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101.
102.
PURPOSE: To evaluate early and late period results of the implantation of single-piece foldable acrylic intraocular lens (IOL) in the sulcus in eyes developing a posterior capsule tear (PCT) during phacoemulsification (PE). SETTING: S.S.K. Vakif Gureba Training Hospital Eye Clinic, Istanbul, Turkey. METHODS: This prospective and noncomparative study consisted of 89 eyes of 88 patients in which PCT developed, with or without vitreous loss, and that were followed up for at least 1 year. The IOL was implanted in the sulcus in all eyes with sufficient capsule support. Postoperative best corrected visual acuity (BCVA), anterior segment biomicroscopy, intraocular pressure (IOP), IOL centralization, and fundus were analyzed. RESULTS: Temporary corneal edema, the most frequently observed cause of reduced vision in the early period, appeared in 33 eyes; high IOP in 17 eyes; anterior chamber inflammatory reaction in 5 eyes; clinical cystoid macular edema in 7 eyes; and retinal detachment in 1 eye. The IOL was decentered in 4 eyes and dislocated in 1 eye. Repositioning was performed in 2 eyes. No IOL was removed. In the early period, BCVA was 5/10 and above in 41 eyes; the final BCVA was 4/10 and below in 16 eyes and of 5/10 and above in 73 eyes. CONCLUSIONS: The implantation of foldable acrylic IOL in the sulcus in eyes developing posterior capsule tear during phacoemulsification surgery maintains the advantages of a small incision. Postoperative visual results were good, complications were few, and IOLs were centered.  相似文献   
103.
The purpose of this study was to investigate the biomechanical and histological features of patellar tendon-bone autografting and free flexor-tendon autografting, which were fixed by two different techniques at the tendon-bone junction in reconstruction of an infraspinatus defect in sheep. Merino type sheep ( n=10) were divided into two groups. Following a defect in the infraspinatus tendon, in group I (flexor-tendon autografting) the free end of the flexor tendon was passed through the holes in the greater tuberosity for fixation. In group II (patellar tendon-bone autografting), fixation was obtained by impaction of the tibial bone plug to the greater tuberosity. Twelve weeks later, animals were sacrificed and specimens were evaluated biomechanically and histologically. Recovery of tensile mechanical properties was achieved to a level of approximately 50% in Group I and 70% in Group II at the end of the 12th week. No difference in the stiffness values was found. In group I, there was a difference between operated and contralateral (non-operated) tendons for the ultimate tensile strength values, but no difference was found in group II. Histologically, in group I, the defective area, which filled with a hypercellular connective tissue, could hardly be differentiated from the normal tendon tissue. In group II, complete incorporation of the bone block was seen in all specimens. These results suggested that patellar tendon-bone autografting is more advantageous than free flexor-tendon autografting in infraspinatus defect, providing rapid healing and better mechanical properties, especially in the early period of healing.  相似文献   
104.
INTRODUCTION: It is considered that many factors may play a role in urolithiasis. Experimental and clinical studies have shown that zinc has an inhibitory effect on urolithiasis. MATERIALS AND METHODS: In this study, urinary zinc and copper were measured in 27 healthy controls and 30 calcium oxalate stone formers. RESULTS: Urinary zinc excretion was significantly higher (p < 0.001) in stone formers than healthy controls (2,575 +/- 274 and 960 +/- 80 mg/day, respectively). There was no significant difference in urinary copper excretion between healthy controls and stone formers (32.3 +/- 3.5 and 33.3 +/- 3.2 microg/day, respectively). CONCLUSIONS: According to our results, the potent inhibitory effect of urinary zinc excretion on urolithiasis could be reviewed.  相似文献   
105.
Wilms' tumor in adults is rare, and no treatment guidelines have been established. Spinal cord compression has also been rarely reported in all age groups. In this case report, we present a 19-year-old adolescent with recurrent Wilms' tumor, a paraspinal dumbbell mass, metastatic involvement of the vertebral bodies, lung metastasis, and pregnancy. To our knowledge, this is the first report of a pregnant patient with Wilms' tumor who had to undergo immediate chemotherapy with vincristine and actinomycin-D owing to spinal cord compression at 25 weeks of pregnancy. After delivery, complete remission was maintained with a regimen of ifosfamide, carboplatin, and etoposide and vincristine, actinomycin-D, and cyclophosphamide. No teratogenic or other toxic effects of vincristine or actinomycin-D were observed in the fetus.  相似文献   
106.
