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171.
The effects of anabolic steroid use on male sexual behavior were assessed using a structured clinical interview administered to male body builders currently using steroids, and to two comparison groups (body builders with a past but not current history of steroid use, and a group of natural body builders who had never used steroids). Current anabolic steroid users had a significantly higher coital and orgasmic frequency than did comparison athletes. They also reported a significantly higher incidence of erectile difficulties during the past month. Beliefs concerning the sexually stimulating effects of steroids did not correlate with the frequencies of specific sexual behaviors. The data support the contention that anabolic steroids, as androgenic compounds, enhance sexual desire.  相似文献   
172.
Starting in July 1985, the Gynecologic Oncology Group conducted a series of phase II trials with ifosfamide/mesna in advanced or recurrent gynecologic malignancies. Previously untreated patients received 1.5 g/m2 i.v. ifosfamide daily for 5 days. Mesna was given i.v. q4h×3 following ifosfamide; each dose was 20% of the daily ifosfamide dose. All patients with ovarian and 87% of those with cervical cancer had previously undergone platinum-based therapy. Because of the toxicity encountered in previously treated patients with ovarian carcinoma, the dose of ifosfamide was reduced to 1.2 g/m2 daily in all patients who had received prior chemo- or radiotherapy. In epithelial ovarian carcinoma, responses were observed in 8 (20.0%) of 41 evaluable patiens, with 3 (7.0%) complete responses. Response duration was 2.1–20.3+ months, with a median of 6.9+ months. In squamous-cell carcinoma of the cervix, 3 (11.1%) of 27 evaluable patients showed partial responses of 1.8, 2.2, and 3.1 months' duration. Of 26 untreated patients with mixed mesodermal tumors of the uterus, 5 (19.2%) achieved complete and 3 (11.5%) showed partial responses, for an overall response rate of 30.7%. Response duration was 1.4+-8.6 months, with a median of 3.8 months. Toxicity included two deaths due to renal insufficiency and a third related to neurologic impairment. Hematologic toxicity was manageable. Ifosfamide/mesna has activity in a wide range of gynecologic malignancies.Presented at the Satellite Symposium Ifosfamide in Gynecological Tumors of the 5th European Conference on Clinical Oncology and Cancer Nursing, London, September 3–7, 1989  相似文献   
173.
The possible interrelationships between the effects of dietary selenium and perfluorodecanoic acid (PFDA) on growth and lipid metabolism were studied in the male Sprague Dawley rat. Rats were divided into groups and placed on diets containing three levels of selenium (0.04, 0.2, and 1.0 ppm as sodium selenite). Two weeks later, half the rats in each group received a single 35 mg/kg IP injection of PFDA in corn oil, while their pair-fed companion received only vehicle. Rats injected with PFDA stopped gaining weight, and weighed less than pair-fed controls, despite equal food intakes. Two weeks following PFDA administration the rats were killed and plasma cholesterol and triglycerides, and liver peroxisomal enzyme activities were quantified. In contrast to other peroxisome proliferators, PFDA increased plasma triglycerides while decreasing plasma cholesterol. The rate of peroxisomal fatty acid -oxidation was decreased, even though the activity of fatty acyl-CoA oxidase, the first enzyme in the peroxisomal fatty acid -oxidation pathway, was increased. Dietary selenium, other than increasing the liver to body weight ratio, did not alter growth or lipid metabolism. This study demonstrates, for the first time, the existence of a non-hypotriglyceridemic peroxisome proliferator-PFDA.  相似文献   
174.
Demographic, drug use and criminal correlates of risky drug practices were examined among 279 detained youth in NSW Juvenile Justice Centres. Binge drinking was common, with 63% reporting the consumption of at least five drinks in a row in the 2 weeks prior to incarceration. It was associated with being older, being from an English-speaking background, regular tobacco consumption and having a current drug problem. A quarter (24%) of the sample had injected an illicit drug, over one-third (37%) of whom also reported sharing needles. Injectors were more likely to be polydrug users, regular amphetamine users and have a past history of drug treatment. While 16% of the sample indicated a need for drug treatment, only 10% were currently receiving some form of treatment, most commonly counselling. Appropriate strategies are needed among this population to address gaps in treatment provision.  相似文献   
175.
176.
Second part of an item featuring action research with four different trusts to investigate factors relating to the implementation of the local pay policy. Describes methodologies used, such as clinical team diagnosis and cognitive mapping. Looks at the way forward, listing critical factors in ensuring successful implementation.  相似文献   
177.
Antithymocyte globulin (ATG) and muromonab CD3 (OKT3) are currently the only antilymphocyte preparations that are commercially available for induction immunosuppressive therapy for renal allograft transplantation in the US. ATG, in the usually prescribed doses, is more expensive than muromonab CD3, but muromonab CD3 is associated with more severe adverse effects that may affect clinical outcome and overall cost. We performed a retrospective study of all adult recipients of a first cadaveric renal allograft, who underwent transplantation between January 1991 and December 1994 who received either ATG (n = 92) or muromonab CD3 (n = 91) for induction therapy at our transplant centre. The average age of recipients was older (50 vs 44 yrs; p = 0.001) and extended donors were more commonly used in the ATG group (41 vs 13%; p = 0.0001) compared with the muromonab CD3 group. Nevertheless, at 1 year post-transplant, the incidence of rejection was lower (34 vs 47%) and graft survival was better (93 vs 85%; p = 0.03) in the ATG group. Patients who received ATG were discharged earlier (9.4 vs 13.3 days; p = 0.0001) and had similar serum creatinine levels on the day of discharge (2.4 +/- 1.5 vs 2.1 +/- 1.1 mg/dl; p = 0.25). Overall, the 1-year hospitalisation costs of transplantation and readmissions were similar [$US39,937 +/- 17,014 vs $US42,850 +/- 20,923 (currency year 1994); p = 0.22]. This is the first comparison of ATG and muromonab CD3 in renal transplant recipients to consider clinical as well as economic outcomes. For renal transplant patients in whom induction therapy is used at our centre, the initial expense of ATG can be justified by improved graft survival, fewer rejection episodes, and shorter hospital stays, which are associated with similar overall transplantation costs.  相似文献   
178.
