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21.
Background Atopic dermatitis (AD) is the most common form of eczema. As leukotriene mediators are involved in the inflammatory phase of atopic dermatitis, montelukast has been suggested as a possible therapy. Aim of the review To evaluate the safety and efficacy of montelukast off-label use for the treatment atopic dermatitis. Method A search was performed from database inception until March 2018 in six electronic databases for randomized-controlled-trials examining the use of montelukast for AD. Results Among 301 articles screened, 11 studies met the inclusion criteria and were included in the review. The study populations consist of paediatric and adult subjects with moderate-to-severe AD. Montelukast use was shown to improve symptoms such as pruritus in four studies. Another 2 studies reported that montelukast could improve symptoms similar to the standard regimen of topical steroid and oral antihistamine. However, five studies reported that montelukast had no effects in symptoms alleviation. The use of montelukast was associated with a similar safety profile to placebo and well-tolerated with minimal adverse effects. Conclusion There is limited evidence to suggest that the off-label use of montelukast is effective in treating moderate-to-severe AD. Further research with larger study populations employing standardized endpoint measuring instrument is warranted to further investigate the off-label use of montelukast in AD treatment. Until then, the use of conventional treatments including optimal daily skin hydration should remain the mainstay in the management of atopic dermatitis. In fact, for moderate-to-severe condition, steroid sparing immune-suppressants should still be used clinically until more effective and safer alternative is discovered.  相似文献   
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Fabian  I; Douer  D; Levitt  L; Kletter  Y; Greenberg  PL 《Blood》1985,65(4):990-996
Mitogen-stimulated murine spleen cells produce humoral substances capable of supporting murine hematopoiesis and pluripotent stem cell proliferation in vitro. Thus, we evaluated conditioned media generated by human spleen cells (SCM) in the presence or absence of mitogens for factors stimulatory for human pluripotent (CFU-GEMM), erythroid (BFU- E), and myeloid (CFU-GM) precursors. Two and one half percent to 10% SCM stimulated proliferation of all three types of precursor cells from nonadherent buoyant human marrow target cells. Mitogen-stimulated SCM augmented CFU-GM (175% to 225%), whereas CFU-GEMM and BFU-E growth was essentially unchanged. Cell separation procedures used to determine which cells provided these microenvironmental stimuli indicated that nonadherent mononuclear spleen cells provided the bulk of the CSF-GM, whereas adherent cells (95% nonspecific esterase + monocyte- macrophages) and nonadherent cells provided similar proportions of CSF- mix and erythroid burst-promoting activity (BPA). The nonadherent cells generating high levels of CSF-mix, BPA, and CSF-GM were predominantly Leu-1-negative, ie, non-T, cells. In the presence or absence of mitogens, SCM was a more potent source (1.3- to 3.8-fold) than peripheral leukocyte CM of the growth factors for the three progenitor cell types. Specific in situ cytochemical stains for analyzing morphology of myeloid colonies demonstrated that SCM stimulated the proliferation of the same types and proportions of colonies as human placental CM, suggesting that these CMs may contain similar CSF-GMs. These data show the contribution of spleen cell subsets to the generation of hematopoietic growth factors and the responsiveness of these cells to various mitogenic stimuli.  相似文献   
25.
OBJECTIVE: Attenuation changes on computed tomography (CT) in mediastinal lymph nodes (LN) may be related to lung alterations and functional impairment in silicosis. DESIGN: CT and clinical data of 41 (64.2 +/- 8.3 years) males with silicosis were retrieved. Attenuation type (calcified, hyperdense, normodense) and calcification pattern (central, eccentric, dense, eggshell, speckled) of mediastinal LN were evaluated; LN attenuation of uncalcified LNs quantified on CT in six LN stations. Nodular profusion (CT-NP) and progressive massive fibrosis (CT-PMF) were graded. Relationships between LN, CT, lung function and clinical parameters were determined. RESULTS: LN sites were paratracheal (n = 39), subcarinal (n = 39), tracheobronchial (n = 37), aortopulmonary (n = 37), hilar (n = 27), and peri-oesophageal (n = 21). LNs were calcified, hyperdense and normodense in 107, 85 and 54 LN stations, respectively. Uniformly calcified LN was most common, followed by speckled calcification. Central, eccentric and eggshell calcification was rare. CT-NP scores > or = 16 were associated with higher LN attenuation and number of calcified LN stations than CT-NP scores < 16. PMF had no influence over LN morphology or calcification pattern. LN attenuation correlated with CT-PMF (r = 0.36, P = 0.01), CT-NP (r = 0.54, P < 0.001) and DLCO/VA (r = -0.33, P = 0.02). CONCLUSION: Uniformly calcified and hyperdense LNs are common in silicosis, and eggshell LN calcification is rare. There are associations between LN attenuation and lung function impairment, and CT grades of nodular profusion and PMF.  相似文献   
26.
Funk  PE; Kincade  PW; Witte  PL 《Blood》1994,83(2):361-369
In suspensions of murine bone marrow, many stromal cells are tightly entwined with hematopoietic cells. These cellular aggregations appear to exist normally within the marrow. Previous studies showed that lymphocytes and stem cells adhered to stromal cells via vascular cell adhesion molecule 1 (VCAM1). Injection of anti-VCAM1 antibody into mice disrupts the aggregates, showing the importance of VCAM1 in the adhesion between stromal cells and hematopoietic cells in vivo. Early hematopoietic stem cells were shown to be enriched in aggregates by using a limiting-dilution culture assay. Myeloid progenitors responsive to WEHI-3CM in combination with stem cell factor (c-kit ligand) and B220- B-cell progenitors responsive to insulin-like growth factor-1 in combination with interleukin-7 are not enriched. We propose a scheme of stromal cell-hematopoietic cell interactions based on the cell types selectively retained within the aggregates. The existence of these aggregates as native elements of bone marrow organization presents a novel means to study in vivo stem cell-stromal cell interaction.  相似文献   
27.

