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101.
目的:探讨无张力疝修补术在治疗老年嵌顿性腹股沟斜疝中的应用。方法:回顾分析在我院进行无张力疝修补术治疗的63例老年嵌顿性腹股沟斜疝患者的临床资料。结果:本组全部完成手术,平均手术时间50分钟,手术效果满意,术后随访1.3~6年均未见复发。结论:无张力疝修补术可以安全、有效地应用于老年嵌顿性腹股沟斜疝的患者。  相似文献   
102.
聚丙烯单丝线植入式重睑术   总被引:1,自引:1,他引:0  
目的:介绍一种新型材料(聚丙烯单丝线)植入式重睑术。方法:按上睑长度设计重睑线,从内到外标记出6点,即A、B、C、D、E、F点。重睑宽度按6~8mm设计。用带针聚丙烯单丝线从A点穿入,B点穿出,再从B点穿入C点穿出,直至穿出F点。将A、F点余线轻提剪除,使线头埋入皮下。结果:施术208例,其中184例形态良好;16例术后1月也恢复良好:8例内、外眦部重睑线消失,需再次手术。结论:聚丙烯单丝线植入式重睑术方法简单,操作方便快速,损伤小,肿胀轻微,恢复快,受术者容易接受。  相似文献   
103.
获得高性能碳纳米管(MWCNT)增强聚合物复合材料的关键在于控制碳纳米管在聚合物基体中的分布与取向。传统的注塑成型工艺下,碳纳米管容易发生取向,其表面电阻率远远大于模压成型时的电阻率。本文通过调整注塑工艺改变剪切场实现对碳纳米管在基体中分布与取向的控制。结果表明:在低熔体温度和高注射速度下,碳纳米管局部取向,导电性能下降;而在高熔体温度和低注射速度下,碳纳米管分散良好,导电网络优良,聚丙烯/碳纳米管(PP/MWCNT)注塑制品的导电性能得到有效提升,其表面电阻率下降了约5个数量级。加入膨胀石墨(EG)有增强导电网络的作用,使PP/MWCNT/EG复合材料的导电网络更为完善,其导电性能进一步提高,尤其在低熔体温度和高注射速度下最为明显;随着EG含量的增加,PP/MWCNT/EG的表面电阻率下降了3个数量级。  相似文献   
104.
The molar mass distributions of high‐molar‐mass PE and PP were characterized using HT‐AF4 and HT‐SEC in combination with IR and MALS detection. Calculated molar mass distributions, average molar masses and radii of gyration were compared. It was found that HT‐AF4 can detect the real extent of thermo‐oxidative degradation during dissolution. HT‐SEC is affected by shear and thermo‐oxidative degradation while in HT‐AF4 no shear stress exists. As a consequence, the molar mass averages obtained from HT‐SEC are pronouncedly lower as obtained from HT‐AF4. In addition, branched polyolefins cannot be correctly characterized by SEC‐MALS due to abnormal co‐elution effects. HT‐AF4 is therefore the method of choice for studying the thermo‐oxidative degradation of macromolecules with high molar masses.

  相似文献   

105.

Background:

Cefazolin is a semisynthetic penicillin derivative with a narrow spectrum of activity covering some gram-positive organisms and a few gram-negative aerobic bacteria.

Objective:

To determine the physical and chemical stability of cefazolin sodium reconstituted with sterile water for injection and stored in polypropylene syringes or diluted with either 5% dextrose in water (D5W) or 0.9% sodium chloride (normal saline [NS]) and stored in polyvinylchloride (PVC) minibags.

Methods:

Reconstituted solutions of cefazolin (100 or 200 mg/mL) were packaged in polypropylene syringes. More dilute solutions (20 or 40 mg/mL) were prepared in D5W or NS and packaged in PVC minibags. For each concentration–diluent–container combination, 3 containers were designated for each day of analysis (days 7, 14, 21, and 30). Containers were stored under refrigeration (5°C) with protection from light until the designated day of analysis, at which time one 5-mL sample was collected from each the designated container. The designated containers were then stored at room temperature (21°C to 25°C) with exposure to light for an additional 72 h, and additional samples were drawn. The samples were assayed using a validated, stability-indicating high-performance liquid chromatography method. The colour and clarity of the solutions, as well as their pH, were also monitored on each sampling day.

Results:

All samples remained clear for the duration of the study; they had a slight yellow colour that darkened over time, and there was an increase in pH. Solutions diluted with sterile water for injection and stored in polypropylene syringes retained at least 94.5% of the initial concentration after 30 days of refrigerated storage and at least 92.1% after an additional 72 h at room temperature with exposure to light. Samples diluted in D5W or NS and stored in PVC minibags retained at least 95.8% of the initial concentration after 30 days of refrigerated storage and at least 91.8% after an additional 72 h at room temperature with exposure to light.

