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71.
Wide local excision offers a potential cure for severe axillary hidradenitis suppurativa. However, the gold standard for reconstruction has yet to be defined. Here, we describe our rotation advancement flap technique, which allows for one‐stage closure of large axillary defects, with minimal functional morbidity to the axilla. We performed a retrospective review of all patients who underwent one‐stage surgical management for axillary hidradenitis suppurativa at a single‐centre tertiary care hospital from 2009 to 2018. We identified 34 patients, with a total of 53 operative sites. The majority were female (85%) with a mean age of 31 years and body mass index 35 kg/m2. The median defect size was 84 cm2 and the majority were treated using the rotation advancement flap technique (86%). A quarter of operative sites experienced minor complications with only one requiring re‐operation. At a median follow‐up of 32 months, two (4%) sites showed decreased range of motion. However, all patients had achieved remission without any further recurrence of disease. We describe a one‐stage rotation advancement flap technique for management of moderate to severe hidradenitis suppurativa that achieves a high local cure rate, minimal functional morbidity, and acceptable wound complication rates.  相似文献   
72.
E Pothos  P Rada  G P Mark  B G Hoebel 《Brain research》1991,566(1-2):348-350
This study shows the effect of opiate withdrawal on dopamine (DA) in the nucleus accumbens (NAC). Microdialysis was used to detect variations in extracellular DA, dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the NAC of freely moving rats during acute and chronic morphine treatment followed by naloxone-precipitated withdrawal with and without clonidine. Basal levels of extracellular DA did not change between sessions, but morphine (20 mg/kg, i.p.) caused a significant and identical increase in extracellular DA and metabolites in both the acute phase (day 1) and the chronic phase (day 7). On day 8, naloxone (20 mg/kg i.p.) caused a significant decrease in DA levels accompanied by typical withdrawal symptoms such as wet dog shakes and teeth-chattering. Clonidine pretreatment (200 micrograms/kg, i.p.) eliminated both the withdrawal symptoms and the DA decrease. These results support the view that morphine increases extracellular DA at times when the drug is rewarding and also suggest that the converse may be true; morphine withdrawal decreases DA release in association with the aversive state.  相似文献   
73.
Interleukin (IL-1) is a cytokine which plays an important role in the modulation of the acute in host defense. This cytokine is also increased in patients with Alzheimer's disease. In the present experiment systemic injection of IL-1β (7.5–50 μg/kg) decreased extracellular acetylccholine in the hippocampus. This effect could not be attributed entirely to general malaise since lithium chloride (130 mg/kg) had the opposite effect. Heat-inactivation of the cytokine eliminated the reduction of extracellular ACh. The results give further evidence of a relationship between the immune system and the central nervous system and suggest a possible relationship between IL-1 and cholinergic function or dysfunction in the hippocampus.  相似文献   
74.
75.
PURPOSE Many new mothers return to work soon after childbirth. This study examines personal and work-related factors associated with the postpartum health of employed women 11 weeks after childbirth.METHODS Using a prospective cohort design, we recruited 817 Minnesota mothers into the study while they were hospitalized for childbirth in 2001. Telephone interviews were conducted at 5 and 11 weeks postpartum. Eligible women were 18 years or older, employed, and spoke English and gave birth to a singleton infant. Multivariate models using instrumental variables (2-stage least squares) were used to estimate personal and employment characteristics associated with women’s physical and mental health and postpartum symptoms.RESULTS At 11 weeks postpartum, 661 participants (81% of enrollees) completed a full interview, and 50% of participants had returned to work. On average, women reported 4.1 (SD 3.2) childbirth-related symptoms, most frequently fatigue (43%). Factors significantly associated with better health outcomes included better preconception health, the absence of prenatal mood problems, more control over work and home activities, more social support at work and home, and less job stress.CONCLUSIONS The findings suggest postpartum women need to be evaluated regarding their fatigue levels and mental and physical symptoms. Women whose fatigue or postpartum symptoms limit daily role function may find it helpful to have health care clinicians counsel them on strategies to decrease job stress, increase social support at work and home, and certify their use of intermittent family and medical leave to help them manage their symptoms.  相似文献   
76.
To test the hypothesis that inaccurate DNA synthesis by mammalian DNA polymerase eta (pol eta) contributes to somatic hypermutation (SHM) of Ig genes, we measured the error specificity of mouse pol eta during synthesis of each strand of a mouse Ig kappa light chain transgene. We then compared the results to the base substitution specificity of SHM of this same gene in the mouse. The in vitro and in vivo base substitution spectra shared a number of common features. A highly significant correlation was observed for overall substitutions at A-T pairs but not for substitutions at G-C pairs. Sixteen mutational hotspots at A-T pairs observed in vivo were also found in spectra generated by mouse pol eta in vitro. The correlation was strongest for errors made by pol eta during synthesis of the non-transcribed strand, but it was also observed for synthesis of the transcribed strand. These facts, and the distribution of substitutions generated in vivo, support the hypothesis that pol eta contributes to SHM of Ig genes at A-T pairs via short patches of low fidelity DNA synthesis of both strands, but with a preference for the non-transcribed strand.  相似文献   
77.
