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991.
The aim of this study was to assess structural indices from high-resolution peripheral quantitative computed tomography (HR-pQCT)
images of the human proximal femur along with areal bone mineral density (aBMD) and compare the relationship of these parameters
to bone strength in vitro. Thirty-one human proximal femur specimens (8 men and 23 women, median age 74 years, range 50–89)
were examined with HR-pQCT at four regions of interest (femoral head, neck, major and minor trochanter) with 82 μm and in
a subgroup (n = 17) with 41 μm resolution. Separate analyses of cortical and trabecular geometry, volumetric BMD (vBMD), and microarchitectural
parameters were obtained. In addition, aBMD by dual-energy X-ray absorptiometry (DXA) was performed at conventional hip regions
and maximal compressive strength (MCS) was determined in a side-impact biomechanical test. Twelve cervical and 19 trochanteric
fractures were confirmed. Geometry, vBMD, microarchitecture, and aBMD correlated significantly with MCS, with Spearman’s correlation
coefficients up to 0.77, 0.89, 0.90, and 0.85 (P < 0.001), respectively. No differences in these correlations were found using 41 μm compared to 82 μm resolution. In multiple
regression analysis of MCS, a combined model (age- and sex-adjusted) with aBMD and structural parameters significantly increased
R
2 values (up to 0.90) compared to a model holding aBMD alone (R
2 up to 0.78) (P < 0.05). Structural parameters and aBMD are equally related to MCS, and both cortical and trabecular structural parameters
obtained from HR-pQCT images hold information on bone strength complementary to that of aBMD. 相似文献
992.
Gastropericardial fistula is an acquired disorder presenting as an abnormal communication between the stomach and the pericardium, with a rare incidence and extremely high mortality rate. We recently experienced a case of life-threatening gastropericardial fistula occurring as an unusual complication after an esophagectomy with an esophagogastrostomy for esophageal cancer treatment. A 68-year-old man with a history of esophagectomy and esophagogastrostomy using the gastric pedicle for the esophageal cancer 13 years ago, visited the hospital with a complaint of dyspnea for 3 days. Chest roentgenogram, computed tomographic scan, and endoscopy showed a pneumopericardium and huge ulcer with central perforation in the posterior wall of the gastric pedicle. 相似文献
993.
994.
Maria H Kim Alick C Mazenga Xiaoying Yu Saeed Ahmed Mary E Paul Peter N Kazembe Elaine J Abrams 《Journal of the International AIDS Society》2017,20(1)
Introduction : Globally adolescents and young adults account for more than 40% of new HIV infections, and HIV‐related deaths amongst adolescents increased by 50% from 2005 to 2012. Adherence to antiretroviral therapy (ART) is critical to control viral replication and preserve health; however, there is a paucity of research on adherence amongst the growing population of adolescents living with HIV/AIDS (ALHIV) in Southern Africa. We examined levels of self‐reported ART adherence, barriers to adherence, and factors associated with non‐adherence amongst ALHIV in Malawi. Methods : Cross‐sectional study of 519 ALHIV (12–18 years) attending two large HIV clinics in central and south‐eastern Malawi. Participants self‐reported missed doses (past week/month), barriers to adherence, and completed questionnaires on past traumatic events/stressors, disclosure, depression, substance use, treatment self‐efficacy, and social support. Biomedical data were retrieved from existing medical records. Multivariate logistic regression was performed to identify factors independently associated with self‐reported ART adherence (7 day recall). Results : The mean age of participants (SD) was 14.5 (2) years and 290 (56%) were female. Of the 519 participants, 153 (30%) reported having missed ART doses within the past week, and 234 (45%) in the past month. Commonly reported barriers to adherence included forgetting (39%), travel from home (14%), busy with other things (11%), feeling depressed/overwhelmed (6%), feeling stigmatized by people outside (5%) and within the home (3%). Factors found to be independently associated with missing a dose in the past week were drinking alcohol in the past month (OR 4.96, 95% CI [1.41–17.4]), missed clinic appointment in the past 6 months (OR 2.23, 95% CI [1.43–3.49]), witnessed or experienced violence in the home (OR 1.86, 95% CI [1.08–3.21]), and poor treatment self‐efficacy (OR 1.55 95% CI [1.02–2.34]). Sex and age were not associated with adherence. Conclusions : In our study, nearly half of all ALHIV reported non‐adherence to ART in the past month. Violence in the home or alcohol use in the past year as well as poor treatment self‐efficacy were associated with worse adherence. Sub‐optimal adherence is a major issue for ALHIV and compromise treatment outcomes. Programmes specifically tailored to address those challenges most pertinent to ALHIV may help improve adherence to ART. 相似文献
995.
