全文获取类型
收费全文 | 2296篇 |
免费 | 70篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 81篇 |
儿科学 | 138篇 |
妇产科学 | 108篇 |
基础医学 | 154篇 |
口腔科学 | 108篇 |
临床医学 | 177篇 |
内科学 | 522篇 |
皮肤病学 | 79篇 |
神经病学 | 135篇 |
特种医学 | 89篇 |
外科学 | 542篇 |
综合类 | 33篇 |
预防医学 | 48篇 |
眼科学 | 26篇 |
药学 | 47篇 |
肿瘤学 | 96篇 |
出版年
2024年 | 3篇 |
2023年 | 12篇 |
2022年 | 22篇 |
2021年 | 47篇 |
2020年 | 27篇 |
2019年 | 25篇 |
2018年 | 45篇 |
2017年 | 38篇 |
2016年 | 64篇 |
2015年 | 64篇 |
2014年 | 79篇 |
2013年 | 119篇 |
2012年 | 165篇 |
2011年 | 167篇 |
2010年 | 100篇 |
2009年 | 80篇 |
2008年 | 148篇 |
2007年 | 192篇 |
2006年 | 190篇 |
2005年 | 205篇 |
2004年 | 171篇 |
2003年 | 116篇 |
2002年 | 142篇 |
2001年 | 35篇 |
2000年 | 21篇 |
1999年 | 16篇 |
1998年 | 22篇 |
1997年 | 10篇 |
1996年 | 14篇 |
1995年 | 9篇 |
1994年 | 3篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 7篇 |
1990年 | 4篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1977年 | 1篇 |
1973年 | 1篇 |
1971年 | 1篇 |
1957年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有2383条查询结果,搜索用时 15 毫秒
71.
Neslihan Duruturk Eda Tonga Metin Karatas Ersin Doganozu 《Journal of Physical Therapy Science》2015,27(7):2023-2028
[Purpose] To describe the functional consequences of patients with cardiac diseases and
analyze associations between activity limitations and quality of life. [Subjects and
Methods] Seventy subjects (mean age: 60.1±12.0 years) were being treated by Physical
Medicine and Rehabilitation and Cardiology Departments were included in the study.
Activity limitations and participation restrictions as perceived by the individual were
measured by the Canadian Occupational Performance Measure (COPM). The Nottingham Extended
Activities of Daily Living (NEADL) Scale was used to describe limitations in daily living
activities. To detect the impact of activity limitations on quality of life the Nottingham
Health Profile (NHP) was used. [Results] The subjects described 46 different types of
problematic activities. The five most identified problems were walking (45.7%), climbing
up the stairs (41.4%), bathing (30%), dressing (28.6%) and outings (27.1%). The
associations between COPM performance score with all subgroups of NEADL and NHP; total,
energy, physical abilities subgroups, were statistically significant. [Conclusion] Our
results showed that patients with cardiac diseases reported problems with a wide range of
activities, and that also quality of life may be affected by activities of daily living.
COPM can be provided as a patient-focused outcome measure, and it may be a useful tool for
identifying those problems.Key words: Activity limitation, Cardiac diseases, Quality of life 相似文献
72.
The characteristics of cases diagnosed as aspergillosis and Aspergillus spp. strains isolated from the respiratory tract samples in Mycology Laboratory of Trakya University Hospital between January 2002 and May 2006 were investigated. In this period, 137 bronchoalveolar lavages, 95 sputum, nine tracheal aspirates, three lung biopsies and one bronchial biopsy of 85 patients were processed. The samples were incubated in 25 degrees C and 35 degrees C media by culturing on brain heart infusion agar with blood and Sabouraud dextrose agar. Presence of leucocytes and fungal structures were searched in the smear stained by Gram and Giemsa. The patient was defined as probable aspergillosis case, if he/she patient had clinical findings, lung infiltration or fungus ball radiologically, at least one risk factor predisposing to aspergillosis and isolation of Aspergillus spp. in lower respiratory tract samples without finding of other nonmycotic infection. Of 22 patients isolated Aspergillus spp., 13, six, two, one were internalized in chest diseases, haemotology, neurosurgery and oncology clinics, respectively. Seven positive cultures were considered as findings of aspergillosis. Aspergillus fumigatus, Aspergillus flavus and Aspergillus niger were isolated in three, two, and two patients, respectively. Fungal structures were detected in only one sample in the direct microscopical examination. Ages of seven patients, five were males and two were females, were between 15 and 60. Predisposing risk factors were acute leukemia in six patients and lung cancer in one patient. Five patients were neutropenic and one was neutrophylic. Fungus ball was detected in radiological imaging of one patient, had a pulmonary cavitary lesion. Conventional amphotericine B was used in their therapies. Antifungal agents were switched to caspofungin and itraconazole in two and one patients, respectively. Three patients died in four weeks after isolation of Aspergillus spp. Aspergillosis cases were not high in our hospital because of absence of transplantation center for bone marrow or solid organ. 相似文献
73.
