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101.
European Archives of Oto-Rhino-Laryngology - As the lack of consensus in the initial levothyroxine (LT4) dose titration following total thyroidectomy exists, the aim of this study was to identify...  相似文献   
102.
The incorporation of tungsten trioxide (WO3) by various concentrations of graphitic carbon nitride (g-C3N4) was successfully studied. X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and Diffused Reflectance UV-Vis techniques were applied to investigate morphological and microstructure analysis, diffused reflectance optical properties, and photocatalysis measurements of WO3/g-C3N4 photocatalyst composite organic compounds. The photocatalytic activity of incorporating WO3 into g-C3N4 composite organic compounds was evaluated by the photodegradation of both Methylene Blue (MB) dye and phenol under visible-light irradiation. Due to the high purity of the studied heterojunction composite series, no observed diffraction peaks appeared when incorporating WO3 into g-C3N4 composite organic compounds. The particle size of the prepared composite organic compound photocatalysts revealed no evident influence through the increase in WO3 atoms from the SEM characteristic. The direct and indirect bandgap were recorded for different mole ratios of WO3/g-C3N4, and indicated no apparent impact on bandgap energy with increasing WO3 content in the composite photocatalyst. The composite photocatalysts’ properties better understand their photocatalytic activity degradations. The pseudo-first-order reaction constants (K) can be calculated by examining the kinetic photocatalytic activity.  相似文献   
103.
Background and study aimsAscites may be of undetermined origin despite comprehensive study. This study aimed to assess the accuracy and safety of conventional and interventional high-frequency peritoneal ultrasound in the diagnosis of patients with ascites of unclear origin.Patients and methodsA total of 62 patients were prospectively enrolled; they underwent conventional (3.5–5 MHz) and high-frequency (6–8 MHz) transabdominal peritoneal ultrasound to suggest the nature of ascites supplemented by fine needle aspiration cytology (FNAC) of ascites and/or core biopsy of the omentum or other extra-visceral masses for final histopathologic diagnosis. Laparoscopy or laparotomy was needed if biopsy was inconclusive.ResultsUltrasound-guided procedures were diagnostic in 55 (87.7%) patients. Thirty-six (58.1%) were benign, of whom 86% had tuberculous peritonitis, 26 (41.9%) were malignant, of whom 76.9% had peritoneal metastasis. High-frequency ultrasound was able to propose ultrasonographic criteria in a trial to diagnose the nature of ascites. Our proposed ultrasonographic criteria were based on the amount and texture of ascites in addition to the omental and mesenteric features. These were able to suggest the diagnosis with 80.7% sensitivity for malignant ascites and 75% specificity for benign ascites. Moreover, histopathological examination of tissues obtained by ultrasound-guided procedures increased the sensitivity to 88.5% and the specificity to 88.9% in diagnosing malignant and benign disease, respectively, with an overall diagnostic accuracy of 88.6%. These procedures were considered to be safe as only one major (haemoperitoneum) and two minor complications (temporary ascitic fistula) were reported.ConclusionHigh-frequency peritoneal ultrasound together with the minimally invasive ultrasound-guided FNAC/biopsy of extra-visceral lesions may be considered an effective and safe tool in the diagnosis of ascites of undetermined origin.  相似文献   
104.
The optimal dose of vitamin D to optimize bone metabolism in the elderly is unclear. We tested the hypothesis that vitamin D, at a dose higher than recommended by the Institute of Medicine (IOM), has a beneficial effect on bone remodeling and mass. In this double‐blind trial we randomized 257 overweight elderly subjects to receive 1000 mg of elemental calcium citrate/day, and the daily equivalent of 3750 IU/day or 600 IU/day of vitamin D3 for 1 year. The subjects’ mean age was 71 ± 4 years, body mass index 30 ± 4 kg/m2, 55% were women, and 222 completed the 12‐month follow‐up. Mean serum 25 hydroxyvitamin D (25OHD) was 20 ng/mL, and rose to 26 ng/mL in the low‐dose arm, and 36 ng/mL in the high‐dose arm, at 1 year (p < 0.05). Plasma parathyroid hormone, osteocalcin, and C‐terminal telopeptide (Cross Laps) levels decreased significantly by 20% to 22% in both arms, but there were no differences between the two groups for any variable, at 6 or 12 months, with the exception of serum calcitriol, which was higher in the high‐dose group at 12 months. Bone mineral density (BMD) increased significantly at the total hip and lumbar spine, but not the femoral neck, in both study arms, whereas subtotal body BMD increased in the high‐dose group only, at 1 year. However, there were no significant differences in percent change BMD between the two study arms at any skeletal site. Subjects with serum 25OHD <20 ng/mL and PTH level >76 pg/mL showed a trend for higher BMD increments at all skeletal sites, in the high‐dose group, that reached significance at the hip. Adverse events were comparable in the two study arms. This controlled trial shows little additional benefit in vitamin D supplementation at a dose exceeding the IOM recommendation of 600 IU/day on BMD and bone markers, in overweight elderly individuals. © 2017 American Society for Bone and Mineral Research.  相似文献   
105.
