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11.
Characterization of Leishmania species from Peru   总被引:1,自引:0,他引:1  
Twenty-six isolates of Leishmania parasites of Peruvian origin were studied by isoenzyme electrophoresis of four marker enzymes (ASAT, ALAT, G6PD and GPI), kinetoplast DNA hybridization and monoclonal antibody binding and compared with marker strains of the New World organisms L. b. braziliensis, L. b. guyanensis, L. m. mexicana and L. m. amazonensis. 12 of the isolates studied were of Andean origin; 11 of these were isolated from patients with Andean cutaneous leishmaniasis. The organisms originating from the Peruvian Amazonian forest were isolated from patients with cutaneous (12 cases) or mucocutaneous (2 cases) leishmaniasis. One of the Andean isolates was obtained from an infected phlebotomine vector. 25 of the new isolates were identified as L. braziliensis ssp. according to the three techniques employed. The results of monoclonal antibody binding showed that 23 of the isolates were indistinguishable from L. b. braziliensis. Two isolates identified as L. braziliensis ssp. according to their isoenzyme profiles and k-DNA hybridization patterns could not be classified at the subspecies level. The isolate obtained from the phlebotomine vector could not be identified. No evidence of the existence of parasites of the L. mexicana complex in Peruvian territory was found in this study. The results obtained show a remarkable similarity between Leishmania of Andean origin and L. b. braziliensis.  相似文献   
12.
To evaluate the incorporation of branched-chain amino-acids (BCAA) in de novo synthesised albumin, a series of experiments was performed with cultured hepatocytes from normal (Group 1) and stressed rats (groups 2 and 3). Stress was induced by keeping the rats immobilised in a cold room for 6–8 h and assessed by the presence of bleeding ulcers in the stomach.The cells were cultured in a commercial synthetic medium (Ham F-12) poor in BCAA (5.74% of total) increasing amounts of BCAA were added to plates in groups 1 and 2 and equivalent quantities of nitrogen in the form of glycine were added to plates in group 3.In group 1, the increase in BCAA concentration from 22.74–210.8 mg/ml was followed by an increase in the albumin synthesis rate from 0.4–0.95 ug/mg cell prot/h.In group 2, the rise in BCAA was followed by a far greater increase from 0.3–5 ug/mg cell prot/h (at least 6 times normal levels).In group 3, only 20% of the increase in albumin synthesis obtained in group 2 was observed. These results suggest that in stress the liver increases the use of BCAA for protein synthesis, but the increase of nitrogen in the culture medium respresents only a low percentage of this effect.  相似文献   
13.
The effect of chronic oral thyrotrophin-releasing hormone (TRH) administration on thyrotrophin (TSH), L-triiodothyronine (T3) and L-thyroxine (T4) serum levels, pituitary TSH concentration and serum response to acute TRH injection, has been studied in female rats under different thyroidal conditions: sham-operated control animals, and thyroidectomized animals receiving 25 micrograms L-T4/100 g body weight/day. After 30 days, these groups were divided into two subgroups (6-10 animals per group), one receiving the aforementioned treatment and the other the same plus 2 mg TRH/10 ml distilled water (DW), as drinking water. TRH-treated sham-operated animals showed significantly reduced serum and pituitary TSH levels and increased serum T3 levels at most of the times studied (1, 6, 10, 18 and 34 days of oral TRH or DW administration), and a transient elevation in serum T4 between day 1 and 6. Thyroidectomized-L-T4-treated animals showed increased serum and pituitary TSH levels throughout the treatment and reduced T3 and T4 serum levels at the beginning, as compared to thyroidectomized-L-T4-treated animals. TSH response to iv TRH administration on the 10th day of oral TRH administration was reduced in controls chronically treated with oral TRH as compared to non-treated controls, and was increased in thyroidectomized-L-T4-treated animals on chronic TRH vs the same group on oral DW. These results suggest that chronic TRH administration can stimulate TRH synthesis in vivo, bypassing the inhibitory effects of thyroid hormones, the increased pituitary TSH reserve being responsible for the partial restoration of a response to acute TRH injection in the thyroidectomized-L-T4-treated animals.  相似文献   
14.
Localised agenesis of the scalp is the most frequent patern in aplasia cutis congenita (ACC), a congenital absence of the skin and occasionally of deeper layers. Several clinical groups are characterised by the location and pattern of skin defects, associated malformations and the mode of inheritance. Death occurs in 20% of cases, secondary to the associated anomalies, to infections or to haemorrhage from ulceration of the sagittal sinus when there is also a defect of the underlying skull. In this latter case, we close the defect by two rotational scalp flaps (Orticochea technique) at birth. A three-dimensional CT study is useful for showing the extent of the skull defect and the deformity of the craniofacial complex and the changes in the bone after treatment.  相似文献   
15.
