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101.
We describe the development of a human bone marrow (BM) culture system which allows study of the interaction of stromal cell lines (SCL) and highly purified hematopoietic progenitor cells. Normal BM stromal cells were electroporated with a plasmid containing the simian virus 40 (SV40) large T antigen (SV40 T Ag) under the control of a synthetic metallothionein promoter (MT4); this construct is designated MT4 SV40 T Ag. SCL in which the rate of proliferation could be controlled by altering the zinc (Zn) concentration were characterized, demonstrating that the SCL were heterogeneous with respect to G-CSF and GM-CSF production. Suppression of SCL proliferation on removal of Zn made it possible to use these lines in coculture with purified CD34+ progenitor cells from umbilical cord blood. The ability to control proliferation of SCL has allowed us to maintain the survival and expansion of colony- forming cells in culture for up to 2 months. These lines have enabled us to test for stromal cell characteristics at a clonal level and provided us with a tool to analyze the events leading to lineage commitment and hematopoietic differentiation, as demonstrated by suppression of hematopoiesis by an antibody directed against the c-kit molecule.  相似文献   
102.
Synapsin I is a synaptic vesicle-associated phosphoprotein that has been implicated in the formation of presynaptic specializations and in the regulation of neurotransmitter release. The nonreceptor tyrosine kinase c-Src is enriched on synaptic vesicles, where it accounts for most of the vesicle-associated tyrosine kinase activity. Using overlay, affinity chromatography, and coprecipitation assays, we have now shown that synapsin I is the major binding protein for the Src homology 3 (SH3) domain of c-Src in highly purified synaptic vesicle preparations. The interaction was mediated by the proline-rich domain D of synapsin I and was not significantly affected by stoichiometric phosphorylation of synapsin I at any of the known regulatory sites. The interaction of purified c-Src and synapsin I resulted in a severalfold stimulation of tyrosine kinase activity and was antagonized by the purified c-Src-SH3 domain. Depletion of synapsin I from purified synaptic vesicles resulted in a decrease of endogenous tyrosine kinase activity. Portions of the total cellular pools of synapsin I and Src were coprecipitated from detergent extracts of rat brain synaptosomal fractions using antibodies to either protein species. The interaction between synapsin I and c-Src, as well as the synapsin I-induced stimulation of tyrosine kinase activity, may be physiologically important in signal transduction and in the modulation of the function of axon terminals, both during synaptogenesis and at mature synapses.  相似文献   
103.
Household food insecurity (HHFI) may be a barrier to both optimal maternal nutritional status and infant feeding practices, but few studies have tested this relationship quantitatively, and never among HIV-infected individuals. We therefore described the prevalence of HHFI and explored if it was associated with poorer maternal nutritional status, shorter duration of exclusive breastfeeding (EBF) and fewer animal-source complementary foods. We assessed these outcomes using bivariate and multivariate analyses among 178 HIV-infected pregnant and breastfeeding (BF) women receiving combination antiretroviral therapy in the PROMOTE trial (NCT00993031), a prospective, longitudinal cohort study in Tororo, Uganda. HHFI was common; the prevalence of severe, moderate, and little to no household hunger was 7.3, 39.9, and 52.8 %, respectively. Poor maternal nutritional status was common and women in households experiencing moderate to severe household hunger (MSHH) had statistically significantly lower body mass index (BMIs) at enrollment (21.3 vs. 22.5, p < 0.01) and prior to delivery (22.6 vs. 23.8, p < 0.01). BMI across time during pregnancy, but not gestational weight gain, was significantly lower for MSHH [adjusted beta (95 % CI) ?0.79 (?1.56, ?0.02), p = 0.04; ?2.06 (?4.31, 0.19), p = 0.07], respectively. The prevalence (95 % CI) of EBF at 6 months was 67.2 % (59.7–73.5 %), and the proportion of women BF at 12 months was 80.4 % (73.3–85.7 %). MSHH was not associated with prevalence of EBF at 6 months or BF at 12 months. However, among those women still EBF at 4 months (81.4 % of population), those experiencing MSHH were significantly more likely to cease EBF between 4 and 6 months (aHR 2.38, 95 % CI 1.02–5.58). The prevalence of HHFI, maternal malnutrition, and suboptimal infant feeding practices are high and the causal relationships among these phenomena must be further explored.  相似文献   
104.
Notwithstanding fundamental methodological advancements, scientific information about disorders of consciousness (DOCs)—e.g. Vegetative State/Unresponsive Wakefulness Syndrome (VS/UWS) and Minimally Conscious State (MCS)—is incomplete. The possibility to discriminate between different levels of consciousness in DOC states entails treatment strategies and ethical concerns. Here we attempted to investigate Italian clinicians’ and basic scientists’ opinions regarding some issues emerging from the care and the research on patients with DOCs. From our survey emerged that Italian physicians working with patients with DOCs give a central role to ethics. Current Italian regulation regarding basic research conducted in patients with DOCs apparently risks to be inadequate to support scientific advancement, and would deserve a different assessment compared to ordinary treatments. We think the results of our survey deserve attention from an international audience because they exemplify the difficulty to define a shared approach to the issues related to patients with DOCs and the necessity to better assess both the ordinary and experimental treatment of patients with DOCs at the ethical and legal level.  相似文献   
105.

