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61.
Adjunctive use of mitomycin C on endoscopic lacrimal surgery   总被引:6,自引:0,他引:6       下载免费PDF全文
AIMS—Endoscopic endonasal dacryocystorhinostomy (DCR) has some advantages over external DCR as a less invasive method with no skin incisions. But the success rate of the operation has not reached the level of external method. In this study, a wound healing inhibitor mitomycin C was used intraoperatively to prevent the closure of the osteum after the operation.
METHODS—Endoscopic endonasal DCR was performed on 40 eyes of 39 patients (26 female, 13 male). Mitomycin C was applied to the ostium in 14 of 23 patients who had undergone primary endoscopic DCR by means of a microdrill and in eight of 17 patients who had a revision endoscopic DCR secondary to a previously failed external DCR.
RESULTS—The postoperative follow up period was 9-27 (mean 18.2) months. The success rate of endoscopic DCR with intraoperative mitomycin C was 77.3%, whereas the success rate of endoscopic DCR without mitomycin C was 77.8%. The statistical analysis did not show a difference between the two groups according to the ostium size and their success rates.
CONCLUSIONS—Adjunctive use of a wound healing inhibitor is considered to increase the success rate of endoscopic endonasal DCR. Its intraoperative use seems to be easy and safe. But the study of this limited series shows no benefit in using it.

Keywords: mytomycin C; lacrimal surgery; dacryocystorhinostomy  相似文献   
62.
Depression is considered as a chronic and recurring illness with functional impairment, significant disability, morbidity and mortality. Despite the extensive research carried out on depression, its pathophysiology is still poorly understood. An important problem concerning research into depressive disorder is the lack of biological markers which could improve diagnosis or indicate a risk of developing depression or risk of relapse. Several reports indicated decreased zinc concentrations and even its deficit in clinical depression, so the measurement of the concentration of this element in the blood of patients was suggested as a useful and specific clinical marker of depression. The reported results indicated that the serum zinc level might be a marker of depression as a state (state marker) in treatment responsive patients. However, in drug-resistant depression a decreased concentration of zinc may be a marker of traits (trait marker). It seems, however, that the measurement of the concentrations of zinc might be in the future a component of the battery of tests; of markers of immune activation and oxidative stress rather than itself alone.  相似文献   
63.
Numerous data showed that 5-hydroxytryptamine-1A (5-HT1A) receptors couple to Galpha(o)/alpha(i) proteins for signal transduction. However, the alpha subunit isoforms really involved in 5-HT1A receptor coupling in brain remain to be identified. Moreover, regional differences in the functional characteristics of brain 5-HT1A receptors have been evidenced repeatedly. Because such differences could be due to variations in G proteins interacting with the same receptor, relevant approaches were used for identifying alpha subunits physically coupled to 5-HT1A receptors in different regions of the rat brain. Using immunoaffinity chromatography coupled to Western blot detection, 5-HT1A receptors were found to interact equally with Galpha(o) and Galpha(i3) in the cerebral cortex, mainly with Galpha(o) and weakly with Galpha(i3) in the hippocampus and exclusively with Galpha(i3) in the anterior raphe area. In the hypothalamus, 5-HT(1A) receptors seemed to be coupled to the latter two G proteins plus Galpha(i1) and Galpha(z). Complementary experiments based on an antibody capture technique coupled to both classic radioactivity and scintillation proximity assay detections showed that hippocampal 5-HT1A receptor stimulation induced 5'-O-(3-[35S]thio)triphosphate binding to immunoprecipitates with Galpha(i3) and Galpha(o) antisera. In the anterior raphe, such 5-HT1A receptor-mediated effect was obtained with Galpha(i3) antiserum only. These results demonstrated the existence of regional differences in the coupling of 5-HT1A receptors to G proteins in the rat brain. In the anterior raphe, 5-HT1A receptors seem to interact specifically with Galpha(i3), whereas in the hippocampus, they are mainly coupled to Galpha(o) proteins. Such a disparity in G-protein coupling might explain regional differences in adaptive regulations of brain 5-HT1A receptors.  相似文献   
64.
The authors prospectively analysed 50 patients with chronic anterior disc displacement without reduction, who underwent arthroscopic lysis and lavage of the temporomandibular joint (TMJ). Patients with symptoms lasting less than 1 year were assigned to Group A (n=28) and patients with symptoms lasting more than 1 year to Group B (n=22). The most common problems were inflammatory changes of synovial and retrodiscal tissue (Group A, 71%; Group B, 82%). Fibrous adhesions were present in 14% of Group A patients and 45% of Group B patients. Degenerative changes of the disc and articular surface were present in 4% of Group A patients and 32% of Group B patients. Mouth opening increased 123% from baseline in Group A, and 112% in Group B (P<0.05). Pain decreased significantly in both groups (Group A, 2.5 points; Group B, 1.68 points; P<0.05). In conclusion, almost all patients with chronic anterior disc displacement without reduction benefited from arthroscopic lysis and lavage of the TMJ. Patients with a shorter duration of symptoms problems benefited more than those with a longer duration. Arthroscopic lysis and lavage of the TMJ is safe and beneficial in chronic anterior disc displacement without reduction.  相似文献   
65.