Summary

The association between antidepressant use and hip fracture remains unclear. We conducted a systematic review to estimate Population Attributable Risks (PAR) for France, Germany, Italy, Spain, UK, and the USA. We report a heterogeneous prevalence of antidepressant use and related PARs, both lowest for Italy and highest for the USA.

Introduction

Antidepressant use has been associated with an increased hip fracture risk in observational studies. However, the potential contribution of antidepressant consumption on the population rate of hip fractures has not been described. Our aim was to estimate the impact of the use of different classes of antidepressants on the rate of hip fracture at a population-level in France, Germany, Italy, Spain, the UK, and the USA.

Methods

We conducted a systematic literature review to estimate the pooled relative risk (RR) of hip fracture according to use of antidepressants. Prevalence rates of antidepressant use (Pe) in 2009 were calculated for each country using the The Intercontinental Medical Statistics database and three public databases from Denmark, the Netherlands, and Norway. Both the RR and Pe were used to calculate PAR of hip fractures associated with antidepressant use.

Results

The literature review showed an increased risk of hip fractures in antidepressant users (RR, 1.7; 95 % confidence interval (CI), 1.5–2.0). Rates of antidepressant use showed considerable differences between countries, ranging from 4.4 % (Italy) to 11.2 % (USA) in the year 2009. The estimated PAR of antidepressants on hip fracture rates were 3.0 % (95 % CI, 2.0–4.1; Italy), 3.1 % (95 % CI, 2.1–4.3; Germany), 3.8 % (95 % CI, 2.6–5.3; France), 4.8 % (95 % CI, 3.3–6.5; Spain), 4.9 % (95 % CI, 3.4–6.8; UK), and 7.2 % (95 % CI, 5.0–9.9; USA). PARs differed for different types of antidepressants, with highest attributable risks for selective serotonin reuptake inhibitors.

