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71.
The concentrations of LH, FSH and PRL were determined in serum samples obtained at night in 1–2 h intervals as well as at 15 min intervals during a 3 h period between 9 and 12 p.m. and 9 and 12 a.m. in three girls with premature thelarche, who had not developed further signs of precocious puberty for more than 18 months.A sleep-dependent LH and FSH increase was documented in all of them with a predominance of FSH secretion during sleep and after LHRH stimulation. In all three girls an episodic pattern of LH was found during sleep. In daytime minor fluctuations of LH secretion were found in two patients whereas in one patient an episodic LH pattern was demonstrable with minor peak values as during sleep.Normal PRL secretion during sleep as well as after TRH stimulation excludes a permissive role of this hormone in premature thelarche.We conclude that in girls with isolated premature thelarche a matured hypothalamo-pituitary gonadotropin axis is active comparable to normal pubertal children.  相似文献   
72.
Trichilemmal cysts (also named pilar cyst) derived from the outer root sheath of the deeper parts of the hair follicle can segregate dominantly, and are caused by a yet unknown gene. In order to identify candidate genes for this trait we have ascertained a Danish family with 38 persons (11 affected), and carried out a genome wide scan with 580 DNA micro-satellite markers to identify the locus for a gene, which we termed TRICY1 (for trichilemmal cysts). We found tight linkage to D3S1277 (Z = 4.63; theta(M = F) = 0.00), with flanking markers D3S2432 (Z = 1.59; theta(M = F) = 0.08), and D3S3685 (Z = 2.69; theta(M = F) = 0.08) spanning 10.3 Mb on chromosome 3p24-p21.2. We sequenced two candidate genes previously reported in inherited hair defects, CTNNB1 and MLH1 but failed to detect mutations in exons and intron-exon bounders.  相似文献   
73.
The impact of invasive hemodynamic monitoring on patient safety and outcome in perioperative medicine remains inadequately tested and unproven. The indications for the use of these tools should, therefore, be evaluated according to an individual risk-benefit analysis. The measurement of central venous oxygen saturation (ScvO2) is of little invasiveness as most high-risk patients are instrumented with central venous catheters, and ScvO2 has been shown to improve outcome in patients with septic shock. Transpulmonary thermodilution (e.g. PiCCO-system) delivers information not only on global cardiac function and intravascular volume status but also helps to define the pulmonary consequences of cardiovascular therapy. Transesophageal echocardiography (TEE) is a valuable tool in patients undergoing cardiac surgery and represents the beside-method of choice for rapid assessment of acute life-threatening cardiovascular instability. Apart from special indications, these tools tend to replace the pulmonary artery catheter (PAC) which has been shown to be of little value in various patient populations.  相似文献   
74.
PURPOSE: This study analyzed the correlation between the compressive strength of human thoracolumbar vertebrae, bone density and endplate area (measured by SE-QCT). METHOD: The compressive strength of 110 human vertebral specimens (D11-L5) was measured. In order to determine standard values for human vertebral specimens from each level and different female and male age groups were examined. Before biomechanical testing the specimens were examined using SE-QCT with 1.5 and 10 mm slice thickness. Three different slice locations (mid-vertebral and adjacent to both endplates) and 6 regions of interest (ROI) were chosen to assess BMD. The area of the vertebral endplates was measured by CT. RESULTS: Highest correlations between BMD and compressive strength were found for the 10 mm thick midvertebral slices with a small ellipsoid ROI. Cancellous and cortical bone contributed to the compressive strength to the same amount. Compressive strength and endplate area increased in the cranio-caudal direction, bone density was constant throughout thoracolumbar spine. Bone density and compressive strength depended on age and sex. Compressive strength of human thoracolumbar vertebrae increased with bone density as well as the size of the endplates. CONCLUSIONS: Using bone density and endplate area (SE-QCT) of human thoracolumbar vertebrae (D11-L5) a prediction of compressive strength is possible with an error of estimation of 1.17 kN and a correlation factor of 0.85. The prediction of the compressive strength allows an estimation of the risk of vertebral fracture, i.e. in patients with osteoporosis or in individuals with intensive physical activities. The standard values of the human thoracolumbar vertebrae together with biomechanical examinations of vertebral metastases can be used to estimate the compressive strength of osteolytic and osteoplastic spinal metastases.  相似文献   
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76.
Local and peripheral immune responses are activated after ischemic stroke. In our present study, we investigated the temporal distribution, location, induction, and function of regulatory T cells (Tregs) and the possible involvement of microglia, macrophages, and dendritic cells after middle cerebral artery occlusion (MCAO). C57BL/6J and Foxp3EGFP transgenic mice were subjected to 30 minutes MCAO. On days 7, 14, and 30 after MCAO, Tregs and antigen presenting cells were analyzed using fluorescence activated cell sorting multicolor staining and immunohistochemistry. A strong accumulation of Tregs was observed on days 14 and 30 in the ischemic hemisphere accompanied by the elevated presence and activation of microglia. Dendritic cells and macrophages were found on each analyzed day. About 60% of Foxp3+ Tregs in ischemic hemispheres were positive for the proliferation marker Ki-67 on days 7 and 14 after MCAO. The transfer of naive CD4+ cells depleted of Foxp3+ Tregs into RAG1−/− mice 1 day before MCAO did not lead to a de novo generation of Tregs 14 days after surgery. After depletion of CD25+ Tregs, no changes regarding neurologic outcome were detected. The sustained presence of Tregs in the brain after MCAO indicates a long-lasting immunological alteration and involvement of brain cells in immunoregulatory mechanisms.  相似文献   
77.
Neurons were described in the visual Cortex of Microtus brandti, a Mongolian harmful rodent living in day-activity. We find following types of neurons in our Golgi-material: 1. spiny neurons: pyramidal and stellate neurons. 2. smooth or sparsely spined neurons: smooth, large neurons, sparsely spined small neurons with descending axons, sparsely spined neurons with ascending axons. Double-bouquet-, chandelier and neuroglioforme cells are not impregnated. There are no bipolare neurons (Martinotti cells) among the neurons with ascending axons. The small, sparsely spined neurons are not only in lamina IV - like in other species - but they can also be found in laminae II to IV. Their distribution of spines on the distal parts of dendrites seems to be characteristical for rodents. The lamination of the visual cortex of Microtus brandti is the same like in the rat. All cells are of large size in relation to the body mass of the animal.  相似文献   
78.
79.
The purpose of the present paper has been to examine the reproducibility of the classification of gastric carcinomas, as proposed by Mulligan and Rember. Two microscopic slides from each of one hundred randomly selected specimens of gastric carcinoma, obtained by gastrectomy or gastric resection, were classified independently by both authors. Neither of the authors knew which slides originated from the same specimen. The inter-examiner reproducibility rate was 79 per cent. The reproducibility rates of the diagnoses with two independent slides from the same tumour was 74 per cent with examiner I and 80 per cent with examiner II.  相似文献   
80.
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