首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   927篇
  免费   57篇
  国内免费   3篇
耳鼻咽喉   13篇
儿科学   46篇
妇产科学   59篇
基础医学   82篇
口腔科学   113篇
临床医学   82篇
内科学   184篇
皮肤病学   17篇
神经病学   113篇
特种医学   29篇
外科学   109篇
综合类   5篇
预防医学   36篇
眼科学   34篇
药学   38篇
中国医学   1篇
肿瘤学   26篇
  2024年   1篇
  2023年   15篇
  2022年   26篇
  2021年   61篇
  2020年   39篇
  2019年   42篇
  2018年   52篇
  2017年   44篇
  2016年   52篇
  2015年   49篇
  2014年   65篇
  2013年   68篇
  2012年   108篇
  2011年   75篇
  2010年   26篇
  2009年   35篇
  2008年   49篇
  2007年   38篇
  2006年   54篇
  2005年   35篇
  2004年   24篇
  2003年   13篇
  2002年   11篇
  2001年   2篇
  2000年   2篇
  1999年   1篇
排序方式: 共有987条查询结果,搜索用时 15 毫秒
41.
Cyclosporine A (CsA), broadly used in organ transplantation, may contribute to pathogenesis of osteoporosis. The aim of this study was to investigate the effects of CsA on alveolar bone in rats subjected or not to experimental periodontal disease using biochemical, radiographic, and histometric analysis. Forty Wistar rats were divided into 4 equal groups: Group I (Control), Group II (CsA was injected subcutaneously in a daily dose of 10 mg/kg), Group III (Ligature was placed around the mandibular molars), Group IV (Ligature+CsA). After 60 days, rats were decapitated, serum alkaline phosphatase and calcium levels were measured. Radiographic-alveolar bone loss (ABL), histometric-ABL, and percentage of new alveolar bone formation (NABF%) were determined on mandibular molars. Significant increase in serum alkaline phosphatase levels (p < 0.001), no significant difference in calcium levels were observed (p > 0.05) in Group IV compared to Group III. Radiographic and histometric-ABL were significantly less (p < 0.001), NABF% was significantly greater (p < 0.05) in Group IV than in Group III. No significant difference in any of the parameters between Group II and Group I was found. It can be concluded that in the presence of periodontal disease, CsA treatment may bring out an imbalance in the alveolar bone homeostasis by decreasing resorption and stimulating formation of alveolar bone in rats.  相似文献   
42.

Purpose

The purpose of our study is to evaluate results of percutaneous aspiration with alcohol sclerotherapy in symptomatic patients with simple hepatic cysts by employing single-session techniques either by a needle or a catheter.

Materials and Methods

We retrospectively included 39 simple hepatic cysts in 35 patients treated via percutaneous aspiration and single-session alcohol sclerotherapy between years 1993 and 2012. Indications were pain (n = 28) or ruling out cystic echinococcus (CE) disease (n = 7). 29 cysts in 26 patients were treated by needle technique (Group A) and ten cysts in nine patients were treated by single-session catheter technique (Group B). Patients were followed for 4–173 months (median: 38 months).

Results

All patients were successfully treated. Before procedure, cyst volumes were 21–676 cc (median: 94 cc). Post-procedure cyst volumes at last follow-up were 0-40 cc (median: 1 cc). The mean decrease in cyst volume was 95.92 ± 2.86 % in all patients (95.96 ± 3.26 % in Group A and 95.80 ± 6.20 % in Group B). There was no statistically significant difference between the volume reduction rates of Group A and Group B. Only one patient, in Group B, developed a major complication, an abscess. Hospitalization period was 1 day for all patients.

