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排序方式: 共有558条查询结果,搜索用时 437 毫秒
1.
This study aimed to evaluate stallion sperm survival after 24 h of cooled storage in the presence of seminal plasma (SP) derived from the sperm‐rich fractions (SRF) or sperm‐poor fractions(SPF) of the ejaculate, without SP, or in the presence of SP from other stallions. Ejaculates were collected from four stallions using an automated phantom, which separated the semen into five cups. Centrifuged and washed spermatozoa from cup 2 (SRF) were mixed with skim milk extender to a concentration of 100 × 106 sperm/ml and then 1:1 (v/v) with SP from the stallion's own or another stallions’ second (SP‐SRF) or last cup (SP‐SPF). Skim milk extender (K) and skim milk extender supplemented with modified Tyrode's medium (KMT) were used as control treatments. After a 24‐h storage period in a transport container, spermatozoa were evaluated for motion characteristics and plasma membrane integrity by calcein acetoxymethyl (AM)/propidium iodide staining. The percentage of spermatozoa with intact plasma membranes after storage was lower in SP‐SRF than in SP‐SPF, and the highest in K (P < 0.05). Progressive motility (PMOT) was lower for sperm stored in SP‐SRF than for sperm stored in SP‐SPF (P < 0.05), but there was no significant difference in total motility (TMOT). Sperm stored in KMT (P < 0.05) registered the highest TMOT and PMOT percentages. Osmolarity was significantly higher and pH lower in K than in KMT or SP. Treatment with SP‐SPF from three stallions benefited the PMOT of sperm from one stallion. These preliminary findings suggest that SP from SRFs may be more harmful during storage than SP from SPFs. Removal of SP improves sperm survival in KMT extender, and exchanging SP between stallions seems to influence sperm survival.  相似文献   
2.
Laparoscopy or laparotomy for the management of endometrial cancer.   总被引:2,自引:0,他引:2  
OBJECTIVE: The aim of this study was to evaluate the feasibility of laparoscopy in the management of early stage endometrial cancer. METHODS: Fifty-two patients with endometrial cancer who underwent surgical staging consisting of total hysterectomy, bilateral salpingo-oophorectomy with pelvic lymph node dissection, and cytology between 1998 to 2002 were included in the study. Laparotomy and laparoscopy were randomly offered to patients upon admittance. RESULTS: Of 52 patients, 26 underwent laparotomy and the remaining 26 underwent laparoscopic staging surgery. No significant difference existed between the demographic characteristics of the 2 groups. The mean number of harvested lymph nodes was 18.2 in the laparoscopic group and 21.1 in the laparotomic group (P>0.05). Pelvic lymph node metastases were detected in 7.7% of the patients in the laparoscopy group and 15.4% in the laparotomy group, and the difference was not significant. Adjuvant radiotherapy was applied later to 42.3% of the laparoscopy group and 38.5% of the laparotomy group. Operative morbidity was higher in the laparotomy group mainly because of postoperative wound infection, and the patients in the laparotomy group had a longer hospital stay. CONCLUSION: Laparoscopic surgery is a method that can be applied as well as laparotomy in the management of endometrial cancer. Lymph node number and detection of lymph node metastasis did not differ significantly in laparotomic and laparoscopic approaches. Wound infections were more frequent in laparotomies.  相似文献   
3.
The spinal cord is situated within the vertebral canal by the third month of intrauterine life. The spinal cord possesses two symmetrical enlargements, which constitute the segments of the plexuses the cervical enlargement for the brachial plexus and the lumbosacral enlargement for the lumbar and sacral plexus. In our study, we aimed to investigate the relationship between the termination level of the lumbosacral enlargement (TLLE) and that of the conus medullaris (TLCM) during the period of fetal development and adulthood. We used a total of 75 cases 25 fetuses (male 16, female 9) whose crown-rump length ranged between 90–190 mm, 25 premature and full-term neonates (male 17, female 8) whose post-menstrual ages ranged between 33–55 weeks, and 25 adults (male 12, female 13) aged between 22–72 years. The dissection technique for fetuses, ultrasonography for premature and full-term newborns, and magnetic resonance imaging (MRI) for adults were used to determine lumbosacral enlargement and TLCM. The differences between the TLCM and the termination level of the largest part of the transverse diameter of the lumbosacral enlargement were investigated. The differences between the TLLE and TLCM were found in different ratios from the period of fetal development to adulthood. Therefore, during medical treatment and surgical procedures this should be taken into account to avoid complications.  相似文献   
4.
Atalay E  Karaali K  Akar M  Ari ES  Simsek M  Atalay S  Zorlu G 《Maturitas》2005,50(4):282-288
Objective: To determine the effects of hormone replacement therapy (HRT) on ocular blood flow.

