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81.
Summary We report on 16 cases of suspected spondylitis in which we used magnetic resonance (MR) imaging to confirm or exclude the diagnosis. MR has several advantages, one of which is to permit diagnosis of this disease in the early stages without major risks. In addition, MR permits recognition of complications such as paravertebral or intraspinal abscess formation with a high security and accuracy. Moreover, it is possible to show spondylitic alterations in three different planes. To differentiate this disease from metastatic or tumorous lesions the technique with T1- and T2-weighted images is helpful. As a result, MR imaging can shorten the time between onset and diagnosis of spondylitis.
Zusammenfassung Es wird über 16 Patienten mit hämatogener bakterieller Spondylitis oder Verdacht auf einen entzündlichen Wirbelsäulenprozeß berichtet, bei denen die Magnetresonanztomographie (MR) diagnostisch angewandt wurde. Diese Methode erlaubt aufgrund ihrer technischen Bedingungen unabhängig von Röntgenstrahlen eine Spondylitis frühzeitig zu erfassen und kann entsprechende Veränderungen in drei verschiedenen Ebenen abbilden. Außerdem kann das Ausmaß eventueller begleitender paravertebraler und/oder intraspinaler Abszesse mit hoher Genauigkeit und Sicherheit dargestellt werden. Dies ist besonders für die operative Therapie vorteilhaft. Weiterhin ist aufgrund der Zuhilfenahme sog. T1- und T2-gewichteter Bilder die Differential-diagnostik zu anderen Erkrankungen der Wirbelsäule möglich. Auch können ausgeprägtere Veränderungen der kalkhaltigen Gewebsanteile dargestellt werden. Im Vergleich zu anderen diagnostischen Methoden besitzt die MR mehrere Vorteile in einer Methoden Dies dürfte einen wesentlichen Beitrag zur Frühdiagnose dieser Krankheit leisten.相似文献
83.
HJ Maas M Danhof & OE Della Pasqua 《Cephalalgia : an international journal of headache》2009,29(7):772-780
In migraine, headache severity varies with age. As a consequence, the effectiveness of medication may also depend on a patient's age. The purpose of this study was to assess the combined effect of age and drug treatment on headache characteristics. Using data from clinical trials of sumatriptan in adolescents and adults, we show how the interaction between age and drug exposure can be parameterised as a covariate on a Markov model that describes the decline of headache severity over three clinically defined stages (no relief, relief and pain-free status). The model explains important clinical observations: (i) the rates at which the pain relief and pain-free status were attained were found to be inversely related to age; (ii) in placebo-treated patients, the mean transit time from 'no relief' to 'relief' is 3 h for young adolescents and increases to 6 h for patients aged ≥ 30 years; and (iii) sumatriptan reduces the transit time to 2 h, irrespective of age. These findings indicate that the therapeutic gain over placebo increases with age. Prospective studies of antimigraine drugs should take this relationship into account when extrapolating efficacy data from adults to adolescents. 相似文献
84.
85.
We have investigated the action of exogenous nitric oxide (NO) on the strength and contractile properties of human skeletal muscle working in vivo. Maximum isometric voluntary contraction force (MVC) of the quadriceps was measured and superimposed electrical stimulation was used to estimate the level of activation and 'true maximum force' (TMF). Force-frequency relationships were determined to assess changes in contractile properties of the muscle. Subjects in the experimental group (E, n=10) were measured before and during two separate periods of treatment with different doses of glyceryl trinitrate, a NO donor, delivering 100 (GTN100) or 200 (GTN200) microg h-1 as a trans-dermal patch. A control group (C, n=6) was measured during two similar periods whilst taking an oral placebo. There was a significant increase in strength with GTN200 (MVC: +5. 15%; TMF: +3.87%). There was no change in the strength of group C. There was a trend towards reduced forces at submaximal frequencies with GTN administration but the most notable change was a decline in twitch force (approximately 12%, P < 0.05) with GTN100 treatment and this remained depressed throughout the study. No changes were seen in the contractile properties of the control group C. The present results show that GTN treatment increased maximum voluntary strength but decreased twitch tension. The time course and dose-response characteristics indicate that these are two separate actions of NO on human muscle working in vivo. 相似文献
86.
M M van Zalen-Sprock J M van Vugt V H Karsdorp R Maas H P van Geijn 《Prenatal diagnosis》1991,11(8):655-660
Over a 6 1/2 year period, in 288 pregnancies a variety of fetal malformations were detected by ultrasound. Two hundred and ten fetuses (73 per cent) were karyotyped. Gestational age at detection ranged from 11 to 38 weeks. The incidence of an abnormal karyotype in the total series was 14 per cent and 14.7 per cent in the 210 pregnancies in which a karyotype was performed. Single structural anomalies were found in 149 cytogenetically investigated fetuses, of which 25 had a chromosomal abnormality (17 per cent). Multiple structural malformations were present in 61 fetuses, of which 16 had an abnormal karyotype (26 per cent). Trisomy 18 was the most frequent finding. The most constant ultrasound finding in cases of an abnormal karyotype was polyhydramnios and severe IUGR in combination with structural defects. There is a need for extensive detailed ultrasound examination in high-risk pregnancies. 相似文献
87.
