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71.
Aim The aim of the study was to investigate neutrophil respiratory burst activity (NRBA) in workers who were occupationally exposed to formaldehyde.Methods NRBA, spontaneous and stimulated with E. coli, N-formyl-methionyl-leucyl-phenylalanine (fMLP) and phorbol 12-myristate 13-acetate (PMA), was studied by means of quantitative flow cytometric determination in 29 workers who were occupationally exposed to formaldehyde; 21 healthy subjects, not exposed to formaldehyde, served as controls. All subjects underwent clinical assessment, including a review of a summary of their medical history and a physical examination. Routine haematological tests were performed.Results A statistically significant predominance of subjective symptoms and objective clinical findings of chronic upper respiratory tract inflammation, as well as decreased resistance to infections, was observed in the 29 workers exposed to formaldehyde, compared with the controls (2=9.28, P=0.02). No statistically significant difference in the spontaneous and stimulated NRBA between the exposed workers and the control group was observed. The spontaneous NRBA (percentage oxidizing cells) was significantly lower in the group of exposed workers with upper respiratory tract findings and frequent and long-lasting infectious inflammatory relapses (median and range 0.45 (0.02–2.03), mean values 0.65±0.74) than in the healthy controls (median and range 1.35 (0.07–8.69), mean values 2.42±2.47; P<0.05), and in the group of exposed workers with rare and short, acute, inflammation of the upper respiratory tract or without any inflammations (median and range 1.00 (0.02–8.67), mean values 1.67±2.08; P<0.05). A significant negative correlation between the duration of occupational exposure to formaldehyde and erythrocyte count and haematocrit was found.Conclusions The observed decrease of spontaneous NRBA in workers with a history and clinical findings of frequent and long-lasting relapses of chronic inflammation of the upper respiratory tract could be due to formaldehyde exposure and individual susceptibility. The results obtained suggest that functional changes in polymorphonuclear neutrophil granulocytes could serve as an early indicator of an impact of formaldehyde on NRBA. The applied method might be used for identifying groups at increased toxicological risk.  相似文献   
72.
Morphological study of allotransplants of rat embryonic neocortex 14-18 months after transplantation into the neocortex, lateral cerebral ventricle, and sciatic nerve of adult animals revealed death of nerve and glial cells in the delayed postoperation period independently on the site of transplantation. After heterotopic transplantation the count of degenerated neurons was 2 times higher that after homotopic transplantation. In heterotopic transplants a considerable number of grafted neurons underwent reversible and irreversible degenerative changes accompanied by their premature aging. Neuronal death is probably determined by insufficiency of trophic influence from afferent structures and target tissues. We hypothesized that antiapoptotic preparations can be used for prevention of transplanted cell death. It was also found that degeneration of neurons was associated with impaired vascularization of transplants and pronounced immune reaction of the recipient in late posttransplantation period. Transplantation of embryonic brain structures can serve as a model system in studies concerning involutive and pathological processes in the central nervous system and in the search for factors improving survival of neurons.  相似文献   
73.
A total of 315 pregnant women were under observation: 290 (92.1%) of women with myopia made up the main group, and 25 (7.9%), which had no extragenital pathologies or any pregnancy complications, were in the control group. It was for the first time that an algorithm of pregnancy and delivery monitoring for myopic patients was worked out: the algorithm comprises ophthalmologic examinations including rheoophthalmography carried out during the delivery. The specific features of the ocular hemodynamics and intraocular pressure as well as their dependence on the parameters of central hemodynamics and volumetric cerebral blood velocity at all stages of spontaneous delivery were studied. The role of prolonged epidural anesthesia, as a method normalizing the hemodynamics of the ciliary tract, was defined to optimize the delivery by women with average and high myopia. The above stated makes it possible to prevent possible complications (in the organ of vision) in patients with average and high myopia and to decrease the frequency of operative delivery from 21.8% to 1.3%.  相似文献   
74.
Reconstruction of the urinary tract because of ureteral stricture after kidney transplantation is a serious problem. In development of obliteration of the recipient's ureter near anastomosis and in the absence of own ureters reconstruction is made by pyelocystoanastomosis. A case is reported of a successful use of this method in reconstruction of the urinary tract. Preoperative preparation includes transcutaneous nephrostomy. Sometimes Boary flap is used. The arising reflux had insignificant effect on the transplant's function.  相似文献   
75.