Living liver donation is becoming a more widely accepted practice given the decrease in donor morbidity and mortality and the beneficial results in the recipient. Use of this technique is unusual in Spain. There are a number of workers against its use within the health care system. The objective of this study was to analyze attitudes toward and the variables that affect them concerning living liver donation among surgical services in a transplant hospital. MATERIALS AND METHODS: A random survey was stratified by surgical area and job category in a Spanish third-level hospital with an ongoing solid organ transplant program. Attitudes toward living liver donation were assessed using a questionnaire about organ donation and transplantation that evaluated various psychosocial variables. Student's t test and the chi square test were used. RESULTS: A total of 263 workers were surveyed (mean age as 40 +/- 9 years). Regarding attitudes toward living liver donation, the level of acceptance was 80% (n = 211) of respondents, whereas 10% were undecided (n = 26), and another 10% were against (n = 26), assuming that the donations were related. When we asked about unrelated living donation, the percentage in favor decreased to 10% (n = 27). No differences were found with respect to job category or type of service. The variables that are related to such an attitude are the following: (1) possibility of respondent needing an organ (P = .001); (2) favorable attitude toward living kidney donation (P < .000); and (3) a belief that medical errors exist (P = .004). An important finding was that attitudes toward living liver donation were not more favorable according to whether the respondent was in favor or against cadaveric organ donation (P = .175). CONCLUSION: There was a highly favorable attitude toward living liver donation among hospital personnel in surgical services, which is an important factor to take into account if this type of donation is to be encouraged in Spain.  相似文献   
16.
OBJECTIVE: To analyse the need for operation for pyloric stenosis caused by duodenal ulcer over a period of 24 years (1976-1999). DESIGN: Retrospective study. SETTING: University hospital, Spain. SUBJECTS: 156 patients operated on for peptic pyloric stenosis. MAIN OUTCOME MEASURES: The number of patients operated on yearly were grouped into 4-year periods for statistical comparison. RESULTS: The number of cases operated on each year steadily decreased between 1976 and 1999. In the 1988-1991 period there was a significant reduction (p <0.05), which continued over the next two 4-year periods, particularly the last (p <0.01). CONCLUSION: Although we cannot use this study to establish a direct relation between the decrease in the indication for operations for peptic pyloric stenosis and the use of H2 antagonists, proton pump inhibitors, or treatment to eradicate Helicobacter pylori, we did find a significance difference between the years before and after the introduction of these drugs.  相似文献   
17.
OBJECTIVE: To compare the toughening effects in rats induced by pure tones and a broadband noise (BBN). MATERIAL AND METHODS: Sprague-Dawley female albino rats (n = 148; 8-10 weeks old) were used. Three experimental groups were established as follows. Toughening only: 38 rats, divided into 3 subgroups, were exposed to different conditioning sounds (2 and 4 kHz and a BBN of 0.25-6 kHz, respectively) at 75-85 dB sound pressure limit (SPL) for 8 h/day for 10 days. Acoustic trauma only: 54 rats, divided into 3 subgroups, were exposed to different conditioning sounds as above for 24 h at 100-110 dB SPL. Toughening plus acoustic trauma: 56 rats, divided into 3 subgroups, were exposed to different conditioning sounds as above, followed 8 h later by traumatic exposure to the conditioning sound at 110 dB SPL for 24 h. 2f1-f2 distortion-product (DP) otoacoustic emission measurements were obtained from the right ear of each animal pre-exposure, immediately post-exposure and after 8 h of the traumatic or conditioning exposure. RESULTS: In our control DPgram response, the maximum amplitude occurred at the highest frequencies (2, 3, 4, 5 and 6 kHz). No statistical differences between the control DPgram and the DP toughening (2 and 4 kHz and BBN)responses were found. Only 2 and 4 kHz frequencies induced a protective effect against traumatic sound exposures to the same frequencies, and this finding was statistically significant. CONCLUSION: The toughening phenomenon induced using 2 and 4 kHz pure tones and BBN in rats does not modify the DPgram response. Nevertheless, only 2 and 4 kHz frequencies induce a protective effect against traumatic sound exposures to the same frequencies.  相似文献   
18.
Petiveria alliacea is a plant traditionally known for its anti-inflammatory and anti-tumor activities; however, the molecular and cellular mechanisms of its immunomodulatory properties are still unknown. Dendritic cells (DC) promote adaptive immune response by activating T lymphocytes, inducing an effector response or tolerance depending on the DC differentiation level. Herein, we evaluated the immunomodulatory activity of aqueous and organic plant fractions from P. alliacea using human monocyte-derived dendritic cells. The phenotype, cytokine secretion and gene expression were estimated after treatment with the plant fractions. We found that P. alliacea aqueous fraction induced morphological changes and co-stimulatory expression of CD86, indicating partial DC maturation. In addition, pro-inflammatory cytokines such as IL-1β, IL-6, IL-8, IL-10, IL-12p70, and TNF-α were secreted. The fraction also increased NF-κB gene expression while down-regulating TGFβ gene expression. These results suggest that the aqueous fraction can induce partial DC activation, a situation that can be relevant in tolerance induction. It is important to state that the organic fraction by itself does not show any immunomodulatory activity. This study provides evidence for possible immunomodulatory activity of P. alliacea extracts which has been used in traditional medicine in Colombia.  相似文献   
19.
Ventricular aneurysm due to blunt chest injury   总被引:1,自引:0,他引:1  
A left ventricular aneurysm developed in 3 patients sustaining blunt chest injury. Evidence of an acute myocardial infarction on the electrocardiogram and enzyme analysis prompted cardiac catheterization, which revealed total occlusion of the left anterior descending coronary artery in 2 of the 3 patients. Ventricular aneurysmectomy was performed in each patient. A review of the literature revealed 32 previously reported patients with left ventricular aneurysm caused by blunt trauma. Clinical features, catheterization or autopsy findings, and outcome are examined.  相似文献   
20.
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