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21.
BACKGROUND AND OBJECTIVES: Improved laser treatment of cutaneous hypervascular lesions is expected by utilizing higher incident dosages, longer pulse durations and longer wavelengths than those currently used in clinical settings. However, simply increasing the incident dosage will also increase the risk of nonspecific thermal injury to the epidermis due to light absorption by melanin. In this study, we investigated the thermal response of human skin epidermis to 595-nm wavelength laser irradiation at high incident dosages (up to 20 J/cm(2)) and long pulse durations (up to 40 milliseconds) in conjunction with cryogen spray cooling (CSC) using ex-vivo human skin samples. STUDY DESIGN/MATERIALS AND METHODS: The Candela V-beam trade mark laser (595-nm wavelength) was used in the experiments. Ex-vivo human skin samples (Fitzpatrick types I-VI) were irradiated at the incident dosages D(0) = 4, 6, 10, 15, and 20 J/cm(2), laser pulse durations tau(laser) = 1.5, 10, and 40 milliseconds, without and with CSC (refrigerant-134A, spurt duration tau(CSC) = 100 milliseconds). Thermal injury to the epidermis was evaluated by histological observations. RESULTS: Under the same incident dosage, longer pulse durations led to reduced thermal injury to the epidermis. Without CSC, no demonstrable thermal injury to the epidermis was observed in skin types I-II irradiated at the incident dosage as high as 15 J/cm(2), and in skin types III-IV at 10 J/cm(2). When CSC was applied, no evidence of thermal injury to the epidermis was present in skin types I-II even when irradiated at the maximum available incident dosage of the laser system (20 J/cm(2)). In skin types III-IV, no demonstrable thermal injury to the epidermis was observed when using incident dosage as high as 15 J/cm(2) in conjunction with CSC. In skin type VI, thermal injury to the epidermis could not be avoided even at the setting D(0) = 4 J/cm(2), tau(laser) = 40 milliseconds in conjunction with CSC. CONCLUSIONS: For a given incident dosage, longer pulse durations help reduce thermal injury to the epidermis. When a 100-millisecond cryogen spurt is applied, thermal injury to the epidermis can be prevented in ex-vivo skin types I-IV when irradiated at higher incident dosages (15-20 J/cm(2)) than those currently used in clinical settings. Further studies on optimizing the CSC parameters in conjunction with the laser irradiation parameters are needed to protect skin types V-VI from thermal injury to the epidermis.  相似文献   
22.
Anvari M  Allen C 《Surgical endoscopy》2003,17(7):1029-1035
Laparoscopic fundoplication (LF) has been shown to be effective in treatment of patients with gastro-esophageal reflux disease (GERD) requiring long-term medical therapy. Its effectiveness in patients with poor response to proton pump inhibitors (PPIs) has been questioned. We prospectively followed 445 patients with proven GERD inadequately controlled on PPI (up to 120 mg/day) and 274 GERD patients with good response to PPIs (20–120 mg/day) after LF. Patients in both groups underwent 24 h pH testing, esophageal manometry, symptom score evaluation, and quality-of-life (QOL) assessment (SF-36) before and at 6 months, 2 years, and 5 years after surgery. LF was associated with a marked improvement in percentage acid reflux, lower esophageal sphincter pressure, and symptom control in both groups of patients; however, the poor responders to PPIs also had a significant improvement in both physical and mental health component of the QOL assessment. Laparoscopic fundoplication provides an excellent symptom control for GERD patients, even those who have responded inadequately to large doses of PPIs. GERD patients who respond poorly to PPI therapy have significantly lowered physical and mental health QOL scores. Laparoscopic fundoplication in this group of patients leads to marked improvement of both components of QOL by 2 years after surgery.  相似文献   
23.
Anvari M  Allen C 《Journal of the American College of Surgeons》2003,196(1):51-7; discussion 57-8; author reply 58-9
BACKGROUND: We conducted an objective followup of 181 patients after laparoscopic Nissen fundoplication during a 5-year period after surgery. STUDY DESIGN: Patients underwent 24-hour pH recording, esophageal manometry, and symptom score assessment for six gastroesophageal reflux disease symptoms preoperatively and at 6 months, 2 years, and 5 years after surgery. RESULTS: Laparoscopic fundoplication was associated with a significant (p < 0.0001) increase in lower esophageal sphincter pressure and a significant (p < 0.0001) drop in duration of acid reflux in 24 hours, and symptom score, 6, 24, and 60 months after surgery when compared with preoperative values. Twenty-one patients (12%) have experienced recurrence of reflux-type symptoms, but only six have required repeat surgery. Lower esophageal sphincter tone dropped between 6 months and 5 years after surgery, but was still an effective antireflux barrier. Patient satisfaction with surgery dropped over the 5-year followup but remained high, at 86%, after 5 years. CONCLUSIONS: Laparoscopic Nissen fundoplication remains an effective antireflux procedure at 5 years.  相似文献   
24.
目的:观察I型杜安眼球后退综合征患者的第8染色体。方法:连续观测了29例I型杜安眼球后退综合征患者的第8染色体。采用质粒DNA提取试剂盒方法从患者的外周血白细胞里分离提取DNA,选取D8S553和D8S1797做标记,用PCR法进行测定。结果:实验的所有病人样本中没有D8S553和D8S1797标记阳性。结论:我们的发现提示所观察的I型杜安眼球后退综合征患者的可能病因是属散发病例而没有家族史,建议纳入更多病例、选取其他的标记和不同的染色体进行进一步的研究。  相似文献   
25.
Since the application of minimally invasive techniques to antireflux surgery eight years ago, there has been a rapid increase in the use of laparoscopic antireflux surgery. It is increasingly used as an alternative to long term medical therapy with proton pump inhibitors. The factors responsible for the rapid popularity of this procedure are reviewed, and the choice of techniques, current indications and available literature on the outcomes of these procedures are discussed.  相似文献   
26.
27.

