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991.
The level of psychiatric morbidity and perceived sources of stress among police officers were investigated using the General Health Questionnaire (GHQ) and a stress situation questionnaire, which were sent to 171 officers. Half of the responders were invited to attend group counselling sessions weekly for 12 weeks. Outcome measures studied were a second GHQ completed at the end of the treatment period and the amounts of sick leave taken in the 12-week period before, during and after the treatment period. The results were that 61 people returned the first GHQ of whom 59 were male and of whom 14 were classed as ‘cases’. Of the 31 assigned to the treatment group, 22 attended at least one session. Responses to the stress situation questionnaire and the content of counselling sessions tended to confirm the impression that internal aspects of the organization were viewed as prime sources of stress and dissatisfaction. There were no significant changes in GHQ score within or between groups, nor were there significant differences in the amount of sick leave taken. Nevertheless the sessions appeared to be valued and we conclude that this sort of intervention is at least feasible. We recommend that similar studies measure psychiatric morbidity during treatment and at follow-up, rather than immediately after finishing, when reactions to this termination are prominent.  相似文献   
992.
The effect of the novel 1,4-dihydronaphthyridine Ca2+ channel inhibitor Goe 5438 (CI-951) on voluntary ethanol consumption was examined in selectively bred alcohol-preferring (P) rats in a free choice two bottle preference test versus water. Intraperitoneally injected Goe 5438 dose-dependently (5, 10 or 20 µmol/kg, twice daily) inhibited ethanol and increased water intake over the 24 h period (injection day). The drug decreased ethanol preference, originally above 90%, by 6%, 19% and 45% at respective doses, on the injection day. That inhibitory effect of the highest dose of Goe 5438 on ethanol preference remained significant also on days 2 and 3 after injections (–51% and –18%, respectively). Goe 5438, in the highest dose, also tended to decrease granulated chow consumption during the injection day only. To further test whether the inhibition of ethanol preference is secondary to decrease in reinforcing properties of ethanol and not due to interference with satiety mechanisms, we compared the effect of two higher doses (10 and 20 µmol/kg, intraperitoneally, twice daily) of Goe 5438 on spontaneous preference for a non-caloric 0.04% saccharin solution in Sprague-Dawley rats. We observed a dose-dependent suppression of preference (by 44% and 58%, respectively) during the injection day, but not the subsequent 24 h period. However, Goe 5438 also significantly alleviated food pellet intake on the injection day. In conclusion, Goe 5438 produces potent and long-lasting inhibition of voluntary ethanol consumption, which may be secondary to attenuation of reinforcing properties of ethanol. Additionally, this particular Ca2+ channel inhibitor appears to have mild anorectic properties which may be conducive to acute suppression of alcohol intake.  相似文献   
993.
994.
995.
As part of a program to discover potent antihypertensive analogues of diltiazem (3a), we prepared 1-benzazepin-2-ones (4). Benzazepinones competitively displace radiolabeled diltiazem, and show the same absolute stereochemical preferences at the calcium channel receptor protein. Derivatives of 4 containing a trifluoromethyl substituent in the fused aromatic ring show potent and long-acting antihypertensive activity. Studies of the metabolism of 4 lead to the metabolically stable antihypertensive calcium channel blockers 5a and 5c. Benzazepinone 5a is a longer acting and more potent antihypertensive agent than the second generation diltiazem analogue TA-3090 (3e).  相似文献   
996.
Standard models for the analysis of repeated measurements assume a common response profile for all experimental units within a treatment group. However, in many applications this under-represents the nature of the response. There may be several distinct modes of response within a group (for example, responders versus non-responders to a given treatment), or there may be a set of distinct response profiles which are common to all the treatment groups. In these situations the effect of treatment can be characterized both by the shape of the fitted profiles and by estimating the proportion of cases who exhibit each particular response profile. This paper describes how such experiments may be analysed through the introduction of a latent variable into the standard model. Maximum likelihood estimation is straight-forward using the EM algorithm. Model choice requires some care, but good-fitting models can be identified via inspection of residuals and the use of empirical semi-variogram plots. Once the number of distinct profiles has been determined, treatment effects can be investigated using likelihood-ratio statistics. The approach is illustrated with a re-analysis of a dataset first described by Grizzle and Allen.  相似文献   
997.
