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121.

Background

Since 2007, Guatemala integrated STI clinical service with an HIV prevention model into four existing public health clinics to prevent HIV infection, known as the VICITS strategy. We present the first assessment of VICITS scale-up, retention, HIV and STI prevalence trends, and risk factors associated with HIV infection among Female Sex Workers (FSW) attending VICITS clinics in Guatemala.

Methods

Demographic, behavioral and clinical data were collected using a standardized form. Data was analyzed by year and health center. HIV and STI prevalence were estimated from routine visits. Retention was estimated as the percent of new users attending VICITS clinics who returned for at least one follow-up visit to any VICITS clinic within 12 months. Separate multivariate logistic regression models were conducted to investigate factors associated with HIV infection and program retention.

Results

During 2007–2011 5,682 FSW visited a VICITS clinic for the first-time. HIV prevalence varied from 0.4% to 5.8%, and chlamydia prevalence from 0% to 14.3%, across sites. Attending the Puerto Barrios clinic, having a current syphilis infection, working primarily on the street, and using the telephone or internet to contact clients were associated with HIV infection. The number of FSW accessing VICITS annually increased from 556 to 2,557 (361%) during the period. In 2011 retention varied across locations from 7.7% to 42.7%. Factors negatively impacting retention included current HIV diagnosis, having practiced sex work in another country, being born in Honduras, and attending Marco Antonio Foundation or Quetzaltenango clinic sites. Systematic time trends did not emerge, however 2008 and 2010 were characterized by reduced retention.

