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961.

Objective

To quantify maternal, fetal and neonatal mortality in low- and middle-income countries, to identify when deaths occur and to identify relationships between maternal deaths and stillbirths and neonatal deaths.

Methods

A prospective study of pregnancy outcomes was performed in 106 communities at seven sites in Argentina, Guatemala, India, Kenya, Pakistan and Zambia. Pregnant women were enrolled and followed until six weeks postpartum.

Findings

Between 2010 and 2012, 214 070 of 220 235 enrolled women (97.2%) completed follow-up. The maternal mortality ratio was 168 per 100 000 live births, ranging from 69 per 100 000 in Argentina to 316 per 100 000 in Pakistan. Overall, 29% (98/336) of maternal deaths occurred around the time of delivery: most were attributed to haemorrhage (86/336), pre-eclampsia or eclampsia (55/336) or sepsis (39/336). Around 70% (4349/6213) of stillbirths were probably intrapartum; 34% (1804/5230) of neonates died on the day of delivery and 14% (755/5230) died the day after. Stillbirths were more common in women who died than in those alive six weeks postpartum (risk ratio, RR: 9.48; 95% confidence interval, CI: 7.97–11.27), as were perinatal deaths (RR: 4.30; 95% CI: 3.26–5.67) and 7-day (RR: 3.94; 95% CI: 2.74–5.65) and 28-day neonatal deaths (RR: 7.36; 95% CI: 5.54–9.77).

