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   7385篇
  免费   487篇
  国内免费   75篇
耳鼻咽喉   64篇
儿科学   163篇
妇产科学   347篇
基础医学   876篇
口腔科学   103篇
临床医学   836篇
内科学   1721篇
皮肤病学   73篇
神经病学   544篇
特种医学   403篇
外科学   956篇
综合类   123篇
一般理论   3篇
预防医学   374篇
眼科学   158篇
药学   547篇
中国医学   43篇
肿瘤学   613篇
  2023年   46篇
  2022年   81篇
  2021年   192篇
  2020年   91篇
  2019年   157篇
  2018年   206篇
  2017年   146篇
  2016年   119篇
  2015年   229篇
  2014年   291篇
  2013年   375篇
  2012年   572篇
  2011年   520篇
  2010年   304篇
  2009年   322篇
  2008年   451篇
  2007年   382篇
  2006年   381篇
  2005年   395篇
  2004年   356篇
  2003年   289篇
  2002年   234篇
  2001年   215篇
  2000年   183篇
  1999年   188篇
  1998年   57篇
  1997年   37篇
  1996年   38篇
  1995年   44篇
  1994年   31篇
  1993年   20篇
  1992年   106篇
  1991年   76篇
  1990年   79篇
  1989年   57篇
  1988年   70篇
  1987年   71篇
  1986年   62篇
  1985年   64篇
  1984年   65篇
  1983年   31篇
  1982年   23篇
  1979年   37篇
  1978年   26篇
  1977年   23篇
  1976年   17篇
  1975年   33篇
  1974年   23篇
  1973年   19篇
  1971年   17篇
排序方式: 共有7947条查询结果,搜索用时 15 毫秒
81.
82.
Optimal therapy for patients with acute myeloid leukemia (AML) in first complete remission (CR-1) remains the subject of debate: with the possibilities of chemotherapy alone, autologous (auto) or allogeneic (allo) hematopoietic stem cell transplantation (HSCT). We undertook a retrospective analysis of AML patients aged below 46 years and in CR-1, who had undergone auto- or allo-HSCT in our institution, to determine the factors associated with a better outcome. Between September 1985 and April 2003, 81 patients underwent autologous (n = 29) or allogeneic (n = 52) HSCT in CR-1. With a median follow-up of 10 years, the probability of 15-year overall survival (OS) was 51%[95% confidence interval (CI) = 32 - 70%] for auto-HSCT vs. 55% (95% CI = 42 - 69) for allo-HSCT, respectively (P = 0.92). The cumulative incidence of relapse at 3 years was 49% (95% CI = 30 - 67) (auto) vs. 21% (95% CI = 10 - 30) (allo), respectively. Non-relapse-related mortality at 3 years was 5% (95% CI = 0 - 14) (auto) vs. 17% (95% CI = 7 - 28) (allo), respectively. This retrospective analysis confirmed that auto- and allo-HSCT led to similar OS. The significantly lower incidence of relapse amongst allograft recipients was balanced by an increased incidence of death in CR.  相似文献   
83.
84.
The high accessibility to healthcare and increasing awareness of hepatocellular carcinoma (HCC) surveillance after sustained virologic response (SVR) to HCV treatment allow early detection of operable HCC in Taiwan. However, the effects of achieving SVR on patient characteristics and surgical outcomes after curative resection remain elusive. We aimed to compare the clinical presentation and postoperative prognosis among patients with early-stage HCV-related HCC and different viral status. We retrospectively analyzed 208 patients with BCLC stage 0 or A-HCC, including 44 patients who remained HCV viremic, 90 patients who developed HCC after achieving SVR (post-SVR HCC), and 74 patients who subsequently achieved SVR after resection. Patients with post-SVR HCC had a lower degree of hepatitis and better liver function than those who achieved SVR or remained viremic after resection. Notably, 75.6% of patients with post-SVR HCC did not have cirrhosis. Patients with post-SVR HCC and those achieving SVR after resection exhibited comparable recurrence rates and recurrence-free survival, while patients with persistent viremia had the worst surgical outcomes. We concluded that patients with post-SVR HCC had a better liver function but similar surgical outcomes compared with patients who achieved SVR after resection. The low prevalence of cirrhosis in patients with post-SVR HCC highlights the importance of regular surveillance after SVR.  相似文献   
85.