Conclusions

For patients with symptomatic simple hepatic cysts smaller than 500 cc in volume by using puncture, aspiration, injection, and reaspiration (PAIR) technique with only needle, single-session alcohol sclerotherapy of 10 min is a safe and effective procedure with high success rate.
  相似文献   
43.
Background: YKL‐40, a new acute‐phase protein, is shown to be elevated in inflammatory diseases, such as rheumatoid arthritis, type 2 diabetes mellitus, and coronary artery diseases. However, there is no data indicating a relationship between YKL‐40 and periodontal disease. Interleukin‐6 (IL‐6) is the major regulator of acute‐phase protein synthesis and one of the most studied inflammatory markers in periodontal disease. The purpose of the present study is to evaluate YKL‐40 and IL‐6 levels in gingival crevicular fluid (GCF) and serum of patients with periodontal disease and healthy individuals. Methods: Periodontally healthy individuals (n = 15), patients with gingivitis (n = 15), and patients with severe chronic periodontitis (CP) (n = 15) without any systemic disease were included in the study. Clinical measurements were recorded; GCF and blood samples were obtained from each participant. GCF and serum YKL‐40 and IL‐6 levels were analyzed by enzyme‐linked immunosorbent assay. Statistical analysis was performed by parametric and non‐parametric tests. Results: Total amounts of YKL‐40 and IL‐6 in GCF as well as serum YKL‐40 and IL‐6 levels were significantly higher in patients with gingivitis and CP compared with healthy controls (P <0.01). YKL‐40 levels in GCF and serum as well as serum IL‐6 levels were significantly higher in patients with CP compared with patients with gingivitis (P <0.01). Conclusions: YKL‐40 levels in GCF as well as serum YKL‐40 and IL‐6 levels increased from gingivitis to periodontitis. Within the limits of the present study, the YKL‐40 molecule might be a potential novel inflammatory marker of periodontal disease.  相似文献   
44.
Background: Australia has the highest incidence of cutaneous squamous cell carcinoma in the world. The majority of lesions occur in the head and neck with metastases to the parotid gland lymph nodes reflecting an uncommon, but aggressive, manifestation. Parotidectomy ± neck dissection followed by adjuvant radiotherapy should be considered as best practice. Methods: Between 1983 and 2000, seventy-four patients were treated for metastatic cutaneous squamous cell carcinoma to the parotid with surgery and adjuvant radiotherapy at Westmead Hospital, Sydney. Relevant data were extracted from patient files and a prospectively maintained database. Patterns of relapse and outcome were analysed. Results: Median age at diagnosis was 65 years (34−93 years) in 63 men and 11 women. Median follow-up duration was 41 months (12−188 months). All patients underwent parotidectomy with 52 undergoing a simultaneous neck dissection. Twelve patients required sacrifice of the facial nerve (4) or one or more branches (8). All received adjuvant radiotherapy to the parotid region with 56 also receiving radiotherapy to the ipsilateral neck. Despite treatment, 24% developed locoregional recurrence, with a median time to relapse of 7.5 months. The most common site for recurrence was the treated parotid region and upper neck. Most relapsed patients died. No variable independently predicted for locoregional recurrence on multivariate analysis. The 5-year absolute and cause-specific survival rates were 58% and 72%, respectively. Conclusion: Parotid gland lymph node metastases from cutaneous squamous cell carcinoma are associated with a high rate of recurrence and cause-specific mortality despite current best practice (surgery and high dose adjuvant radiotherapy). The role of more aggressive surgery, altered fractionation or chemotherapy to enhance locoregional control remains unclear.  相似文献   
45.
A 46-year-old man with liver lesions referred to us as having “metastases of a malignant mesenchymal tumor” underwent PET/computerized tomography (CT) imaging for the localization of the primary tumor and determination of the extent of disease. No pathological FDG uptake was observed in PET/CT images obtained after 60 min, following FDG injection but delayed PET/CT images demonstrated intense FDG uptake at the liver masses. Since the PET/CT findings were discordant with the initial diagnosis, the pathology specimen was reevaluated and with certain immunohistochemical examinations, the final histopathological decision was changed to epithelioid hemangioendothelioma (EHE). In this report, we discuss the FDG uptake pattern in a patient with hepatic EHE and emphasize the importance of dual-time-point hepatic FDG-PET/CT imaging.  相似文献   
46.

Background Context

Epidural steroid injection is commonly used in patients with chronic low back pain. Applying a mixture of a local anesthetic (LA) and steroid using the interlaminar (IL), transforaminal, and caudal techniques is a preferred approach.

Purpose

The present study aims to investigate the efficacy of interlaminar epidural steroid administration in patients with multilevel lumbar disc pathology (LDP) and to assess the possible correlation of the procedure's success with age and body mass index (BMI).

Study Design

A randomized controlled trial was performed.

Patient Sample

We administered interlaminar epidural steroid to a total of 98 patients with multilevel LDP.

Outcome Measures

The visual analog scale (VAS) and Oswestry Disability Index (ODI) scoring were performed on the study population at pretreatment (PRT), posttreatment, and 1, 3, 6, and 12 PRT months. A possible correlation of BMI and age with the procedure success was evaluated.

Methods

The LA group (Group L, n=50) received 10?mL 0.25% bupivacaine, whereas the steroid+LA group (Group S, n=48) received 10?mL 0.25% bupivacaine+40?mg methylprednisolone at L4–L5 intervertebral space in prone position under the guidance of C-arm fluoroscopy.

