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101.
102.
Localization of language function in children: results of electrical stimulation mapping 总被引:7,自引:0,他引:7
OBJECT: The authors examined the localization of language sites and the frequency of naming errors at these sites in a population of children undergoing electrical stimulation mapping during surgeries in which epileptic foci and dominant hemisphere neoplasms were resected. The frequency with which essential language sites were found (that is, "the frequency of language sites") in children was compared with that of a population of adults who had undergone this procedure, to assess the relationship of age to the distribution of essential areas for language. METHODS: The results of electrical stimulation mapping to determine sites of naming and speech arrest in 26 children ranging in ages from 4 to 16 years are presented in this report. Mapping was performed in the intraoperative setting in eight patients and in the extraoperative setting, by stimulation across a subdural grid, in 18 patients. The frequency and distribution of essential language areas were analyzed in populations of different ages and according to the method used to obtain the map. Considerable variability was found in the localization of language sites. When the language site distribution in pediatric patients was compared with the language site distribution found previously in a population of patients older than 16 years of age, a relative paucity of language sites was found in all perisylvian cortices in the younger age group. This relationship was also found within the group of patients 16 years of age and younger, when segregated into two groups: those patients 8 years of age or younger, and those patients between 9 and 16 years of age. These findings are relevant to theories of the intrahemispheric organization of the cortex devoted to language function. CONCLUSIONS: The differences found between groups of younger and older patients in the frequencies of sites where stimulation produces naming errors was identified suggests the possibility that, with advancing age, maturational processes contribute new foci of cortex essential for language. 相似文献
103.
Traditionally, surgical sigmoid diverticular emergencies used to be treated in stages, but more recently there has been a trend towards definitive surgery with immediate resection plus anastomosis under certain conditions. The aim of this study was to define the morbidity and mortality of resection plus anastomosis with on-table antegrade irrigation and of the Hartmann procedure for complicated sigmoid diverticulitis in relation to the type of peritonitis and to the American Society of Anesthesiologists (ASA) grade of the patients. From April 1999 to April 2002, 38 emergency operations for complicated sigmoid diverticulitis were performed at the San Sebastiano Hospital in Caserta. Six patients underwent operations for obstructions and 32 for perforation (19 Hinchley stage III and 13 Hinchley stage IV). Surgical therapy for obstruction consisted in 4 resections plus anastomosis, 1 subtotal colectomy and 1 Hartmann procedure. Surgical therapy for perforation consisted in 14 resections plus anastomosis and 18 Hartmann procedures. There was 1 case (5%) of anastomotic dehiscence out of 19 primary anastomoses versus 2/19 surgical complications (10%) after the Hartmann procedure. The mortality amounted to 1 death out of 38 (2.6%) in a patient treated with the Hartmann procedure. Left-sided colonic obstruction should be treated by resection plus anastomosis or by subtotal colectomy for ASA II-III patients and by Hartmann's procedure for ASA IV-V patients. ASA II-III patients with localised or generalised non-faecal peritonitis should be treated by resection plus anastomosis, while a Hartmann procedure should be the reasonable option for generalised faecal peritonitis and for ASA IV-V patients with localised or generalised non-faecal peritonitis. 相似文献
104.
Downregulation of bcl-2 expression in lymphoma cells by bcl-2 ARE-targeted modified,synthetic ribozyme 总被引:2,自引:0,他引:2
Luzi E Papucci L Schiavone N Donnini M Lapucci A Tempestini A Witort E Nicolin A Capaccioli S 《Cancer gene therapy》2003,10(3):201-208
Synthetic ribozymes are catalytic RNA molecules designed to inhibit gene expression by cleaving specific mRNA sequences. We investigated the potential of synthetic ribozymes to inhibit bcl-2 expression in apoptosis defective bcl-2 overexpressing tumors. A chemically stabilized hammerhead ribozyme has been targeted to the A+U-rich regulative element of bcl-2 mRNA that is involved in bcl-2 gene switch-off during apoptosis. The design of the ribozyme was based on the results of probing accessibility of the RNA target in cellular extracts with antisense DNA. The ribozyme was lipotransfected to a bcl-2 overexpressing human lymphoma cell line (Raji). The cellular uptake of this ribozyme resulted in a marked reduction of both bcl-2 mRNA and BCL-2 protein levels and dramatically increased cellular death by apoptosis. Our results suggest a potential therapeutic application of such ribozyme for the treatment of bcl-2 overexpressing tumors. 相似文献
105.
Gallus S Bosetti C Negri E Talamini R Montella M Conti E Franceschi S La Vecchia C 《International journal of cancer. Journal international du cancer》2003,107(2):283-284
We analyzed the potential role of pizza on cancer risk, using data from an integrated network of case-control studies conducted in Italy between 1991 and 2000. Cancer sites were: oral cavity and pharynx (598 cases), esophagus (304 cases), larynx (460 cases), colon (1,225 cases) and rectum (728 cases). Controls were 4,999 patients admitted for acute, non-neoplastic conditions to the same hospital network as cases. Odds ratios for regular pizza consumers were 0.66 (95% confidence interval, CI = 0.47-0.93) for oral and pharyngeal cancer, 0.41 (95% CI = 0.25-0.69) for oesophageal, 0.82 (95% CI = 0.56-1.19) for laryngeal, 0.74 (95% CI = 0.61-0.89) for colon and 0.93 (95% CI = 0.75-1.17) for rectal cancer. Pizza appears therefore to be a favorable indicator of risk for digestive tract neoplasms in this population. 相似文献
106.