Conclusions

Our data show local differences in HIV prevalence and clinic attendance that can be used to prioritize prevention activities targeting FSW in Guatemala. VICITS achieved rapid scale-up; however, a better understanding of the causes of low return rates is urgently needed.  相似文献   
122.
Curcumin, a dietary polyphenol, has shown a potential to act on the symptoms of neurodegenerative disorders, including Alzheimer’s and Parkinson’s diseases, as a consequence of its antioxidant, anti-inflammatory and anti-protein aggregation properties. Unfortunately, curcumin undergoes rapid degradation at physiological pH into ferulic acid, vanillin and dehydrozingerone, making it an unlikely drug candidate. Here, we evaluated the ability of some curcumin by-products: dehydrozingerone (1), its O-methyl derivative (2), zingerone (3), and their biphenyl analogues (4–6) to interact with α-synuclein (AS), using CD and fluorescence spectroscopy. In addition, the antioxidant properties and the cytoprotective effects in rat pheochromocytoma (PC12) cells prior to intoxication with H2O2, MPP+ and MnCl2 were examined while the Congo red assay was used to evaluate the ability of these compounds to prevent aggregation of AS. We found that the biphenyl zingerone analogue (6) interacts with high affinity with AS and also displays the best antioxidant properties while the biphenyl analogues of dehydrozingerone (4) and of O-methyl-dehydrozingerone (5) are able to partially inhibit the aggregation process of AS, suggesting the potential role of a hydroxylated biphenyl scaffold in the design of AS aggregation inhibitors.  相似文献   
123.
Silene marizii (Caryophyllaceae) is a schizoendemism of the west Iberian Peninsula. The correlation between the evolution of reproductive success (as measured in terms of fruit set and seed production) and five floral traits (peduncle length, calyx length, calyx width, petal limb length, and petal limb width) was investigated in five populations of S. marizii, taking into account both intra-populational and inter-populational variability. The populations studied represented the different habitats of S. marizii over its area of distribution. None of the five traits examined was significantly and positively correlated with the number of seeds produced by the flower. An analysis was also made of how floral morphology varies with the position of the flower in the inflorescence in the five populations. The populations from higher altitudes (Caramulhino, Puerto de Menga and Peña de la Cruz) had larger peduncles, calices and petal limbs than those living at lower altitudes (Sabugal and Mangualde) All five morphometric traits, plus the number of ovules per ovary, varied significantly between flower positions on the same plant and among populations.  相似文献   
124.
Activation of the γ-class carbonic anhydrase (CAs, EC 4.2.1.1) from the pathogenic bacterium Burkholderia pseudomallei (BpsγCA) with a series of natural and non-natural amino acids and aromatic/heterocyclic amines has been investigated. The best BpsγCA activators were d-His, l-DOPA, d-Trp, 4-amino-l-Phe, dopamine, 2-(2-aminoethyl)pyridine, 2-aminoethyl-piparazine/morpholine and l-adrenaline, which showed activation constants ranging between 9 and 86 nM. The least effective activators were l-His, l-Phe and 2-pyridyl-methylamine, with KAs in the range of 1.73–24.7 μM. As little is known about the role of γ-CAs in the lifecycle and virulence of this saprophytic bacterium, this study may shed some light on such phenomena. This is the first CA activation study of a γ-CA from a pathogenic bacterium, the only other such study being on the enzyme discovered in the archaeon Methanosarcina thermophila, Cam.  相似文献   
125.
HER-2/neu is an immunogenic protein eliciting both humoral and cellular immune responses in patients with HER-2/neu-positive (+) tumors. Preexisting cytotoxic T lymphocyte (CTL) immunity to HER-2/neu has so far been mainly evaluated in terms of detection of CTL precursor (CTLp) frequencies to the immunogenic HLA-A2–binding nona-peptide 369-377 (HER-2(9369)). In the present study, we examined patients with HER-2/neu+ breast, ovarian, lung, colorectal, and prostate cancers for preexisting CTL immunity to four recently described HER-2/neu–derived and HLA-A2–restricted "cytotoxic" peptides and to a novel one spanning amino acids 777–785 also with HLA-A2–binding motif. We utilized enzyme-linked immunosorbent spot (ELISpot) assay, which allows a quantitative and functional assessment of T cells directed against specific peptides after only brief in vitro incubation. CTL reactivity was determined with an interferon (IFN-) ELISpot assay detecting T cells at the single cell level secreting IFN-. CTLp were defined as peptide-specific precursors per 106 peripheral blood mononuclear cells (PBMCs). Patients' PBMCs with increased CTLp were also tested against autologous tumor targets and peptide-pulsed dendritic cells (DCs) in cytotoxicity assays. We also studied patients with HER-2/neu-negative (-) tumors and healthy individuals. Of the HER-2/neu+ patients examined, 31% had increased CTLp to HER-2(9952), 19% to HER-2(9665), 16% to HER-2(9689), and 12.5% HER-2(9435), whereas only 2 of 32 patients (6%) responded to HER-2(9777). The CTLp recognizing HER-2(9952) were extremely high in two patients with breast cancer, one with lung cancer, and one with prostate cancer. None of the HER-2/neu- patients or healthy donors exhibited increased CTLp to any of these peptides. Besides IFN- production, preexisting CTL immunity to all five HER-2/neu peptides was also shown in cytotoxicity assays where patients' PBMCs with increased CTLp specifically lysed autologous tumor targets and autologous peptide-pulsed DCs. Our results demonstrate for the first time that (1) preexisting immunity to peptides HER-2(9435), HER-2(9952), HER-2(9689), HER-2(9665), and HER-2(9777) is present in patients with HER-2/neu+ tumors of distinct histology, (2) HER-2(9777) is a naturally processed peptide expressed on the surface of HER-2/neu+ tumors, as are the other four peptides, and (3) HER-2/neu+ prostate tumor cells can be recognized and lysed by autologous HER-2 peptide-specific CTL. Our findings broaden the potential application of HER-2/neu-based immunotherapy.  相似文献   
126.
Yeast piD261/Bud32 and its homologues are present in eukaryotes and in archaea but not in bacteria and are believed to make up a primordial branch of the eukaryotic protein kinase superfamily. Here, we show that, at variance with the majority of Ser/Thr protein kinases which recognize phosphoacceptor sites specified by basic and/or proline residues, piD261 phosphorylates in vitro a number of acidic proteins and peptides, and it recognizes seryl residues specified by carboxylic side chains. These data suggest that recognition of acidic sites might have been a primordial trait of protein kinases, which was modified during evolution to cope with the increasing complexity of protein phosphorylation in eukaryotes.  相似文献   
127.
Acquisition of sperm fertilizing ability is due, in part, to the reorganization of plasma membrane proteins that occurs during epididymal sperm transit. Using polyclonal antibodies against angiotensin I-converting enzyme (ACE), we showed that this enzyme is immunolocalized mainly on the middle piece of rat and mouse testicular sperm and with less intensity along the initial part of the principal piece of the flagellum. In both species, only some sperm from the caput epididymis were still reactive, whereas no labeling was observed on cauda epididymal sperm. The 105- to 110-kDa germinal ACE was absent from the rat testicular fluid but appeared in the fluid of the anterior epididymis. Thereafter, its molecular weight shifted to 94 kDa in the corpus epididymal fluid and remained at this weight in the caudal region. The 105- to 110-kDa immunoreactive protein was present in testicular rat sperm extract but was completely absent from epididymal sperm extracts. Western blot analysis of testicular and epididymal tissue extracts from the rat and mouse also confirmed that the germinal enzyme was absent from the epididymal sperm cell. Our results demonstrated that the rodent germinal ACE is released from the testicular sperm membrane when sperm enter the epididymis, a process similar to that observed in domestic mammals. This result is discussed in view of the suggested role for this enzyme in sperm fertility.  相似文献   
128.
Inflammatory disorders of the central nervous system such as multiple sclerosis and acute disseminated encephalomyelitis involve an invasion of immune cells that ultimately leads to white matter demyelination, neurodegeneration and development of neurological symptoms. A clinical diagnosis is often made when neurodegenerative processes are already ongoing. In an attempt to seek early indicators of disease, we studied the temporal and spatial distribution of brain modifications in experimental autoimmune encephalomyelitis (EAE). In a thorough magnetic resonance imaging study performed with EAE mice, we observed significant enlargement of the ventricles prior to disease clinical manifestation and an increase in free water content within the cerebrospinal fluid as demonstrated by changes in T2 relaxation times. The increase in ventricle size was seen in the lateral, third and fourth ventricles. In some EAE mice the ventricle size started returning to normal values during disease remission. In parallel to this macroscopic phenomenon, we studied the temporal evolution of microscopic lesions commonly observed in the cerebellum also starting prior to disease onset. Our data suggest that changes in ventricle size during the early stages of brain inflammation could be an early indicator of the events preceding neurological disease and warrant further exploration in preclinical and clinical studies.  相似文献   
129.