Results

There was no statistical difference in the PRT VAS and ODI scores between the groups (p<.05), whereas the VAS and ODI scores at 1, 3, 6, and 12 posttreatment months were higher in Group L, compared with Group S (p<.05). Age and BMI were not found to be related with the success of the procedure.

Conclusions

Our study results showed that the VAS and ODI scores were lower in patients with multilevel LDP receiving steroid, following the administration of IL epidural injection. However, further studies are required to establish a robust conclusion on the dispersion of IL epidural injections in the epidural area and the dose of steroid.  相似文献   
47.
Aim. Reports on the clinical presentation of adult‐onset neuronal ceroid lipofuscinoses (NCL) are scarce compared to infantile‐ and childhood‐onset forms. Here, we aimed to present detailed temporal evolution of clinical and electrophysiological features of two siblings with adult‐onset NCL and homozygous mutation in the CLN6 gene. Methods. We retrospectively analysed medical records and electrophysiological data in order to delineate evolution of clinical and electrophysiological findings. Electrophysiological studies included routine EEG and video‐EEG, as well as polymyographic analysis of myoclonus and brainstem reflex studies. Results. Both patients had seizures and cerebellar signs. Despite the slow progression of ataxia, they developed no mental deterioration, but had severe obsessive compulsive disorder and depression. EEG revealed frequent generalized spikes, polyspikes, and waves, prominent on awakening and during photic stimulation without significant change throughout the clinical course. Abnormalities concerning the blink reflex, auditory startle response, and startle response to somatosensory inputs manifested within four years. The patients underwent transient and mild improvement with valproate, whereas ataxia and seizures were dramatically ameliorated following high‐dose piracetam. Conclusions. Patients with adult‐onset NCL may present with slowly progressive ataxia, persistent photosensitivity, and seizures without dementia or extrapyramidal findings. Brainstem abnormalities become more evident with time, in line with ataxia. Piracetam is effective for both seizures and ataxia.  相似文献   
48.
Langerhans cell histiocytosis is a collective term used to describe a group of enigmatic proliferative disorders. Three disease variants include eosinophilic granuloma, Letterer-Siwe disease, and Hand-Schuller-Christian syndrome. Eosinophilic granuloma is reported to be the most benign type of the triad. In this report, a 7-year-old child with an eosinophilic granuloma of the left side of her mandible is presented. There was a painless, hard, tender mass arising from the left side of the molar region. Panoramic radiographs showed a radiolucent area at the molar region. The lesion was resolved 2 weeks after the biopsy. The 1.5 years of radiographic and clinical follow-up was satisfactory.  相似文献   
49.
Inflammatory bowel disease, a chronic condition of the intestine, is associated with numerous extraintestinal manifestations, including pancreatitis. This study investigated the effect of octreotide administration on oxidative damage in a rat model of colitis induced by 2,4,6-trini-trobenzene sulfonic (TNBS) acid. Colonic and pancreatic malondialdehyde and glutathione levels are indicators of oxidative damage, and TNBS-induced colitis significantly increased the colonic and pancreatic malondialdehyde levels and decreased glutathione levels. Octreotide treatment was associated with decreased malondialdehyde levels and increased glutathione levels in the colonic and pancreatic tissue. The colonic mucosal structure was preserved and pancreatic inflammation decreased in rats treated with octreotide. Octreotide also significantly decreased nuclear factor-kB expression by immunohisto-chemistry in the colonic and pancreatic tissue compared with TNBS-induced colitis group. Octreotide appears to have protective effects against TNBS-induced colonic and pancreatic damage. These results imply the reduction in mucosal damage owing to the anti-inflammatory and antioxidant effects of octreotide.  相似文献   
50.
The aim of the study was to investigate the efficiency of ram seminal plasma and fetal calf serum on freezing of buck semen. Twenty ejaculates were collected using an electro-ejaculator and split into six groups. While FCS additive was not used in A1, A2 and A3 groups, 10% FCS was added to B1, B2 and B3 groups. These groups were then edited according to whether the buck or ram SP was involved. The design of the groups was done as follows: Group A1 (control 1), group A2 without buck SP, group A3 containing ram SP instead of buck SP. Groups B1 (control 2), B2 and B3 were the FCS added forms of these groups. Progressive sperm motility percentages in Group A1 and Group B2 were found to be higher when compared to the lowest Group B3. There were no significant differences between the groups in neither the levels of reactive oxygen species nor the enzyme and glutathione activities. In conclusion, the lack of statistical difference between the groups suggested that despite the supplements used but only when the buck spermatozoa structure was healthy, the cell could preserve acrosome, DNA and the integrity of membrane.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号