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211.
Copper intrauterine contraceptive devices (Cu-IUD) are known to have more increased contraceptive effect and less complications that inert IUD. It has previously been shown that progesterone receptor binding is more affected by copper ions and the presence of copper in rabbit uterus results in less sensitivity to progesterone. It was expected that in a human wearer of Cu-IUD, the Cu induced changes of the endometrium in the secretory phase will be more obvious than in the proliferative phase. In this study the histological endometrial dating was compared with the dating by the basal body temperature. In the proliferative phase, 2 cases in 8 had the delayed and advanced datings respectively. In the secretory phase, 7 cases in 18 had the delayed dating and 1 case in 18 had the advanced dating. These results indicate that the proliferative endometrium (estrogen effect) is not affected but the secretory endometrium (progesterone effect) is affected by Cu-IUD, possibly resulting in the luteal insufficiency. (Author's)  相似文献   
212.
Using the polymerase chain reaction and single-strand conformation polymorphism analysis, p53 gene mutations were examined in 24 cases of ovarian tumor including 14 ovarian carcinomas and 2 borderline cases of common epithelial type, 7 germ cell tumors, and one stromal tumor. Abnormal bands indicating mutations were detected in 12 (50%) of the cases examined, being present most frequently in common "epithelial" ovarian carcinoma (71%, 10/14). One case each of squamous cell carcinoma originating in a dermoid cyst and anaplastic dysgerminoma were positive for mutation. Direct sequencing confirmed 12 mutations and revealed G-->A and G-->C nucleotide changes in 5 and 3 cases (42% and 25%), respectively. The mutation was localized at the CpG site of the gene in 3 cases. Immunohistochemical examination of p53 protein in 21 cases and DNA flow-cytometrical analysis in 17 cases were also performed. Nuclear accumulation of the p53 protein and DNA aneuploidy pattern were detected in 11 (52%) and 9 (53%) cases, respectively. These were significantly correlated with p53 gene mutation (P < 0.01 and P < 0.05, respectively; Fisher's exact test). Neither mutation of the p53 gene, nuclear accumulation of p53 protein nor DNA aneuploidy was detected in borderline cases of common "epithelial" type, typical dysgerminoma and immature teratoma. These results suggest that p53 gene mutation, nuclear accumulation of the protein and the DNA aneuploidy pattern are events occurring almost simultaneously in the progression of ovarian tumors, and that p53 abnormalities seem to be correlated with a high grade of malignancy.  相似文献   
213.
Predictions of diseases require suitable laboratory tests, mathematical methods for analyzing data and true normal ranges. Normal ranges are to be defined as 95% range of test results obtained on healthy subjects. "Healthy" subjects here refers to the persons who are free of the particular disease now and previously. However, to confirm the disease-free condition, laboratory test result must be evaluated on the basis of a normal range. This is a dilemma. The only way to overcome this problem is to follow a cohort for 10 or 20 years. Some of the "healthy" subjects will be suffering from diseases, while the others will still remain free of disease. That the latter persons would be the truly "healthy" subjects. Therefore, by their laboratory data and/or specimens such as serum every year we can determine the differences between the laboratory data of the patients and the true healthy subjects. In this respect, the development of laboratory database systems and serum banks are essential. We report a mathematical method for selecting significant data items for such a database and decision-making.  相似文献   
214.
A synchronous pulsatile venoarterial device for extracorporeal membrane oxygenation (ECMO) was designed to accomplish more effective circulatory support for neonates. The effect of this device was studied using an endotoxin-induced shock model, compared with conventional nonpulsatile ECMO. Twenty puppies weighing 1.6 to 4.0 kg were given endotoxin (5 mg/kg) intravenously. Thirty minutes after the administration of endotoxin, 10 were placed on pulsatile ECMO, and the others were placed on nonpulsatile ECMO, and they were studied for an additional 180 min. Peak blood pressure, arterial pH, base excess, and renal blood flow were significantly higher in the pulsatile group than in the nonpulsatile group. Serum lactate and serum noradrenaline were significantly lower in the pulsatile group than in the nonpulsatile group. These results indicate that pulsatile ECMO may provide more effective cardiopulmonary support in the treatment of neonates with serious circulatory failure that has failed to be supported by nonpulsatile ECMO.  相似文献   
215.
216.
Functional magnetic resonance imaging (fMRI) was used to examine whether preattentive and attentive visual processing, the cognitive psychological dichotomy on normal vision, indeed activate the parieto-occipital systems differentially as suggested by recent neuropsychological research. The activation paradigms consisted of feature detection and discrimination of line orientation, and visual fixation, which corresponded to preattentive, attention-requiring, and baseline conditions, respectively. The detection versus fixation contrast revealed activation sites in the right lateral prefrontal cortex and bilateral occipital lobes, whereas the discrimination versus fixation contrast showed broader bilateral activations extending from the occipital lobes through the parietal lobes, prefrontal cortex, thalamus, basal ganglia and upper brainstem. In the discrimination versus detection contrast, significant activations were observed in the right superior and inferior parietal lobules as well as in the subcortical structures. These findings were consistently demonstrated both at intra- and inter-subject levels. The present study provides further evidence to delineate neural substrate for the two distinct modes of visual processing and helps us to understand the neuropsychological mechanism underlying visual attention disorders.  相似文献   
217.