Intrahepatic cholangiocarcinoma (iCCA) is an adenocarcinoma arising from the intrahepatic bile duct and accounts for the second highest incidence of primary liver cancers after hepatocellular carcinoma. The lack of effective treatment leads to a poor prognosis for advanced iCCA, so new targeted therapy is needed. The impairment of wild-type (WT) p53 tumor suppressor function by its negative regulators frequently occurs in iCCA. Therefore, restoration of WT p53 function by inhibiting its negative regulators is a therapeutic strategy being explored for cancer treatment. Combining an MDM2 inhibitor (MDM2i, RG7388) to stabilize p53 and a WIP1 inhibitor (WIP1i, GSK2830371) to increase p53 phosphorylation enhances p53 function. The combination of MDM2 and WIP1 inhibitors has been reported in several cancer types but in vivo studies are lacking. In the current study, liver adenocarcinoma cell lines, RBE and SK-Hep-1, were treated with RG7388 alone and in combination with GSK2830371. Cell proliferation, clonogenicity, protein and mRNA expressions, and cell cycle distribution were performed to investigate the effect and mechanism of growth suppression. To evaluate the antitumor efficacy of RG7388 and GSK2830371 in vivo, SK-Hep-1 xenografts in NOD-SCID mice were treated with combination therapy for two weeks. The combination of MDM2i and WIP1i significantly increased the growth inhibition, cytotoxicty, p53 protein expression, and phosphorylation (Ser15), leading to transactivation of downstream targets (p21WAF1 and MDM2). The in vivo results demonstrated that the combination treatment can significantly inhibit tumor growth. In this study, the liver adenocarcinoma cell lines responded to combination treatment via reactivation of p53 function evidenced by increased p53 expression, phosphorylation and expression of its downstream targets. This efficacy was also demonstrated in vivo. The current research provides a novel strategy for targeting the p53 pathway in liver adenocarcinoma that warrants further investigation.  相似文献   
86.
Chimeric antigen receptor (CAR) T cells targeting B‐cell maturation antigen have shown positive responses in patients with multiple myeloma (MM). The phase 2 portion of the CARTITUDE‐1 study of ciltacabtagene autoleucel (cilta‐cel) included a cohort of Japanese patients with relapsed/refractory MM. Following a conditioning regimen of cyclophosphamide (300 mg/m2) and fludarabine (30 mg/m2), patients received a single cilta‐cel infusion at a target dose of 0.75 × 106 (range, 0.5–1.0 × 106CAR‐positive viable T cells/kg). The primary endpoint was overall response rate (ORR; defined as partial response or better) by International Myeloma Working Group criteria. A key secondary endpoint was the rate of very good partial response (VGPR) or better (defined as VGPR, complete response, stringent complete response). This first analysis was performed at 6 months after the last patient received cilta‐cel. Thirteen patients underwent apheresis, nine of whom received cilta‐cel infusion. Eight patients who received cilta‐cel at the target dose responded, yielding an ORR of 100%. Seven of eight (87.5%) patients achieved a VGPR or better. One additional patient who received a below‐target dose of cilta‐cel also achieved a best response of VGPR. MRD negativity (10−5 threshold) was achieved in all six evaluable patients. Eight of nine (88.9%) patients who received cilta‐cel infusion experienced a grade 3 or 4 adverse event, and eight (88.9%) patients experienced cytokine release syndrome (all grade 1 or 2). No CAR‐T cell neurotoxicity was reported. A positive benefit/risk profile for cilta‐cel was established for heavily pretreated Japanese patients with relapsed or refractory MM.  相似文献   
87.
The antinociception produced by pentazocine, diphenhydramine, promethazine, chlorpheniramine, cyclizine and chlorcyclizine in the rat has been measured with a low-temperature (51.5 degrees C) hot-plate from 15 to 75 min following drug administration. The mean reaction times measured at 15 min and the area under the antinociception curves following administration of pentazocine (5 to 30 mg/kg) were linear. Diphenhydramine, chlorpheniramine, promethazine, cyclizine, and chlorcyclizine showed mild antinociceptive potency. The antinociception produced by SC pentazocine (5 and 10 mg/kg) was potentiated, rather than in a simple additive manner, by simultaneous IP administration of 20 mg/kg of diphenhydramine, promethazine, cyclizine, or chlorpheniramine, but not by chlorcyclizine. After concurrent administration of pentazocine and diphenhydramine, diphenhydramine did not alter pentazocine concentrations in the brain and plasma 15 to 75 min following drug administration, nor did pentazocine change diphenhydramine concentrations. Results of this study demonstrate that pentazocine antinociception can be potentiated by several antihistamines and that the potentiation was not due to a mutual effect on metabolism but rather through an as yet undefined mechanism.  相似文献   
88.