Kiluk JV Lee MC Park CK Meade T Minton S Harris E Kim J Laronga C 《The breast journal》2011,17(5):503-509
National Comprehensive Cancer Network (NCCN) guidelines for female breast cancer treatment and surveillance are well established, but similar guidelines on male breast cancers are less recognized. As an NCCN institution, our objective was to examine practice patterns and follow-up for male breast cancer compared to established guidelines for female patients. After Institutional Review Board approval, a prospective breast database from 1990 to 2009 was queried for male patients. Medical records were examined for clinico-pathological factors and follow-up. The 5-year survival rates with 95% confidence intervals were estimated using Kaplan-Meier method and Greenwood formula. Of the 19,084 patients in the database, 73 (0.4%) were male patients; 62 had complete data. One patient had bilateral synchronous breast cancer. The median age was 68.8 years (range 29-85 years). The mean/median invasive tumor size was 2.2/1.6 cm (range 0.0-10.0 cm). All cases had mastectomy (29 with axillary node dissection, 23 with sentinel lymph node biopsy only, 11 with sentinel node biopsy followed by completion axillary dissection). Lymph node involvement occurred in 25/63 (39.7%). Based on NCCN guidelines, chemotherapy, hormonal therapy, and radiation are indicated in 34 cases, 62 cases, and 14 cases, respectively. Only 20/34 (59%) received chemotherapy, 51/62 (82%) received hormonal therapy, and 10/14 (71%) received post-mastectomy radiation. Median follow-up was 26.2 months (range: 1.6-230.9 months). The 5-year survival estimates for node positive and negative diseases were 68.5% and 87.5%, respectively (p = 0.3). Despite the rarity of male breast cancer, treatment options based on current female breast tumors produce comparable results to female breast cancer. Increased awareness and a national registry for patients could help improve outcomes and tailor treatment recommendations to the male variant. 相似文献
996.
The roles of sphingosine kinases SK1 and SK2 in ischemia-reperfusion injury have not been fully elucidated since studies have found beneficial effects of SK1 while others showed no role in this injury. To help resolve this, we used SK1 or SK2 knockout mice and confirmed that renal ischemia-reperfusion injury induced SK1, but not SK2, in the kidneys. Furthermore, knockout or pharmacological inhibition of SK1 increased injury after renal ischemia-reperfusion injury. In contrast, lack of SK2 conferred renal protection following injury. In addition, we used lentiviral gene delivery to selectively express enhanced green fluorescent protein (EGFP) or human SK1 coexpressed with EGFP (EGFP-huSK1) in the kidney. Mice with kidney-specific overexpression of EGFP-huSK1 had significantly improved renal function with lower plasma creatinine, renal necrosis, apoptosis, and inflammation. Moreover, EGFP-huSK1 overexpression in cultured human proximal tubule (HK-2) cells protected against peroxide-induced necrosis. Selective overexpression of EGFP-huSK1 led to increased HSP27 mRNA and protein expression in vivo and in vitro. Functional protection as well as induction of HSP27 with EGFP-huSK1 overexpression in vivo was blocked with sphingosine-1-phosphate-1 receptor(1) (S1P(1)) antagonism. Thus, our findings suggest that SK1 is renoprotective by S1P(1) activation and perhaps HSP27 induction. Kidney-specific expression of SK1 through lentiviral delivery may be a viable therapeutic option to attenuate renal ischemia-reperfusion injury. 相似文献
997.
Parikh CR Devarajan P Zappitelli M Sint K Thiessen-Philbrook H Li S Kim RW Koyner JL Coca SG Edelstein CL Shlipak MG Garg AX Krawczeski CD;TRIBE-AKI Consortium 《Journal of the American Society of Nephrology : JASN》2011,22(9):1737-1747
Acute kidney injury (AKI) occurs commonly after pediatric cardiac surgery and associates with poor outcomes. Biomarkers may help the prediction or early identification of AKI, potentially increasing opportunities for therapeutic interventions. Here, we conducted a prospective, multicenter cohort study involving 311 children undergoing surgery for congenital cardiac lesions to evaluate whether early postoperative measures of urine IL-18, urine neutrophil gelatinase-associated lipocalin (NGAL), or plasma NGAL could identify which patients would develop AKI and other adverse outcomes. Urine IL-18 and urine and plasma NGAL levels peaked within 6 hours after surgery. Severe AKI, defined by dialysis or doubling in serum creatinine during hospital stay, occurred in 53 participants at a median of 2 days after surgery. The first postoperative urine IL-18 and urine NGAL levels strongly associated with severe AKI. After multivariable adjustment, the highest quintiles of urine IL-18 and urine NGAL associated with 6.9- and 4.1-fold higher odds of AKI, respectively, compared with the lowest quintiles. Elevated urine IL-18 and urine NGAL levels associated with longer hospital stay, longer intensive care unit stay, and duration of mechanical ventilation. The accuracy of urine IL-18 and urine NGAL for diagnosis of severe AKI was moderate, with areas under the curve of 0.72 and 0.71, respectively. The addition of these urine biomarkers improved risk prediction over clinical models alone as measured by net reclassification improvement and integrated discrimination improvement. In conclusion, urine IL-18 and urine NGAL, but not plasma NGAL, associate with subsequent AKI and poor outcomes among children undergoing cardiac surgery. 相似文献
998.
