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81.
Cutaneous wound pain causes physical and psychological stress for patients with wounds. Previous studies reported that stress induces hyperalgesia and deteriorates wound healing. However, the effect of the stress response such as in hypothalamic‐pituitary‐adrenal (HPA) axis on local wound area is unclear. We aimed to investigate the effects of a stress response on the mechanical withdrawal threshold in the local wound area and describe the identification of a wound pain exacerbation. We topically injected adrenocorticotropic hormone (ACTH) into the granulation tissue of full‐thickness cutaneous wound model rats on the fifth day postwounding and measured the mechanical withdrawal thresholds, cytochrome P450 2Bs levels and concentration of 5,6‐epoxyeicosatrienoic acid in wound exudate. We found that ACTH induced mechanical hypersensitivity at 4 and 6 hours after injection (P = .004 and .021, respectively), and increased gene expression of cytochrome P450 2B12 expression (P = .046). Concentration of 5,6‐EET in the wound exudate was moderately correlated with the mechanical withdrawal threshold (r = ?.630). Finally, the mechanical withdrawal threshold in the 5,6‐EET group was significantly lower than that in the control group at 2 hours after the injection (P = .015). We propose that 5,6‐EET is one of the most promising contributors to the wound pain exacerbation. These findings could guide clinical wound and pain management.  相似文献   
82.
83.
Prader–Willi syndrome and Angelman syndrome are associated with parent-of-origin-specific abnormalities of chromosome 15q11–q13, most frequently a deletion of an ~4-Mb region. Because of genomic imprinting, paternal deficiency of this region leads to PWS and maternal deficiency to AS. Additionally, this region is frequently involved in other chromosomal rearrangements including duplications, triplications, or supernumerary marker formation. A detailed physical map of this region is important for elucidating the genes and mechanisms involved in genomic imprinting, as well as for understanding the mechanism of recurrent chromosomal rearrangments. An initial YAC contig extended from D15S18 to D15S12 and was comprised of 23 YACs and 21 STSs providing an average resolution of about one STS per 200 kb. To close two gaps in this contig, YAC screening was performed using two STSs that flank the gap between D15S18 and 254B5R and three STSs located distal to the GABRA5–149A9L gap. Additionally, we developed 11 new STSs, including seven polymorphic markers. Although several groups have developed whole-genome genetic and radiation hybrid maps, the depth of coverage for 15q11–q13 has been somewhat limited and discrepancies in marker order exist between the maps. To resolve the inconsistencies and to provide a more detailed map order of STSs in this region, we have constructed an integrated YAC STS-based physical map of chromosome 15q11–q13 containing 118 YACs and 118 STSs, including 38 STRs and 49 genes/ESTs. Using an estimate of 4 Mb for the size of this region, the map provides an average STS spacing of 35 kb. This map provides a valuable resource for identification of disease genes localized to this region as well as a framework for complete DNA sequencing.  相似文献   
84.
The biochemical activities of 8 lysosomal acid hydrolases in leukemic cells from 48 patients were examined. Characteristic alterations were found in α-mannosidase, β-galactosidase and N-acetyl-β-glucosaminidase activities of leukemic cells. The level of α-mannosidase activity was much higher in myelo(mono)genous leukemias (AML, AMoL, AMMoL, CML and CMMoL) than in lymphogenous ones (ALL, T-cell leukemia, hairy cell leukemia and CLL) without exception. The β-galactosidase activity also differed as a result of α-mannosidase, except in T-cell leukemia. In T-cell leukemia it was within the range of normal lymphocytes, but in the other lymphogenous leukemias it was significantly below normal. N-acetyl-β-glucosaminidase activity in myelo(mono)genous leukemic cells was above the range of normal granulocytes. The changes in these enzyme levels were consistent. The lymphocytic or myelocytic nature of three cases of acute undifferentiated leukemia could be determined by enzyme studies. In two cases it was lymphocytic and in one it was myelocytic. The enzymatic abnormalities were also found in morphologically mature neutrophils from patients with not only chronic types (CML, CMMoL) but also acute types (AMoL, AMMoL) of leukemias, and were similar to those of their respective leukemic cells. Analysis of lysosomal enzymes (at least three of those mentioned above), can elucidate one of the biochemical properties of leukemic cells and may be valuable in the differentiation of leukemias.  相似文献   
85.
