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61.

Purpose

Surgical processes are generally only studied by identifying differences in populations such as participants or level of expertise. But the similarity between this population is also important in understanding the process. We therefore proposed to study these two aspects.

Methods

In this article, we show how similarities in process workflow within a population can be identified as sequential surgical signatures. To this purpose, we have proposed a pattern mining approach to identify these signatures.

Validation

We validated our method with a data set composed of seventeen micro-surgical suturing tasks performed by four participants with two levels of expertise.

Results

We identified sequential surgical signatures specific to each participant, shared between participants with and without the same level of expertise. These signatures are also able to perfectly define the level of expertise of the participant who performed a new micro-surgical suturing task. However, it is more complicated to determine who the participant is, and the method correctly determines this information in only 64% of cases.

Conclusion

We show for the first time the concept of sequential surgical signature. This new concept has the potential to further help to understand surgical procedures and provide useful knowledge to define future CAS systems.
  相似文献   
62.
It is not clear that how long the affected fetuses can tolerate fetomaternal hemorrhage (FMH). Incidental serial measurements of the fetal peak systolic velocity of the middle cerebral artery and the retrospective analysis of stocked blood available incidentally indicated that our patient had suffered from FMH for at least 2 weeks prior to delivery.  相似文献   
63.
Journal of Gastroenterology - This multicenter prospective study (UMIN000019958) aimed to evaluate the usefulness of serum leucin-rich alpha-2 glycoprotein (LRG) levels in monitoring disease...  相似文献   
64.
OBJECTIVE: The aim of the present study was to evaluate the influence of inhaled corticosteroids (ICS) on community-acquired pneumonia (CAP) in patients with asthma. PATIENTS AND METHODS: All asthmatic patients who required hospitalization for CAP from the beginning of 1989 through December 2001 were enrolled in this retrospective study. Patients who used oral corticosteroids daily were excluded. Patients were divided into two groups based on whether or not they used ICS, and we analyzed clinical characteristics of the pneumonia. Sixty-two patients (28 males, 34 females; mean age, 54.5 years) were enrolled in this study. Thirty-seven of 62 patients used ICS, with the mean dosage being 777.9 microg/day. RESULTS: We found no significant differences between the two groups with regard to mean age, serum albumin level, duration of asthma, pulmonary function and frequency of intravenous infusion of corticosteroids in the outpatient department. There were no significant differences in body temperature, white blood cell count, and CRP value upon admission between the two groups. Differences were not significant in the period of resolution of the pneumonia or in the frequency of pathogens identified between the two groups. CONCLUSION: ICS therapy appears to have no influence on CAP in patients with asthma. We recommend that ICS should be continued to control asthma with adequate antibiotic therapy when asthmatic patients have CAP.  相似文献   
65.
BACKGROUND AND AIM: The authors have previously shown that production of interleukin (IL)-18 was increased in the inflamed mucosa of patients with Crohn's disease (CD) and blockade of IL-18 ameliorated the murine model of CD. This demonstrated that IL-18 plays a significant role during intestinal inflammation. However, the initial role of IL-18 during intestinal inflammation was unclear; therefore the susceptibility of IL-18 transgenic (Tg) mice to acute dextran sulfate sodium (DSS)-induced colitis was examined. METHODS: Interleukin-18 Tg and wild-type (WT) mice were fed 2.0% of DSS for 8 days. The total clinical scores (bodyweight loss, stool consistency, and rectal bleeding), colon length and histological scores were assessed. The expressions of surface markers and IL-18 on infiltrating lamina propria mononuclear cells were analyzed immunohistochemistrically. Mesenteric lymph node (MLN) cells were isolated and the expressions of CD4+ T-cell activation markers (CD69, CD25 and IL18R) were analyzed by flow cytometry. RESULTS: The IL-18 Tg mice exhibited an increased susceptibility to DSS-induced colitis, as shown by significantly increased clinical, histological scores, and more severe colonic shortening compared with WT mice. Immunohistochemical analysis revealed a significant increase of IL-18 production and CD11b+ macrophages but not CD4+ T cells in the inflamed mucosa in DSS-fed IL-18 Tg compared with DSS-fed WT mice. Furthermore, MLN cells revealed no evidence of increased CD4+ T-cell activation in DSS-fed IL-18 Tg. CONCLUSIONS: These findings suggest that IL-18 overproduction in the mucosa plays an important role in the marked infiltration of macrophages and exacerbates colitis in IL-18 Tg mice.  相似文献   
66.