Objective:

The aim of this study was to evaluate the degree of microbial contamination in packaged gutta-percha cones before and during use in clinical conditions.

Material and Methods:

Sealed packages of #15-40 gutta-percha cones were opened under aseptic laboratory conditions. Two gutta-percha cones from each size were randomly drawn and added to tubes containing glass beads and 750 μL of saline. The tubes were vortexed, serially diluted and samples of 250 μL were cultured on agar plates. The plates were incubated at 37°C for 3 days and colonies were counted. The initially sampled packages were distributed to 12 final year dental students. The packages were collected at the end of the first and the third clinical practice days and sampled as described above.

Results:

Baseline microbial counts did not exceed 3 CFU. At the end of the first and the third day, additional contamination was found in five and three of the packages, respectively. The ratio of contaminated packages at the first day and the third day was not significantly different (z-test; p > 0.05). The numbers of microorganisms cultured at the first day (8 ± 9.9 CFU) and the third day (4.5 ± 8.3 CFU) were not significantly different (Wilcoxon signed-rank test; p > 0.05). No significant correlation was found between the number of filled root canals and cultured microorganisms at either the first day (Spearman''s rho; r = 0.481, p = 0.113) or the third day (r = -0.034, p = 0.917).

Conclusions:

Gutta-percha cones taken directly from manufacturer''s sealed package harbored microorganisms. Clinical use of the packages has been found to be associated with additional contamination of the gutta-percha cones. The counts of cultured microorganisms did not correlate well with the number of filled root canals.  相似文献   
66.
OBJECTIVE: We aim to demonstrate that low dose growth hormone (GH) administered in i.v. pulses every 3h is able to normalize IGF-I levels in subjects with prolonged critical illness, after multiple trauma. We also ask whether it is possible to control glycaemia during such a treatment and how alanylglutamine (AG) supplementation influences plasma glutamine concentration. METHODS: We used a prospective double-blind (group 1 vs. 2), randomized trial with an open-label control arm (group 3). Thirty multiple trauma patients (median age: 36, 42, 46 years) were randomized on day 4 after trauma to receive (group 1, n=10) i.v. AG supplementation (0.3 g/kg day from day 4 till 17) and i.v. GH (0.05 mg/kg day divided into 8 boluses, maximum dose at 3 AM, administered on days 7-17) or AG and placebo (group 2, n=10). Group 3 (n=10) received isocaloric isonitrogenous (proteins 1.5 g/kg day) nutrition without AG. Glycaemia was controlled by i.v. insulin infusion according to a routine protocol. RESULTS: GH treatment caused an increase of IGF-I (from median 169 on day 4 to 493 ng/ml on day 17), IGFBP-3 (from 2.4 to 3.2 microg/ml) and a fall in IGFBP-1 (from 11.5 to 3.1 microg/ml), whilst in both groups 2 and 3 these indices remained unchanged. At the end of the study (day 17) IGF-I and IGFBP-1 differed significantly among groups (p=0.008 resp. p=0.010, Kruskal-Wallis). Plasma glutamine remained below the normal range through the study in all groups (median: 0.18-0.30 mM), but had a tendency to rise in group 2 in contrast with a fall in groups 1 and 3 (NS). Group 1 required more insulin (p<0.01) than did the control group but median glycaemia was only 0.4-0.5 mM higher in group 1 (6.5 mM) than in groups 2 and 3 (6.1 resp. 6.0 mM). CONCLUSIONS: GH (0.05 g/kg day) administered in i.v. pulses is able to normalize IGF-I levels in subjects with prolonged critical illness after trauma. During this treatment, the standard dose of AG prevents worsening of plasma glutamine deficiency and glucose control is possible using routine algorithms, but it requires higher insulin doses.  相似文献   
67.
探讨内皮素(ET)、一氧化氮/一氧化氮酶( NO/NOS)在糖尿病与血管病变患者中的变化。ET采用放射免疫分析法,NO/NOS采用酶法。结果是:(1)糖尿病组ET水平(68.80±37.35)pg/mL)较对照组(41.70±21.50pg/mL)显著升高(P<0.001);NOS水平(2.75±1.49U/mL)明显高于对照组(1.12±0.56U/mL),P<0.01;NO水平(49.32± 16.32μmol/L)明显低于对照组(54.60 ±15.60μmol/L),P<0.05。(2)糖尿病合并血管病变组ET水(80.1140.25pg/mL)显著高于无并发症组(62.73±24.29pg/mL),P<0.001;NOS水平(4.02 ± 0.59U/mL)明显高于无并发症组(2.51±1.19U/mL),P<0.001;NO水平(42.25 ± 10.10/μmol/L)明显低于无并发症组(52.16±14.59mol/L,P<0.05;NO/NOS(11.99±7.05)明显低于无并发症组(26.9±13.15),P<0.001提示 ET、NO/NOS与糖尿病的发生和发展有关,联合检测不仅可作为糖尿病及其血管并发症的重要依据,还将有助于糖尿病合并血管病变的预防和治疗。  相似文献   
68.