Prophylactic administration of analgesics before surgery can decrease the intraoperative anaesthetic requirement and decrease pain during the early postoperative period. In a double-blind, placebo-controlled study involving 90 healthy ASA physical status I or II children undergoing bilateral myringotomy, we compared the postoperative analgesic effects of oral acetaminophen and ketorolac, when administered 30 min before induction of anaesthesia. Patients were randomized to receive saline (0.1 ml.kg-1), acetaminophen (10 mg.kg-1) or ketorolac (1 mg.kg-1) diluted in cherry syrup to a total volume of 5 ml. Anaesthesia was induced and maintained with halothane and nitrous oxide via a face mask. Postoperative pain was assessed by a blinded observer using an objective pain scale. The three study groups were similar with respect to demographic data, duration of anaesthesia and surgery, induction behaviour, oxygen saturation, incidence of postoperative emesis and, recovery times. The ketorolac group had lower postoperative pain scores and required less frequent analgesic therapy in the early postoperative period compared with the acetaminophen and placebo groups. In contrast, there were no differences in pain scores or analgesic requirements between the acetaminophen and the placebo groups. We conclude that the preoperative administration of oral ketorolac, but not acetaminophen, provided better postoperative pain control than placebo in children undergoing bilateral myringotomy.  相似文献   
998.
C White 《JAMA》1992,267(3):365; author reply 365-365; author reply 366
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999.
Using the rapid-response thermistor pulmonary artery catheter and transoesophageal echocardiography, this study examined the effects of 100 per cent oxygen, 70 per cent nitrous oxide/30 per cent oxygen, and 70 per cent nitrogen/30 per cent oxygen on the pulmonary circulation and ventricular function in ten patients with pulmonary hypertension. In comparison with baseline measurements, nitrous oxide administration resulted in small but statistically significant (P less than 0.05) changes in mean arterial pressure (76 +/- 14 to 67 +/- 12), mean pulmonary arterial pressure (37 +/- 14 to 33 +/- 13 mmHg), and cardiac output (3.7 +/- 1.4 to 3.2 +/- 1.1 L.min-1). Seventy per cent nitrogen resulted in no significant changes from baseline. The repeat 100 per cent oxygen measurements were nearly identical to the nitrous oxide measurements. It is concluded that nitrous oxide does not exacerbate pulmonary hypertension or ventricular dysfunction during high-dose fentanyl anaesthesia in patients with mitral valvular disease.  相似文献   
1000.
Background. Paragangliomas of the head and neck are slow-growing tumors that originate from neural crest cells. Between 7% and 9% of these tumors have a familial occurrence. The suspected gene for familial paragangliomas (FP) is transmitted with an autosomal dominant mode of inheritance with incomplete penetrance, and appears to exhibit genomic imprinting. It has been demonstrated by family studies that individuals who inherit the gene(s) from their father will develop the disease. Through linkage analysis, the gene(s) for FP has been postulated to be located on the long arm of chromosome 11. The discovery of many different genes has been elucidated through the cytogenetic analysis of affected individuals who carry specific chromosome aberrations. This project was designed to look for chromosome abnormalities in several second-generation family members to further assist in the localization of the gene(s) for FP. Methods. This study involved the cytogenetic evaluation of lymphocytes, fibroblasts, and tumor cells of several second-generation family members from a three-generation family with FP of the head and neck to look for chromosome abnormalities generally, and for abnormalities of chromosome 11 specifically. Standard cytogenetic techniques were used for lymphocyte and fibroblast cultures. Tumor cells were cultured in a collagen matrix with F12 medium supplemented with 3% L-glutamine and 10% fetal calf serum. Results. There were no detectable abnormalities of chromosome 11 in any of the cells. However, nonrandom abnormalities of chromosomes 5 and 7 were seen in some of the tumor cells of one FP patient. To our knowledge, this is the first article which demonstrated the ability to successfully culture FP of the head and neck. © 1995 Jons Wiley & Sons, Inc.  相似文献   
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