Vaziri Sani F, Kaartinen V, El Shahawy M, Linde A, Gritli‐Linde A. Developmental changes in cellular and extracellular structural macromolecules in the secondary palate and nasal cavity of the mouse. Eur J Oral Sci 2010; 118: 221–236. © 2010 The Authors. Journal compilation© 2010 Eur J Oral Sci The aim of this study was to analyse the hitherto largely unknown expression patterns of some specific cellular and extracellular molecules during palate and nasal cavity development. We showed that epithelia of the developing palate and the vomerine epithelium express similar sets of structural proteins. With the exception of keratin 15, which becomes barely detectable in the elevated palatal shelves, nearly all of these proteins become upregulated at the presumptive areas of fusion and in the adhering epithelia of the palate and nasal septum. In vivo and in vitro analyses indicated that reduction in the amount of keratin 15 protein is independent of Tgfβ–Alk5 signalling. Foxa1 expression also highlighted the regionalization of the palatal and nasal epithelia. Owing to the lack of reliable markers of the palatal periderm, the fate of peridermal cells has been controversial. We identified LewisX/stage‐specific embryonic antigen‐1 as a specific peridermal marker, and showed that numerous peridermal cells remain trapped in the medial epithelial seam (MES). The fate of these cells is probably apoptosis together with the rest of the MES cells, as we provided strong evidence for this event. Heparan sulphate, chondroitin‐6‐sulphate, and versican displayed dynamically changing distribution patterns. The hitherto‐unknown innervation pattern of the developing palate was revealed. These findings may be of value for unravelling the pathogenesis of palatal clefting.  相似文献   
106.
107.
ObjectivesTo assess insulin resistance in early untreated rheumatoid arthritis patients and its relation to the clinical, inflammatory and biochemical characteristics of these patients.Patients and methodsSixty-six untreated rheumatoid arthritis (RA) patients with disease duration less than 1 year along with age and sex matched controls were studied. Disease activity score (DAS28) was used to assess disease activity. Plasma levels of C- reactive protein (CRP), glucose, insulin and complete lipid profile were measured. Insulin resistance (IR) was estimated by the homeostasis model assessment for insulin resistance (HOMA-IR).ResultsRA patients revealed high grade systemic inflammation compared to control group p < 0.0001. Patients with high disease activity were more insulin resistant than patients with moderate disease activity P < 0.0001.ConclusionThe findings of the present study showed that early untreated RA patients are characterized by a severe insulin resistant state that is driven primarily by disease activity and systemic inflammation.  相似文献   
108.
Arthritis associated with panniculitis complicating pancreatitis is well described in the literature, usually associated with osteonecrosis. Chondronecrosis has not been reported before in association with pancreatitis. We report a patient with chronic pancreatitis who presented with polyarthritis, panniculitis, osteonecrosis, but in addition had clear evidence of chondronecrosis. We suggest that direct extension of noxious materials from nearby subchondral osteonecrotic bone lesion could be the cause of the osteonecrosis and one of the pathological mechanisms leading to arthritis in patients with pancreatitis.  相似文献   
109.
Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related mortality after lung and stomach cancers. This work was undertaken to investigate some of the biochemical mediators/pathways associated with or implicated in the pathogenesis of HCC. Male albino mice were classified into two groups: normal control group and HCC group. Early stage HCC was induced by injection of diethylnitrosamine (DEN) i.p. 200 mg/kg as a single dose, and after 2 weeks, the mice were given i.p. injection of thioacetamide (TAA) 100 mg/kg twice per week for 4 weeks. Mice were left for further 2 weeks without any treatment, after which, mice were sacrificed; blood and liver samples were collected. Serum was used for determination of activities of glucose-6-phosphate dehydrogenase (G6PDH) and aldolase as well as levels of insulin-like growth factor-1 (IGF-1) and epithelial cadherin (E-cadherin). One portion of the liver was used for histopathological examination and immunohistochemical staining of the tumor suppressor p53 protein. Another portion of the liver was used for determination of citrate synthase activity. Induction of HCC in mice resulted in significant increase in G6PDH and aldolase activities, and E-cadherin level, but significant decrease in IGF-1. HCC mice group showed moderate expression of p53 protein. These results suggest that the molecular pathogenesis of HCC in mice involves reduction of serum level of IGF-1 and increased serum level of E-cadherin accompanied by dysregulation of p53 protein expression. HCC was also associated with reprogrammed metabolic profile shifted toward increased glycolysis and lipogenesis.  相似文献   
110.
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