全文获取类型
收费全文 | 881篇 |
免费 | 66篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 58篇 |
妇产科学 | 39篇 |
基础医学 | 93篇 |
口腔科学 | 19篇 |
临床医学 | 88篇 |
内科学 | 170篇 |
皮肤病学 | 50篇 |
神经病学 | 82篇 |
特种医学 | 23篇 |
外科学 | 159篇 |
综合类 | 17篇 |
预防医学 | 24篇 |
眼科学 | 21篇 |
药学 | 77篇 |
中国医学 | 2篇 |
肿瘤学 | 19篇 |
出版年
2024年 | 2篇 |
2023年 | 8篇 |
2022年 | 16篇 |
2021年 | 25篇 |
2020年 | 25篇 |
2019年 | 21篇 |
2018年 | 25篇 |
2017年 | 30篇 |
2016年 | 39篇 |
2015年 | 47篇 |
2014年 | 42篇 |
2013年 | 50篇 |
2012年 | 65篇 |
2011年 | 68篇 |
2010年 | 40篇 |
2009年 | 36篇 |
2008年 | 81篇 |
2007年 | 88篇 |
2006年 | 72篇 |
2005年 | 53篇 |
2004年 | 44篇 |
2003年 | 29篇 |
2002年 | 18篇 |
2001年 | 8篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1992年 | 1篇 |
1990年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1983年 | 2篇 |
1981年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有952条查询结果,搜索用时 15 毫秒
101.
102.
Unlugenc H Ozalevli M Gunes Y Olguner S Evrüke C Ozcengiz D Akman H 《European journal of anaesthesiology》2006,23(12):1018-1024
BACKGROUND: In this prospective, randomized, double-blind, controlled study, we investigated the sensory, motor and analgesic block characteristics of S(+) ketamine, fentanyl and saline given intrathecally (IT) in addition to 0.5% plain bupivacaine (10 mg) for spinal analgesia. METHODS: Ninety ASA I or II adult patients undergoing Caesarean section were randomly allocated to receive 1.0 mL of 0.9% saline in Group S (n = 30), 0.05 mg kg-1 of S(+) ketamine (1.0 mL) in Group K (n =30) or 25 microg (1.0 mL) of fentanyl in Group F (n =30) following 10 mg of plain bupivacaine 0.5% IT. We recorded onset and duration of sensory and motor block, time to reach the maximal dermatomal level of sensory block and duration of spinal analgesia. RESULTS: The onset time of sensory and motor block was significantly shorter in Groups K and F than in Group S (P < 0.014). Their duration was significantly longer in Group F than in Groups K and S (P < 0.009). The time to reach the maximal dermatomal level of sensory block was significantly shorter in Groups K and F than in Group S (P < 0.001). The duration of spinal analgesia was significantly longer in Group F than in Groups K and S (P < 0.001). CONCLUSION: In patients undergoing Caesarean section with spinal analgesia, the addition of S(+) ketamine (0.05 mg kg-1) IT to 10 mg of spinal plain bupivacaine (0.5%) led to rapid onset of both sensory and motor blockade and enhanced the segmental spread of spinal block without prolonging the duration of spinal analgesia, whereas fentanyl provided prolonged analgesia. 相似文献
103.
Yavuzer G Geler-Külcü D Sonel-Tur B Kutlay S Ergin S Stam HJ 《Archives of physical medicine and rehabilitation》2006,87(4):536-540
OBJECTIVE: To evaluate the effects of neuromuscular electric stimulation (NMES) of the tibialis anterior muscle on motor recovery and gait kinematics of patients with stroke. DESIGN: Randomized, controlled, assessor-blinded trial. SETTING: Rehabilitation ward and gait laboratory of a university hospital. PARTICIPANTS: A total of 25 consecutive inpatients with stroke (mean age, 55y), all within 6 months poststroke and without volitional ankle dorsiflexion. INTERVENTION: Both the NMES group (n=12) and the control group (n=13) participated in a conventional stroke rehabilitation program, 5 days a week for 4 weeks. The NMES group also received 10 minutes of NMES to the tibialis anterior muscle of the paretic limb. MAIN OUTCOME MEASURES: Brunnstrom stages of motor recovery and kinematic characteristics of gait. RESULTS: Brunnstrom stages improved significantly in both groups (P<.05). In total, 58% of the NMES group and 61% of the control group gained voluntary ankle dorsiflexion. Between-group difference of percentage change was not significant (P>.05). Gait kinematics was improved in both groups, but the difference between groups was not significant. CONCLUSIONS: NMES of the tibialis anterior muscle combined with a conventional stroke rehabilitation program was not superior to a conventional stroke rehabilitation program alone, in terms of lower-extremity motor recovery and gait kinematics. 相似文献
104.
