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排序方式: 共有1287条查询结果,搜索用时 234 毫秒
81.
Abstract: The aim of this work was to study the effects and side effects of gemcitabine (2′,2′‐difluorodeoxycytidine, dFdC), a pyrimidine synthesis inhibitor, on skin lesions of a herpes simplex virus (HSV)‐induced Adamantiades–Behçet's disease (ABD)‐like mouse model. For the dose‐escalation study, ICR mice were treated intraperitoneally with dFdC over 5 days. For the efficacy study, ICR mice were inoculated with HSV and classified as having ABD according to a revised Japanese classification, and then 18 ABD mice were randomly assigned to placebo, 0.06 or 0.12 µg of dFdC/day over 5 days. Serum levels of interleukin‐4 (IL‐4), IL‐6, IL‐10, interferon‐γ (IFN‐γ), and tumor necrosis factor‐α (TNF‐α) were determined using enzyme‐linked immunosorbent assay. After application of 3 µg of dFdC over 5 days, alanine aminotransferase increased (P = 0.032), but all other kidney and liver parameters were unchanged. In ABD mice, 5 days of dFdC treatment with 0.06 or 0.12 µg of dFdC/day resulted in a dose‐dependent improvement of cutaneous manifestations by more than 60% (P = 0.017). There was no significant change in cytokine levels, and none of the cytokine levels correlated with response to treatment. Moreover, dFdC shows promising effects to improve cutaneous lesions in the HSV‐induced ABD‐like mouse model. In this animal model, effects of dFdC on the cytokine profile remained inconclusive.  相似文献   
82.
PURPOSE: To elucidate the expression pattern of different types of metabotropic P2Y receptors in the adult rat retina. METHODS: Qualitative RT-PCR was used to investigate the expression profile of different P2Y receptor subtypes (P2Y1, P2Y2, P2Y4, and P2Y6), and in situ hybridization studies were performed to show their cellular localization within the retina. Immunohistochemical staining was used to detect the corresponding P2Y proteins (P2Y1, P2Y2, and P2Y4) and their cellular localization. Southern blot analysis and sequencing verified the identity of the P2Y PCR products. RESULTS: RT-PCR revealed the presence of P2Y1, -2, -4, and -6 mRNA in the neural retina and the retinal pigment epithelium (RPE) and choroid. In situ hybridization showed labeling in the retinal ganglion cell layer for all four P2Y receptor subtypes, although the intensity varied. In addition, staining for P2Y1, -4, and -6 mRNA was shown in the inner nuclear layer, but was absent for the P2Y2 receptor subtype. Immunohistochemistry showed intense staining for P2Y1, -2, and -4 in the ganglion cell layer and the outer plexiform layer. There was also a specific subtype staining in the inner plexiform layer (P2Y2, -4), the inner (P2Y1, -4) and outer (P2Y1) nuclear layers and the inner segments of the photoreceptors (P2Y1, -2). discussion. The data suggest that extracellular nucleotides may play complex roles as autocrine-paracrine mediators and may have neuromodulatory effects in the retina through metabotropic P2Y receptors.  相似文献   
83.
OBJECTIVE: We evaluated the safety and efficacy of the fibrin sealant Beriplast P (FSBP; Aventis-Behring) for hemostasis in anastomosis of polytetrafluoroethylene (PTFE) grafts to the femoral artery. METHODS: In a single-blinded randomized prospective multicenter clinical trial, FSBP was compared with thrombin-soaked gelatin sponge (TSG) for efficacy in stopping bleeding from needle or suture holes in PTFE grafts after anastomosis to the femoral artery. Patients were randomized to FSBP application, which requires a 3-minute period of arterial clamping to enable the fibrin clot to adhere, or to TSG application, which requires pressure from gauze sponges, after completion of the femoral artery anastomosis. The primary end point was hemostasis, defined as absence of any detectable bleeding as judged by the operating surgeon, by 4 minutes after randomization. Secondary end points included actual time from randomization to hemostasis, time to beginning of wound closure, measured blood loss (weighed sponges), incidence of recurrent bleeding, stay in the intensive care unit, and hospital length of stay. Data were analyzed with the intention-to-treat method. RESULTS: Two hundred thirty-five subjects were enrolled at 26 medical centers; 34 were subsequently excluded from the study. Of the 201 randomized subjects, 100 received FSBP and 99 received TSG. Hemostasis was achieved by 4 minutes in 64 subjects (63%) in the FSBP group and 40 subjects (40%) in the TSG group (P =.0018). In the FSBP group, compared with the TSG group, time to hemostasis was shorter (median, 4.0 minutes; 95% confidence interval [CI], 3.8-4.18 minutes vs median, 5.6 minutes, 95% CI, 4.5-7.0; P =.008), blood loss was less (mean, 4.0 +/- 29.7 g vs mean, 15.6 +/- 28.4 g; P <.0001), and time to wound closure was shorter (median, 15 minutes; 95% CI, 10.47-18.67 minutes vs median, 22.8 minutes; 95% CI, 18.67-30.67; P =.005). There were no differences in recurrent bleeding or any other adverse events. There was no significant difference in ICU stay, but hospital length of stay was shorter in the FSBP group compared with the TSG group, and the difference approached significance (median, 6.5 days; 95% CI, 5.00-7.00 days vs median, 7.0 days; 95% CI,. 6.00-8.00 days; P =.0565). CONCLUSION: FSBP is more effective than TSG for achieving hemostasis of needle or suture hole bleeding from PTFE femoral artery grafts.  相似文献   
84.