Background

The first reliable statistic data about perioperatory mortality were published in 1841 by the French Joseph-Francois Malgaigne (1806–1863): he referred to a mean mortality of 60% for amputations and this bad result was to be attributed mainly to hospital acquired diseases. The idea of “hospital acquired disease” although vague, included five infective nosologic entities, which at that time were diagnosed more frequently: erysipelas, tetan, pyemia, septicemia, and gangrene. Nonetheless, the suppuration with pus production was considered from most of the surgeons and doctors of that time as a necessary and unavoidable step in the process of wound healing. During the end of the eighteenth century, hospitals of the main European cities were transforming into aggregations of several wards, where the high concentration of patients created poor sanitary conditions and a consistent increase of perioperatory mortality. In 1865, Lister applied his first antiseptic dressing on the surface of an exposed fracture. These experimental attempts lead to an effective reduction of wound infections respect to the dressing with strings used previously.

Discussion

Lister's innovations in the field of wound treatment were based on two brand new concepts: germs causing rot were ubiquitarious and the wound infection was not a normal step in the process of wound healing. The concept of antisepsis was hardly accepted in the European surgical world: “Of all countries, Italy is the most indifferent and uninterested in experimenting this method, which has been so favorably judged from the greatest surgical societies in Germany”. This quotation from the young surgeon Giuseppe Ruggi (1844–1925) from Bologna comes from his article where he presented his first experiences on aseptic medications started the previous year in the Surgical Department of Maggiore Hospital in Bologna. In his report, Ruggi described the adopted technique and suggested that the medication should be extended to all the surgical patients of the hospital:“… this is needed to totally remove from the hospital all those elements of infection which grow in the wounds dressed with the old method”. The experimentation of this new dressing for the few treated cases was rigorous and concerned both the sterilization of surgical tools with the fenic acid (5%) and the shaving of the skin. Ruggi also observed that there was no correlation between the seriousness of the wound and its extension or way of healing: when “simple” cases that “should heal without complication” showed fever he often realized that “it was often due to a medication performed without following the rules for an accurate disinfection and dressing”. Ruggi thought that the fever was connected to “reabsorption of pyrogenic substances, which can be removed cleaning and disinfecting the wound” in cases of wounds not accurately dressed and rarely medicated. Frequent postoperative medications of the wound were able to eliminate the fever within 2 h. Ruggi's attitude toward the fine reasoning lead him to introduce the concept of immunodeficiency related to physical deterioration: “… patients treated for surgical disease may sometimes suffer from complications of medical conditions, which initially escape the most accurate investigations… The surgical operation could, in some cases, hold the balance of power”.

