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951.

Backgrounds  

Disseminated Penicillium marneffei infection is one of the most common HIV-related opportunistic infections in Southeast Asia. Immune reconstitution inflammatory syndrome (IRIS) is a complication related to antiretroviral therapy (ART)-induced immune restoration. The aim of this report is to present a case of HIV-infected child who developed an unmasking type of IRIS caused by disseminated P. marneffei infection after ART initiation.  相似文献   
952.

Introduction

In Asian population, facial structure may contribute to the primary pathophysiology of obstructive sleep apnea (OSA). We hypothesized that sleep position may have more effect on OSA in Asians compared to the Western population. If this hypothesis is accurate, positional therapy will have a major impact on treatment of OSA among Asians.

Patients/methods

We reviewed 263 polysomnographic studies from our laboratory from January 1, 2010 to June 30, 2010. Criteria for positional and non-positional OSA were (1) supine respiratory disturbance index (RDI)/non-supine RDI ??2 and total RDI ??5 and (2) supine RDI/non-supine RDI <2 and total RDI ??5, respectively. We aimed to determine the difference in baseline characteristics, polysomnographic findings, and predictors for positional OSA.

Results

We found 144 patients diagnosed with OSA (RDI ??5), and 96 patients met the criteria for positional OSA (67%), in which in almost half of these patients (47%), RDI was normalized (RDI?<?5) in non-supine position. Snoring frequency were significantly lower among positional OSA and OSA was less severe indicated by lower RDI and arousal index, higher mean and nadir oxygen saturation, and higher %NREM3. We also found that low snoring frequency (less than 20% of total sleep time) was a significant predictor for positional OSA (odd ratio of 3.27; p?=?0.011), contrarily to low mean oxygen saturation (<95%) which was found to be a negative predictor (odd ratio of 0.31; p?=?0.009). Among OSA patients, low RDI (<15) was a significant predictor for normalization of RDI in non-supine position (odd ratio of 8.77; p?=?<?0.001), contrarily to low mean oxygen saturation (<95%) which was also found to be a negative predictor (odd ratio of 0.13; p?=?0.001).

Conclusion

Positional OSA is very prevalent and noted in almost 70% of our patients. Low snoring frequency was noted to be a positive predictor for positional OSA, contrarily to low mean oxygen saturation which was found to be a negative predictor. These findings are encouraging that positional therapy can be very beneficial as the treatment modality for OSA among Asians.  相似文献   
953.
Background.?Severe falciparum malaria with human immunodeficiency virus (HIV) coinfection is common in settings with a high prevalence of both diseases, but there is little information on whether HIV affects the clinical presentation and outcome of severe malaria. Methods.?HIV status was assessed prospectively in hospitalized parasitemic adults and children with severe malaria in Beira, Mozambique, as part of a clinical trial comparing parenteral artesunate versus quinine (ISRCTN50258054). Clinical signs, comorbidity, complications, and disease outcome were compared according to HIV status. Results.?HIV-1 seroprevalence was 11% (74/655) in children under 15 years and 72% (49/68) in adults with severe malaria. Children with HIV coinfection presented with more severe acidosis, anemia, and respiratory distress, and higher peripheral blood parasitemia and plasma Plasmodium falciparum histidine-rich protein-2 (PfHRP2). During hospitalization, deterioration in coma score, convulsions, respiratory distress, and pneumonia were more common in HIV-coinfected children, and mortality was 26% (19/74) versus 9% (53/581) in uninfected children (P?相似文献   
954.

目的:研究角膜胶原交联术治疗圆锥角膜的疗效和安全性。

方法:对2015-04/2018-08在泰国朱拉隆功国王纪念医院行角膜胶原交联术的圆锥角膜患者病历进行回顾性分析。评估术前和术后1a的视力、屈光度、角膜地形图、高阶像差(HOA)、地形图参数和角膜密度。根据患者年龄是否小于24和30岁、基线角膜最大曲率(Kmax)是否小于55 D、基线最佳矫正视力(BCVA)是否小于0.3 LogMAR分组评估年龄、基线Kmax和BCVA对手术疗效的影响。分析术前Kmax、Kmean、平均等效球镜度数(MRSE)、视力、角膜最薄点厚度值、Kmax的变化以及相关参数的变化与角膜密度测量值变化之间的关系。P<0.05具有统计学意义。