Mioni C Giuliani D Cainazzo MM Leone S Iannone A Bazzani C Grieco P Novellino E Tomasi A Bertolini A Guarini S 《European journal of pharmacology》2003,477(3):227-234
In rats subjected to myocardial ischemia/reperfusion, melanocortin peptides, including gamma(1)-melanocyte-stimulating hormone (gamma(1)-MSH), are able to exert a protective effect by stimulating brain melanocortin MC(3) receptors. A non-melanocortin receptor belonging to a group of receptors for Phe-Met-Arg-Phe-NH(2) (FMRFamide)-like peptides may be involved in some of the cardiovascular effects of the gamma-MSHs. FMRFamide-like peptides and gamma(1)-/gamma(2)-MSH share, among other things, the C-terminal Arg-Phe sequence, which seems to be essential for cardiovascular effects in normal animals. So we aimed to further investigate which receptor and which structure are involved in the protective effects of melanocortins in anesthetized rats subjected to myocardial ischemia by ligature of the left anterior descending coronary artery (5 min), followed by reperfusion. In saline-treated rats, reperfusion induced, within a few seconds, a high incidence of ventricular tachycardia and ventricular fibrillation, and a high percentage of death within the 5 min of observation period. Reperfusion was associated with a massive increase in free radical blood levels and with an abrupt and marked fall in systemic arterial pressure. The i.v. treatment (162 nmol/kg) during the ischemic period with the adrenocorticotropin fragment 1-24 [ACTH-(1-24): the reference protective melanocortin which binds all melanocortin receptors], as well as with both the melanocortin MC(3) receptor agonists gamma(2)-MSH and [D-Trp(8)]gamma(2)-MSH, reduced the incidence of ventricular tachycardia, ventricular fibrillation and death, the increase in free radical blood levels and the fall in arterial pressure. On the contrary, gamma(2)-MSH-(6-12) (a fragment unable to bind melanocortin receptors) was ineffective. Such protective effect was prevented by the melanocortin MC(3)/MC(4) receptor antagonist SHU 9119. In normal (i.e., not subjected to myocardial ischemia/reperfusion) rats, the same i.v. dose (162 nmol/kg) of gamma(2)-MSH, [D-Trp(8)]gamma(2)-MSH and gamma(2)-MSH-(6-12) provoked a prompt and transient increase in arterial pressure; on the other hand, ACTH-(1-24), which lacks the C-terminal Arg-Phe sequence, decreased arterial pressure, but only at higher doses. Heart rate of normal rats was not affected by any of the assayed peptides. The present data confirm and extend our previous findings that melanocortins prevent myocardial reperfusion injury by activating melanocortin MC(3) receptors. Moreover, they further support the notion that, in normal rats, cardiovascular effects of gamma-MSHs are mediated by receptors for FMRFamide-like peptides, for whose activation, but not for that of melanocortin MC(3) receptors, the C-terminal Arg-Phe structure being relevant. 相似文献
107.
108.
Trotti R Rondanelli M Cuzzoni G Magnani B Gabanti E Ferrari E 《Functional neurology》2003,18(2):77-81
Age-related structural and neurochemical changes occurring in the central nervous system have been related to changes in some rhythmometric parameters. In spite of their clinical importance, only a few studies have investigated the modifications over time of serum electrolytes in senescence. The aim of our study was to evaluate the circadian pattern of serum potassium, chloride, sodium, calcium and phosphorus in 30 clinically healthy elderly subjects, with no cognitive impairment, and to compare the findings with those given by 24 healthy young controls. The subjects were synchronized as regards their daily activities, sleeping/waking habits, time/quality of meals and dietary electrolyte intake. After an overnight fast, samples were taken beginning at 08.00 and every 4 h thereafter until 20.00, and every 2 h from 20.00 to 04.00. Both the young and the elderly subjects exhibited statistically significant circadian rhythms for all serum electrolytes considered. Our findings suggest that circadian organization of serum electrolytes is maintained in physiological aging, even though it should be noted that sodium and phosphorus acrophases differed significantly in the two experimental groups. 相似文献
109.
Laurenti P Quaranta G Branca G Tumbarello M Capoluongo E Orsini M Romano Spica V 《Igiene e sanità pubblica》2003,59(4):203-214
The authors report the early results of a case-control study carried out about the risk of legionellosis. During the first year, they have tested urine samples from patients with unknown pneumonia, using a legionella-sensitive test for the detection of its antigen. Out of 171 samples, 9 have turned out to be positive (5.3%). Lifestyles, predisposing factors, possible sources of infection and stressful events were investigated. 相似文献
110.
Cicinelli E 《Best practice & research. Clinical obstetrics & gynaecology》2008,22(2):391-405
The vagina provides a local and a systemic route for delivering hormones for systemic effects and uterine targeting. Due to the 'uterine first-pass effect', hormones concentrate in the uterus and nearby tissues with low systemic exposure. Vaginal oestrogens, progesterone/progestins and danazol are currently used to obtain local (vagina and urethra), regional (uterus, pelvic structures) and systemic effects or contraception. Very low dosages of transvaginal oestrogens in the forms of creams, tablets and rings are effective for vaginal atrophy and urinary incontinence. To avoid endometrial stimulation, no deep vaginal application of low dosages for less than 6 months is recommended. For postmenopausal hormonal therapy by the vaginal route, progesterone is delivered directly to the uterus; the target organ for which it is designed. Worldwide, vaginal progesterone is employed for luteal phase support. Contraceptive vaginal rings offer the advantages of non-oral administration and sustained release. Vaginal administration of steroids is a promising option for the treatment of endometriosis. 相似文献