  1. The radiolabelled bicyclic dinitrile, [3H]-3,3-bis-trifluoromethyl-bicyclo[2.2.1]heptane-2,2-dicarbonitrile ([3H]-BIDN), exhibited, specific binding of high affinity to membranes of the southern corn rootworm (Diabrotica undecimpunctata howardi) and other insects. A variety of γ-aminobutyric acid (GABA) receptor convulsants, including the insecticides heptachlor (IC50, 35±3 nM) and dieldrin (IC50, 93±7 nM), displaced [3H]-BIDN from rootworm membranes. When tested at 100 μM, 1-(4-ethynylphenyl)-4-n-propyl-2,6,7-trioxabicyclo[2.2.2]octane(EBOB), 4-t-butyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-1-thione (TBPS), 1-phenyl-4-t-butyl-2,6,7-trioxabicyclo[2.2.2]octane (TBOB) and picrotoxin failed to displace 50% of [3H]-BIDN binding to rootworm membranes indicating that the bicyclic dinitrile radioligand probes a site distinct from those identified by other convulsant radioligands.
  2. Dissociation studies showed that dieldrin, ketoendrin, toxaphene, heptachlor epoxide and α and β endosulphan displace bound [3H]-BIDN from rootworm membranes by a competitive mechanism.
  3. Rat brain membranes were also shown to possess a population of saturable, specific [3H]-BIDN binding sites, though of lower affinity than in rootworm and with a different pharmacological profile. Of the insecticidal GABAergic convulsants that displaced [3H]-BIDN from rootworm, cockroach (Periplaneta americana) and rat brain membranes, many were more effective in rootworm.
  4. Functional GABA-gated chloride channels of rootworm nervous system and of cockroach nerve and muscle were blocked by BIDN, whereas cockroach neuronal GABAB receptors were unaffected.
  5. Expression in Xenopus oocytes of either rat brain mRNA, or cDNA-derived RNA encoding a GABA receptor subunit (Rdl) that is expressed widely in the nervous system of Drosophila melanogaster resulted in functional, homo-oligomeric GABA receptors that were blocked by BIDN. Thus, BIDN probes a novel site on GABA-gated Cl channels to which a number of insecticidally-active molecules bind.
  相似文献   
179.
Levels of intracellular glutathione (GSH) and the GSH-related enzymes -glutamylcysteine synthetase (-GCS) and -glutamyltranspeptidase (-GT) were measured in the melphalan-resistant human multiple myeloma cell line 8226/LR-5 and were compared to those measured in the drug-sensitive 8226/S and doxorubicin-resistant 8226/Dox40 cell lines. Both GSH and -GCS activity, the rate-limiting step in the de novo synthesis of GSH, were elevated by a factor of approximately 2 in the melphalanresistant 8226/LR-5 cells relative to the other two lines. -GT activity was not elevated significantly in the /LR-5 cells. Northern analysis with a probe specific for the large subunit of human liver -GCS identified two bands (3.2 and 4.0 kb), both of which were increased by a factor of 2–3 in the 8226/LR-5 line. Levels of -GCS mRNA expression were comparable in the /S and /Dox40 cell lines. Levels of -GT mRNA were similar in the /S and /LR-5 lines but were reduced in the /Dox40 cells. These data suggest that the increased GSH levels associated with resistance to melphalan in the 8226/LR-5 myeloma cells is attributable to up-regulation of -GCS. This observation is consistent with recent demonstrations of up-regulation of -GCS in melphalan-resistant prostate carcinoma cells and cisplatinum-resistant ovarian carcinoma cells, suggesting that increased expression of -GCS may be an important mediator of GSH-associated resistance mechanisms.  相似文献   
180.
Cytogenetic studies in squamous cell carcinoma of the head and neck (SCCHN) have identified a clustering of breakpoints in a number of chromosomes, including chromosome 3. We have undertaken a loss of heterozygosity analysis (LOH) of 36 SCCHN and six solid tumours which were not squamous cell, and their respective normal specimens, using a bank of microsatellite markers, with the aim of identifying specific sites of frequent loss on chromosome 3. The analysis was undertaken with 12 microsatellite markers, 10 of which are on the p arm of chromosome 3. Allelic loss greater than 10% was seen at four sites; D3S1269 (13%), D3S1079 (23%), D3S659 (23%) and D3S1293 (31%). None of this series of tumours showed loss of the whole chromosome, however 47% of the tumours analysed had LOH at one or more loci. The highest incidence of LOH was found at D3S1293 in the 3p24-p25 region. The second highest region with LOH was found at D3S1079 and D3S659 at 3p13. The remaining markers telomeric and centromeric to these two regions were found to have a LOH of less than 10%. Furthermore, we found a strong association between loss of one marker on chromosome 3 in these SCCHN and poor clinical prognostic indicators; such as site, pathological differentiation, positive nodes at pathology (p<0.05) and TNM status (p<0.05). This study has identified two regions in SCCHN that are most likely to be important in the development of squamous cell carcinoma of the head and neck at 3p24-p25 and 3p13 and may indicate sites of novel tumour suppressor genes in this disease.  相似文献   
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