Chronic granulomatous disease (CGD) is a rare disorder of phagocytic cell oxidative metabolism. Patients have recurrent infections with catalase-positive organisms and granulomatous lesions throughout the body. Gastric antrum can be an occult site of involvement. We describe a four-year old boy with chronic granulomatous disease who was admitted with the complaints of persistent vomiting and weight loss. Gastric antral narrowing was diagnosed according to radiological findings. Treatment with steroid and antibiotics yielded a good clinical response in 15 days with a relief of the obstruction. This case report emphasizes the beneficial effect of this form of therapy in preventing life-threatening obstruction of vital organs in CGD. 相似文献
74.
The effects of rosiglitazone and metformin on oxidative stress and homocysteine levels in lean patients with polycystic ovary syndrome 总被引:4,自引:0,他引:4
Yilmaz M Bukan N Ayvaz G Karakoç A Törüner F Cakir N Arslan M 《Human reproduction (Oxford, England)》2005,20(12):3333-3340
BACKGROUND: Oxidative stress and hyperhomocysteinaemia are risk factors for cardiovascular diseases. The aim of this study was to assess the effects of rosiglitazone and metformin on cardiovascular disease risk factors such as insulin resistance, oxidative stress and homocysteine levels in lean patients with polycystic ovary syndrome (PCOS). METHODS: Fifty lean patients (BMI <25 kg/m2) with PCOS and 35 healthy subjects were included this study. Serum homocysteine, sex steroids, fasting insulin, fasting glucose and lipid levels were measured. Total antioxidant status (TAS; combines concentrations of individual antioxidants) and malonyldialdehyde concentration (MDA) were determined. Insulin resistance was evaluated by using the homeostasis model insulin resistance index (HOMA-IR), quantitative insulin sensitivity check index (QUICKI), Area under the curve insulin (AUCI) and the insulin sensitivity index (ISI). Patients were divided into two groups. One group was treated with metformin (n = 25) and the other received rosiglitazone (n = 25) for 12 weeks. All measurements were repeated at the end of 12 weeks. RESULTS: Compared with healthy women, those with PCOS had significantly elevated serum MDA, homocysteine, HOMA-IR, AUCI and lipoprotein a levels, and significantly decreased serum TAS, QUICKI and ISI. Serum free testosterone levels showed a significant positive correlation with MDA, AUCI and HOMA-IR, and a negative correlation with TAS, ISI and QUICKI in PCOS patients. HOMA-IR and AUCI significantly decreased, while QUICKI and ISI significantly increased after treatment in both groups. Serum TAS level increased and serum MDA level decreased after the rosiglitazone treatment, but these parameters did not change after the metformin treatment. Serum homocysteine and lipid levels did not change in either group, while serum androgen levels and LH/FSH ratio significantly decreased after the treatment period in only the rosiglitazone-treated group. CONCLUSION: Elevated insulin resistance, oxidative stress and plasma homocysteine levels and changes in serum lipid profile (risk factors for cardiovascular disease) were observed in lean PCOS patients. Rosiglitazone seemed to decrease elevated oxidative stress when compared with metformin treatment in lean PCOS patients. 相似文献
75.
