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991.
Burkholderia cepacia complex isolates obtained by microbiological culture of respiratory samples from Brazilian CF patients were studied by recA based PCR, screened by specific PCR for virulence markers and genotyped by RAPD. Forty-one isolates of B. cepacia complex were identified by culture and confirmation of identity and genomovar determination obtained in 32 isolates, with predominance of B. cenocepacia (53.1%). Virulence markers were not consistently found among isolates. Genotyping did not identify identical patterns among different patients. B. cenocepacia was the most prevalent B. cepacia complex member among our patients, and cross-infection does not seem to occur among them.  相似文献   
992.
BackgroundBurnout syndrome occurs frequently amongst oncology healthcare workers. It has a detrimental effect on the patient–physician relationship. Little is known about the prevalence and causes of burnout amongst junior doctors in oncology.MethodsAn anonymous questionnaire was sent out to every medical or radiation oncology or haematology resident in France (n = 340). It included: demographical data, burnout level (Maslach Burnout Inventory), sources of stress, sense of equity at work, sources of support, and general health questions. Validated scales were used when available. Two reminder e-mails were sent to increase the response rate.ResultsQuestionnaires were despatched during Spring 2009. The response rate was 60% (204/340). Emotional exhaustion (EE) and Depersonalisation (DP), the major components of burnout, were reported, respectively, by 26% (n = 53) and 35% (n = 72) of the residents. Burnout prevalence was 44% (n = 89), defined as a severely abnormal level of either EE or DP. Eighteen percent of the residents (n = 36) had severely abnormal levels of both EE and DP. The burnout level was not significantly different between the three specialties, but was higher amongst residents who do not feel adequately rewarded for their work (p < 0.001). Burnout was associated with a lower perception of one’s general health status (p < 0.001) and the desire to quit Medicine or to change specialty (p < 0.001).ConclusionThe burnout level is high amongst oncology residents. It probably discourages vocations for oncology. Interventions are needed and could include support groups, more intense coaching by senior physicians, training programmes on ‘breaking bad news’ and teaching of stress management skills.  相似文献   
993.
Toll-like receptors (TLRs) are cellular receptors that mediate recognition of microbial challenges and the subsequent inflammatory response. Genetic variations within these inflammation-associated genes may alter host-pathogen defence mechanisms affecting susceptibility towards infectious diseases. Taking into account the significance of these genes, we developed a simple and rapid method based in the bi-directional PCR amplification of specific alleles (Bi-PASA) for genotyping known sequence variants in TLR4 (Asp299Gly and Thr399Ile) and TLR9 (T-1237C) genes. This method allows genotype determination in a single reaction and is amenable to large-scale analysis. We used Bi-PASA to characterize the distribution of these polymorphisms in the Portuguese population. A total of 388 randomly selected blood donors of Portuguese origin (203 females and 185 males) were genotyped and allele frequencies were determined. Among the tested individuals, 11.1% and 10.8% were heterozygous for Asp299Gly and Thr399Ile, respectively. In what concerns the T-1237C variation in TLR9, the variant allele was present in 19.4% of the individuals tested. Besides confirming the usefulness of the Bi-PASA in polymorphism analysis, the data presented provide valuable information on TLR polymorphisms in the Portuguese population that can be used to stratify risk patients with increased susceptibility to infection.  相似文献   
994.
Here, for the first time, we report the nucleotide sequence of Caraparu virus (CARV) L segment and the analysis of the RNA polymerase region 3 encoded by this segment. The 1,404 bp nucleotide sequence shares the highest identity with Bunyamwera, La Crosse, Oropouche, and Akabane virus sequences. The amino acid sequence was deduced and aligned with sequences from members of the Bunyaviridae family and used for phylogenetic analysis. The CARV clustered in the Orthobunyavirus genus. The premotif A and motifs A–E are present in the region 3 of the Bunyaviridae family, were also conserved in CARV L protein, as well as other conserved regions among Orthobunyavirus genus. The nucleotide sequence data reported in this article have been submitted to the GenBank nucleotide sequence database: EF122411  相似文献   
995.
Physical or emotional stress can affect the female reproductive physiology and angiotensin II (Ang II) is a hormone that participates in the stress response and also in the control of reproductive hormones. The present study aimed at evaluating the effects of acute stress in the morning and afternoon of proestrus on sexual behavior and ovulation and the participation of Ang II in the stress-induced effects. Female rats with regular estrous cycles were used. Several different stress protocols were tested in the morning and in the afternoon of proestrus: restraint stress 10 min; restraint stress 1 h and ether stress, respectively. The participation of Ang II was evaluated by injecting Ang II receptor antagonists (losartan and PD123319) 15 min before stress. The lordosis quotient was recorded and the number of oocytes was counted. Plasma levels of luteinizing hormone, progesterone, prolactin and corticosterone were measured. All types of stress in the morning of proestrus induced a reduction in the number of oocytes. Restraint stress (1 h) in the afternoon of proestrus induced a significant reduction in the lordosis quotient. Peripheral and central losartan, but not PD123319, injections partly reverted the effects of stress on ovulation in the morning of proestrus. Acute stress in the morning of proestrus also reduced luteinizing hormone, progesterone and prolactin surges later on the same day. In conclusion, acute stress on the day of proestrus can affect female reproductive physiology. Moreover, the angiotensinergic system, through AT(1) receptors, participates in the effects of acute stress in the morning of proestrus.  相似文献   
996.
