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41.
PURPOSE: We determined whether testicular histology in men with spermatogenic failure due to nonobstructive azoospermia shows true Leydig cell hyperplasia. MATERIALS AND METHODS: Testicular biopsy specimens from 17 patients evaluated for infertility were retrospectively analyzed. Interstitial, tubular and Leydig cell volume were quantitatively evaluated. The total volume and number of Leydig cells per testicle were then calculated. RESULTS: In 10 patients with obstructive azoospermia testicular histology showed normal spermatogenic function, while 7 had nonobstructive azoospermia. Average testicular volume plus or minus standard deviation was significantly larger in those with obstructive versus nonobstructive azoospermia (18.0 +/- 7.0 versus 9.3 +/- 8.7 cc, p = 0.025). Interstitial versus tubular volume was 32% of the total testis in the obstructive and 63% in the nonobstructive groups (p = 0.003). Although Leydig cell volume was proportionally greater in men with nonobstructive versus obstructive azoospermia (13.3% versus 0.05%, p = 0.045), there was no significant difference in the average number of Leydig cells per testicle (3.96 x 10 and 6.17 x 10, respectively, p = 0.16). The average volume of individual Leydig cells was significantly greater in men with the nonobstructive condition (253.0 +/- 98.7 versus 174.0 +/- 57.7 microm., p = 0.045). CONCLUSIONS: These results suggest that men with nonobstructive azoospermia and those with normal spermatogenesis have an equivalent number of Leydig cells. However, the Leydig cells are hypertrophic and occupy a larger proportion of total testis volume in men with nonobstructive azoospermia. Therefore, patients with spermatogenic failure show Leydig cell hypertrophy but not hyperplasia.  相似文献   
42.
European Spine Journal - To determine risk factors increasing susceptibility to early complications (intraoperative and postoperative within 6 weeks) associated with surgery to correct...  相似文献   
43.
44.
Normothermic machine perfusion (NMP) has been introduced as a promising technology to preserve and possibly repair marginal liver grafts. The aim of this study was to compare the effect of temperature on the preservation of donation after cardiac death (DCD) liver grafts in an ex vivo perfusion model after NMP (38.5°C) and subnormothermic machine perfusion (SNMP, 21°C) with a control group preserved by cold storage (CS, 4°C). Fifteen porcine livers with 60 min of warm ischemia were preserved for 10 h by NMP, SNMP or CS (n = 5/group). After the preservation phase all livers were reperfused for 24 h in an isolated perfusion system with whole blood at 38.5°C to simulate transplantation. At the end of transplant simulation, the NMP group showed significantly lower hepatocellular enzyme level (AST: 277 ± 69 U/L; ALT: 22 ± 2 U/L; P < 0.03) compared to both SNMP (AST: 3243 ± 1048 U/L; ALT: 127 ± 70 U/L) and CS (AST: 3150 ± 1546 U/L; ALT: 185 ± 97 U/L). There was no significant difference between SNMP and CS. Bile production was significantly higher in the NMP group (219 ± 43 mL; P < 0.01) compared to both SNMP (49 ± 84 mL) and CS (12 ± 16 mL) with no significant difference between the latter two groups. Histologically, the NMP livers showed preserved cellular architecture compared to the SNMP and CS groups. NMP was able to recover DCD livers showing superior hepatocellular integrity, biliary function, and microcirculation compared to SNMP and CS. SNMP showed some significant benefit over CS, yet has not shown any advantage over NMP.  相似文献   
45.
Alcoholic liver disease (ALD) is the second most common indication for liver transplantation (LT). The utility of fixed intervals of abstinence prior to listing is still a matter of discussion. Furthermore, post‐LT long‐term observation is challenging, and biomarkers as carbohydrate‐deficient transferrin (CDT) may help to identify alcohol relapse. We retrospectively analyzed data from patients receiving LT for ALD from 1996 to 2012. A defined period of alcohol abstinence prior to listing was not a precondition, and abstinence was evaluated using structured psychological interviews. A total of 382 patients received LT for ALD as main (n = 290) or secondary (n = 92) indication; median follow‐up was 73 months (0–213). One‐ and five‐year patient survival and graft survival rates were 82% and 69%, and 80% and 67%, respectively. A total of 62 patients (16%) experienced alcohol relapse. Alcohol relapse did not have a statistically significant effect on patient survival (P = 0.10). Post‐transplant CDT measurements showed a sensitivity and specificity of 84% and 85%, respectively. In conclusion, this large single‐center analysis showed good post‐transplant long‐term results in patients with ALD when applying structured psychological interviews before listing. Relapse rates were lower than those reported in the literature despite using a strict definition of alcohol relapse. Furthermore, post‐LT CDT measurement proved to be a useful supplementary tool for detecting alcohol relapse.  相似文献   
46.

Background

Sentinel lymph node biopsy (SLNB) allows for staging of the axillary node status in early-stage breast cancer (BC) patients and avoiding complete axillary lymph node dissection (ALND) when the sentinel lymph node (SLN) is proven to be free of disease. In a previous randomized trial we compared SLNB followed by ALND (ALND arm) with SLNB followed by ALND only if the SLN presented metastasis (SLNB arm). At a mid-term of ≈ 6 years median follow-up, the two strategies appeared to ensure similar survival and locoregional control. We have revised these previous findings and update the results following a 15-year observation period.

Methods

Patients were randomly assigned to either the ALND or SLNB arm. The main endpoints were event-free survival (EFS), overall survival (OS), and axillary disease recurrence. EFS and OS were assessed using Kaplan–Meier analysis and the log-rank test.

