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61.
62.
PURPOSE: To describe a case of ocular tilt reaction caused by vasculitic lesions in the midbrain in a child with polyarteritis nodosa. DESIGN: Observational case report. METHODS: A 5-year-old girl with a chronic illness developed diplopia associated with a left head tilt, right hypertropia, torsional nystagmus, slowed vertical saccades and poor convergence. Fundoscopic examination demonstrated conjugate leftward torsion of the eyes consistent with a sustained ocular tilt reaction.Renal angiography confirmed polyarteritis nodosa and cerebral magnetic resonance imaging demonstrated mesencephalic pathology. CONCLUSIONS: Polyarteritis nodosa is a difficult condition to diagnose in a child and can cause brainstem lesions. This rare case of ocular tilt reaction of midbrain origin highlights that a sustained head tilt in a child can be due to brainstem pathology, rather than a fourth nerve palsy.  相似文献   
63.
4-Methylbenzylidene-camphor (4-MBC) is an organic sunscreen that protects against UV radiation and may therefore help in the prevention of skin cancer. Recent results on the estrogenicity of 4-MBC have raised concerns about a potential of 4-MBC to act as an endocrine disruptor. Here, we investigated the direct interaction of 4-MBC with estrogen receptor (ER) alpha and ERbeta in a series of studies including receptor binding, ER transactivation and functional tests in human and rat cells. 4-MBC induced alkaline phosphatase activity, a surrogate marker for estrogenic activity, in human endometrial Ishikawa cells. Interestingly, 4-MBC induced weakly ERalpha and with a higher potency ERbeta mediated transactivation in Ishikawa cells at doses more than 1 microM, but showed no distinct binding affinity to ERalpha or ERbeta. In addition, 4-MBC was an effective antagonist for ERalpha and ERbeta. In an attempt to put 4-MBC's estrogenic activity into perspective we compared binding affinity and potency to activate ER with phyto- and xenoestrogens. 4-MBC showed lower estrogenic potency than genistein, coumestrol, resveratrol, bisphenol A and also camphor. Analysis of a potential metabolic activation of 4-MBC that could account for 4-MBC's more distinct estrogenic effects observed in vivo revealed that no estrogenic metabolites of 4-MBC are formed in primary rat or human hepatocytes. In conclusion, we were able to show that 4-MBC is able to induce ERalpha and ERbeta activity. However, for a hazard assessment of 4-MBC's estrogenic effects, the very high doses of 4-MBC required to elicit the reported effects, its anti-estrogenic properties as well as its low estrogenic potency compared to phytoestrogens and camphor has to be taken into account.  相似文献   
64.
Milk contains biologically relevant concentrations of erythropoietin (Epo), the primary hormone responsible for erythrocyte production. In animals, milk-borne Epo stimulates erythropoiesis. Epo receptors have been found in nonerythropoietic tissues including gastrointestinal tract. We hypothesized that milk-borne Epo is distributed to local gastrointestinal tissues, absorbed intact, and then distributed peripherally via the systemic circulation. Rat milk protected recombinant human Epo (rhEpo) from degradation in the suckling rat gastrointestinal tract. Simulated digestion of (125)I-rhEpo in suckling rat gastrointestinal juices was performed. When measured by acid precipitation and immunoassay, rat milk protected rhEpo from gastrointestinal juices better than saline (p < 0.0001). The fate of enterally administered milk-borne (125)I-rhEpo was examined in 10-d-old rats. RhEpo fed in rat milk was better protected from in vivo proteolytic degradation than rhEpo in saline (p < 0.05). After enteral (125)I-rhEpo dosing, radiolabeled protein from gastric tissue comigrated on SDS-PAGE with intact rhEpo at 36.5 kD. To determine the local and systemic distribution of physiologic intakes of rhEpo, suckling rats were fed (125)I-rhEpo in rat milk, and tissues were harvested 1, 2, and 4 h later. Intact (125)I-rhEpo was found in gastric and small intestinal walls and lumens. Five percent of total administered dose was found intact in the plasma, whereas another 8 to 10% of total administered dose was localized to bone marrow, percentages comparable to those seen after parenteral administration. Radiolabel was also localized to liver and peripheral solid tissues. These patterns of localization and degradation of rhEpo after acute administration support both systemic absorption and gastrointestinal cellular processing.  相似文献   
65.
