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91.
In vitro antibacterial activity of antiseptics against vaginal lactobacilli   总被引:3,自引:0,他引:3  
The results of investigations carried out to evaluate the inhibitory activity in vitro of seven vaginal antiseptic douche solutions against several strains of vaginal lactobacilli isolated from asymptomatic women are reported. Some of the products examined showed marked antibacterial activity even at high dilutions and for short exposure times. The post-antibiotic effect of two of these antiseptics on vaginal lactobacilli was also evaluated. The results of these investigations suggest that uncontrolled use of antiseptic products could cause changes in the normal vaginal flora.  相似文献   
92.
Although research is beginning to clarify the relationship between structure and functional activity in the adult cerebral cortex, little is known about cortical development in the somatosensory cortex of cats. A number of parameters were used in this study to identify functional and anatomical correlates in the developing somatosensory cortex of kittens ranging in age from 3 to 33 d: 2-deoxyglucose (2DG) uptake, cytochrome oxidase (CO) activity, Nissl staining, and AChE activity. All of these parameters were found to reflect an immaturity that evolved to the adult-like pattern by 4-5 weeks of age. Nissl staining revealed an immature laminar pattern at birth, in which layers I, V, and VI were distinct whereas layers II-IV were homogeneous in appearance. Numerous cells could be observed at the layer VI-white matter junction and throughout the white matter, a feature not found in adults. The laminar distribution of Nissl-stained cells gradually became mature by 4-5 weeks of age. CO staining was homogeneous throughout all layers, in contrast to the adult pattern, which displays laminar differentiation. In young animals, many darkly stained CO+ cells were found at the layer VI-white matter border and in the white matter, a distribution not found in the adult. AChE staining in kittens was also distinctly different from that in adults. At birth, AChE+ fibers could be found in layers I, V, and VI but were scarce in layers II-IV. In the adult, a dense network of AChE+ fibers can be found in all layers. 2DG uptake was also immature, as little stimulus-evoked activity could be observed in animals younger than 2 weeks. A dense band of metabolic activity was found in the zone between layer VI and the white matter, whether or not a somatic stimulus was delivered. These results suggest a close correlation between the developing cytoarchitecture and the emergence of a mature pattern of functional activity in the somatosensory cortex.  相似文献   
93.
Myeloid cell lines were evaluated for the release of substances needed for colony formation by their own colony-forming cells (CFC) and by other myeloid cell lines. Dialyzed U937 conditioned medium (CM) had no effect on the cloning efficiency of U937 cells, whether or not U937 CFC had been induced for MHC class-II antigens by preincubation of these cells for 72 h with indomethacin and human gamma interferon (HuIFN gamma). Dialyzed U937 CM, however, restored colony formation of HuIFN gamma-induced U937 cells suppressed by lactoferrin (LF) or transferrin (TF). Dialyzed U937 CM did not restore colony formation of U937 cells suppressed by acidic isoferritins (AIF) or prostaglandin E2 (PGE2). Detection of the growth-restoring effects of U937 CM required that U937 CM be prepared in the presence of indomethacin or that the CM be dialyzed to remove inhibitors of U937 colony formation. Dialyzed U937 CM did not inactivate LF. Dialyzed U937 CM did not stimulate or enhance colony formation of normal human bone marrow granulocyte-macrophage (CFU-GM), erythroid (BFU-E), or multipotential (CFU-GEMM) progenitor cells, but did contain potent inhibitory activity against these progenitor cells. HL-60, EM2, EM3, and K562 cells were also evaluated. HL-60-, EM3-, and K562-CFC that were not preincubated with HuIFN gamma did not express MHC class-II antigens, and colony formation by these cells was not influenced by LF, TF, or AIF. Noninduced EM2-CFC constitutively expressed MHC class-II antigens, and colony formation by these cells was suppressed by LF, TF, and AIF. After induction of MHC class-II antigens on HL-60- and EM3-CFC by HuIFN gamma, colony formation by these cells was suppressed by LF, TF, and AIF. Colony formation by HuIFN gamma-induced EM2 cells was more responsive to inhibition by LF, TF, and AIF than was colony formation by noninduced EM2 cells. K562 cells were not induced into a responsive state to LF, TF, or AIF by HuIFN gamma. Dialyzed CM from HL-60, EM2, and EM3 cells contained activities that restored colony formation by their own LF-suppressed CFC. The activities present in dialyzed CM from U937, HL-60, EM2, and EM3 cells may be similar since they could each restore LF-suppressed colony formation of U937, HL-60, EM2, or EM3 cells.