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排序方式: 共有1002条查询结果,搜索用时 15 毫秒
61.
OBJECTIVE: This study was undertaken to evaluate the outcome of in vitro fertilization (IVF) in patients with advanced pelvic endometriosis and previous surgical treatment. STUDY DESIGN: A case controlled study was performed. RESULTS: Patients with the diagnosis of stage IV endometriosis with previous surgical treatment were treated by IVF (group A = 85). An age-matched group of patients (group B = 177) with tubal factor infertility were treated with the same protocol of IVF. In group A, cycle cancellation because of poor response occurred in 29.7% compared with 1.1% in the control group (relative risk 26.03, 95% CI 6.02-112.45). There were 13 (15.3%) clinical pregnancies per stimulated cycle in group A compared with 93 (52.5%) clinical pregnancies in the control group, P <.0001 (odds ratio 0.29, 95% CI 0.15-0.55). CONCLUSION: The outcome of IVF in stage IV endometriosis with previous surgery was significantly lower compared with an age-matched group of tubal factor infertility.  相似文献   
62.
OBJECTIVE: In compare the use of purified follicle-stimulating hormone with that of a preparation containing follicle-stimulating hormone and luteinizing hormone in infertile females undergoing IVF. DESIGN: Open-labelled prospective controlled single-center study. SETTING: Nile Badrawy IVF unit. PARTICIPANTS: 153 infertile females undergoing their first cycle of IVF divided into 2 groups. Interventions: Ovarian stimulation was done with either highly purified FSH for group 1 (n = 75) or human menopausal gonadotrophin group 2 (n = 78) after pituitary desensitization commenced in the midluteal phase of the preceding cycle. Monitoring was performed by ultrasound transvaginal oocyte retrieval followed by IVF and transfer of three embryos. OUTCOMES: Number of oocytes >18 mm at day of hCG, fertilization rate, embryo transfer rate, clinical pregnancy rate and incidence of ovarian hyperstimulation syndrome. RESULTS: The response to ovarian hyperstimulation was similar in both groups. The number of follicles >18 mm achieved at day of hCG was 12.3 +/- 0.9 (mean +/- SEM) following stimulation with 38.3 +/- 0.9 ampoules of Fostimon The Menogon-treated group needed 39.1 +/- 0.8 ampoules to produce 11.6 +/- 0.7 follicles. Fertilization rate (2PN/cell) was 58.6 vs. 64.2% in the Fostimon and Menogon group, respectively (p > 0.05). The number of embryos transferred per woman was 3.1 +/- 0.1 in the Fostimon group and 3.6 +/- 0.1 in the Menogon group. The pregnancy rate per woman was 33.3 vs. 25.6% in the Fostimon- and Menogon-treated groups, respectively (p > 0.05). Miscarriage rate was 16 vs 20%, respectively. However, the incidence of multiple pregnancies was significantly higher in the Fostimon-treated group (32%) vs. 10% only in the Menogon-treated group (p < 0.01). CONCLUSION: Purified FSH yields similar clinical outcome to hMG in terms of oocytes retrieved and clinical pregnancies in a standard IVF regimen.  相似文献   
63.
GnRH antagonist in assisted reproduction: a Cochrane review   总被引:14,自引:0,他引:14  
BACKGROUND: In the present systematic review, we wished to compare the efficacy of gonadotrophin-releasing hormone (GnRH) antagonist and GnRH agonist administration for controlled ovarian hyperstimulation in assisted conception. METHODS: Five randomized controlled trials fulfilled the inclusion criteria. In four studies, the multiple low-dose (0.25 mg) antagonist regimen was applied and, in one study, the single high-dose (3 mg) antagonist regimen was investigated. In all trials, reference treatment included a long protocol of GnRH agonist (buserelin, leuprorelin or triptorelin) starting in the mid-luteal phase of the preceding cycle. RESULTS: In comparison with the long protocol of GnRH agonist, the overall odds ratio for the prevention of premature LH surges was 1.76 [95% confidence interval (CI) 0.75-4.16], which was not statistically significant. There were significantly fewer clinical pregnancies in those treated with GnRH antagonists (OR 0.79; 95% CI 0.63-0.99). There was no statistically significant reduction in incidence of severe ovarian hyperstimulation syndrome between the two regimens (relative risk 0.51; OR 0.79; 95% CI 0.22-1.18). CONCLUSIONS: We concluded that the fixed GnRH antagonist protocol is a short and simple protocol with good clinical outcome, but the lower pregnancy rate compared with the GnRH agonist long protocol and the non-significant difference between both protocols regarding prevention of premature LH surge and prevention of severe ovarian hyperstimulation syndrome necessitates counselling subfertile couples before recommending change from GnRH agonist to antagonist. The clinical outcome may be further improved by developing more flexible antagonist regimens, taking into account individual patient characteristics.  相似文献   
64.
65.
BackgroundThe aim of this review was to evaluate the most used suture materials with regards to their inflammatory response, their bacterial adhesion, and their physical properties when used to close oral wounds.MethodsFour databases (PubMed, Scopus, Dentistry & Oral Sciences, and OVID) were searched to retrieve relevant studies from January 1, 2000, to January 31, 2020.ResultsOut of the 269 articles, only 13 studies were selected as they were relevant and met the systematic review's protocol. These studies showed that almost all suture materials studies (catgut, polyglycolic acid [PGA] sutures, nylon, expanded polytetrafluoroethylene, and silk sutures) caused bacterial adherence and tissue reaction. In nylon and chromic catgut, the number of bacteria accumulated was lowest. Silk and nylon were found to be more impacted than catgut and PGA in terms of physical characteristics such as tensile strength. PGA, on the other hand, was said to be the most susceptible to knot unwinding.ConclusionsFollowing an oral surgical operation, all sutures revealed varied degrees of irritation and microbial accumulation. Nonresorbable monofilament synthetic sutures, however, exhibited less tissue response and less microbial accumulation.  相似文献   
66.