Psychological effects of aromatherapy on chronic hemodialysis patients   总被引:2,自引:0,他引:2  
Effects of aromatherapy (odorless condition, lavender, and hiba oil) on mood and anxiety were investigated in 14 female patients who were being treated with chronic hemodialysis. A control period consisting of natural hospital smells was established before each test session, and then aromatic test conditions were systematically evaluated for odorless conditions as well as aromatic conditions containing lavender and hiba oil aromas. The effects of aromatherapy were measured using the Hamilton rating scale for depression (HAMD) and the Hamilton rating scale for anxiety (HAMA). Hiba oil aroma significantly decreased the mean scores of HAMD and HAMA, and lavender aroma significantly decreased the mean scores of HAMA. The mean scores of HAMD and HAMA in an odorless condition were not significantly different from those of the control conditions. These results indicate that in chronic hemodialysis patients hiba oil is an effective, non-invasive means for the treatment of depression and anxiety, and that lavender alleviates anxiety.  相似文献   
218.
Thermological study of drilling bone tissue with a high-speed drill   总被引:3,自引:0,他引:3  
OBJECTIVE: To perform a detailed quantitative analysis of the effect of intermittent drilling and irrigation to lower the temperature during high-speed drilling. METHODS: We examined the thermal changes for 15 bone flaps while drilling a 7- x 7-mm area for 18 seconds and a specific point for 9 seconds, under the following conditions: continuous or intermittent drilling; with a fluted steel or a diamond ball cutter; without or with irrigation, with room temperature or cold (8 degrees C) Ringer solution. RESULTS: The maximum temperature during continuous drilling with a diamond cutter (or steel cutter) was 82.4 +/- 1.3 degrees C (55.2 +/- 1.0 degrees C) without irrigation, 42.5 +/- 1.2 degrees C (35.4 +/- 0.9 degrees C) with room temperature Ringer irrigation, and 22.5 +/- 1.4 degrees C (21.6 +/- 0.3 degrees C) with cold Ringer irrigation, whereas that during intermittent drilling was 66.1 +/- 1.2 degrees C (35.6 +/- 0.8 degrees C), 35.0 +/- 0.8 degrees C (25.4 +/- 0.7 degrees C), and 21.5 +/- 0.6 degrees C (21.8 +/- 0.4 degrees C), respectively. During continuous drilling of a specific point, the radius of the concentric isothermal line for 43 degrees C (thermal threshold for neurons) was 3.6 +/- 0.8 mm with a steel cutter, and it was 8.1 +/- 0.3 mm with a diamond cutter. The radius was 4.2 +/- 0.8 mm during intermittent drilling with a diamond cutter, and it was 4.0 +/- 0.1 mm during continuous drilling with room temperature Ringer irrigation. Intermittent drilling with cold Ringer irrigation kept the temperature, even at the center of the drilled area, below 20 degrees C. CONCLUSION: Intentional intermittent drilling with irrigation reduces temperature elevation and its expansion. These procedures are necessary for safe drilling, especially with a diamond burr. Although cold irrigation can minimize temperature elevation, its substantial effect on nerves or other structures needs to be elucidated.  相似文献   
219.
What we have learned from the Tokyo subway sarin gas attack on March 20, 1995, and the Wakayama poisoned curry incident on July 25, 1998, is that Japanese system for the analysis of drugs and poisons for medical treatment is extremely poor. The frequent occurrence of crimes involving drugs and poisons has become a serious problem. In response, the government established the Countermeasure Committee for Poisonous and Dangerous Substances, which submitted a report in November 1998. Based on that report, the Ministry of Health and Welfare equipped emergency medical centers with expensive analytical instruments, such as high-performance liquid chromatography columns and fluorescence X-ray analyzers, upon request. However, problems in their operation have occurred, and few such facilities work efficiently. In the Wakayama incident, the initial was food poisoning. Only after 11 hours and the deaths of four people was the diagnosis of cyanide poisoning made public. During that process, at least three mistakes were made. We believe that a basic and correct understanding of those mistakes and the development of countermeasures are necessary to analyze drugs and poisons from a medical standpoint.  相似文献   
220.
Abstract A developing child, with a high metabolic rate and low body stores of nutrients, is susceptible to metabolic disturbances due to surgical stress. For perioperative nutritional care of infants, the distinct physiologic features of their body fluids must be carefully considered. The postoperative metabolic response is the same as that in adults, but in children this response is more rapid. Based on the urinary excretion of 3-methylhistidine in infants, the postoperative degradation of muscle protein is thought to be twice the preoperative level. This transient increase during the early postoperative period was not suppressed by increased amino acid intake, and energy intake was sufficient. To prevent postoperative metabolic complications, the energy intake of glucose or fat should correspond to the patient—s requirements, and excess carbohydrate should be avoided. The quantity and quality of the amino acid formula used must be carefully evaluated. E-pub: 31 October 2000  相似文献   
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