Hemodynamic changes during gaseous and gasless laparoscopic cholecystectomy   总被引:3,自引:0,他引:3  
Abstract. Purpose: The main disadvantage of gaseous laparoscopic surgery is the need for CO2 insufflation and the elevation of intra-abdominal pressure. Gasless laparoscopic surgery is an alternative to gaseous laparoscopic surgery, which avoids the hazardous effects of pneumoperitoneum. This study was conducted to investigate the hemodynamic effects of pneumoperitoneum and to compare gasless and gaseous laparoscopic cholecystectomy on a hemodynamic basis. Methods: The gasless laparoscopic procedure uses an electromechanical retractor system to lift the abdominal wall. We performed 20 gaseous and 11 gasless laparoscopic cholecystectomies in a collective total of 31 patients with symptomatic gallostones. The mean arterial pressure, heart rate, end diastolic index, systemic vascular resistance index, cardiac index (CI), ejection fraction (EF), and stroke index (SI) values were monitored noninvasively by thoracic electrical bioimpedance. Results: In the gaseous group, statistically significant changes were detected in CI, EF, and SI values after insufflation as compared to the values before pneumoperitoneum. In the gasless group, only minimal changes were detected in the SI values, which were not significant. Conclusion: Gasless laparoscopy has little effect on the hemodynamic parameters of patients and provides an alternative to the gaseous technique in selected cases. Received: December 6, 2000 / Accepted: January 8, 2002  相似文献   
107.
BACKGROUND: In general, laparoscopic surgery is more expensive than open surgery. However, recent reports showed lower overall cost. PATIENT AND METHODS: Fourteen patients underwent laparoscopic splenectomy (LS) and 15 patients open splenectomy (OS). Patients were evaluated with regard to blood loss, complication rate, length of hospital stay, operative time, presence of accessory spleens, hospital cost, and total cost. For the OS group, there was no laparoscopic instrument cost, and the total cost was equal to the hospital cost. In the LS group, total cost was calculated by adding the hospital cost to the cost of laparoscopic instruments. RESULTS: The postoperative hospitalization was shorter in the LS group than the OS group (3.4 vs. 7.5 days), but the operating time was significantly longer for the LS group. The mean hospital cost was calculated as US $1,055 in the LS group and $1,664 in the OS group. The overall total cost was $1,664 for the OS group and $2,064 for the LS group. In the LS group, less morbidity and shorter postoperative hospital stay resulted in lower hospital cost. CONCLUSION: The cost for laparoscopic instruments is the main factor responsible for the high total cost of LS. Resterilization of disposable laparoscopic instruments is feasible and a more economic way of treatment compared with splenectomy with totally disposable laparoscopic instruments and has costs comparable to those of open surgery.  相似文献   
108.
Primary nocturnal enuresis (PNE) is the most common type of nocturnal enuresis in children, but its etiology remains unclear. Recent studies indicated the differences in urinary electrolytes in enuretic children, and stressed the existence of a renal tubular maturation defect. In this study, 30 children (aged 6-12 years) with PNE were investigated in comparison with 18 healthy controls. We evaluated plasma antidiuretic hormone, electrolytes, 24-h urine volume, osmolarity, and urinary electrolytes. Unlike other studies, we firstly assessed the plasma and urinary adrenomedullin (AM) and total nitrite levels, a stable product of nitric oxide (NO), and investigated their relationship with urinary electrolytes. The plasma AM and total nitrite levels were significantly lower than controls. Urine volume (24-h) and potassium excretion were higher than in controls. However, 24-h urinary osmolarity and excretion of AM were significantly lower than in controls. Our results indicate that there may be a problem in renal regulation of potassium in children with PNE. Although decreased levels of AM and total nitrite may be a compensatory response to abnormal potassium and water excretion, further investigations are required to exclude whether the renal synthesis of AM and NO are also deficient in these children.  相似文献   
109.
110.
The rates of survival of the amputated part and the functional outcomes were studied retrospectively after 13 replantations and 12 revascularizations in 25 children. The ages of the patients ranged from 2 to 15 years (mean, 6.4 years). The average duration of follow-up was 4.2 years (range, 2 to 7 years). The survival rate was higher after revascularization (94.6%) than after replantation (84.6%). Sensory recovery of all digits was satisfactory. The mean growth rate of replanted digits relative to contralateral digits was 80%. Functional results were rated as excellent in 11 cases, good in 8 cases, moderate in 2 cases, and poor in 1 case. In order to prevent functional and growth disturbances and due to cosmetic reasons, replantation or revascularization should definitely be tried for children. © 1998 Wiley-Liss, Inc. MICROSURGERY 18:410–413, 1998  相似文献   
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