E Coban R Sari M Ozdogan F Akcit 《Experimental and clinical endocrinology & diabetes》2005,113(1):35-37
BACKGROUND: Cardiovascular risk associated with impaired fasting glucose has been examined in various studies with conflicting results. During the last 10 years, several risk markers for atherosclerosis such as fibrinogen and D-dimer have been identified. The present study was designed to evaluate plasma fibrinogen and D-dimer levels in patients with impaired fasting glucose compared with normal subjects and those with type 2 diabetes mellitus. METHODS: Age-, sex-, and body mass index-matched 30 normal subjects, 30 patients with impaired fasting glucose (fasting glucose 110 to 125 mg/dl), and 30 patients with type 2 diabetes mellitus (fasting glucose >/= 126 mg/dl) were included in the study. RESULTS: The levels of plasma fibrinogen in patients with type 2 diabetes mellitus, impaired fasting glucose, and normal subjects were 449 (306 - 605) mg/dl, 348 (264 - 468) mg/dl, and 216 (179 - 260) mg/dl, respectively. Patients with impaired fasting glucose had significantly lower plasma fibrinogen levels than patients with type 2 diabetes mellitus (p < 0.05). There were significantly higher plasma fibrinogen levels in patients with impaired fasting glucose than in normal subjects (p < 0.05). The levels of plasma D-dimer in patients with type 2 diabetes mellitus, impaired fasting glucose, and normal subjects were 615 (505 - 768) mg/l, 518 (412 - 664) mg/l, and 424 (356 - 557) mg/l, respectively. Patients with impaired fasting glucose had significantly lower plasma D-dimer levels than patients with type 2 diabetes mellitus (p < 0.05). There were significantly higher plasma D-dimer levels in patients with impaired fasting glucose than in normal subjects (p < 0.05). The levels of plasma fibrinogen and D-dimer were related to fasting glucose in type 2 diabetes mellitus and impaired fasting glucose groups (p < 0.05). We also detected positive correlation between plasma fibrinogen levels and age in study groups (p < 0.05). CONCLUSION: Our data suggest that patients with impaired fasting glucose pose a hypofibrinolytic status and cardiovascular risk, although this was lower than in patients with type 2 diabetes mellitus. 相似文献
105.
The potential to metabolize endogenous and exogenous substances may influence breast cancer development and tumor growth. Therefore we investigated GST activity and the protein expression of glutathione S-transferases (GSTs) isoenzymes known to be involved in the metabolism of endogenous and exogenous carcinogens in breast cancer tissue to obtain new information on their possible role in tumor progression. The interindividual variation in the conjugation of 1-chloro-2,4-dinitrobenzene (CDNB) and of 1,2-epoxy-3-(p-nitrophenoxy) propane (EPNP) with glutathione (GSH) by cytosolic glutathione S-transferases (GSTs) were investigated in human breast matched normal and tumor samples. The GSTA, GSTM, GSTP and GSTT isoenzymes from the crude extracts of matched breast normal and tumor tissues in terms of their immunological properties using western blotting were compared. In most of the samples, the GST activities were higher in the tumor than in the normal cytosolic fractions against both CDNB and EPNP. In the western blotting analysis, it was proved statistically that in normal and tumor epithelial cells, there was difference between GST pi and theta isoenzymes expressions (p0.05). In normal epithelium there was a stronger GST theta expression than in invasive tumor tissues (p=0.013). However, the stronger GST pi expression was observed in tumor epithelium than in normal epithelium in human breast cancers (p=0.000). We found the GSTP protein level and GST activities were higher in the breast tumor than in the normal cytosolic fractions against both CDNB and EPNP, thus implicating a certain biological importance. 相似文献
106.
The utility of serum receptor-binding cancer antigen expressed on SiSo cells in gastrointestinal tract cancers. 总被引:2,自引:0,他引:2
Sahin Coban Hasan Ozkan Seyfettin K?klü Osman Yüksel Muhammed Cem Ko?kar Tarik Akar Necati Ormeci 《Journal canadien de gastroenterologie》2006,20(9):593-596
BACKGROUND: Receptor-binding cancer antigen expressed on SiSo cells (RCAS1) is a novel tumour marker that has been described in various kinds of cancer. The majority of observations include immunohistochemical studies; however, there are not enough data about the utility of this antigen as a serum tumour marker and its tumour specificity. AIM: To measure the serum levels of RCAS1 in patients with gastrointestinal (GI) tract cancers and compare them with other GI tract tumour markers. PATIENTS AND METHODS: Sera collected from patients with GI cancers (14 esophagus, 32 gastric and 36 colon) and from healthy volunteers (30 individuals) were analyzed for RCAS1 and compared with carcinoembryonic antigen (CEA) and cancer antigen 19-9. The relationship between serum RCAS1, tumour stage and tumour grade was also evaluated. RESULTS: Mean serum RCAS1 level was higher in patients with GI tract cancers compared with the control group (P=0.001). Among GI tract cancers, RCAS1 had lowest and highest sensitivity for esophagus and colon cancer diagnosis, respectively. Serum RCAS1 had a higher sensitivity for malignancy, except in the colon, and lower specificity in all groups compared with CEA. In comparison with cancer antigen 19-9, serum RCAS1 was more sensitive but less specific for all GI cancer groups. Mean serum RCAS1 levels were not statistically significant among histopathological tumour types (P>0.05). Although serum RCAS1 levels were significantly higher in cases with lymph node involvement compared with lymph node-negative cases (P=0.009), there was no difference between cases with and without serosal involvement, vascular invasion and distant metastasis; no correlation was found between tumour size and RCAS1 levels. CONCLUSIONS: RCAS1 may be used and combined with CEA as a tumour marker in GI tract cancers. 相似文献
107.