Conclusions:

Cefazolin at various concentrations stored in polypropylene syringes or PVC minibags was stable for up to 30 days with storage at 5°C with protection from light, followed by an additional 72 h at 21°C to 25°C with exposure to light.  相似文献   
106.
通过熔纺/冷拉伸法制备了微孔聚丙烯中空纤维膜。研究了工艺条件对微孔聚丙烯中空纤维膜的微孔结构与性能的影响。结果表明:随着纺丝温度的下降或熔体拉伸比的提高,最大可几孔径及孔隙率增大;熔纺中冷却风速提高,最大可几孔径及孔隙率较大;温度低于110℃时,热处理对最大可几孔径及孔隙率的影响较小,在120-130℃时,随着热处理温度的增加,最大孔径及孔隙率有明显增加的趋势;随着初纺中空纤维拉伸倍数的增加,孔隙率先增加而后下降。  相似文献   
107.
AIM: To evaluate the safety and efficacy of the SPARC sling in women with urinary incontinence. METHODS: Women who presented with urinary incontinence symptoms were included in this prospective study. In total, 103 women underwent evaluation of subjective and objective cure rates, quality of life and urodynamic parameters following the SPARC procedure. RESULTS: The objective cure rate, defined as a pad weight test less than 1 g and negative cough stress test, was 84.4% at 12 months. Subjective cure rates, defined as no usage of pads/no urine loss during daily activities, were also encouraging: 75.0% at 12 months. Quality of life evaluation included asking patients to rate the amount of bother caused by their incontinence symptoms on a scale from 0 to 100. Preoperatively, the average was 76.7, dropping to 15.9 at 12 months. At 6 months, 93.7% (75/79) were 'very satisfied' and 5.1% (4/79) were 'satisfied;' one patient was 'dissatisfied' (1.2%, 1/79). Seventy-eight of 79 patients (98.7%) would recommend the procedure to a friend and undergo the procedure again. Patients returned to inside work an average of 1.4 days and to outside work 5.4 days after the procedure. The maximum flow rate decreased from a mean of 43.4 mL/s preoperatively to 37.08 mL/s at 12 months postoperatively (P = 0.049). Detrusor pressure at maximum flow and maximal urethral closure at rest increased from 16.94 and 50.85 cmH(2)O preoperatively to 21.69 and 60.61 cmH(2)O at 12 months, respectively (P = 0.015; P < 0.001). There were few postoperative complications, with no reported infections, erosions or hematomas. CONCLUSIONS: This prospective study demonstrates that the SPARC suprapubic sling is a safe and effective treatment for female stress urinary incontinence. Both objective and subjective measures of success were achieved, with low complication rates. Quality of life and urodynamic parameters were improved. The SPARC method provides safe and highly effective treatment for female stress urinary incontinence at one year.  相似文献   
108.
Rehabilitation and reanimation of the paralyzed face remains a challenge. A variety of autografts and allografts have been used for static facial suspension. We report two cases of long-standing partial facial paralysis treated with 3C triple-convergence polypropylene thread. A 39-year-old woman with right-sided partial facial paralysis underwent an endoscopy-assisted facial suspension using the 3C threads and a 60-year-old woman with right-sided partial facial paralysis underwent a round face-lifting combined with endoscopic brow lift and placement of 3C triple-convergence polypropylene threads. Its use for partial facial paralysis has not been previously described. The 1-year follow-up shows effective preservation of the surgical result and patient satisfaction.  相似文献   
109.
To retrospectively analyze the outcome of surgery in women followed up for 1 year after vaginal repair with the Apogee® (support of posterior vaginal wall) or Perigee® (support of anterior vaginal wall) system. A total of 120 patients with recurrent cystocele and/or rectocele or with combined vaginal vault prolapse were treated by either posterior or anterior mesh interposition depending on the defect. Follow-up after 1 year (±31 days) comprised a vaginal examination with prolapse grading using the POP-Q system, measurement of vaginal length, evaluation of the vaginal mucosa, and exploration for mesh erosions. Postoperatively, 112 (93%) women were free of vaginal prolapse, whereas 8 (7%) had level 2 defects. Erosions occurred significantly more often (p?=?0.042) in patients treated with the Perigee system. Our results suggest that the Apogee® and Perigee® repair systems (monofilament polypropylene mesh) yield excellent short-term results after 1 year.  相似文献   
110.
BACKGROUND: The use of intra-peritoneal polypropylene mesh (PPM) to repair incisional hernia carries the risk of adhesions and damage to the intra-abdominal viscera. Polyglactin 910 mesh (PGM) is advocated to avoid contact between PPM and the intra-abdominal viscera. An experimental study in rats was performed to determine if interposition of a resorbable prosthesis between the PPM and viscera alters biocompatibility, adhesion formation, and herniation. MATERIALS AND METHODS: A 2- x 3-cm abdominal wall defect was created in 80 rats. Rats were randomly assigned for repair with 2.5- x 3.5-cm PPM (n = 40) or 2.5- x 3.5-cm PPM plus polyglactin 910 mesh (PPM-PGM) (n = 40). The rats were sacrificed at 1, 2, 3, and 6 months (n = 10), and an autopsy was performed to determine herniation and adhesion rates. Mesh-fascia interface was taken for histology. RESULTS: In the PPM group, 1 rat died before the end of the experiment, and at 6 months one of the 10 rats had a herniation. In the PPM-PGM group, two rats died before the end of the experiment, and two rats had a herniation after 1 month and three rats after 6 months. At 1, 2, and 3 months the adhesion score in the PPM group (median, 3; range, 2-3) did not differ from the score in the PPM-PGM group (median, 3; range, 2-3). Also, at 6 months the adhesion score in the PPM group (median, 2; range, 2-3) did not differ from the score in the PPM-PGM group (median, 3; range, 2-3). At microscopy a capsule was formed around the PP fibers, which matured over months in the PPM group. In the first month after implantation an inflammatory response was seen. Histology was similar in both groups, although in the early PPM-PGM group the inflammatory response was more evident. CONCLUSION: Interposition of PGM between PPM and viscera does not alter adhesion formation nor influences herniation rate.  相似文献   
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