Oxidative stress and enzymatic antioxidant status in patients with nonalcoholic steatohepatitis 总被引:16,自引:0,他引:16
Koruk M Taysi S Savas MC Yilmaz O Akcay F Karakok M 《Annals of clinical and laboratory science》2004,34(1):57-62
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
76.
Didem Yazi Tunc Akkoc Cevdet Ozdemir Ozlem Yesil Metin Aydogan Recep Sancak Nerin N Bahceciler Isil B Barlan 《Annals of allergy, asthma & immunology》2007,98(6):573-579
BACKGROUND: Mycobacteria are being investigated for modulation of inflammation in asthma and atopic disorders by eliciting particularly strong protective TH1 immune responses. OBJECTIVE: To investigate the long-term effects of intratracheally administered Mycobacterium vaccae on an experimental murine model of asthma. METHODS: BALB/c mice were placed in 4 groups: long-term M. vaccae, M. vaccae, asthma, and control groups. All groups but controls were sensitized intraperitoneally and challenged intratracheally with ovalbumin. The long-term M. vaccae and M. vaccae groups were treated with M. vaccae intratracheally simultaneously during challenges. Finally, mice in the long-term M. vaccae group were rechallenged with ovalbumin nebulization 24 days later. Evaluations of lung histopathologic findings and serum cytokine levels were performed. RESULTS: Comparison of the long-term M. vaccae group with the asthma model group revealed that the number of hyperplasic goblet cells in small and large airways (small airway: P < .05; large airways: P < .01) and thickness of basement membrane in large airways were significantly less in the long-term M. vaccae group. Furthermore, numbers of hyperplasic goblet cells in small airways (P < .05) and basement membrane in the large airway (P < .05), as well as inflammation in small airways (P < .01), were significantly less in the M. vaccae group when compared with the asthma model group. Interferon-gamma secretion from splenocytes of the M. vaccae group was significantly higher than the asthma model and long-term M. vaccae groups. CONCLUSION: Intratracheal administration of M. vaccae exerted a long-lasting ameliorating effect on airway histopathologic features of a murine asthma model. 相似文献
77.
Metin N. Gurcan Tony Pan Ashish Sharma Tahsin Kurc Scott Oster Stephen Langella Shannon Hastings Khan M. Siddiqui Eliot L. Siegel Joel Saltz 《Journal of digital imaging》2007,20(2):160-171
This paper describes a Grid-aware image reviewing system (GridIMAGE) that allows practitioners to (a) select images from multiple geographically distributed digital imaging and communication in medicine (DICOM) servers, (b) send those images to a specified group of human readers and computer-assisted detection (CAD) algorithms, and (c) obtain and compare interpretations from human readers and CAD algorithms. The currently implemented system was developed using the National Cancer Institute caGrid infrastructure and is designed to support the identification of lung nodules on thoracic computed tomography. However, the infrastructure is general and can support any type of distributed review. caGrid data and analytical services are used to link DICOM image databases and CAD systems and to interact with human readers. Moreover, the service-oriented and distributed structure of the GridIMAGE framework enables a flexible system, which can be deployed in an institution (linking multiple DICOM servers and CAD algorithms) and in a Grid environment (linking the resources of collaborating research groups). GridIMAGE provides a framework that allows practitioners to obtain interpretations from one or more human readers or CAD algorithms. It also provides a mechanism to allow cooperative imaging groups to systematically perform image interpretation tasks associated with research protocols. 相似文献
78.