Study design: In a prospective controlled study, 40 healthy women who presented to the menopause clinic between December 2000 and December 2001 were randomly assigned into the study. The HRT-receiving group was administered estradiol 17-valerate 2 mg the first 11 days, and estradiol 17-valerate 2 mg plus ciproterone acetate 1 mg the next 10 days of the monthly cycle for 6 months. The control group did not receive any HRT for 6 months. The ocular colour Doppler analysis were performed at baseline and after 3 and 6 months. The ocular Doppler analysis was performed in the first half of the cycle in the HRT-receiving group.

Results: Central retinal artery and ophthalmic artery basal Doppler index (peak systolic velocity, end-diastolic velocity, resistive index and pulsatility index) values of the two groups at the beginning of the study did not show any statistically significant difference. Both the right and the left central retinal artery pulsatility index (PI) values of the study group, who received HRT at the end of the third and sixth months, showed a statistically significant decline (paired-samples test, P < 0.05), while the decrease in the resistive indexes was not significant.

Conclusion: These results suggest that 6 months of combined hormone replacement therapy with estradiol 17-valerate 2 mg plus ciproterone acetate 1 mg improves ocular vascular Doppler indices which may be a reflection of cerebral vascular status.  相似文献   

5.
Oxidative stress is an important pathophysiological mechanism in nonalcoholic steatohepatitis (NASH). To assess whether there are relationships between oxidative stress and antioxidant enzymes in the development of NASH, we investigated oxidative stress by measuring serum malondialdehyde (MDA) and nitric oxide (NO) and antioxidant status by measuring serum glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and superoxide dismutase (SOD). The study included 18 patients (13 men, 5 women; mean age 42 yr) with biopsy proven NASH and 16 healthy volunteers (10 men, 6 women; mean age 38 yr). Serum levels of MDA, NO, GSH, GSH-Px, GR and SOD were determined by spectrophotometric methods. Serum levels (mean +/- SD) of MDA (6.7 +/- 1.6 vs 2.8 +/- 1.7 nmol/ml, p 0.0001), NO (135 +/- 28 vs 113 +/- 35 mmol/L, p 0.04), GSH (919 +/- 137 vs 770 +/- 128 mmol/L, p 0.003) were increased in patients with NASH vs controls. Serum levels of GSH-Px (1063 +/- 152 vs 1000 +/- 94 U/L) and GR (47 +/- 22 vs 40 +/- 21 U/L) were not singnificantly different in the patients vs controls. However, the serum level of SOD (1.24 +/- 0.32 vs 1.51 +/- 0.37 U/ml, p: 0.04) was significantly decreased. Impaired antioxidant defense mechanisms may be an important factor in the pathogenesis of NASH. Treatment approaches that affect the antioxidant enzymes may be beneficial in patients with NASH.  相似文献   
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Purpose

To evaluate the efficiency of perforated punctal plug in acquired punctal stenosis.

Materials and methods

Forty-five eyes of 33 patients who had epiphora due to punctal stenosis were included in this study. After biomicroscopic examination and lacrimal dilatation punctal stenosis was managed with the perforated punctal plugs in all patients. In the following period epiphora, plug tolerance, lacrimal drainage were evaluated and graded. Lacrimal drainage was evaluated with fluorescein dye disappearing test.

Results

The age of the patients ranged between 31 and 80 (mean 55.78 ± 13.11). Preoperatively punctal dilatation and lacrimal system irrigations were performed on all patients. Lacrimal system irrigation was positive in all patients. Perforated punctal plugs were placed in the inferior puncti in all patients. The plugs were explanted 6 months after operation. The follow-up period ranged between 6 and 24 months. Plug tolerance was good in 97.8% of the eyes in the 1st month visit. Epiphora decreased remarkably in 88.9% of the patients 1 month after plug implantation, except one whose plug dropped off spontaneously in 2 weeks. Fluorescein disappearing times were found under 3 min in 97.8% of the eyes after plug explanations.

Conclusion

Punctum stenosis is one of the several disorders that cause lacrimal drainage obstruction. Perforated punctal plugs are found convenient and effective in managing punctal stenosis.  相似文献   
10.
Surgical treatment of axillary artery aneurysm   总被引:2,自引:0,他引:2  
Aneurysms of the axillary artery are rare and dangerous lesions that threaten the upper extremities with vascular and neurologic compromise. Most can be treated effectively with surgical excision and vascular grafting. We retrospectively assessed 4 axillary artery aneurysms upon which we operated from February 1998 through March 2004. Three patients were admitted to our clinic for symptomatic axillary masses. The remaining patient was transported to our clinic emergently due to massive hemorrhage of an enlarging axillary mass that occurred during biopsy of the mass at another hospital. In this patient, the ruptured axillary artery aneurysm was diagnosed by means of emergent upper-extremity selective angiography. All patients were treated surgically by means of aneurysmectomy and graft interpositioning--with polytetrafluoroethylene grafts in 2 patients and saphenous vein grafts in the other 2. Surgical treatment of axillary artery aneurysms is of importance in avoiding thromboembolism and ischemia, which in turn can lead to gangrene and amputation of the affected extremity. For this reason, operative management of such cases should not be delayed.  相似文献   
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