Conclusions

The obtained results, published in 1879, appear extremely interesting. As he wrote in 1898, for the presentation of his case record of more than 1000 laparotomies, he had started “… operating as a young surgeon without any tutor, helped only by his mind and what he could deduce from publications existing at the moment …”.  相似文献   
106.
The treatment of premenstrual dysphoric disorder (PMDD) is far from satisfactory, as there is a high proportion of patients who do not respond to conventional treatment. The antidiuretic sulfonamide, acetazolamide, inhibits carbonic anhydrase and potentiates GABAergic transmission; the latter is putatively involved in PMDD. We therefore tried acetazolamide in a series of women with intractable PMDD. Here, we describe a series of eight women diagnosed with DSM-IV-TR PMDD, five of whom had comorbidity with a mood disorder and one with an anxiety disorder, who were resistant to treatment and responded with symptom disappearance after being added-on 125 mg/day acetazolamide for 7-10 days prior to menses each month. Patients were free from premenstrual symptoms at the 12-month follow-up. We suggest that acetazolamide may be used to improve symptoms of PMDD in cases not responding to other treatments. GABAergic mechanisms may be involved in counteracting PMDD symptoms.  相似文献   
107.

Background

Pulmonary arterial hypertension (PAH) is a disease that results in right ventricular (RV) dysfunction. While pulmonary vascular disease is the primary pathological focus, RV hypertrophy and RV dysfunction are the major determinants of prognosis in PAH. The aim of this study was to investigate the effects of (E)-N′-(3,4-dimethoxybenzylidene)-4-methoxybenzohydrazide (LASSBio-1386), an N-acylhydrazone derivative, on the lung vasculature and RV dysfunction induced by experimental PAH.

Methods

Male Wistar rats were injected with a single dose (60 mg/kg, i.p.) of monocrotaline (MCT) and given LASSBio-1386 (50 mg/kg, p.o.) or vehicle for 14 days. The hemodynamic, exercise capacity (EC), endothelial nitric oxide synthase (eNOS), adenosine A2A receptor (A2AR), sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA2a), phospholamban (PLB) expression, Ca2 +-ATPase activity and vascular activity of LASSBio-1386 were evaluated.