Purpose

Older age (>?60) has been considered a relative contraindication for bariatric surgery due to increased complication risk. This study examined the risks and benefits of bariatric surgery for patients older than 60 years in Canadian population.

Methods

This was a retrospective cohort study of the Ontario Bariatric Registry: a database recording peri-operative and post-operative outcomes of publicly funded bariatric surgeries across the province. Patients who completed 1 year follow-up, who underwent laparoscopic gastric bypass (LRYGB) or laparoscopic sleeve gastrectomy (LSG) between January 2010 and May 2013, were divided into older (>?60) and younger (>?60) cohorts, and outcomes were compared.

Results

Between January 2010 and May 2013, 3166 registry patients underwent LRYGB or LSG and completed 1-year follow-up. Of these, 204 (6.5%) were older than 60 years, with 175 (85.8%) undergoing LRYGB and 29 (14.2%) LSG. Demographics were similar, except for a higher number of males in the older group (59 (28.9%) versus 452 (15.3%) (p?<?0.001)). No significant difference in complication rate was noted (15% for younger cohort versus 13.8% (p?=?0.889)). The average percentage of excess weight loss was significantly higher in the younger population (60.72% versus 56.25% (p?<?0.05)) overall, however not significantly in the LSG group. Reduction in medication use post-surgery for management of co-morbidities was significantly higher in the older patients (??0.91 versus ??2.03 (p?<?0.001)).

Conclusion

The older cohort who underwent LRYGB or LSG was at no greater risk for intra-operative and post-operative complications and showed greater reduction in medication use post-surgery when compared to the younger cohort.
  相似文献   
28.
Bacterial endospores are some of the most resilient forms of life known to us, with their persistent survival capability resulting from a complex and effective structural organization. The outer membrane of endospores is surrounded by the densely packed endospore coat and exosporium, containing amyloid or amyloid-like proteins. In fact, it is the impenetrable composition of the endospore coat and the exosporium that makes staining methodologies for endospore detection complex and challenging. Therefore, a plausible strategy for facile and expedient staining would be to target components of the protective surface layers of the endospores. Instead of targeting endogenous markers encapsulated in the spores, here we demonstrated staining of these dormant life entities that targets the amyloid domains, i.e., the very surface components that make the coats of these species impenetrable. Using an amyloid staining dye, thioflavin T (ThT), we examined this strategy. A short incubation of bacillus endospore suspensions with ThT, under ambient conditions, resulted in (i) an enhancement of the fluorescence of ThT and (ii) the accumulation of ThT in the endospores, affording fluorescence images with excellent contrast ratios. Fluorescence images revealed that ThT tends to accumulate in the surface regions of the endospores. The observed fluorescence enhancement and dye accumulation, coupled with the sensitivity of emission techniques, provide an effective and rapid means of staining endospores without the inconvenience of pre- or posttreatment of samples.  相似文献   
29.
Introduction  Laparoscopic approach for colorectal resections is gaining popularity. Internal small bowel herniation (SBH) through a mesenteric defect has been described and, although rare, is a severe complication. The aim of this study was to evaluate the incidence and outcome of internal hernias after laparoscopic colorectal resection. Material and methods  During a 5-year period, all patients who underwent laparoscopic left colon resection were included in the study. A retrospective data base query was performed searching for all patients in whom SBH required surgical reintervention. Results  A total of 436 laparoscopic left colorectal resections were performed from January 2000 to July 2006. Five male patients presented symptomatic internal hernias and required re-operation. Four had a resection for cancer and one for sigmoiditis. The mesenteric defect was not initially closed in three cases. In all cases, we found small bowel hernias through the mesocolon defect. One patient was re-operated on post-op day 2 for mesenteric ischemia and died after 24 h. Discussion  Internal hernia is a rare but fatal complication after laparoscopic colonic resection. Suspicion of this diagnosis requires emergency re-operation because symptoms are nonspecific. Conclusion  All mesenteric defects created during colorectal laparoscopy surgery should be meticulously closed. SAGES April 2007, Las Vegas  相似文献   
30.
Ameloblastic fibrosarcoma (AFS) or ameloblastic sarcoma is an extremely rare odontogenic neoplasm. The authors report AFS in the maxillary sinus of a 4-month-old boy. The tumor was composed of odontogenic epithelium, resembling that of ameloblastoma, and a mesenchymal part exhibiting features of fibrosarcoma. We also found some areas with deposition of dentinoid material closely adjacent to the ameloblastic epithelium. Although AFS has occurred in a wide age range, this is the first report of this tumor in infancy with long-term follow-up.  相似文献   
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