Background & Aims: Interleukin (IL)-15 has been found to share many immunoregulatory activities in lymphocytes with IL-2. The aim of this study was to investigate IL-15 activity in organ cultures, localization of IL-15 messenger RNA (mRNA), and proliferation of lamina propria mononuclear cells (LPMCs) in response to recombinant IL-15 using the mucosal tissues obtained from patients with inflammatory bowel disease (IBD). Methods: The contents of IL-15, tumor necrosis factor α, and IL-2 in the culture supernatant of the rectal mucosal tissues were determined by an enzyme-linked immunosorbent assay. Expression of IL-15 mRNA was analyzed by in situ hybridization, and proliferative response of LPMCs to recombinant IL-15 was determined by [3H]thymidine incorporation into DNA. Results: Significantly greater IL-15 activity was detected in active IBD, and this elevation was also observed in inactive ulcerative colitis. In contrast, greater tumor necrosis factor α activity was observed only in active IBD, and IL-2 was not detected in organ cultures. In situ hybridization showed IL-15 mRNA in macrophages and epithelial cells in active IBD specimens, and recombinant IL-15 induced a dose-dependent proliferative response in LPMCs. Conclusions: Mucosal IL-15 may be involved in the pathogenesis of IBD as one of the important mediators in activation of mucosal immune cells.GASTROENTEROLOGY 1998;114:1237-1243  相似文献   
86.
Longitudinal relaxation time (T1) determined by 3.0-T magnetic resonance imaging of the tibialis anterior and extensor digitorum longus muscles increased gradually with muscle fatigue caused by three 120-s periods of repeated ankle dorsiflexion separated by 5-min rest periods. T1 values decreased in the recovery period, although they remained higher than the preexercise values. T1 values for the soleus muscle were unchanged throughout the experiment. Results suggest that muscle T1 values increase with increasing muscle fatigue.  相似文献   
87.
Oxygen reduction reaction (ORR) was investigated using polycrystalline gold (Au (poly)) electrode modified with chemisorbed iodine (I(ads)) submonolayer (sub I(ads)) in O2-saturated 0.1 M KOH solution. The sub I(ads) was tailored by potential-dependent partial reductive desorption of I(ads) from its full monolayer. The Au (1 1 1) facet of the Au (poly) electrode was considered to remain bared at the sub I(ads)/Au (poly) electrode. The interesting finding of the present study is that (unlike the bare Au (poly) electrode) the sub I(ads)/Au (poly) electrode exhibited a quasi-reversible two-electron reduction of O2 in alkaline media. The probable origin of the observed quasi-reversible behavior of the ORR is discussed. Experimental investigations were performed using cyclic and steady-state voltammetric, amperometric and coulometric techniques.  相似文献   
88.
89.
To determine the transmission route of Helicobacter pylori, one nude mouse was challenged by H. pylori, and then raised with nonchallenged nude mice in a single cage in a sterilized environment with and without exposure to their feces. After coraising for two and four weeks, all mice were killed to determine H. pylori in the stomach, saliva, and feces and to assess gastritis grade. Natural transmission of H. pylori occurred in 50% (2/4) and 70% (7/10) of mice after two weeks and four weeks of coraising when they were exposed to their feces. H. pylori was detected not only in the stomach but also in saliva and feces by PCR of all challenged and transmitted mice. However, no transmission occurred in mice not exposed to feces of a challenged mouse, while sharing food and water in a single cage. These findings suggest that the fecal–oral transmission route is important, at least in the animal model. Serum levels of anti-H. pylori urease IgG of the H. pylori-transmitted mice increased after coraising, and gastritis was observed in the stomach of both challenged and transmitted mice. We conclude that H. pylori bacteria are transmitted through the fecal–oral route from challenged to nonchallenged nude mice, resulting in gastritis.  相似文献   
90.
BACKGROUND/AIMS: The presence of antibodies to the 210-kDa glycoprotein of the nuclear pore complex (gp210) is highly indicative of primary biliary cirrhosis (PBC). However, the significance of anti-gp210 antibody titers for monitoring PBC remains unresolved. METHODS: We used an ELISA with a gp210 C-terminal peptide as an antigen to assess serum antibody titers in 71 patients with PBC. RESULTS: Patients were classified into three groups: Group A in whom anti-gp210 titers were sustained at a high level, Group B in whom anti-gp210 status changed from positive to negative under ursodeoxycholic acid (UDCA) therapy, Group C in whom anti-gp210 antibodies were negative at the time of diagnosis. The rate of progression to end-stage hepatic failure was significantly higher in group A (60%) as compared to groups B (0%) and C (4.2%). The sustained antibody response to gp210 was closely associated with the severity of interface hepatitis. The significance of anti-gp210 antibody was confirmed by National Hospital Organization Study Group for Liver Disease in Japan. CONCLUSIONS: The serial quantitation of serum anti-gp210-C-terminal peptide antibodies is useful for monitoring the effect of UDCA and for the early identification of patients at high risk for end-stage hepatic failure.  相似文献   
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