Zusammenfassung Die chronischen myeloproliferativen Erkrankungen (CMPE) sind neoplastische Erkrankungen der hämatopoetischen Stammzelle. Sie umfassen die chronische myeloische Leukämie (CML), die Polycythaemia vera, die essentielle Thrombozythämie, die primäre Osteomyelofibrose und Übergangsformen innerhalb dieser Erkrankungen sowie zwischen den CMPE und den Myelodysplasien. Hauptziele der Initialdiagnostik sind die genaue Klassifizierung der Erkrankung, die Erfassung von Risiko- und Prognosefaktoren sowie die Charakterisierung des malignen Klons mittels Zytogenetik und molekulargenetischer Methoden. Herkömmliche Therapeutika für alle CMPE sind Hydroxyurea und Interferon-. Bei der CML führt die gezielte Hemmung der BCR-ABL-Tyrosinkinase mit Imatinib klinisch zu hohen Ansprechraten. Die bisher einzige kurative Therapie für alle Entitäten ist die allogene Stammzelltransplantation. Bei der CML sollte die Indikation auf der Basis der neueren Risikoscores gestellt werden. Bei den BCR-ABL-negativen CMPE ist sie nur bei ungünstigem Krankheitsverlauf in Erwägung zu ziehen.
  相似文献   
69.
Objectives : The frequency of chromosomal aberrations (CA) and micronuclei (MN) in peripheral blood lymphocytes was compared in two groups of persons occupationally exposed to tritium either through the use of luminous paints or in the weapons industry, with the aim of finding a correlation between the CA and MN assays, the extent of radiation hazard, and the duration of occupational exposure to chemical forms of tritium and the ability of the latter to induce hazards in human lymphocytes. Methods : CA analysis and the cytochalasin B micronucleus test were performed. Urinary tritium in both groups was measured using a liquid scintillation method. For purposes of comparison, 2 control groups (40 persons) were examined; 24 exposed individuals were matched to their controls according to age, sex, and smoking habits. Results: Values recorded for the frequency of CA in the group of workers handling tritium in luminous dial painting were 0.015 ± 0.014 dicentrics/cell, 0.023 ± 0.017 total unstable CA/cell, and 0.035 ± 0.019 MN/binucleated cell. Urinary levels of tritium in this group of employees ranged from 1.35 to 9.43 MBq/l. As compared with their matched controls, in these workers the differences in the yield of CA as well as in MN were statistically highly significant (P<0.005 and P<0.003, respectively). The same parameters analyzed in workers employed in the armament industry gave values of 0.001 ± 0.003 dicentrics/cell, 0.010 ± 0.008 total unstable CA/cell, and 0.021 ± 0.029 MN/binucleated cell. No detectable concentration of urinary tritium was found. As compared with their matched controls, in these workers the differences were also statistically significant (P<0.027 and P<0.012, respectively). The yield of CA, particularly the yield of dicentrics, was significantly higher (P<0.005) in the group of luminous dial painters as compared with the weapons industry workers. The difference found in the yield of MN between the two groups of workers was also statistically significant (P<0.084). Intercontrol differences in the yields of spontaneous CA as well as in MN were insignificant (P<0.683 and P<0.735, respectively). The results are discussed with respect to individual variations in the response to low doses of ionizing radiation, disorders in the handling of radionuclides, the duration of occupational exposure, and the chemical properties of the radionuclides used. Conclusion : Tritium in the chemical form of luminous paint is a more powerful clastogenic agent than tritium gas. Statistical analysis demonstrated that lymphocyte effects are due to the concentration of tritium in urine rather than to the duration of occupational exposure. Since the radiation hazard measured by the MN assay did not differ from that determined by the CA assay, the MN test can be recommended as a rapid assay for screening purposes in cases of occupational exposure to low radiation doses. Received: 20 November 1996 / Accepted: 1 August 1997  相似文献   
70.
目的观察红景天对高原性肺动脉高压大鼠肺小动脉转化生长因子(TGF)-β1达的影响,探讨其对高原性怖动脉高压的干预作用。方法将30只健康雄性Wistar大鼠随机分为对照组、低氧组、红景天组,每组10只。对照组于四川成都市(海拔500m)饲养,低氧组和红景天组于西藏拉萨市(海拔3700 m)饲养。红景天组每天给予红景天溶液灌胃,对照组和低氧组每天给予生理盐水灌胃。3组大鼠存灌胃30d后,分别测量平均肺动脉压力(mPAP)、右心肥大指数(RV/(LV+S))及肺小动脉管壁厚度百分比(WT),并应用免疫组织化学法检测肺小动脉TGF-β1达。结果低氧组mPAP、RV/(LV+S)和肺小动脉WT明显高于对照组(P〈0.05),红景天组低于低氧组(P〈0.05);低氧组肺小动脉管壁TGF-β1达高于对照组(P〈0.05),红景天组肺小动脉管壁TGF-β1表达低于低氧组(P〈0.05)。结论红景天通过减少大鼠肺小动脉TGF-β1表达,对大鼠高原性肺动脉高压的形成有一定的干预作用。  相似文献   
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