AIM: To analyse results of treatment of invasive aspergillesis in immunocompromised patients for 2000-2002. MATERIAL AND METHODS: The study was made of patients who, when treated with antibiotics, exhibited foci in the lungs typical for invasive aspergillesis. Aspergillas were detected in the sputum, bronchoalveolar lavage, bronchial wash-ups, aspergilla antigen (galactomannan) was detected in the blood. RESULTS: Invasive aspergillesis was diagnosed in 25 patients. 13 (52%) patients were treated with adjuvant glucocorticoids. 19 (76%) patients had neutropenia. All the patients had fever. Foci in the lungs were in 24 patients. Aspergillas were detected in 15 patients, a positive antigen galactomannan in 7 patients. A. Fumigatus, A flavus, A. Niger occurred in 67, 26.5 and 6.5% patients, respectively. All the patients received amphotericin B (median of the treatment reached 38 days, total dose 880-3500 mg). In 5 patients amphotericin B was replaced for liposomal amphotericin B because of high creatinine. 7 patients continued with itraconasol in a dose 400-600 mg/day. The foci were removed in 3 patients. The cure was achieved in 12 patients, 13 patients, 13 patients died (cause of death--respiratory insufficiency). CONCLUSION: Lethality in invasive aspergillesis in immunocompromised patients remains high--52%. Cultural detection of mycelial fungi was, as a rule, delayed. Early diagnosis of the disease requires monitoring of the aspergilla antigen in the blood and computer tomography of the chest especially in fever persisting in the treatment of wide-spectrum antibiotics.  相似文献   
76.
Substantial evidence supports a role for dysfunction of brain serotonergic (5-HT) systems in the pathogenesis of major affective disorder, both unipolar (recurrent major depression) and bipolar.(1) Modification of serotonergic neurotransmission is pivotally implicated in the mechanism of action of antidepressant drugs(2) and also in the action of mood stabilizing agents, particularly lithium carbonate.(3) Accordingly, genes that code for the multiple subtypes of serotonin receptors that have been cloned and are expressed in brain,(4) are strong candidates for a role in the genetic etiology of affective illness. We examined a structural variant of the serotonin 2C (5-HT2C) receptor gene (HTR2C) that gives rise to a cysteine to serine substitution in the N terminal extracellular domain of the receptor protein (cys23ser),(5) in 513 patients with recurrent major depression (MDD-R), 649 patients with bipolar (BP) affective disorder and 901 normal controls. The subjects were drawn from nine European countries participating in the European Collaborative Project on Affective Disorders. There was significant variation in the frequency of the HT2CR ser23 allele among the 10 population groups included in the sample (from 24.6% in Greek control subjects to 9.2% in Scots, chi(2) = 20.9, df 9, P = 0.01). Logistic regression analysis demonstrated that over and above this inter-population variability, there was a significant excess of HT2CR ser23 allele carriers in patients compared to normal controls that was demonstrable for both the MDD (chi(2) = 7.34, df 1, P = 0.006) and BP (chi(2) = 5.45, df 1, P = 0.02) patients. These findings support a possible role for genetically based structural variation in 5-HT2C receptors in the pathogenesis of major affective disorder.  相似文献   
77.
78.
The systemic and local immune response was studied in patients with alcoholic liver cirrhosis and the significance of the combined infection with HCV. To investigation were submitted 23 patients (16 males and 7 females) aged between 29 and 61 years with alcoholic liver cirrhosis. Of them 14 were anti-HCV(+) and 9 anti-HCV(-). As controls were used 36 clinically healthy individuals, matched by sex and age to the patients. The flow cytometric analysis of the lymphocyte (Ly) populations from the peripheral venous blood and of cells from liver aspirate obtained by blind liver biopsy according to Menghini, was performed with FacsTAR (Becton Dickinson). In the anti-HCV(-) patients, as compared to the controls (patients/controls) the Ly subpopulations were increased: CD3+/mm3:2010 +/- 738/1440 +/- 388; CD4+/mm3:1350 +/- 441/991 +/- 442; IL-2R+/mm3:133 +/- 78.5/31 +/- 20. In the anti-HVC(+) patients we established increased IL-2R+/mm3: 170 +/- 126 as compared with the controls and anti-HCV(-) patients. The suppressor/cytotoxic (CD8+) Ly with their suppressor (CD8+CD11b+) and cytotoxic (CD8+CD11b-) subpopulations and natural killers (CD16+) had a tendency to diminution in the anti-HCV(+) patients. In both examined groups the B (CD19+) Ly were non-significantly increased. The flow cytometric analysis of the cells from the liver specimen in 9 patients of whom 3 anti-HCV(-) and 6 anti-HCV(+) revealed that CD3+ on the average were 32.8% +/- 20.4% (from 9.2% to 65.1%); CD4+ were 21.1% +/- 7.4% (from 12.0% to 34.5%); CD8+ 22.6% +/- 11.8% (from 4.7% to 39.8%) and their values were higher in the anti-HCV(+) patients; the correlation CD4+/CD8+ = 1/1.09 +/- 0.6; CD16+ were 12.9% +/- 10.1% (from 1.9% to 34.8%); CD19+ varied from 3.2% to 27.8%; monocytes (CD14+) were 7.69% +/- 5.65 (from 2.0% to 15.8%) from the cells of the aspirate and their percentage contents was higher in the anti-HCV(+) patients. The results of out study revealed that in patients with alcoholic liver cirrhosis changes in the cell immune response were also observed and that they were more marked in infection with HCV.  相似文献   
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80.
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