Conclusions

These findings suggest that the potential contribution of antidepressant use to the population rate of hip fractures in the five large EU countries and the USA varies between 3 and 7 %.  相似文献   
28.
Lung tissue from 13 cases of unexplained non-immunological hydrops fetalis was examined by in situ hybridisation to detect parvovirus. Four specimens contained parvovirus DNA in cells in the blood vessel lumina and alveoli. Twenty six control cases were negative for parvovirus DNA. As there was no known epidemic of parvovirus infection during the study period, this suggests that parvovirus is a relatively common cause of non-immunological hydrops fetalis. In situ hybridisation may have a role in clinical medicine, particularly for retrospective investigations.  相似文献   
29.
Experimental lead intoxication is an important model for the study of cellular and molecular mechanisms of segmental demyelination in peripheral nerve. In this report we have compared pathological changes with the molecular and immunohistochemical expression of the proteins of compact and non-compact myelin in the demyelinating neuropathy induced in Sprague-Dawley rats after chronic administration (3 and 6 months) of lead acetate in drinking water. All the rats underwent the neurophysiological determination of the conduction velocity in the tail nerve at baseline and 3, 4.5 and 6 months after the beginning of the lead acetate administration. At the end of the treatment period the rats were sacrificed and sciatic nerve specimens were obtained. The neurophysiological study demonstrated a significant decrease in the nerve conduction velocity, which was already evident at the first determination (3 months) and persisted along the entire experiment. The neurophysiological results were in agreement with the pathological observations performed in the sciatic nerve, where several large demyelinated fibers were observed in the lead-intoxicated rats. Northern and Western blot analysis demonstrated that steady state mRNA and protein levels for P0, MBP, PMP22 and PLP were not changed comparing treated and control rats. Immunohistochemistry on teased fibers revealed that those proteins were distributed in areas of compact myelin along the internodes. In control fibers, as expected, MAG was found in the periaxonal cytoplasm, at nodes of Ranvier, and in the Schmidt-Lanterman incisures. In lead neuropathy, MAG was still limited to discrete regions, but the intensity of staining was reduced, in accordance with changes of paranodal structures. Immunohistochemical localization of other proteins of non-compacted myelin, including connexin-32, E-cadherin and β-catenin was also examined. Our data further suggest that chronic lead intoxication in the rat produces segmental demyelination due primarily to Schwann cell dysfunction.  相似文献   
30.

Introduction

Plasma selenium (Se) concentrations are reduced in critically ill surgical patients, and lower plasma Se concentrations are associated with worse outcomes. We investigated whether adjuvant Se supplementation in the form of sodium selenite could improve outcomes in surgical patients with sepsis.

Methods

In this retrospective study, all adult patients admitted to a 50-bed surgical ICU with severe sepsis between January 2004 and April 2010 were included and analysed according to whether they had received adjuvant Se supplementation, which was given at the discretion of the attending physician. When prescribed, Se was administered in the form of sodium selenite pentahydrate (Na2SeO3∙5H2O), in which 100 μg of Se corresponds to 333 μg of sodium selenite. A bolus of sodium selenite corresponding to 1,000 μg of Se was injected intravenously through a central venous line for 30 minutes, followed by infusion of 1,000 μg/day for 24 hours for 14 days until ICU discharge or death. We performed logistic regression analysis to investigate the impact of adjuvant Se supplementation on hospital mortality.

Results

Adjuvant Se was administered to 413 (39.7%) of the 1,047 patients admitted with severe sepsis. Age and sex were similar between patients who received adjuvant Se and those who did not. Compared with patients who did not receive adjuvant Se supplementation, patients who did had higher scores on the Simplified Acute Physiology Score II, a greater prevalence of cancer upon admission to the ICU and were more commonly admitted after abdominal surgery. Compared with patients who did not receive adjuvant Se, patients who did had higher hospital mortality rates (46% versus 39.1%; P = 0.027), and longer median (interquartile range (IQR)) ICU stays (15 days (6 to 24) versus 11 days (4 to 24); P = 0.01) and hospital lengths of stay (33 days (21 to 52) versus 28 days (17 to 46); P = 0.001). In multivariable analysis, adjuvant Se supplementation was not independently associated with favourable outcome (odds ratio = 1.19, 95% confidence interval = 0.86 to 1.65; P = 0.288).

Conclusions

In this retrospective analysis of a large cohort of surgical ICU patients with severe sepsis, adjuvant Se supplementation in the form of sodium selenite had no impact on in-hospital death rates after adjustment for confounders.  相似文献   
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