结果:共155例患者185眼纳入研究,其中119例男性,36例女性。根据Amsler-Krumeich进行分类,1期和2期占优势(分别为37.84%和35.14%)。术后1a,平均裸眼视力(UCVA)提高0.1 LogMAR(P<0.05)。与基线BCVA较好组(术前BCVA<0.3 LogMAR)相比,基线BCVA较差组(术前BCVA≥0.3 LogMAR)术后BCVA改善大于0.2 LogMAR的眼数较多(78.26% vs 21.74%,P<0.05)。平均Kmax比基线下降2.36 D(P<0.05)。术前Kmax≥55 D的患眼术后Kmax下降超过2.0 D的眼数占比73%。距角膜顶点6 mm处角膜HOA下降0.40(P<0.05)。术后1mo~1a,0~6 mm区角膜密度测量值持续增加。术后1a,角膜密度的增加与最薄点厚度的减少呈线性相关。表面变异指数、高度非对称性指数、圆锥角膜指数、高度轴偏心指数在术后1a时下降(P<0.05)。术后1a,手术成功率为90.24%。术后1wk、1、3、6mo、1a角膜混浊发生率分别为11.35%、30.27%、15.67%、10.27%、2.16%。无角膜水肿发生,但有1例无菌性角膜炎患者。

结论:角膜胶原交联术可有效治疗圆锥角膜,使角膜变平、重塑,提高视力、HOA和角膜形态指数,晚期圆锥角膜Kmax也明显降低。  相似文献   

955.
Effects of germination time (3, 5 and 7 days) and kilning temperature (40, 50 and 60 °C) on the malting characteristics, biochemical properties and structural properties of HomChaiya rice were examined. Malting potential in terms of germination rate and germination capacity increased as the germination period of rice was prolonged. Diastatic potential, hot water extract and malting loss of rice gradually increased with germination time and with kilning temperature; in contrast, malting yield and viscosity of the samples decreased. Germination time significantly increased the α-amylase activity, but β-amylase activities increased when kilned at different temperatures. Total starch decreased and reducing sugar increased in rice with prolonged germination, and furthermore, the kilning temperature significantly influenced these changes. Higher kilning temperature and prolonged germination period increased the protease activity in rice, and consequently, soluble protein and free amino acids also increased. Among the twelve identified amino acids in the HomChaiya rice, aspartic acid, glutamic acid, asparagine, serine, arginine, isoleucine, tyrosine, and phenylalanine increased with germination time and kilning temperature. FTIR results showed that increased germination time and kilning temperature unfolded the carbohydrates, which is consistent with the enzymatic (α- and β-amylase) activities. XRD results also found higher peak intensities for rice when germinated longer and kilned at a higher temperature. The crystallinity of malted rice decreased with germination time. Ultrastructural changes showed that starch granules are more vulnerable to enzymatic attack upon extended germination time and at higher kilning temperatures.

Effects of germination time (3, 5 and 7 days) and kilning temperature (40, 50 and 60 °C) on the malting characteristics, biochemical properties and structural properties of HomChaiya rice were examined.  相似文献   
956.
Titanium dioxide is one of the most promising materials for many applications such as photovoltaics and photocatalysis. Non-metal doping of TiO2 is widely used to improve the photoconversion efficiency by shifting the absorption edge from the UV to visible-light region. Here, we employ hybrid density-functional calculations to investigate the energetics and optical properties of carbon (C) impurities in rutile TiO2. The predominant configurations of the C impurities are identified through the calculated formation energies under O-poor and O-rich growth conditions. Under the O-poor condition, we find that C occupying the oxygen site (CO) is energetically favorable for Fermi-level values near the conduction band minimum (n-type TiO2), and acts as a double acceptor. Under the O-rich condition, the Ci–VTi complex is energetically favorable, and is exclusively stable in the neutral charge state. We also find that interstitial hydrogen (Hi) can bind to CO, forming a CO–Hi complex. Our results suggest that CO and CO–Hi are a cause of visible-light absorption under oxygen deficient growth conditions.

The substitutional C on O site and its complex with H are a cause of visible-light absorption in rutile TiO2.  相似文献   
957.
Fluoride contamination has been recognised as one of the major problems worldwide, imposing a serious threat to human health and affecting the safety of drinking water. Adsorption is one of the widely considered appropriate technologies for water defluorination. The present study describes the preparation of a zirconium-based metal organic framework (MOF-801) adsorbent using a solvothermal method and its adsorption efficiency for removal of fluoride ions from water. The morphology of MOF-801 was characterized by PXRD, FESEM and XPS, and the pore structure and surface area were calculated according to BET. It was found that the synthesized MOF-801 showed the distinguishable octahedral shape particle with a lattice spacing of 0.304 nm, indicative of (011) planes of ZrO2. Adsorption studies were carried out to study the defluorination effectiveness by varying contact time (30–150 min), adsorbent dose (0.3–1.5 g L−1), adsorbate concentration (5–25 mg L−1), as well as kinetics and isotherms. The maximum removal efficiency for fluoride using MOF-801 at equilibrium was found to be 92.3%. Moreover, the adsorption kinetic studies indicate that the overall fluoride adsorption process was best described by pseudo-second-order kinetics. The adsorption data were well-fitted with the Langmuir isotherm model (R2 = 0.9925) with maximum adsorption capacity of 19.42 mg g−1. The synthesized MOF-801 had good reusability and was used in up to four cycles for fluoride removal attaining around 79% removal efficiency after the fourth cycle. All the results suggested that the synthesized MOF-801 has potential to be an excellent adsorbent for wastewater defluorination treatment.