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
94.
95.
A case-control study design was used in order to compare the distribution of human cytomegalovirus (HCMV) glycoprotein B (gB) genotypes in 48 mothers of 49 congenitally infected infants with that observed in 144 mothers of 146 uninfected infants to study genetic variation of HCMV strains and maternal-fetal transmission. Congenital infection with HCMV was characterized by DNA detection and virus isolation from two urine or saliva samples collected prior to the third week of life. Genotyping of HCMV was carried out by a polymerase chain reaction-restriction fragment length polymorphism analysis of the variable region of the gB gene, testing for four genotypes. Genotype frequency was similar among the 28 non-transmitting mothers who were shedding virus (gB1: 25%; gB2: 28.6%; gB3: 42.8%; gB4: 0%), the 37 transmitting mothers (gB1: 21.6%; gB2: 46%; gB3: 27%; gB4: 0%), and the 49 infected infants (gB1: 39%; gB2: 37%; gB3: 24%; gB4: 0%). The same genotype was detected at different body sites (urine, saliva, and blood) of each infected newborn and in the respective mother (breast milk, urine, and saliva). Co-infection with multiple genotypes was observed in the immediate postpartum period in two mothers of infected infants (5.4%) and one non-transmitting mother (3.6%). The gB genotype was not correlated with intrauterine HCMV transmission. The genotype distribution found reflects the overall frequency of wild strains circulating in this geographic region. A single genotype is responsible for congenital HCMV infection. Co-infection with more than one strain, as characterized by gB genotype, was infrequent in women who were presumably immunocompetent.  相似文献   
96.
Vaccines with synthetic peptides induce the immune response to epitopes that bind to several HLA alleles. By using a TEPITOPE algorithm, we selected and analyzed the T-cell responses of peripheral blood mononuclear cells from 29 paracoccidioidomycosis (PCM) patients to peptides of the immunodominant gp43 antigen of Paracoccidioides brasiliensis, the causative agent of PCM.  相似文献   
97.
Recombinant Bacillus subtilis strains, either in the form of spores or vegetative cells, may be employed as safe and low-cost vaccine vehicles. In this study, we studied the role of promoter sequences and antigen-sorting signals on the immunogenicity based on previously constructed B. subtilis episomal expression systems. Mice orally immunized with spores or cells encoding the B subunit of the heat labile toxin (LTB), originally expressed by some enterotoxigenic Escherichia coli (ETEC) strains, under control of the stress-inducible gsiB promoter developed higher anti-LTB serum IgG and fecal IgA responses with regard to vaccine strains transformed with plasmids encoding the antigen under control of IPTG-inducible (Pspac) or constitutive (PlepA) promoters. Moreover, surface expression of the vaccine antigen under the control of the PgsiB promoter enhanced the immunogenicity of vegetative cells, while intracellular accumulation of LTB led to higher antibody responses in mice orally immunized with recombinant B. subtilis spores. Specific anti-LTB antibodies raised in vaccinated mice recognized and neutralized in vitro the native toxin produced by ETEC strains. Nonetheless, only mice orally immunized with recombinant B. subtilis strains, either as vegetative cells or spores, expressing intracellular LTB under the control of the gsiB promoter conferred partial protection to lethal challenges with purified LT. The present report further demonstrates that B. subtilis plasmid-based heterologous protein expression systems are adequate for antigen delivery via the oral route.  相似文献   
98.
99.