Background

Recent development in the field of COPD has focused on strategies aimed at reducing the underlying inflammation through selective inhibition of the phosphodiesterase type IV (PDE4) isoform. Although the anti-inflammatory and bronchodilator activity of selective PDE4 inhibitors has been well documented, their low therapeutic ratio and dose-dependent systemic side effects have limited their clinical utility. This study examined the effect of 2''-deoxy-2''-Fluoro-β-D-Arabinonucleic Acid (FANA)-containing antisense oligonucleotides (AON) targeting the mRNA for the PDE4B/4D and 7A subtypes on lung inflammatory markers, both in vitro and in vivo.

Methods

Normal human bronchial epithelial (NHBE) cells were transfected with FANA AON against PDE4B/4D and 7A alone or in combination. mRNA levels for target PDE subtypes, as well as secretion of pro-inflammatory chemokines were then measured following cell stimulation. Mice were treated with combined PDE4B/4D and 7A AON via endo-tracheal delivery, or with roflumilast via oral delivery, and exposed to cigarette smoke for one week. Target mRNA inhibition, as well as influx of inflammatory cells and mediators were measured in lung lavages. A two-week smoke exposure protocol was also used to test the longer term potency of PDE4B/4D and 7A AONs.

Results

In NHBE cells, PDE4B/4D and 7A AONs dose-dependently and specifically inhibited expression of their respective target mRNA. When used in combination, PDE4B/4D and 7A AONs significantly abrogated the cytokine-induced secretion of IL-8 and MCP-1 to near baseline levels. In mice treated with combined PDE4B/4D and 7A AONs and exposed to cigarette smoke, significant protection against the smoke-induced recruitment of neutrophils and production of KC and pro-MMP-9 was obtained, which was correlated with inhibition of target mRNA in cells from lung lavages. In this model, PDE AONs exerted more potent and broader anti-inflammatory effects against smoke-induced lung inflammation than roflumilast. Moreover, the protective effect of PDE4B/4D and 7A AON was maintained when a once-weekly treatment schedule was used.

Conclusion

These results indicate that inhaled AON against PDE4B/4D and 7A have unique effects on biomarkers that are believed to be important in the pathophysiology of COPD, which supports further development as a potential therapy in this disease.  相似文献   
130.
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