The human polyomaviruses--BKV and JCV--are members of Polyomaviridae family and after primary infections they persist as latent infection especially in the kidneys. BKV reactivation is mainly related to urinary tract diseases and JCV reactivation can induce the disease progressive multifocal leukoencephalopathy. The aim of our study was to characterize the excretion of polyomaviruses in urine samples of healthy individuals from a Portuguese population. We analyzed 498 DNA samples using PCR-RFLP, the sequence amplified consisted in 176 or 173 bp within the antigen T region. Our results indicate that 23.9% of the samples were positive for JCV, 1.8% positive for BKV and 74.3% of the individuals were negative for both viruses. We observed an increased prevalence of JCV shedding in male individuals in comparison to female (P = 0.026). Furthermore, the shedding of both polyomaviruses was influenced by the age of individuals with a significant increase in individuals with more than 56 years old (P = 0.005). Our results show that the shedding of polyomavirus in urine of healthy individuals is highly variable between genders, is influenced by age and differs from region to region. Further studies are needed to evaluate the prevalence of polyomaviruses in healthy individuals, in order to understand the biological behaviour of these viruses.  相似文献   
997.
The purpose of this study was to test in vivo two different nerve guides, one of PLGA made of a novel proportion (90:10) of the two polymers, Poly(L-lactide):Poly(glycolide), with (DL-lactide-epsilon-caprolactone) copolyester (Neurolac) tube, in promoting nerve regeneration across a 10 mm-gap of the rat sciatic nerve. Finally, end-to-end coaptation was performed. Motor and sensory functional recovery was assessed throughout the healing period of 20 weeks and the repaired nerves were processed for morphological analysis. Both motor and sensory functions improved significantly in all experimental nerve repair groups, although the rate and extent of recovery was significantly higher in the end-to-end group. No significant differences were detected in the comparison between the two types of tubes. Compatible with results of functional tests, morphological analysis showed that axon regeneration occurred in both PLGA and Neurolac experimental groups but disclosed a different pattern of degradation of the two types of tubes with larger biodegradation of PLGA material by the end of 20 weeks. These results suggest that both types of biomaterial are a good substrate for preparing tubular nerve guides and the different pattern of degradation does not seem to influence the degree of nerve regeneration.  相似文献   
998.
999.
Fish is an important item in the diet of Amazonians, and per se is their best single source of essential nutrients. Rapid urbanization and migration are bringing changes in dietary habits of Amazonians. Exposure to fish-Hg during pregnancy and lactation were studied in 100 women and newborns from Porto Velho. Tissue-Hg concentrations and neurodevelopment (Gesell Developmental Schedules) were assessed at birth and at 6 months in exclusively breastfed infants. Maternal mean frequency of fish consumption was low (<2 meals/week; range 0->7 meals/week) compared to Amazonian standards. Women consuming <2 fish meals/week showed less median hair-Hg (3.5 microgg-1) than women that consumed 2 fish meals/week (5.7 microgg). Median total Hg in maternal hair (5.4 microgg-1) was higher than in newborns (1.6 microgg-1). Significant correlation was observed between maternal hair-Hg and infant hair-Hg at birth (r=0.353; p<0.01) and at six months (r=0.510; p<0.01). Placenta-Hg was also significantly correlated to maternal hair-Hg (r=0.321; p<0.01), newborn hair-Hg (r=0.219; p<0.05), maternal blood-Hg (r=0.250; p<0.01) and to umbilical cord-Hg (r=0.857; p<0.01). Most infants (74%) had normal Gesell Schedules but among the 26% showing neuro-motor development delays only six (7%) had multiple (motor, language, and adaptative) delays. The infants with multiple delays were born from mothers with range of hair-Hg comparable to mothers of normally developed infants. Coincidentally, mothers of infants with multiple delays also showed the lowest range of income and level of education. Fish consumption, income, and level of education varied greatly among these breastfeeding urban mothers. It seems that development delays of exclusively breastfed infants are a component of the health inequalities that accompanies socioeconomic disadvantages.  相似文献   
1000.
The study presents the professional profiles and work conditions of nutritionists who graduated from the Ouro Preto Federal University, Minas Gerais State, Brazil, in their various spheres of action. A quanti-qualitative approach was adopted through questionnaires completed by all professionals graduating from this University between 1994 and 2001 (N=356), in addition to semi-structured interviews with fourteen professionals selected from the universe of the respondents (n=90). An analysis of these questionnaires showed that 67% of them work with Clinical Nutrition, 44% with Collective Nutrition, 14% with Education Programs and 11% with Social Nutrition. Most (57%) of the respondents expressed the desire to remain in the field where they were working. Among those wishing to move into a different area, 44.5% work with Collective Nutrition. Despite clearly precarious employment links, Clinical Nutrition is the field with the largest number of professionals satisfied with their work conditions. The findings of this study explore the work conditions of a group of nutritionists for whom job stability is not always the main factor for professional satisfaction.  相似文献   
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