Background

Accurate temperature readings, often obtained rectally, are an important part of the initial evaluation of pediatric patients in the Emergency Department. Temporal artery thermometry (TAT) is one way to noninvasively measure temperature. We sought to compare the accuracy of axillary and temporal artery temperatures compared to rectal.

Methods

This prospective study included children age 0–36 months presenting to the Emergency Department of a large military treatment facility. Rectal, axillary, and temporal artery temperatures were obtained. Test characteristics (sensitivity, specificity, NPV, PPV) were reported. The effect of cutoff values 99.9 °F, 100.4 °F, and 102.2 °F on test characteristics were also evaluated.

Results

The sensitivities of axillary and temporal artery thermometry to detect rectal fever is 11.5% and 61.5% respectively. Cutoff values did not significantly alter test characteristics. In this study, temporal artery thermometry was 0.2 °C lower than rectal temperature, axillary measurement was 0.9 °C below the reference standard. Mean temperature difference in the febrile group between TAT and rectal thermometry was > 0.5 °C compared with a mean temperature difference 0.05 °C in afebrile patients.

Conclusion

The findings of our study do not support using axillary thermometry to screen pediatric patients for fever in the emergency department. TAT cannot be recommended as a rectal thermometry replacement where height and duration of fever are used in pediatric disease prediction models. TAT may have a role in screening for fever in the appropriate pediatric patient population like primary orthopedic or trauma presentations where the balance between device precision, data capture and patient comfort may favor use of TAT.  相似文献   
100.
Background: Patients with diabetes mellitus who undergo coronary stenting are at increased risk of restenosis. It is known that inflammation plays a crucial role in restenosis. Objective: We assessed the inflammatory response to elective coronary stent implantation (CSI) in stable diabetic and nondiabetic patients. Methods: C‐reactive protein (CRP), soluble (s) P‐selectin, and soluble intercellular adhesion molecule (sICAM)‐1 plasma levels were determined in diabetic (n = 51) and nondiabetic (n = 56) patients before and 48 hours and 4 weeks after bare metal stenting (BMS). Results: Diabetic patients presented significantly higher inflammatory marker levels before and after CSI. Nonetheless, diabetic and nondiabetic patients had postintervention peak of markers attained within 48 hours. At baseline, diabetic and nondiabetic patients presented CRP levels of 5.0 ± 20.1 (P ≤ 0.04) and 3.8 ± 9.4 μg/ml and, at 48 hours postintervention, 22.0 ± 20.2 (P = 0.001; P = 0.002) and 12.6 ± 11.3 (P ≤ 0.0001) μg/ml. Regarding sP‐selectin, diabetic and nondiabetic patients obtained levels of, at baseline, 182 ± 118 (P ≤ 0.04) and 105 ± 48 ng/ml and, at 48 hours, 455 ± 290 (P = 0.001; P ≤ 0.01) and 215 ± 120 (P ≤ 0.04) ng/ml. For diabetic and nondiabetic patients, sICAM‐1 levels were, at baseline, 248 ± 98 (P ≤ 0.04) and 199 ± 94 ng/ml and, at 48 hours, 601 ± 201 (P = 0.001; P ≤ 0.01) and 283 ± 220 (P = 0.001) ng/ml. At 4 weeks, for all patients, markers returned to preprocedural levels: versus before PCI: *P = 0.001, §P ≤ 0.0001; versus nondiabetic patients: #P ≤ 0.04, P = 0.002, ?P ≤ 0.01. Conclusions: Diabetic and nondiabetic patients exhibited a temporal inflammatory response after an elective BMS. However, diabetic patients present higher preprocedural levels of CRP, sP‐selectin, and sICAM‐1 and reveal a further exacerbated inflammatory response after intervention. The differences in inflammatory response may have implications in restenosis within these two sets of patients.  相似文献   
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