This study was designed to determine the optimal dose of remifentanil required for the successful insertion of Streamlined Liner of the Pharynx Airway (SLIPA) and to compare it to that required for laryngeal mask airway (LMA) insertion in patients receiving a propofol infusion at a standard effect-site concentration. Fifty-eight patients scheduled to undergo general anaesthesia were randomly assigned to either the SLIPA (n = 29) or LMA (n = 29) group. All patients were premedicated with midazolam 0.05 mg x kg(-1) and glycopyrrolate 0.004 mg x kg(-1) intramuscularly. After the administration of lignocaine 1 mg x kg(-1) intravenously, a propofol infusion was started at an effect-site concentration of 3.5 microg x ml(-1) with a remifentanil infusion without a neuromuscular blocking agent. The remifentanil dose was determined by the modified up-and-down method starting in each group at 4 ng x ml(-1). Six minutes after induction, the airway device was inserted. Airway device insertion was classified as 'success' or 'failure' based on patient response. From the isotonic regression analysis and bootstrap distribution, the EC50 of remifentanil for SLIPA and LMA were 0.93 ng x ml(-1) (95% confidence interval [CI] 0.81 to 1.50 ng x ml(-1) and 1.36 ng x ml(-1) (95% CI 1.19 to 2.06 ng x ml(-1)) respectively, and the EC95 for SLIPA and LMA insertions were 1.90 ng x ml(-1) (95% CI 1.39 to 1.95) and 2.43 ng x ml(-1) (95% CI 1.80 to 2.46 ng x ml(-1)) respectively. Using the 83% CIs from the bootstrap distribution, EC50 for SLIPA was significantly less than that of LMA (0.83 to 1.23 vs 1.26 to 2.00, respectively) (P < 0.05). These findings suggest that the insertion of SLIPA needs about a 32% lower depth of anaesthesia than LMA insertion. 相似文献
999.
Hwangbo Y Jang JY Kim HJ Kim YW Park SD Shim J Dong SH Kim HJ Kim BH Chang YW Chang R 《Surgery today》2011,41(8):1085-1090
Colonic gastrointestinal stromal tumors (GISTs) account for only 5%-10% of tumors arising in the digestive tract. Spontaneous rupture is a very rare manifestation of a GIST; however, we report what to our knowledge is the first documented case of pneumoretroperitoneum caused by the rupture of a GIST. A 77-year-old woman was admitted to our hospital with acute abdominal pain and hematochezia. Colonoscopy showed luminal narrowing in the sigmoid colon, but no definite mucosal defect. Computed tomography (CT) showed an air-containing heterogeneous mass, 9.7 × 9.3 cm, in the pelvic cavity and a small amount of air in the retroperitoneum. Emergency laparotomy revealed a ruptured sigmoid colonic GIST with localized peritonitis. Pathologic examination confirmed that the tumor was composed mainly of round epithelioid cells. It was immunohistochemically positive for CD34 and negative for C-kit protein. This report describes how we successfully managed pneumoretroperitoneum with localized peritonitis caused by the spontaneous rupture of an epithelioid GIST originating from the sigmoid colon. 相似文献
1000.
Angiogenesis is a necessary process for tumor progression and is driven through molecular interactions between cancer cells and neighboring vascular endothelial cells. The primary mediators of angiogenesis are the vascular endothelial growth factors and their respective receptors on endothelial cells. There are several U.S. Food and Drug Administration-approved anti-angiogenic agents in clinical use. In head and neck cancer there are clinical trials assessing the efficacy of anti-angiogenic agents in combination with chemoradiation therapy. Although the aforementioned growth factors and receptors have been traditionally viewed as anti-angiogenic targets, there are concomitant efforts to understand the role these molecules play within the tumor cells. In this review, we first discuss the biology of angiogenic proteins and the targeting of angiogenic molecules for cancer treatment. We summarize the current clinical trials of anti-angiogenic therapies in head and neck squamous cell carcinoma. Finally, the additional role these molecules play in tumor progression independent of angiogenesis is discussed. 相似文献