This prospective trial aimed to evaluate the therapeutic effects and systemic toxicities of capecitabine monotherapy and capecitabine treatment combined with biological response modifiers in patients with metastatic renal cell carcinoma. Fifty-four patients suffering from metastatic renal cell carcinoma progressing under first-, second- or third-line treatment entered the trial. Capecitabine was given orally at a dose of 2500 mg/m2 daily divided into two doses for 14 days, followed by a 7-day rest in the monotherapy as well as in the combination treatment. This schedule was repeated in 3-week cycles. The combination therapy consisted of capecitabine and an immunotherapy treatment, which consisted either of interferon (IFN)-gamma1b (100 mg/day) administered consecutively 5 times weekly during weeks 1 and 2, and recombinant interleukin (IL)-2 (4.5 MU/day) administered on 4 consecutive days during weeks 3 and 4, every 6 weeks, or IFN-alpha (6 MioIE/day) administered 3 times a week. Fifty-two patients are now evaluable for response and 54 patients for toxicity. We observed a partial response to treatment in five patients (9.6%), minor response in five patients (9.6%), stable disease in 32 patients (61.6%) and only 10 patients (19.2%) showed continued disease progression despite treatment. Outpatient capecitabine was well tolerated. We did not observe any WHO grade IV toxicities. We conclude that capecitabine monotherapy and capecitabine treatment in combination with biological response modifiers appear to be effective regimens with favorable toxicity profiles in patients with advanced renal cell carcinoma. Capecitabine monotherapy seems to be superior than the combination treatment because of its easier application form.  相似文献   
85.
Homko CJ  Cheung P  Boden G 《Diabetes》2003,52(2):487-491
To study effects of sex on free fatty acid (FFA)-induced insulin resistance, we have examined the effects of acute elevations of plasma FFA levels on insulin-stimulated total body glucose uptake in nine healthy young women. Euglycemic-hyperinsulinemic (approximately 500 pmol/l) clamps were performed for 4 h with coinfusion of either lipid/heparin (L/H) to acutely raise plasma FFA levels (from approximately 600 to approximately 1,200 micro mol/l) or saline/glycerol to lower fatty acids (from approximately 600 to approximately 50 micro mol/l). L/H infusion inhibited insulin-stimulated glucose uptake (determined with [3-(3)H]glucose) and glycogen synthesis by 31 and 40%, respectively (P < 0.01), almost completely abolished insulin suppression of endogenous glucose production (EGP) (13.6 vs. 10.0 micro mol x kg(-1) x min(-1), NS), prevented the insulin induced increase in carbohydrate oxidation (8.1 vs. 7.4 micro mol x kg(-1) x min(-1), NS), and stimulated fat oxidation (from 3.6 to 5.1 micro mol x kg(-1) x min(-1), P < 0.01). These data showed that acute increases in plasma FFA levels inhibited the actions of insulin on glucose uptake, glycogen synthesis, and EGP in women to a degree similar to that previously reported in men. We conclude that at insulin and FFA levels in the postprandial range, women and men were susceptible to FFA-induced peripheral and hepatic insulin resistance.  相似文献   
86.
Cerebral involvement of systemic mastocytosis and intracranial sarcoma of myelogenic origin are well known entities. An 8-year-old girl with an isolated cerebral mast cell tumor is presented. Specific histopathologic stains were used to confirm the diagnosis detecting immunophenotype and proliferative activity. Treatment with irradiation, intrathecal cytarabine, and interferon-alpha2b did not induce regression whereas polychemotherapy did. Systemic combination chemotherapy led to marked transient tumor regression in this proliferating mast cell sarcoma in an unusual intracranial location.  相似文献   
87.
