence of visual impairment, particularly in cataract-associated visual impairment was found in the middle-aged groups. The progression of age-related eye diseases seems to have slowed in this population possibly due to improvements in the life expectancy and socio-economic conditions.  相似文献   
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