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81.
The need for a clinically applicable method of detecting splanchnic hypoxia has led to experimental animal studies which indicated the usefulness of intestinal pulse oximetry. Pulse oximetry relies on detection of photoplethysmographic signals. Before developing a pulse oximeter for the measurement of organ oxygen saturation peri-operatively, we designed a system based on a reflectance photoplethysmographic probe to investigate photoplethysmographic signals from human viscera (bowel, liver, and kidney). Recordings were obtained simultaneously from the abdominal viscera and the finger using identical probes. The probe was held sequentially for up to 2 min on the surface of viscera of 12 patients during routine laparotomy. Measurable splanchnic photoplethysmographic signals were recorded for the first time in humans. There were no statistically significant differences between photoplethysmographic amplitudes from viscera and those from the finger. Our results indicate the feasibility of pulse oximetry for the measurement of visceral oxygenation in humans. 相似文献
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83.
Primary ovarian pregnancy is a rare type of ectopic pregnancy, which is difficult to diagnose clinically and even intra operatively. Here we present a case of a 20-year-old woman with ruptured right ovarian pregnancy and dermoid cyst of left ovary. 相似文献
84.
Analysis of the patterns of stromal cell-derived factor 1alpha (SDF-1alpha) expression in the brains from HIV-positive patients suggests that in neuronal cells, SDF-1alpha might play a role in neuroprotection and neurite extension in response to HIV infection. In all cases analyzed, SDF-1alpha immunoreactivity was primarily present in astroglial cells. Patients with HIV encephalitis (HIVE) showed intense somato-dendritic neuronal SDF-1alpha immunoreactivity, while HIVE negative patients with neurodegeneration had a significant decrease in neuronal SDF-1alpha immunoreactivity. Neuronal cells treated with SDF-1alpha displayed increased neurite outgrowth. Similarly, neurons treated with HIV-Tat, which induced SDF-1alpha expression, also showed neurite outgrowth. Tat-mediated neurite outgrowth was blocked by anti-SDF-1alpha antibody. These results suggest that SDF-1alpha may play a role in the neuronal response to HIV in the brains of AIDS patients. 相似文献
85.
A. Langford R. Kunze S. Schmelzer H. Wolf H.-D. Pohle P. Reichart 《Journal of oral pathology & medicine》1992,21(2):49-57
Cytologic smears (CS) were taken from the lateral border of the tongue of HIV-seropositive patients (HIV+) (n = 39) and of seronegative controls (HIV-) (n = 19) and examined by immunocytochemistry (APAAP) and in situ hybridization (ISH) (biotinylated DNA probes) for the presence of viral antigens/DNA of EBV and CMV. While none of the HIV controls showed positive results for EBV antigen, 61% (APAAP) resp. 79% (ISH) of oral epithelial cells in the group of HIV+ patients were EBV-positive. While all CS taken from areas with the clinical diagnosis of hairy leukoplakia (HL) were EBV positive (APAAP and/or ISH), the detection of EBV in CS from uninvolved oral mucosa seemed to be associated with the later development of HL. In the group of HIV+ patients the detection rate for CMV was about five times (APAAP) resp. three times (ISH) higher than in HIV- persons. This non-invasive technique seems to be a valuable tool to screen for viral antigens/genomes. 相似文献
86.
Risk factors in onychocryptosis 总被引:3,自引:0,他引:3
A study is described in which the normal toes of 50 patients with unilateral ingrowing toenails were compared with those of 50 healthy subjects matched for age and sex. Twenty-one potential risk factors were compared between the groups. All measurements on patients were derived from unaffected toes in order to avoid anatomical distortion due to the disease process. Statistical analysis revealed significant differences between the groups for three anatomical measures, namely nail fold width (P less than 0.001), medial rotation (eversion) of the great toe (P less than 0.02) and nail thickness (P less than 0.03). Possible discriminating variables were assessed using linear discriminant function analysis and a mathematical equation was derived based on these three factors. This equation was found to possess a potentially high predictive value in that it correctly classified 86 per cent of the patients and 77 per cent of the controls. A further group of 62 unselected patients presenting with unilateral onychocryptosis and 35 unaffected controls were assessed for these three parameters. Of these, 80 per cent of controls and 85 per cent of patients could be classified correctly by the equation. It is thus proposed that, in the majority of subjects with onychocryptosis, a discrete anatomical predisposition exists and that the other factors act only as triggers in the development of the condition. This study provides a rationale for less traumatic surgical approaches to ingrown nail than nail avulsion, with or without nail bed ablation and may also provide a means of identifying high-risk groups. 相似文献
87.
88.
89.
Respiratory disease in calves produced with aerosols of parainfluenza-3 virus and Pasteurella haemolytica 总被引:6,自引:0,他引:6
In four experiments, 22 calves were exposed to aerosols of parainfluenza-3 virus, followed by Pasteurella haemolytica at intervals of three to 13 days. The purpose of each experiment was to study viral-bacterial interactions in the respiratory tracts. Two experiments, in which the viral aerosols were diluted by the addition of air, produced sporadic temperature elevations while two experiments with undiluted viral aerosols produced consistent temperature elevations. Diluted viral aerosols produced lobular sized lesions in the lungs and hemagglutinating inhibition antibodies in sera, whilst undiluted aerosols produced a synergistic effect in the form of purulent pneumonia in ten of 14 calves when the interval between viral and bacterial aerosols was from three to ten days. Histopathological changes attributable to the virus only were seen in all experiments, and the histopathological changes due to mixed infection of parainfluenza-3 virus and P. haemolytica are described in detail. This is the first report of extensive purulent pneumonia in calves after parainfluenza-3 virus and P. haemolytica exposure. This was achieved using much smaller inocula than in experiments previously reported. 相似文献
90.
The purpose of this study was to compare unilateral squat strength of the dominant and non-dominant leg in young adult men and women. Seventeen apparently healthy men (mean mass 90.5 ± 20.9 kg and age 21.7 ± 1.8 yrs) and 25 women (mean mass 62.2 ± 14.5 kg and age 21.9 ± 1.3 yrs) completed the study. To determine unilateral strength, the subjects completed a one repetition maximum (1RM) modified unilateral squat (MUS) on the dominant and non-dominant leg. The subjects completed the squat to a depth that attained a 90° angle at the knee. This exercise was executed by placing the top of the metatarsophalangeal area of the foot of the uninvolved leg on a support bar behind the subject to isolate the use of the lead leg. Paired samples t-test revealed no significant difference between the men’s 1RM mean strength on the dominant (107.0 ± 21.4 kg) and non-dominant (106.0 ± 21.4 kg) leg with a mean side-to-side difference (comparing the stronger to the weaker leg) of 2.8 %. Leg strength symmetry was also found between the women’s 1RM mean strength on the dominant (45.3 ± 12.5 kg) and non-dominant (45.0 ± 12.4 kg) leg with a mean side-to-side difference of 5.0 %. The data indicate that unilateral squat strength, measured in a weight bearing stance, is similar in the dominant and non-dominant leg in apparently healthy young adult men and women.
Key Points
- MUS strength was similar between the dominant and non-dominant leg in young adult men and women.
- Mean side-to-side differences (comparing the stronger to the weaker leg) resulted from higher dominant and non-dominant scores for the men and women
- The range of side-to-side differences warrants the practice of weight bearing strength assessment to identify those at risk for injury.