Results

The ALND and SLNB arms included 115 and 110 patients, respectively. At 14.3 years median follow-up, 39 primary BC-related recurrences occurred, 22 (19 %) of which occurred in the ALND arm and 17 (16 %) occurred in the SLNB arm (p = 0.519). No axillary relapse developed in the SLNB arm, while two were observed in the ALND arm. OS (82.0 vs. 78.8 %) and EFS (72.8 vs. 72.9 %) were not statistically different between the ALND and SLNB arms (p = 0.502 and 0.953, respectively).

Conclusions

SLNB is a safe and efficacious component of the surgical treatment of early-stage BC patients. In the long-term, SLNB is equivalent to ALND in terms of locoregional nodal disease control and survival in this subset of patients.
  相似文献   
47.
We present here a multigravida patient who presented with a huge neck swelling, severe respiratory distress together with dysphagia and hoarseness of voice while she was pregnant +/- 30 weeks of gestation. She was diagnosed as an aggressive non-Hodgkin lymphoma of the thyroid gland. She was treated by 6 cycles of chemotherapy, with dramatic response after receiving the first cycle. She had 3 cycles of 4 chemotherapeutic agents before successful, elective and scheduled induction of labor at 36 weeks of gestation with favorable outcomes.  相似文献   
48.
BACKGROUNDContrast-induced nephropathy (CIN) is a reversible form of acute kidney injury that occurs within 48-72 h of exposure to intravascular contrast material. CIN is the third leading cause of hospital-acquired acute kidney injury and accounts for 12% of such cases. Risk factors for CIN development can be divided into patient- and procedure-related. The former includes pre-existing chronic renal insufficiency and diabetes mellitus. The latter includes high contrast volume and repeated exposure over 72 h. The incidence of CIN is relatively low (up to 5%) in patients with intact renal function. However, in patients with known chronic renal insufficiency, the incidence can reach up to 27%.AIMTo examine the association between renal enhancement pattern on non-contrast enhanced computed tomographic (CT) images obtained immediately following hepatic artery embolization with development of CIN.METHODSRetrospective review of all patients who underwent hepatic artery embolization between 01/2010 and 01/2011 (n = 162) was performed. Patients without intraprocedural CT imaging (n = 51), combined embolization/ablation (n = 6) and those with chronic kidney disease (n = 21) were excluded. The study group comprised of 84 patients with 106 procedures. CIN was defined as 25% increase above baseline serum creatinine or absolute increase ≥ 0.5 mg/dL within 72 h post-embolization. Post-embolization CT was reviewed for renal enhancement patterns and presence of renal artery calcifications. The association between non-contrast CT findings and CIN development was examined by Fisher’s Exact Test.RESULTSCIN occurred in 11/106 (10.3%) procedures (Group A, n = 10). The renal enhancement pattern in patients who did not experience CIN (Group B, n = 74 with 95/106 procedures) was late excretory in 93/95 (98%) and early excretory (EE) in 2/95 (2%). However, in Group A, there was a significantly higher rate of EE pattern (6/11, 55%) compared to late excretory pattern (5/11) (P < 0.001). A significantly higher percentage of patients that developed CIN had renal artery calcifications (6/11 vs 20/95, 55% vs 21%, P = 0.02).CONCLUSIONA hyperdense renal parenchyma relative to surrounding skeletal muscle (EE pattern) and presence of renal artery calcifications on immediate post-HAE non-contrast CT images in patients with low risk for CIN are independently associated with CIN development.  相似文献   
49.
Experimental mouse models of bacterial skin infections that have been described show that pathogenic microorganisms can readily invade the epidermis and dermis to produce localized infections. We used an epicutaneous mouse skin infection model to determine how the level of barrier disruption by tape‐stripping correlates with persistence of Staphylococcus aureus skin colonization, concomitant induction of cutaneous inflammation and infection. Furthermore, we investigated how murine skin responds to S. aureus colonization in a physiologic setting by analysing proinflammatory cytokines and antimicrobial peptides in mouse skin. We show that previous cutaneous damage allows skin inflammation to develop and favours S. aureus persistence leading to cutaneous colonization, suggesting an interdependence of cutaneous bacteria and skin. Our study suggests that skin barrier defects favour Saureus skin colonization, which is associated with profound cutaneous inflammation.  相似文献   
50.
AIMS: To report the appearances of cornea guttata and Fuchs' endothelial dystrophy from white light confocal microscopy. METHODS: Seven eyes of four consecutive patients with cornea guttata were prospectively examined. Of the seven eyes, three also had corneal oedema (Fuchs' dystrophy). In vivo white light tandem scanning confocal microscopy was performed in all eyes. Results were compared with non-contact specular microscopy. RESULTS: Specular microscopy was precluded by corneal oedema in one eye. In the remaining six eyes, it demonstrated typical changes including pleomorphism, polymegathism, and the presence of guttae appearing as dark bodies, some with a central bright reflex. In all seven eyes, confocal microscopy revealed the presence of round hyporeflective images with an occasional central highlight at the level of the endothelium. Changes in cell morphology and size were readily appreciated. CONCLUSION: By comparison with specular microscopy, the hyporeflective images with an occasional central highlight seen on confocal microscopy are consistent with the presence of guttae. Confocal microscopy may confirm the diagnosis of cornea guttata and Fuchs' endothelial dystrophy by demonstrating the presence of guttae. This technique is especially valuable in cases of corneal oedema, where specular microscopy may fail to visualise the endothelium. However, specular microscopy should remain the method of choice to evaluate the endothelium, principally because it is easier to use.  相似文献   
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