The potent mucosal adjuvant properties of the type II heat-labile enterotoxin LT-IIa of Escherichia coli are dependent upon binding of the B pentamer of the enterotoxin (LT-IIa-B5) to ganglioside receptors on immunocompetent cells. To evaluate the immunomodulatory activities of LT-IIa-B5, in vitro experiments employing bone marrow-derived dendritic cells (BMDC) were performed. Uptake of OVA-FITC, a model antigen (Ag), was enhanced by treatment of BMDC with LT-IIa-B5, but not by treatment of cells with the B pentamer of cholera toxin (CTB). Expression of co-stimulatory molecules (CD40, CD80, CD86, and MHC-II) and cytokines (IL-12p40, TNF-α, and IFN-γ) was increased in BMDC treated with LT-IIa-B5. The capacity of LT-IIa-B5 to enhance Ag uptake and to induce expression of co-stimulatory receptors and cytokines by BMDC was dependent upon expression of TLR2 by the cell. Increased Ag uptake induced by LT-IIa-B5 was correlated with increased Ag-specific proliferation of CD4+ T cells in an in vitro syngeneic DO11.10 CD4+ T cell proliferation assay. These experiments confirm that LT-IIa-B5 exhibits potent immunomodulatory properties which may be exploitable as a non-toxic mucosal adjuvant.  相似文献   
67.
Hypoxic-ischemic encephalopathy (HIE) is a major cause of neonatal morbidity and mortality. Electroencephalography (EEG) and brain magnetic resonance imaging (MRI) are frequently performed in these infants, but the prognostic value of the combined use of EEG and MRI needs additional exploration. The purpose of this study was to investigate, in neonates with HIE, the role of early EEG and conventional MRI in the prediction of infants at risk for persistent encephalopathy at 18 months of age. Thirty-four term infants with HIE were enrolled in this prospective study. EEG was recorded within the first 72 hours after birth and a brain MRI scan was done between 1 and 4 weeks of age. Denver Developmental Screening Test II was performed at 6, 12, and 18 months of age. Three infants (9%) had mild HIE, 21 infants (62%) had moderate HIE, and 10 infants (29%) had severe HIE. The EEG background was normal, moderately, severely, and extremely discontinuous in eight (24%), three (9%), sixteen (47%), and seven (20%) neonates, respectively. EEG background activities correlated significantly with HIE severity (p = 0.0001). MRI findings significantly correlated with EEG background (p = 0.001). Normal MRI scans and minimal basal ganglia lesions were always associated with normal EEG background. Patients with severe basal ganglia and thalamic lesions in MRI (n = 2) had extreme discontinuous EEG background. For the prediction of poor outcomes, abnormal EEG background activity had a sensitivity (Sn) = 100%, a specificity (Sp) = 100%, positive predictive value (PPV) = 100%, and negative predictive value (NPV) = 100%, whereas values of abnormal MRI scans were Sn of 100%, Sp = 43%, PPV = 82%, and NPV=100%. EEG background activity is the best element to predict abnormal outcomes. Severe basal ganglia and thalamic injuries on MRI scans are associated with poor outcomes. Otherwise, MRI does not contribute to the prediction of outcomes at 18 months of age.  相似文献   
68.
Bioadhesive poly(anhydride) nanoparticles coated with mannose (M-NP) or Salmonella Enteritidis derived flagellin (F-NP) were designed to be applied in oral vaccination strategies using ovalbumin (OVA) as antigen model. Nanoparticles formulations (OVA-M-NP, OVA-F-NP and control OVA-NP) were characterized and evaluated in BALB/c mice. OVA-M-NP and OVA-F-NP displayed a size of about 300–400 nm and were efficiently coated with the respective ligand, Systemic and mucosal immune responses reported after S.C. and oral administration, indicated that a single dose of OVA-M-NP and OVA-F-NP, elicited higher and balanced systemic specific antibody responses [IgG1 (Th2-response) and IgG2a (Th1-response)] compared to non-coated ones. In addition, oral immunization using OVA-M-NP or OVAF-NP was able to elicit a higher levels of intestinal secretory IgA compared to S.C. In summary, oral immunization by bioadhesive mannosylated or flagellin nanoparticles demonstrated strong long lasting systemic and mucosal immune responses than the respective non-conjugated vectors.  相似文献   
69.
A collection of 32 botanically identified medicinal plants from the slopes of Mt. Cameroon made by two Swedish settlers in the beginning of the last century is described and the literature is followed up. The drug names were found to be unaltered during the century passed.  相似文献   
70.

Abstract  

A series of novel benzoxepin-derived compounds were synthesized and evaluated for their sedative–hypnotic effect using Phenobarbital-induced sleep test in mice. Compound 6 in which the Phenobarbital moiety was incorporated into the benzoxepin nucleus was the most active one. Molecular modeling, including fitting to a 3D-pharmacophore model using Discovery Studio 2.1 programs into optimized benzodiazepine receptor (hypothesis) showed high fit values. The experimental studies for the in vivo sedative–hypnotic effect of compounds 26 and 11ac were consistent with the molecular modeling.  相似文献   
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