Results and conclusions

The RV systolic pressure was elevated in the PAH model and reduced from 49.6 ± 5.0 mm Hg (MCT group) to 27.2 ± 2.1 mm Hg (MCT + LASSBio-1386 group; P < 0.05). MCT administration also impaired the EC, increased the RV and pulmonary arteriole size, and promoted endothelial dysfunction of the pulmonary artery rings. In the PAH group, the eNOS, A2AR, SERCA2a, and PLB levels were changed compared with the control; in addition, the Ca2 +-ATPase activity was reduced. These alterations were related with MCT-injected rats, and LASSBio-1386 had favorable effects that prevented the development of PAH. LASSBio-1386 is effective at preventing endothelial and RV dysfunction in PAH, a finding that may have important implications for ongoing clinical evaluation of A2AR agonists for the treatment of PAH.  相似文献   
108.
Perception of microbe-associated molecular patterns (MAMPs) through pattern recognition receptors (PRRs) triggers various defense responses in plants. This MAMP-triggered immunity plays a major role in the plant resistance against various pathogens. To clarify the molecular basis of the specific recognition of chitin oligosaccharides by the rice PRR, CEBiP (chitin-elicitor binding protein), as well as the formation and activation of the receptor complex, biochemical, NMR spectroscopic, and computational studies were performed. Deletion and domain-swapping experiments showed that the central lysine motif in the ectodomain of CEBiP is essential for the binding of chitin oligosaccharides. Epitope mapping by NMR spectroscopy indicated the preferential binding of longer-chain chitin oligosaccharides, such as heptamer-octamer, to CEBiP, and also the importance of N-acetyl groups for the binding. Molecular modeling/docking studies clarified the molecular interaction between CEBiP and chitin oligosaccharides and indicated the importance of Ile122 in the central lysine motif region for ligand binding, a notion supported by site-directed mutagenesis. Based on these results, it was indicated that two CEBiP molecules simultaneously bind to one chitin oligosaccharide from the opposite side, resulting in the dimerization of CEBiP. The model was further supported by the observations that the addition of (GlcNAc)8 induced dimerization of the ectodomain of CEBiP in vitro, and the dimerization and (GlcNAc)8-induced reactive oxygen generation were also inhibited by a unique oligosaccharide, (GlcNβ1,4GlcNAc)4, which is supposed to have N-acetyl groups only on one side of the molecule. Based on these observations, we proposed a hypothetical model for the ligand-induced activation of a receptor complex, involving both CEBiP and Oryza sativa chitin-elicitor receptor kinase-1.Plants have the ability to detect potential pathogens through the recognition of microbe-associated molecular patterns (MAMPs; also known as pathogen-associated molecular patterns), such as flagellin, elongation factor Tu (EF-Tu), peptidoglycan, LPS, chitin, and β-glucan, which are typical molecular signatures for whole classes of microbes (1, 2). MAMP-triggered defense is the first barrier to prevent the invasion of pathogens and plays a major role in the basal resistance of plants against various pathogens. It is also well known that this defense system is strikingly similar to the innate immunity of animals (1, 3, 4).Leucine-rich repeat receptor-like kinases, flagellin-sensetive 2 (FLS2), and EF-Tu receptor, have been shown to recognize bacterial flagellin and EF-Tu, respectively, and serve as receptors for these MAMPs (5). On the other hand, two types of lysin motif (LysM) proteins, CEBiP (chitin-elicitor binding protein) and CERK1 (chitin-elicitor receptor kinase-1), were identified as the cell-surface receptor for chitin, a representative fungal molecular pattern (68). Knockout/-down experiments of these genes showed that both of these LysM proteins are required for chitin perception and signaling in rice, whereas CEBiP-type molecules are not involved in chitin signaling in Arabidopsis, indicating the difference between the chitin receptor systems in these model plants (8). Additionally, another LysM receptor-like kinase, LYK4, was also indicated to contribute to chitin signaling in Arabidopsis (9). In the case of rice, it was also shown that CEBiP and Oryza sativa (Os)CERK1 form a heterooligomeric receptor complex ligand dependently (10).Both CEBiP and OsCERK1 have LysMs, which have been known to bind peptidoglycan and chitin (11), in their ectodomains. In Arabidopsis, CERK1 was shown to bind chitin and trigger immune responses as a kind of “all-in-one” receptor. On the other hand, CEBiP seems to play a major role in the perception of chitin in rice, as the knockdown of CEBiP almost abolished the binding of a radio-labeled chitin oligosaccharide to the plasma membrane, whereas OsCERK1 was shown not to bind chitin (6, 12). Liu et al. recently reported that two other CEBiP homologs, OsLYP4 and -6, also bind chitin and contribute to chitin responses and disease resistance in rice (13), although it is not clear to what extent these proteins contribute as the cell surface receptor for chitin oligosaccharides.It was also shown that the perception of peptidoglycan in Arabidopsis requires CEBiP-like molecules (14). Arabidopsis homologs of CEBiP, LYM1 and LYM3, play a major role for the binding of peptidoglycan and activation of downstream defense responses through the receptor kinase, CERK1. These results showed that the receptor kinase CERK1 is required for both chitin and peptidoglycan signaling, at least in Arabidopsis. The peptidoglycan receptor system in Arabidopsis seems similar to the rice chitin receptor for the requirement of a binding protein and a receptor kinase, although the receptor complex formation by these two proteins was not confirmed.Thus, the detailed analysis of ligand recognition by these CEBiP-like molecules and succeeding formation and activation of receptor complex is critically important to understand the molecular mechanisms leading to the activation of downstream defense responses triggered by these MAMPs. Such information would also contribute to the design of novel receptor molecules suitable for future biotechnological application. We show herein the results obtained by biochemical studies on the binding site of CEBiP, epitope mapping of chitin oligosaccharides by saturation transfer difference (STD) NMR spectroscopy, and molecular modeling/docking studies combined with site-directed mutagenesis of the ectodomain of CEBiP. These results clearly indicated that two CEBiP molecules simultaneously bind to one N-acetylchitoheptaose/octaose, (GlcNAc)7/8, through a binding site located in the central LysM region of the ectodomain, resulting in the dimerization of CEBiP. Based on these observations, we proposed a hypothetical model for the ligand-induced activation of a receptor complex, involving both CEBiP and OsCERK1.  相似文献   
109.