Chen TY Zhang D Dragomir A Akay Y Akay M 《Medical & biological engineering & computing》2011,49(5):605-612
We investigated the influence of nicotine exposure and prefrontal cortex (PFC) transections on ventral tegmental areas (VTA)
dopamine (DA) neurons’ firing activities using a time–frequency method based on the continuous wavelet transform (CWT). Extracellular
single-unit neural activity was recorded from DA neurons in the VTA area of rats. One group had their PFC inputs to the VTA
intact, while the other group had the inputs to VTA bilaterally transected immediate caudal to the PFC. We hypothesized that
the systemic nicotine exposure will significantly change the energy distribution in the recorded neural activity. Additionally,
we investigated whether the loss of inputs to the VTA caused by the PFC transection resulted in the cancellation of the nicotine’
effect on the neurons’ firing patterns. The time–frequency representations of VTA DA neurons firing activity were estimated
from the reconstructed firing rate histogram. The energy contents were estimated from three frequency bands, which are known
to encompass the significant modes of operation of DA neurons. Our results show that systemic nicotine exposure disrupts the
energy distribution in PFC-intact rats. Particularly, there is a significant increase in energy contents of the 1–1.5 Hz frequency
band. This corresponds to an observed increase in the firing rate of VTA DA neurons following nicotine exposure. Additionally,
our results from PFC-transected rats show that there is no change in the energy distribution of the recordings after systemic
nicotine exposure. These results indicate that the PFC plays an important role in affecting the activities of VTA DA neurons
and that the CWT is a useful method for monitoring the changes in neural activity patterns in both time and frequency domains. 相似文献
79.
Berrin Papila KUNDAKTEPE Ali Vedat DURGUN Erturul G
KSOY Salih PEKMEZC Metin KAPAN Kaya SARIBEYOLU Mehmet VELDEDEOLU Mehmet ELEVK 《Turkish Journal of Medical Sciences》2021,51(3):1439
Background and aimVascular variations of grafts are handled with various reconstruction techniques in renal transplantation. We aimed to analyze the effects of these reconstruction techniques and sites on patient/graft outcomes.Materials and methodsRenal transplantation cases at the Transplantation Unit of the General Surgery Department, İstanbul University Cerrahpaşa Medical Faculty between January 1st, 2000 and December 31st, 2012 were analyzed retrospectively. Postoperative duplex ultrasound results, urea-creatinine reduction rates, and complications were evaluated.ResultsThere were 228 living-donor transplantation cases evaluated. For single-renal-artery living-donor transplantations, there were 45 end-to-side external iliac artery, 15 end-to-side internal iliac artery, 152 end-to-end internal iliac artery, and 3 end-to-side common iliac artery anastomoses performed. In cases with double-arteries, 3 had end-to-side external iliac artery anastomoses, and 10 had endto-end internal iliac artery anastomoses. No statistically significant differences were found between reconstruction techniques with regard to complications or urea-creatinine reduction rates.ConclusionInternal, external, and common iliac arteries can be safely used for anastomoses. The presence of more than one renal artery creates no short or long-term problems when a side-to-side anastomosis is initially performed. 相似文献
80.
Cyclooxygenase-2 (COX-2) is a prostaglandin synthase that catalyzes the synthesis of prostaglandin G2 and H2. It has been shown that COX-2 plays an important role in tumorigenesis of different tumor types and it is thought to take part in breast carcinogenesis. In the present study, we aimed to investigate the relationship of immunohistochemical COX-2 expression with clinicopathological parameters, including HER-2/neu overexpression in invasive breast carcinoma (IBC).Our study population comprised 10 normal breasts, 25 ductal carcinomas in situ (DCIS), and 51 invasive breast carcinomas. Immunohistochemical overexpressions of COX-2 and HER-2/neu were investigated in sections of formalin-fixed, paraffin-embedded blocks by 3 observers.In normal breast, DCIS and IBC, the COX-2 overexpression rate was 0%, 84%, and 58.8%, respectively. In IBC, COX-2 overexpression had a significant relationship with HER-2/neu overexpression (p = 0.026) and a high histological grade (p = 0.026). COX-2 expression in both DCIS (n = 25) and IBC (n = 51) was significantly higher than in normal breast tissue (p < 0.0001). In addition, the COX-2 expression rate was significantly higher in DCIS than in IBC (p = 0.042).Our results indicated that COX-2 overexpression correlates with aggressive phenotypic features, such as HER-2/neu overexpression and high histological grade in IBC. Increased expression of COX-2 in both DCIS and IBC in comparison to normal breast could indicate a role in breast carcinogenesis. COX-2 overexpression may provide a clinically useful biomarker for estimating tumor aggressiveness. 相似文献