A facile solvothermal method is used to prepare octahedral MOF-801 with a lattice spacing of 0.304 nm representative of ZrO2 (011) planes for water defluorination.  相似文献   
958.
Poly(3,4-ethylenedioxythiophene)polystyrene sulfonate (PEDOT:PSS) is often used as a hole injection and extractor for various organic electronic devices. This study investigated whether it is possible to n-dope PEDOT:PSS with barium acetylacetonate (Ba(acac)2) to change its work function so that to be more suitable for electron injection and extraction. Molecular dynamics simulations suggested that barium cations can interact with the aromatic rings of PEDOT and the negatively charged sulfonate in PSS. At high doping concentration, we found that PEDOT became dedoped and precipitated resulting in a clear solution after filtration. The absence of the absorption peak of PEDOT at 263 nm indicates the removal of PEDOT after filtration. The shift in O 1s to a lower binding energy as seen in X-ray photoelectron spectroscopy suggested that the polystyrene sulfonic acids are being ionized to form barium polystyrene sulfonate (Ba–PSS). By spin-coating the solution on top of indium tin oxide, the work function can be adjusted to as low as 3.6 eV. The ability of such a mixture to inject and extract electrons is demonstrated using 2,7-bis(diphenylphosphoryl)-9,9′-spirobifluorene as an electron transporting layer. We attributed the lowering of the work function as the result of the formation of an interfacial dipole as large as 1.37 eV at the ITO/Ba–PSS interface.

Modification of poly(3,4-ethylenedioxythiophene)polystyrene sulfonate as electron injection layer.  相似文献   
959.
In this work, we developed the first ultrasound technique enhanced smartphone application for highly sensitive determination of hydrogen peroxide (H2O2). The measurement technique is based on the change in color intensity due to the transformation of tetramethylbenzidine (TMB) to oxidized tetramethylbenzidine (oxTMB) by the oxidation process with hydroxyl radical (OH˙) from the oxidation etching of silver nanoparticles (AgNPs) and its ultrasound usability. The oxTMB product occurs without peroxidase and can be detected with a saturation channel using HSV methodology via the application of a smartphone. To prove the peroxidase mimic property, our proposed method was also validated by determination of certain biomolecules, including glucose, uric acid, acetylcholine and total cholesterol, of which the known amounts are a valuable diagnostic tool. The proposed method provided the lowest limits of detection (LOD) of 2.0, 5.0, 12.50, 7.50, and 10.0 nmol L−1 for H2O2, glucose, uric acid, acetylcholine, and cholesterol, respectively, when compared with LODs obtained from other smartphone colorimetric methods. Reproducibility was calculated from the detection of H2O2 at 25.0 and 50.0 nmol L−1 with the highest standard deviations of 3.47 and 4.58%, respectively. Additionally, the determination of all analytes in human urine samples indicated recoveries in the range of 96–104% with the highest relative standard deviation of 3.98%, offering high accuracy and precision. Our research shows the novel compatibility of basic technology and chemical methodology with green chemistry principles by reducing a high-power process and organic solvent as well as exhibiting good colorimetric performance and effective sensitivity and selectivity. Thus, our developed method can be applied for point-of-care medical diagnosis.

In this work, we developed the first ultrasound technique enhanced smartphone application for highly sensitive determination of hydrogen peroxide (H2O2).  相似文献   
960.
BackgroundMost patients undergoing caesarean delivery with general anaesthesia require systemic opioid administration. Due to its rapid onset and long duration of action, intravenous methadone may make it suitable for analgesia after caesarean delivery. Intraoperative methadone combined with postoperative intravenous patient-controlled analgesia with fentanyl or morphine has recently been introduced in our unit.MethodsA retrospective case-control study of 25 patients who had received methadone was performed. Fifty control patients undergoing elective or emergency caesarean delivery were matched for the use of postoperative intravenous patient-controlled analgesia, transversus abdominis plane (TAP) block and regular non-steroidal anti-inflammatory drugs. Exclusion criteria included preoperative neuraxial analgesia or pre-delivery opioid consumption greater than 10 mg of intravenous morphine equivalents.ResultsPatients in the methadone group had lower pain scores and were less likely to require intravenous opioid supplementation in the post-anaesthetic care unit (P < 0.001). Opioid consumption over 48 h was significantly lower in the methadone group. Delayed discharge from the post-anaesthesia care unit was due to sedation in one patient in the methadone group compared to three control patients in whom it was due to sedation and inadequate analgesia.ConclusionA single intraoperative bolus of intravenous methadone appeared to provide effective analgesia with an acceptable side-effect profile.  相似文献   
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