Fatigue initiation and the propagation of microcracks in a cortical bone is an initial phase of damage development that may ultimately lead to the formation of macroscopic fractures and failure of the bone. In this work, a time-resolved high-resolution X-ray micro-computed tomography (CT) was performed to investigate the system of microcracks in a bone sample loaded by a simulated gait cycle. A low-cycle (1000 cycles) fatigue loading in compression with a 900 N peak amplitude and a 0.4 Hz frequency simulating the slow walk for the initialization of the internal damage of the bone was used. An in-house developed laboratory X-ray micro-CT imaging system coupled with a compact loading device were employed for the in situ uni-axial fatigue experiments reaching a 2μm effective voxel size. To reach a comparable quality of the reconstructed 3D images with the SEM microscopy, projection-level corrections and focal spot drift correction were performed prior to the digital volume correlation and evaluation using differential tomography for the identification of the individual microcracks in the microstructure. The microcracks in the intact bone, the crack formation after loading, and the changes in the topology of the microcracks were identified on a volumetric basis in the microstructure of the bone.  相似文献   
78.
A new case of pulmonary torsion is reported. Only 15 cases of this rare entity have been published in the literature, all of them either surgically treated short term or resulting in death. Small right-side pneumothorax following diagnostic transthoracic puncture seemed to be the mechanism of production. Because of the absence of acute clinical manifestations, fibroscopy, isotopic perfusion scanning, and hemodynamic and pulmonary angiographic studies were done. The lack of compromise in the pulmonary flow and venous pulmonary return explains the surprisingly good progress (ten months, at present) of the patient.  相似文献   
79.
Doppler hemodynamic study in portal hypertension and hepatic encephalopathy   总被引:2,自引:0,他引:2  
BACKGROUND/AIMS: The aim of our study was to evaluate and compare the differences in the parameters of portal hypertension in two groups of patients with liver cirrhosis, with and without hepatic encephalopathy (HE). METHODOLOGY: 30 patients with liver cirrhosis, 17 (56.7%) of them with HE, were investigated by clinical, neurological, laboratory, endoscopic methods and with color Doppler ultrasonography (CDU) at the Institute for Digestive Diseases, Clinical Center of Serbia, Beograde. RESULTS: Significant correlation was found between the diameters of the right liver lobe and the portal vein (p=0.01), and also between the diameters of the spleen and splenic vein (p=0.0002), in both groups of patients. Mean portal vein diameter significantly increases (p=0.01) in patients with HE (14.87 +/- 1.86mm), compared to those without HE (13.2 +/- 2.31mm), while mean splenic vein diameter was not significantly different in the two groups. In patients with ascites, CDU showed significantly lower (p=0.03) portal flow velocity (11.87 +/- 6.25cm/ sec), compared to those without ascites (14.33 +/- 4.41cm/sec). Splenic flow velocity was not significantly different (16.00 +/- 6.60cm/sec with ascites and 14.61 +/- 5.29cm/sec without ascites). In patients with HE, portal flow velocity was significantly lower (9.00 +/- 5.41cm/sec) compared to those without HE (14.0 +/- 7.03cm/sec) (p=0.04). Mean splenic flow velocity was significantly lower (p=0.03) in patients with HE (12.60 +/- 4.16cm/sec), compared to those without HE (17.77 +/- 5.91cm/sec). Portal flow velocity shows linear decrease, related to the increase of the liver damage (Child-Pugh score), while splenic velocity was not related to this parameter. CONCLUSIONS: Ultrasonographic parameters of portal hypertension show significant correlation between the diameters of liver/portal vein and spleen/splenic vein. Portal hemodynamic parameter (blood flow velocity) is significantly related to the stages of liver damage, presence of ascites and HE, while splenic hemodynamics is specific and not directly related to these parameters.  相似文献   
80.
Biochar is a versatile carbon-rich organic material originating from pyrolyzed biomass residues that possess the potential to stabilize organic carbon in the soil, improve soil fertility and water retention, and enhance plant growth. For the utilization of biochar as a soil conditioner, the mutual interconnection of the physicochemical properties of biochar with the production conditions used during the pyrolysis (temperature, heating rate, residence time) and the role of the origin of used biomass seem to be crucial. The aim of the research was focused on a comparison of the properties of biochar samples (originated from oat brans, mixed woodcut, corn residues and commercial compost) produced at different temperatures (400–700 °C) and different residence times (10 and 60 min). The results indicated similar structural features of produced biochar samples; nevertheless, the original biomass showed differences in physicochemical properties. The morphological and structural analysis showed well-developed aromatic porous structures for biochar samples originated from oat brans, mixed woodcut and corn residues. The higher pyrolysis temperature resulted in lower yields; however, it provided products with higher content of organic carbon and a more developed surface area. The lignocellulose biomass with higher contents of lignin is an attractive feedstock material for the production of biochar with potential agricultural applications.  相似文献   
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