Arda Guler MD Yunus Emre Erata MD Sinem Aydin MD Haci Murat Gunes MD Gamze Babur Guler MD 《Echocardiography (Mount Kisco, N.Y.)》2023,40(9):983-988
With the increase in transcatheter procedures, the use of bioprosthetic valves has become more frequent in clinical practice. However, the optimal antithrombotic management of patients with bioprosthetic valves remains controversial. In this case report, we describe a patient with a bioprosthetic aortic valve who developed a thrombus while receiving effective dose direct oral anticoagulant (DOAC) therapy. A 73-year-old male patient with a bioprosthetic aortic valve replacement 2 years prior presented with a mobile thrombus and early degeneration of the valve, detected during routine follow-up while being treated with apixaban. Although the valve thrombus regressed after switching to a different anticoagulant drug, we observed that the decreased but still high gradient persisted due to the early degeneration. Anticoagulant management of bioprosthetic valve patients demands careful attention. Although evidence supporting the use of DOACs is growing, close patient follow-up and further evaluation in case of doubt remain critical. The development of a thrombus in a bioprosthetic valve patient who is receiving anticoagulation therapy, as in this case, highlights the need for optimal management to prevent thromboembolic complications and valve degeneration. 相似文献
108.
109.
Papasani MR Gensure RC Yan YL Gunes Y Postlethwait JH Ponugoti B John MR Jüppner H Rubin DA 《Endocrinology》2004,145(11):5294-5304
Although the PTH type 2 receptor (PTH2R) has been isolated from mammals and zebrafish, only its mammalian agonist, tuberoinfundibular peptide 39 (TIP39), has been characterized thus far. To determine whether zebrafish TIP39 (zTIP39) functions similarly with the zebrafish PTHR (zPTH2R) and human PTH2Rs and to determine its tissue-specific expression, fugu (Takifugu rubripes) and zebrafish (Danio rerio) genomic databases were screened with human TIP39 (hTIP39) sequences. A single TIP39 gene was identified for each fish species, which showed significant homology to mammalian TIP39. Using standard molecular techniques, we isolated cDNA sequences encoding zTIP39. The fugu TIP39 precursor was encoded by a gene comprising at least three exons. It contained a hydrophobic signal sequence and a predicted prosequence with a dibasic cleavage site, similar to that found in mammalian TIP39 ligands. Phylogenetic analyses suggested that TIP39 forms the basal group from which PTH and PTHrP have been derived. Functionally, subtle differences in potency could be discerned between hTIP39 and zTIP39. The human PTH2R and zPTH2R were stimulated slightly better by both hTIP39 and zTIP39, whereas zTIP39 had a higher potency at a previously isolated zPTH2R splice variant. Whole-mount in situ hybridization of zebrafish revealed strong zTIP39 expression in the region of the hypothalamus and in the heart of 24- and 48-h-old embryos. Similarly, zPTH2R expression was highly expressed throughout the brain of 48- and 72-h-old embryos. Because the mammalian PTH2R was also most abundantly expressed in these tissues, the TIP39-PTH2R system may serve conserved physiological roles in mammals and fishes. 相似文献
110.
Iron deficiency anemia in the elderly: prevalence and endoscopic evaluation of the gastrointestinal tract in outpatients 总被引:1,自引:0,他引:1
Iron deficiency anemia (IDA), mostly due to chronic occult bleeding from the gastrointestinal tract, is a common problem in the elderly. This study aimed to determine the prevalence of IDA in the elderly and to investigate the gastrointestinal tract in elderly patients with IDA. 1,388 patients over 65 years were prospectively evaluated for IDA in our outpatient clinic. IDA was defined if decreased hemoglobin concentrations (<13 g/dl for men and <12 g/dl for women) were associated with low serum ferritin levels (<15 ng/ml in men and <9 ng/ml in women). We evaluated the gastrointestinal system of all patients with IDA by upper gastrointestinal endoscopy and colonoscopy regardless of fecal occult blood loss. The prevalence of anemia was found to be 25% (n = 347) in our study population, and 30.5% (n = 106) of these patients with anemia had iron deficiency. Upper gastrointestinal endoscopy and colonoscopy were performed in 96 patients with IDA. Fifty-eight upper gastrointestinal system lesions (55 patients, 57.3%) and 27 colonic lesions (26 patients, 27.1%) were detected. We diagnosed gastrointestinal malignancy in 15 (15.6%) elderly patients with IDA (8 colon, 1 esophageal and 6 gastric cancers). IDA is a common problem in elderly patients; consequently, before iron replacement therapy, patients should be thoroughly investigated regarding a possible association with gastrointestinal malignancy. 相似文献