A reduction in airway beta-adrenoceptor density has been reported in cystic fibrosis lung but the mechanism underlying this defect remains unclear. In this study, we have investigated whether the decrease in beta2-adrenoceptor associates with altered G protein-coupled receptor kinase (GRK) levels. We assessed GRK activity by rhodopsin phosphorylation, and beta2-adrenoceptor and GRK at the mRNA and protein levels by Northern and Western blotting in peripheral lung samples from normal donors and patients with cystic fibrosis. GRK activity was significantly increased in peripheral cystic fibrosis lung with parallel increases in GRK2/5 mRNAs and protein expression. Functionally, isoproterenol-stimulated adenylyl cyclase activity was also diminished by 65% in cystic fibrosis lung homogenates. These data suggest that the increase in GRK activity may be one of the mechanisms underlying alterations in the coupling between beta2-adrenoceptor and adenylyl cyclase via G-protein and may thus contribute to the downregulation of beta2-adrenoceptor in cystic fibrosis lung. 相似文献
88.
Kamel HK Iqbal MA Mogallapu R Maas D Hoffmann RG 《The journals of gerontology. Series A, Biological sciences and medical sciences》2003,58(11):1042-1045
OBJECTIVE: To test the hypothesis: Time to ambulation (walking) after hip fracture surgery impacts the frequency of postoperative complications and length of hospital stay. METHODS: A retrospective observational study of a cohort of all patients admitted to a university teaching hospital with a principal International Classification of Diseases-9 diagnosis of a hip fracture during 3 calendar years. RESULTS: A total of 131 participants were identified (68% were aged 65 years or older). Overall, the mean time to writing an order to ambulate a patient after a hip fracture surgery was 2 +/- 1.5 days. Time to ambulation after hip fracture surgery was significantly less in patients cared for on orthopedic surgery service compared to general surgery service (1.8 +/- 1 vs 2.5 +/- 2, p <.05) or general internal medicine service (2.5 +/- 1.5, p <.05). It did not relate, however, to patient's age, sex, or race, or to patient's functional status prior to admission, fracture site (femoral neck, intertrochanteric, or subtrochanteric), whether a femoral neck fracture is displaced or not, type of anesthesia (spinal/epidural vs general), type of surgery (open reduction and internal fixation vs hemiarthroplasty), degree of preoperative risk, number of medical conditions, or to obtaining physical therapy and/or medical consultation. Time to ambulation after surgery was an independent predictor for the development of pneumonia (1.5 OR [odds ratio]/day, p <.001), new onset delirium (1.7 OR/day, p <.001), and to prolonged length of hospital stay (B [slope coefficient] = 1.36, p <.0001) but not to the development of pressure ulcers, deep venous thrombosis, or urinary tract infection. CONCLUSIONS: Delayed ambulation after hip fracture surgery is related to the development of new onset delirium and pneumonia postoperatively as well as to increased length of hospital stay. Early ambulation after hip fracture surgery should be encouraged. 相似文献
89.
It is increasingly recognized that even very low lead exposure can result in measurable and permanent neurologic damage, especially to infants and young children. Although lead exposure from tap water continues to decline in the United States as a result of various regulatory and corrosion control measures, tap water continues to represent a significant (about 14 to 20 percent) source of total lead exposure. As of March 2002, nearly all valves used in residential plumbing systems continue to be made with 5 to 7 percent leaded brass. In this study, the authors measured the amount of lead discharged by these parts under laboratory conditions and found that the typical resident would be exposed to small amounts of lead, particularly from gate and ball valves. Typically, water passes through three to six such valves before reaching the tap. Thus, these leaded-brass valves represent a significant, widespread, and needless source of lead exposure to the U.S. public, especially given that numerous models of no-lead valves are now commercially available. 相似文献
90.
In an advisory report to the Dutch Government, the Health Council of the Netherlands has recently recommended offering triple test serum screening for Down's syndrome to all pregnant women. According to a critical review in this journal, the Council should have proposed excluding those less than 30 years of age. However, there is no age at which a logical limit can be set. Moreover, to suggest that the negative aspects of the screening will prevail for those under a specific age, denies the women involved the right to make a judgment based on their own values and preferences. Secondly, although limited resources may be a reason for limiting access to screening, doing so would be a politico-ethical decision, which raises the issue of justice. Finally, there are reasons for thinking that a new age limit would complicate the necessary counselling as opposed to making it easier. 相似文献