PURPOSE: Authors report an unexpected association between PEX and ARMD. It was an additional result of a study, that analysed possible systemic symptoms of pseudoexfoliation material in visceral organs. They reviewed literature data for both, concerning epidemiology and physiopathogeny. MATERIAL AND METHODS: We conducted an age-and sex matched study of 142 patients in Brittany, 71 PEX and 71 controls, 31 men and 40 women in the 2 groups. The statistical study was performed with Epi Info 6.0 software using the X2 of Mantel-Haenszel Test. RESULTS: Statistical positive relation was found between PEX and ARMD (p=0.02), both increasing with age. DISCUSSION AND CONCLUSION: Part of epidemiology seems to be similar in PEX and ARMD, especially environment role (particularly solar radiations), individual factors, and genetic predisposition. For the first time, in may 1999, a genetic localization of PEX was discovered on the chromosome II, and nearly of one loci of ARMD multiple localizations.  相似文献   
66.
Cardiac involvement by intravascular protruding renal cell carcinoma is a well-recognised phenomenon. It most commonly occurs through inferior vena cava extension. Here, we report a case of a lower lobar lung metastasis from renal cell carcinoma involving the left atrium via the inferior pulmonary vein in a patient presenting with von Hippel-Lindau disease. Complete surgical resection was achieved under cardiopulmonary bypass.  相似文献   
67.
Risk factors related to increased mortality were determined on the basis of 329 aortocoronary bypass operations. They were: (1) emergency surgery, (2) poor left ventricular function, (3) reoperation, and (4) pulmonary hypertension. Angina pectoris, recent myocardial infarction, age over 65 years, obesity, significant systemic disturbances, smoking, arterial hypertension, and sex were without effect.  相似文献   
68.
Dysplasia epiphysealis hemimelica can be diagnesed on plain radiographs of the affected areas. However, double contrast arthrography in three new cases provided additional information. The cartilaginous portions of the lesion at the articular surface of the bone were precisely demonstrated, aiding the orthopedic surgeon in deciding which patients should have surgery and planning the extent of operation necessary.  相似文献   
69.
The influence of 3 different, preoperatively given glucocorticoids (30 mg/kg bw methylprednisolone, 3 mg/kg bw dexamethasone, 30 mg/kg hydrocortisone) on extravascular lung water (EVLW) was investigated in a randomised study consisting of 60 patients undergoing elective aortocoronary bypass surgery and compared to a control group having received 0.9% NaCl as placebo. EVLW-measurements were performed by using the double indicator dilution technique with indocyanine green and a microprocessed lung water computer. Besides EVLW-measurements haemodynamics and various laboratory data were studied before as well as after (15 min, 45 min, 5 h) extracorporeal circulation (ECC). ECC was followed by an increase in EVLW, which was less pronounced in the dexamethasone-group without being statistically significant (p = 0.1), however. Pulmonary gas exchange, too, did not differ statistically, in spite of a less pronounced (p = 0.1) deterioration of paO2 in the dexamethasone-group. Haemodynamics and laboratory data in the corticoid-group did not show any significant difference compared to the non-treated control group. It was concluded, that pretreatment with corticoids in pharmacological doses in cardiac surgery had no beneficial effects on extravascular lung water and pulmonary function.  相似文献   
70.
The influence of different vasopressors (Akrinor, etilefrine, ephedrine, norfenefrine, ameziniummetilsulfate) on arterial perfusion pressure and oxygenator volume during extracorporeal circulation was compared to a control group. All substances led to an increase in perfusion pressure, thus demonstrating a direct influence on arterial vessels. The rise in arterial pressure after injection of ameziniummetilsulfate persisted during the investigation period, whereas norfenefrine led to a short-lasting, but massive increase. No rise in venous tone was noticed during the investigation period.  相似文献   
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