Many new techniques and applications in magnetic resonance imaging of the body have been introduced in the last decade and, at the same time, a wide variety of contrast media have become available for different imaging strategies. The aim of this article is to review the current use of contrast agents in body MRI. Extracellular and hepatobiliary gadolinium chelates, as well as iron oxide-based contrast media, are discussed and their use in different areas of the body highlighted. Topics to be covered include breast imaging, imaging of the thorax and the mediastinum, and imaging of the upper abdomen, kidneys, and pelvis. Established applications as well as new emerging indications are discussed, and the impact on improved detection and characterization of pathologies is demonstrated.  相似文献   
88.
To determine how a progressive loss of photoreceptor cells and the concomitant loss of glutamatergic input to second-order neurons can affect inner-retinal signaling, glutamate receptor expression was analyzed in the Royal College of Surgeons (RCS) rat, an animal model of retinitis pigmentosa. Immunohistochemistry was performed on retinal sections of RCS rats and congenic controls between postnatal (P) day 3 and the aged adult (up to P350) using specific antibodies against N-methyl-D-aspartate (NMDA) subunits. All NMDA subunits (NR1, NR2A-2D) were expressed in control and dystrophic retinas at all ages, and distinct patterns of labeling were found in horizontal cells, subpopulations of amacrine cells and ganglion cells, as well as in the outer and inner plexiform layer (IPL). NRI immunoreactivity in the inner plexiform layer of adult control retinas was concentrated in two distinct bands, indicating a synaptic localization of NMDA receptors in the OFF and ON signal pathways. In the RCS retina, these bands of NRI immunoreactivity in the IPL were much weaker in animals older than P40. In parallel, NR2B immunoreactivity in the outer plexiform layer (OPL) of RCS rats was always reduced compared to controls and vanished between P40 and P120. The most striking alteration observed in the degenerating retina, however, was a strong expression of NRI immunoreactivity in Müller cell processes in the inner retina which was not observed in control animals and which was present prior to any visible sign of photoreceptor degeneration. The results suggest functional changes in glutamatergic receptor signaling in the dystrophic retina and a possible involvement of Müller cells in early processes of this disease.  相似文献   
89.
RATIONALE AND OBJECTIVES: To optimize the intraluminal signal intensity of a nitinol stent by performing contrast-enhanced three-dimensional magnetic resonance angiography (CE-MRA) with varying flip angles (FAs). METHODS: Contrast-enhanced magnetic resonance angiography at 1.5 T and FAs of 30 degrees, 100 degrees, and 150 degrees was performed on five sheep with 10 iliac nitinol stents (Memotherm-FLEXX). Maximum-intensity projections (MIPs) and composite images of MIPs were performed and compared. RESULTS: Reconstructed MIPs at an FA of 150 degrees showed a slightly disturbed lumen visibility inside the stent accompanied by low-grade lumen visibility outside the stent and vice versa for an FA of 30 degrees. Composite images of a 30 degrees MIP added to a 150 degrees MIP resulted in improved image quality compared with the standard MIP of a single FA. CONCLUSIONS: Signal loss due to radiofrequency shielding inside nitinol stents imaged by CE-MRA can be reduced by applying high FAs. Composite MIP images allow simultaneous visualization of the lumen inside as well as outside the stent.  相似文献   
90.
PURPOSE: To assess the effects of short- and long-term changes in auditory feedback on vowel and sibilant contrasts and to evaluate hypotheses arising from a model of speech motor planning. METHOD: The perception and production of vowel and sibilant contrasts were measured in 8 postlingually deafened adults prior to activation of their cochlear implant speech processors, 1 month postactivation, and 1 year postactivation. Measures were taken postactivation both with and without auditory feedback. Contrast measures were also made for a group of speakers with reportedly normal hearing speaking with masked and unmasked auditory feedback. RESULTS: Vowel and sibilant contrasts, measured in the absence of auditory feedback after 1 month of prosthesis use, were diminished compared with their values measured before prosthesis. Contrasts measured in the absence of auditory feedback after 1 year's experience with the prosthesis were increased compared with their values after 1 month's experience. In both time samples, contrasts were enhanced when auditory feedback was restored. CONCLUSION: The provision of prosthetic hearing to postlingually deafened adults impaired their phonemic contrasts at first, as their auditory feedback had novel characteristics. Once auditory feedback became recalibrated with prosthesis use, it could, in turn, revise feedforward commands that control the contrasts in its absence.  相似文献   
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