Conclusion

Most maternal, fetal and neonatal deaths occurred at or around delivery and were attributed to preventable causes. Maternal death increased the risk of perinatal and neonatal death. Improving obstetric and neonatal care around the time of birth offers the greatest chance of reducing mortality.  相似文献   
962.
963.
The aim of this study was to explore the feasibility of determining parameters of cardiovascular function in mice noninvasively by high-temporal-resolution imaging with a dedicated small-animal PET system. METHODS: Twenty-five anesthetized mice (28.8 +/- 4.6 g) were injected via an intravenous catheter with a 30-microL bolus of (18)F-FDG (8-44 MBq). The first 9 s of data were reconstructed into 30 frames of 0.3 s using filtered backprojection. The time-activity curve derived from a left ventricle volume of interest was corrected for tracer recirculation and partial volume. Cardiac output was calculated by the Stewart-Hamilton method, in which cardiac output is total injected activity divided by the area under the left ventricle time-activity curve. Cardiac output divided by body weight was defined as cardiac index; cardiac output divided by heart rate yielded the stroke volume. In 5 mice, measurements were repeated 2-4 times to assess reproducibility. In 4 mice, the hemodynamic response to dobutamine was examined by measuring heart rate, cardiac output, and stroke volume. RESULTS: The cardiac output averaged 20.4 +/- 3.4 mL/min; in the repeated measurements, the parameter displayed a mean percentage SD per mouse of 10% +/- 6%. The cardiac index averaged 0.73 +/- 0.19 mL/min/g and the stroke volume 45.0 +/- 6.9 microL, and both correlated with heart rate (r = 0.53, P = 0.007, and r = 0.49, P = 0.01, respectively). During dobutamine stress, heart rate increased from 423 +/- 50 to 603 +/- 30 beats/min (P = 0.002) and cardiac output increased from 18.5 +/- 1.9 to 32.0 +/- 4.2 mL/min (P = 0.008). CONCLUSION: Parameters of cardiovascular function can be measured in mice noninvasively by radionuclide angiography using high-temporal-resolution small-animal PET. Measured values of cardiac output and stroke volume are reproducible and comparable to those obtained with MRI. The approach permits the monitoring of changes in cardiovascular function in response to pharmacologic intervention.  相似文献   
964.
Background A perineal hernia is a very rare clinical finding. Three forms are distinguished: anterior, posterior, and central. Diagnosis of the last one is difficult, and sometimes, it is falsely named a posterior rectocele. Aim This work presents a successfully treated case of central perineal hernia and makes a brief summary of existent literature on the problem. Presentation of the case We report of a 67-year-old female patient with a symptomatic central pelvic floor hernia. After radiological confirmation of the diagnosis, a transperitoneal approach was chosen to reposition the protruded segment of the small bowel. The hernial orifice was closed by extraperitoneal implantation of a polypropylene mesh. Discussion In the present case, the use of a laparoscopic technique seemed unsuitable due to the extension of the findings. For the repair of perineal hernia, we followed the principles of the “tension-free” concept. If there are no signs of a pelvic floor infection and if the mesh can be implanted totally extraperitoneally, we recommend the use of nonabsorbable alloplastic material (polypropylene) for reinforcement of the pelvic floor as a suitable technique for the repair of large perineal hernias.  相似文献   
965.
The amount of steel chips generated by lathes and CNC machines is 1200 million tons per year, and they are difficult to recycle. The effect of adding steel chips without pre-cleaning (covered with production lubricants and cooling oils) on the properties of concrete was investigated. Steel waste was added as a replacement for fine aggregate in the amounts of 5%, 10% and 15% of the cement weight, which correspond with 1.1%, 2.2% and 3.3% mass of all ingredients and 0.33%, 0.66% and 0.99% volume of concrete mix, respectively. The slump cone, air content, pH value, density, compressive strength, tensile strength, tensile splitting strength, elastic modulus, Poisson’s ratio and thermal parameters were tested. It was observed that with the addition of lathe waste, the density decreased, but mechanical properties increased. With the addition of 5%, 10% and 15% metal chips, compressive strength increased by 13.9%, 20.8% and 36.3% respectively compared to plain concrete; flexural strength by 7.1%, 12.7% and 18.2%; and tensile splitting strength by 4.2%, 33.2% and 38.4%. Moreover, it was determined that with addition of steel chips, thermal diffusivity was reduced and specific heat capacity increased. With the addition of 15% metal chips, thermal diffusivity was 25.2% lower than in the reference sample, while specific heat was 23.0% higher. No effect was observed on thermal conductivity.  相似文献   
966.
967.
OBJECTIVE: To test the hemodynamic efficacy and feasibility of nitric oxide (NO) administration by oxygen hood in neonatal pulmonary hypertension. STUDY DESIGN: A double-hood apparatus was used in which a combination of NO, O(2), and N(2) was introduced into the inner hood and suctioned from the outer hood. Chronically instrumented non-intubated piglets were exposed to 10% O(2) (hypoxia; n=8) or group B streptococci infusion (GBS; n=5) to produce pulmonary hypertension and were then exposed to 20 ppm NO. RESULTS: NO decreased (>50%) pulmonary artery pressure and vascular resistance in both hypoxia- and GBS-induced pulmonary hypertension, with minimal effects on systemic arterial pressure and cardiac output. NO administration could be performed without detectable environmental leakage. CONCLUSION: Hood NO administration is feasible and shows hemodynamic efficacy in neonatal piglets with pulmonary hypertension.  相似文献   
968.
Annamycin (Ann) is a non-cross-resistant lipophilic anthracy-cline antibiotic optimally suited for liposome delivery. We studied how vesicle size and presence of phospholipids with a high phase transition temperature and monosialoganglioside (GM1) in the liposome bilayers affect the pharmacokinetics, tumor selectivity and toxicity of Ann. Entrapment of Ann in multilamellar vesicles (L-Ann) resulted in a 20% lower heart AUC and a 30–40% higher tumor and liver AUC. Reduction of the liposome size from 1.6 to 0.03 μm increased Ann plasma circulation time and tumor AUC by 2-fold, enhanced Ann tumor selectivity and decreased Ann subacute toxicity by 2-fold. The presence of phospholipids with a high phase transition temperature and GM1 in the liposome bilayers further prolonged Ann plasma circulation time by 2- to 4-fold, did not increase Ann tumor AUC and moderately increased Ann subacute toxicity. The anti-tumor activity of Ann correlated with the tumor AUC achieved with each particular formulation. Our results strongly suggest that vesicle size may be an important determinant of the therapeutic index of liposomal Ann, but they fail to demonstrate a beneficial tumor-targeting effect of liposomes composed of GM1 and phospholipids with a high phase transition temperature, as has been reported for the hydrophilic parent compound doxorubicin. © 1995 Wiley-Liss, Inc.  相似文献   
969.
99mTc-d,l-HMPAO and SPECT of the brain in normal aging   总被引:2,自引:0,他引:2  
Single photon emission computed tomography (SPECT) with 99mTc-d,l-hexamethylpropyleneamine oxime (99mTc-d,l-HMPAO) was used to determine global and regional CBF in 53 healthy subjects aged 21-83 years. For the whole group, global CBF normalized to the cerebellum was 86.4% +/- 8.4 (SD). The contribution of age, sex, and atrophy to variations in global CBF was studied using stepwise multiple regression analysis. There was a significant negative correlation of global CBF with subjective ratings of cortical atrophy, but not with ratings of ventricular size, Evans ratio, sex, or age. In a subgroup of 33 subjects, in whom volumetric measurements of atrophy were performed, cortical atrophy was the only significant determinant for global CBF, accounting for 27% of its variance. Mean global CBF as measured with the 133Xe inhalation technique and SPECT was 54 +/- 9 ml/100 g/min and did not correlate significantly with age. There was a preferential decline of CBF in the frontal cortex with advancing age. The side-to-side asymmetry of several regions of interest increased with age. A method was described for estimation of subcortical CBF, which decreased with advancing cortical atrophy. The relative area of the subcortical low-flow region increased with age. These results are useful in distinguishing the effects of age and simple atrophy from disease effects, when the 99mTc-d,l-HMPAO method is used.  相似文献   
970.
Responses evoked byl-cysteine-sulphinate (l-CSA) andl-aspartate (l-Asp) were recorded with intracellular electrodes from caudate neurons in halothane anesthetized cats.l-CSA andl-Asp were applied microiontophoretically to caudate cells and their effects on membrane and action potentials, as well as on cortically evoked synaptic potentials were evaluated.l-CSA andl-Asp induced depolarizations accompanied by regular firing resembling kainate (KA)- or quisqualate (QUIS)-induced excitation patterns (type 1) in 82% and 72% of the recorded neurons, respectively, and a mixed pattern consisting of aN-methyl-d-aspartate (NMDA)-like excitation (type 2) followed by a regular type 1 pattern in the remaining cells. In about a quarter of the cells the effects ofl-CSA andl-Asp, but not those of KA or QUIS, were partially antagonized by 2-amino-7-phosphonoheptanoate (AP-7), a specific NMDA receptor antagonist. Kynurenate, a broad spectrum excitatory amino acid antagonist, blocked responses elicited by eitherl-CSA or QUIS. The actions ofl-CSA andl-Asp on the firing pattern and membrane potential of cat caudate neurons in situ provide evidence in favor of their mixed agonist nature with respect to NMDA and non-NMDA excitatory amino acid receptors.  相似文献   
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