Inflammatory bowel diseases such as ulcerative colitis or Crohn's disease frequently cause epithelial damage in the intestine. In general, the intestinal epithelium is able to rapidly repair itself by the restitution, proliferation, and differentiation of epithelial cells when such tissue damage occurs. However, severe and continuous inflammation could disturb the intrinsic repair system, resulting in refractory ulcers in the intestine. In this review, we will describe the recent findings of the cellular and molecular mechanisms regulating the regeneration process of the intestinal epithelium. Furthermore, we will propose bone marrow cells as a novel source of cells to regenerate the damaged intestinal epithelium. Bone marrow cells are the only cells of extra-gastrointestinal origin that are shown to contribute to the regeneration of the intestinal epithelium. Further studies of these cells and molecules may lead to a novel therapy for the repair of damaged intestinal epithelium.  相似文献   
67.
NADH dehydrogenase subunit-2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism is associated with longevity in the Japanese population, and the ND2-237Met genotype may exert antiatherogenic effects. To investigate whether ND2-237 Leu/Met polymorphism is associated with risk of hypertension, we conducted a cross-sectional study of 398 Japanese male subjects. The frequency of hypertension was significantly higher in ND2-237Leu genotypic men than in ND2-237Met genotypic men. On analysis of covariance, the interaction between ND2-237 Leu/Met polymorphism and habitual drinking was significantly associated with both systolic blood pressure and diastolic blood pressure. Multiple logistic regression analysis revealed that the ND2-237Met genotype, particularly in younger subjects (age <60 years), had a lower odds ratio for hypertension than the ND2-237Leu genotype. Moreover, the association of ND2-237 Leu/Met polymorphism with hypertension may depend on the frequency of alcohol consumption. The odds ratio for hypertension was significantly higher in daily drinkers with ND2-237Leu when compared with non- or ex-drinkers with ND2-237Leu. However, the association between the ND2-237Met genotype and hypertension may not depend on the frequency of alcohol consumption. The present results suggest that ND2-237 Leu/Met polymorphism is associated with hypertension and that modification of hypertension risk is dependent on alcohol consumption in middle-aged Japanese men.  相似文献   
68.
Pregnant women are highly susceptible to malaria infection because of their low immunity and are at increased risk of maternal illness or death, in addition to spontaneous abortion, stillbirth, premature delivery, and low birth weight. However, the detailed pathogenesis of maternal malaria remains unclear. In this study, we evaluated a mouse model that shows similar severe pathological features of pregnant women during Plasmodium falciparum infection and investigated the pathogenesis of maternal malaria. Pregnant mice immunized by infection with an attenuated parasite, Plasmodium berghei XAT, were more susceptible to virulent P. berghei NK65 challenge/infection than were nonpregnant mice and showed high levels of parasitemia and a poor pregnancy outcome associated with placental pathology, such as accumulation of parasitized red blood cells, in the late phase of pregnancy. Notably, the pregnant immune mice challenged/infected with P. berghei NK65 developed liver injury associated with microvesicular fatty infiltration in late pregnancy. The pathological features were similar to acute fatty liver of pregnancy. Higher levels of gamma interferon and nitric oxide (NO) were found in plasma from pregnant immune mice infected with P. berghei NK65 than in plasma from nonpregnant mice. These findings suggest that development of liver injury and placental pathology in pregnant immune mice challenged/infected with P. berghei NK65 is accompanied by enhanced production of proinflammatory cytokines.  相似文献   
69.
Defects in the O-mannosyl glycan of α-dystroglycan (α-DG) are associated with α-dystroglycanopathy, a group of congenital muscular dystrophies. While α-DG has many O-mannosylation sites, only the specific positions can be modified with the functional O-mannosyl glycan, namely, core M3-type glycan. POMGNT2 is a glycosyltransferase which adds β1,4-linked GlcNAc to the O-mannose (Man) residue to acquire core M3-type glycan. Although it is assumed that POMGNT2 extends the specific O-Man residues around particular amino acid sequences, the details are not well understood. Here, we determined a series of crystal structures of POMGNT2 with and without the acceptor O-mannosyl peptides and identified the critical interactions between POMGNT2 and the acceptor peptide. POMGNT2 has an N-terminal catalytic domain and a C-terminal fibronectin type III (FnIII) domain and forms a dimer. The acceptor peptide is sandwiched between the two protomers. The catalytic domain of one protomer recognizes the O-mannosylation site (TPT motif), and the FnIII domain of the other protomer recognizes the C-terminal region of the peptide. Structure-based mutational studies confirmed that amino acid residues of the catalytic domain interacting with mannose or the TPT motif are essential for POMGNT2 enzymatic activity. In addition, the FnIII domain is also essential for the activity and it interacts with the peptide mainly by hydrophobic interaction. Our study provides the first atomic-resolution insights into specific acceptor recognition by the FnIII domain of POMGNT2. The catalytic mechanism of POMGNT2 is proposed based on the structure.  相似文献   
70.
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