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Hybridomas secreting monoclonal antibodies to HBsAg and HBcAg were prepared from immunized mice. An antibody capture radioimmunoassay was used to detect and select appropriate hybrids for propagation and cloning. The advantages of this assay were discussed. The resulting monoclonal antibodies were compared with conventional polyclonal antisera for the detection of virus antigens in liver tissue and found to give excellent results.  相似文献   
104.
An attempt was made to produce a model of autoimmune hepatitis in AKR mice by immunization with allogeneic liver extract or a purified (human) liver-specific lipoprotein (LSP). Although a mononuclear infiltrate was found in the liver in recipients of purified liver antigen and to a lesser degree in recipients of allogeneic extract, this was associated with the development of an acute thymus-derived leukaemia. This mouse strain is normally susceptible to leukaemia after a latent period of approximately 6 to 9 months but the immunization schedule markedly reduced the age of onset of this disease.  相似文献   
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PURPOSE: To analyze long-term prognosis and morbidity after limb-sparing treatment of patients with extremity soft-tissue sarcoma, with intraoperative electron boost radiotherapy (IOERT) followed by a moderate dose of external beam radiotherapy (EBRT). METHODS AND MATERIALS: A total of 153 patients who were treated in a single center from 1991 to 2004 were evaluated. Median IOERT dose was 15 Gy, mean EBRT dose 43 Gy (range, 40-50.4 Gy) in conventional fractionation (1.8-2 Gy). Median duration of follow-up was 33 months. Acute toxicity was assessed with Common Toxicity Criteria; late toxic effects were scored according to European Organization for Research and Treatment of Cancer/Radiation Therapy Oncology Group criteria. RESULTS: Five-year overall survival and 5-year local control rates were 77% and 78%, respectively. Whereas tumor size, patient age, and EBRT dose did not significantly affect outcome, resection status and grading were significant for survival; resection status and IOERT dose were significant for local control. Extremity salvage until death or time of follow-up was achieved in 90% of our patients, 86% of whom showed excellent limb function without impairment in activities of daily life. Acute toxicity Grade 2-4 was observed in 23% and late toxicity Grade 2-4 in 17% of patients. CONCLUSIONS: Treatment with IOERT combined with moderate doses of external beam irradiation yields high local control and extremity preservation rates in resected extremity soft-tissue sarcoma.  相似文献   
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PURPOSE: To describe the clinical features of post-streptococcal uveitis (PSU) and examine management strategies in the treatment of this under-recognized condition. METHODS: Patients were identified from the world literature using the Pubmed search engine. We examined two new cases of post-streptococcal intermediate uveitis. The epidemiology, immune mechanisms, clinical features, investigations, treatments and visual outcomes were examined and recorded. RESULTS: We reviewed 11 patients including our own two cases. There was a statistically significant seasonal difference in antistreptolysin-O titres (ASOT), and age-related ASOT was identified. Of the 11 patients, eight (72.7%) had anterior uveitis, two (18.2%) had intermediate uveitis and one (9.1%) had panuveitis. Their ages ranged from 5 to 56 years (mean 17 years). The majority of cases had significantly elevated ASOT; most patients were treated with topical steroids and oral antibiotics and four cases underwent adenotonsillectomy. The visual prognosis was good in most cases. CONCLUSIONS: Uveitis may be the sole presenting clinical feature, or it may occur in combination with other features of post-streptococcal infection. Ophthalmologists should be aware of the clinical features of PSU and maintain a high level of suspicion, particularly in childhood uveitis.  相似文献   
108.
The response of peripheral blood leucocytes to PPD was studied in vitro by means of the leucocyte migration test, using Mantoux-positive and -negative subjects. The migration of leucocytes from 83% of the positive subjects was significantly inhibited when a concentration of 100 μg PPD/ml was used in the chambers. Leucocytes from the majority of these subjects were also inhibited at a lower concentration of 50 μg PPD/ml and one strongly positive subject showed inhibition at all concentrations tested, down to 1 μg PPD/ml. Stimulation of migration was not observed with leucocytes from any of the positive subjects even when the lowest concentration of PPD was used. Inhibition of migration with PPD was prevented by the addition of puromycin, suggesting that the response is dependent on protein synthesis and may be mediated by a soluble factor produced by sensitized lymphocytes.  相似文献   
109.
The rabbit pulmonary artery was used to examine whether presynaptic serotonin (5-HT) receptors modulate noradrenaline (NA) release also in this blood vessel and to confirm their presence with molecular biology techniques. Arteries preincubated with [3H]NA were superfused in the presence of the alpha2-adrenoceptor blocker rauwolscine and the effects of 5-HT receptor ligands on the electrically evoked 3H overflow were determined. The 5-HT4 receptor agonist cisapride inhibited 3H overflow in a manner sensitive to blockade by atropine. The 5-HT1B/1D receptor agonist 5-carboxamidotryptamine inhibited 3H overflow only in the presence of atropine. The 5-HT4 and 5-HT1B/1D receptor agonists 5-HT and 5-methoxytryptamine reduced 3H overflow in the absence and presence of atropine, and this effect was blocked by methiothepin, a non-selective 5-HT receptor antagonist, in the presence of atropine. PCR with cDNAs derived from reverse transcribed blood vessel mRNA suggested the expression of the 5-HT1B, 5-HT1D and 5-HT4 receptors, the latter being highly homologous to the human one. In conclusion, the cholinergic nerves are endowed with excitatory 5-HT4 receptors mediating release of acetylcholine which, in turn, activates muscarine receptors on the sympathetic nerves leading to inhibition of NA release. Blockade of the presynaptic muscarinic receptors involved is necessary to disclose an inhibition of NA release via 5-HT1B/1D receptors. Taking results reported in the literature into account, the 5-HT1D and 5-HT4 receptors identified by molecular biology techniques probably are located predominantly on the noradrenergic and cholinergic neurons, respectively.  相似文献   
110.
OBJECTIVES: Most data on self-poisoning in rural Asia have come from secondary hospitals. We aimed to: assess how transfers from primary to secondary hospitals affected estimates of case-fatality ratio (CFR); determine whether there was referral bias according to gender or poison; and estimate the annual incidence of all self-poisoning, and of fatal self-poisoning, in a rural developing-world setting. METHODS: Self-poisoning patients admitted to Anuradhapura General Hospital, Sri Lanka, were reviewed on admission from 1 July to 31 December 2002. We audited medical notes of self-poisoning patients admitted to 17 of the 34 surrounding peripheral hospitals for the same period. FINDINGS: A total of 742 patients were admitted with self-poisoning to the secondary hospital; 81 died (CFR 10.9%). 483 patients were admitted to 17 surrounding peripheral hospitals. Six patients (1.2%) died in peripheral hospitals, 249 were discharged home, and 228 were transferred to the secondary hospital. There was no effect of gender or age on likelihood of transfer; however, patients who had ingested oleander or paraquat were more likely to be transferred than were patients who had taken organophosphorus pesticides or other poisons. Estimated annual incidences of self-poisoning and fatal self-poisoning were 363 and 27 per 100,000 population, respectively, with an overall CFR of 7.4% (95% confidence interval 6.0-9.0). CONCLUSION: Fifty per cent of patients admitted to peripheral hospitals were discharged home, showing that CFRs based on secondary hospital data are inflated. However, while incidence of self-poisoning is similar to that in England, fatal self-poisoning is three times more common in Sri Lanka than fatal self-harm by all methods in England. Population based data are essential for making international comparisons of case fatality and incidence, and for assessing public health interventions.  相似文献   
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