Aims

Osteoprotegerin (OPG) is a secretory glycoprotein that belongs to the tumor necrosis factor receptor family and plays a role in atherosclerosis. OPG has been hypothesized to modulate vascular functions; however, its role in mediating atherosclerosis is controversial. Epidemiological data in patients with cardiovascular disease (CVD) indicate that OPG serum levels are associated with several inflammatory markers, myocardial infarction events, and calcium scores, suggesting that OPG may be causative for CVD.

Methods

The present study aimed to evaluate whether the OPG gene (TNFRSF11B) polymorphisms are involved in the development of peripheral arterial occlusive disease (PAOD) and critical limb ischemia (CLI) in patients with type 2 diabetes. This genetic association study included 402 diabetic patients (139 males and 263 females) with peripheral arterial occlusive disease and 567 diabetic subjects without peripheral arterial occlusive disease (208 males and 359 females). The T245G, T950C, and G1181C polymorphisms of the OPG gene were analyzed by polymerase chain reaction and restriction fragment length polymorphism.

Results

We found that the T245G, T950C, and G1181C gene polymorphisms of the OPG gene were significantly (27.9 vs. 12.2 %, P < 0.01; 33.6 vs. 10.4 %, P < 0.01 and 24.4 vs. 12.7 %, P < 0.01, respectively) and independently (adjusted OR 4.97 (3.12–6.91), OR 7.02 (4.96–11.67), and OR 2.85 (1.95–4.02), respectively) associated with PAOD. We also found that these three polymorphisms act synergistically in patients with PAOD and are associated with different levels of risk for PAOD and CLI, depending on the number of high-risk genotypes carried concomitantly by a given individual.

Conclusion

The TNFRSF11B gene polymorphisms under study are associated with PAOD, and synergistic effects between these genotypes might be potential markers for the presence and severity of atherosclerotic disorders.  相似文献   
110.

Background

The TNM Classification of Malignant Tumours (TNM) staging system is the primary means of determining a prognosis for gastric adenocarcinoma (GC). However, tumor behavior in the individual patient is unpredictable and in spite of treatment advances, a classification of 'advanced stage' still portends a poor prognosis. Thus, further insights from molecular analyses are needed for better prognostic stratification and determination of new therapeutic targets.

Methods

A total of fifty-one fresh frozen tumor samples from patients with histopathologically confirmed diagnoses of GC, submitted to surgery with curative intent, were included in the study. Total RNA was extracted from an initial group of fifteen samples matched for known prognostic factors, categorized into two subgroups, according to patient overall survival: poor (<24 months) or favorable (at or above 24 months), and hybridized to Affymetrix Genechip human genome U133 plus 2.0 for genes associated with prognosis selection. Thirteen genes were selected for qPCR validation using those initial fifteen samples plus additional thirty-six samples.

Results

A total of 108 genes were associated with poor prognosis, independent of tumor staging. Using systems biology, we suggest that this panel reflects the dampening of immune/inflammatory response in the tumor microenvironment level and a shift to Th2/M2 activity. A gene trio (OLR1, CXCL11 and ADAMDEC1) was identified as an independent marker of prognosis, being the last two markers validated in an independent patient cohort.

Conclusions

We determined a panel of three genes with prognostic value in gastric cancer, which should be further investigated. A gene expression profile suggestive of a dysfunctional inflammatory response was associated with unfavorable prognosis.  相似文献   
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