BACKGROUND/OBJECTIVE: As prior studies analysed predictive factors for various post-laminectomy spinal deformities in mixed spinal regions, age groups or pathologies, their validity and conclusions were unclear. The objective of this study was to determine predictive factors for worsened cervical or thoracic spinal sagittal alignment following laminectomy or laminotomy for primary intramedullary spinal cord tumours in children. METHODS: In this retrospective study, patients treated between 1980 and 1998 were reviewed. Changes in spinal alignment at the last follow-up compared to the pre-operative state were studied. Factors analysed were age, pre-operative spinal alignment, procedure types (laminectomy or laminoplasty), number of laminae operated, surgery of C2 or T1 laminae, histological grade, presence of post-operative neurological deficit and post-operative radiotherapy. RESULTS: There were 27 patients. The mean age was 5.6 years (range 1.3-14.0 years), and the mean duration of follow-up was 3.7 years (range 0.075-9.9 years). In the cervical-cervicothoracic surgical group (n = 12), alignment worsened post-operatively in 3 patients. The number of laminae operated upon had a statistically significant impact on the development of post-operative kyphosis (p = 0.07). In the thoracic-thoracolumbar surgical group (n = 15), alignment worsened in 9 patients. Procedure types were statistically significantly different, with laminectomy associated with an increased risk of post-operative kyphosis (p = 0.01). All 5 patients who had spinal fusion for worsened post-operative alignment were in the thoracic-thoracolumbar group; no patients in the cervical-cervicothoracic group required spinal fusion (p = 0.047). Other predictive factors did not reach statistical significance (p > 0.05). CONCLUSIONS: Worsened spinal sagittal alignment following laminectomy or laminoplasty and the need for spinal fusion is more common in the thoracic-thoracolumbar region than in the cervical-cervicothoracic region. In the cervical-cervicothoracic region, operation on a greater number of laminae tends to increase the risk of worsened alignment. In the thoracic-thoracolumbar region, laminectomy is associated with worsened alignment, while laminoplasty reduces this risk; also, pre-operative kyphotic deformity tends to increase the risk of worsened alignment post-operatively.  相似文献   
89.
To examine the effect of a soybean oil emulsion on essential fatty acid, lipid, and glucose metabolism, preterm infants were randomized to receive 0.5 g/kg/d lipid for 5 days (n = 10, group 1) or 0.5 increased to 2.0 g/kg/d over 5 days (n = 11, group 2). Triene/tetraene ratios did not change in group 1, but decreased in group 2. In both groups, plasma phospholipid linoleate (percent and micrograms per milliliter) increased, the increase being greater in group 2. In both groups, percent content of arachidonate and 5,8,11-eicosatrienoate decreased, and that of oleate remained unchanged. In contrast, absolute content of arachidonate and oleate tended to increase, and that of 5,8,11-eicosatrienoate remained unchanged. At a lipid intake of 0.5 g/kg/d, no infants had hyperlipemia. When lipid intake exceeded 1.0 g/kg/d, the frequency of hypertriglyceridemia (triglycerides greater than 200 mg/dL) and free fatty acidemia, with the free fatty acid/molar albumin ratio exceeding 6:1, increased. Plasma glycerol increased slightly, but was substantially less than the rise in enzymatically determined triglycerides. Hyperglycemia was self-limiting and did not require alteration in dextrose intake. Thus, (1) infusion of a soybean oil emulsion at 0.5 to 2.0 g/kg/d maintains essential fatty acid status and phospholipid arachidonate concentrations; (2) significant hyperlipemia occurs when lipid intake exceeds 1.0 g/kg/d; (3) hyperglycemia associated with lipid infusion tends to be self-limiting and may not require alteration in lipid or dextrose intake; and (4) enzymatically determined triglycerides may be used to monitor lipid tolerance, provided that allowance is made for a small but systematic overestimation resulting from the rise in plasma glycerol.  相似文献   
90.
In this paper, comparative studies of hydrophilic and hydrophobic mesoporous silica particles (MSPs) on the dielectric properties of their derivative polyester imide (PEI) composite membranes were investigated. A series of hydrophilic and hydrophobic MSPs were synthesized with the base-catalyzed sol-gel process of TEOS, MTMS, and APTES at a distinctive feeding ratio with a non-surfactant template of D-(-)-Fructose as the pore-forming agent. Subsequently, the MSPs were blended with the diamine of APAB, followed by introducing the dianhydride of TAHQ with mechanical stirring for 24 h. The obtained viscous solution was subsequently coated onto a copper foil, 36 μm in thickness, followed by performing thermal imidization at specifically programmed heating. The dielectric constant of the prepared membranes was found to show an obvious trend: PEI containing hydrophilic MSPs > PEI > PEI containing hydrophobic MSPs. Moreover, the higher the loading of hydrophilic MSPs, the higher the value of the dielectric constant and loss tangent. On the contrary, the higher the loading of hydrophobic MSPs, the lower the value of the dielectric constant with an almost unchanged loss tangent.  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