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We have evaluated the effects of a treatment with soluble interleukin-1 receptor (sIL-1R) in the accelerated model of autoimmune diabetes induced by cyclophosphamide (CY) in the non-obese diabetic (NOD) mouse. Prior to the CY challenge (350 mg/kg body weight), female euglycemic NOD mice were randomly divided into three groups (A–C). Groups B and C were treated daily from 1 day before to 13 days after the CY challenge with sIL-1R at doses of 0.2 and 2 mg/kg body weight. Group A was treated with PBS. By 2 weeks after CY administration, an acute form of autoimmune diabetes with glycosuria, hyperglycemia and severe insulitis occurred in the majority (13/20, 65%) of the control mice (group A). In contrast, repeated injections with sIL-1R protected NOD mice from insulin-dependent diabetes mellitus (IDDM) development in a dose-dependent fashion; the incidence of IDDM was 53.3% (8/15) in the mice treated with 0.2 mg/kg and only 6.7% (1/15) in those treated with 2 mg/kg. However, none of the doses of the sIL-1R reduced the extent of insulitis in NOD mice. Importantly, the anti-diabetogenic property of sIL-1R may not involve major T cell function impairment; accordingly, in parallel experiments, splenic lymphoid cells from NOD mice not challenged with CY, but treated with 2 mg/kg sIL-1R for 5 consecutive days showed a normal distribution of mononuclear cell subsets and maintained their capacity to secrete interferon-γ and IL-2 and to proliferate in response to polyclonal mitogenic stimulation with concanavalin A.  相似文献   
13.
The aim of this study was to locate in male pigs the sensory and autonomic ganglia innervating the retractor penis muscle (RPM), which was taken as an experimental model of the genital smooth musculature. The retrograde neuronal tracers horseradish peroxidase (HRP), Fast Blue (FB), and diamidino yellow (DY) were injected into the bulbopenile portion of the left RPM. The tracers highlighted a different affinity for the neuronal structures, although labelled cells supplying the RPM were generally found in bilateral dorsal root ganglia (DRGs, S1-S3), in bilateral paravertebral ganglia (PaGs, L2-S3), and in the left and right caudal mesenteric ganglia (CMGs). The mean number of labelled FB cells was 795 (range, 645-952) in DRGs, 16046.25 (range, 10226-18742) in PaGs, and 635.25 (range, 333-786) in CMGs. The mean diameter of pseudounipolar DRG cells was 60-75 microm, while the multipolar neurons of PaGs and CMGs had dimensions varying between 20-50 microm and 20-30 microm, respectively.  相似文献   
14.
Surface antigen negative hepatitis B virus (HBV) infection was evaluated in Venezuela, by molecular characterization of blood samples positive for antibodies to core antigen (anti-HBc) and negative for surface antigen (HBsAg) in blood donors (residual infections). HBV DNA was found in 11/258 samples (4.3%), and was significantly associated with high levels of anti-HBc antibodies (>25 UI/ml, P < 0.05), while no correlation was found between the presence of HBV DNA and the levels of anti-HBs. Synonymous and non-synonymous mutations were found in the HBV surface region (but not vaccine escape mutants) and in the precore/core region (precore mutants in 2/7 samples and 33-45 bp deletions near the N-terminal core region in 4/19 samples). While HBV genotype F prevails among HBsAg positive samples from blood donors in Venezuela, residual infection isolates were mainly genotypes A and D. Phylogenetic analysis of viral surface and core region revealed discrepancies in genotype designation in 6/9 samples, suggesting the presence of mixed infection or recombination. In conclusion, HBV residual infection in Venezuela does not seem to be frequently observed in HBV genotype F. This type of infection is frequently associated with variants exhibiting mutations in the surface gene that might be affecting the correct recognition by commercial tests, with precore mutants and with core internal deletions. These variants do not seem to cause severe liver disease, and on the contrary, were found circulating at low viremia.  相似文献   
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Background: On the basis of our previous experience, we designed this study to determine the activity and toxicity of outpatient treatment with autologous tumor-infiltrating lymphocytes (TIL) together with intermediate-dose recombinant interleukin-2 (rIL-2) and low-dose recombinant interferon alfa-2a (rIFN-2a), for patients with metastatic melanoma.Methods: Between April 1992 and October 1994, we processed 38 melanoma samples derived from 36 patients with metastases. Proliferative cultures of expanded lymphocytes (TIL) were infused only once into patients with metastatic melanoma. rIL-2 was administered subcutaneously for 1 month, starting on the day of TIL infusion, at an escalating dose of 6–18 × 106 IU/m2/day for the first week and at the maximum-tolerated dose for the subsequent 3 weeks and then, after a 15-day interval, for 1 week/month for 3 months. rIFN-2a was administered subcutaneously at 3 × 106 IU three times each week until progression.Results: Of 38 melanoma samples, 19 (50%) resulted in proliferative cultures and were infused. The median number of expanded lymphocytes was 18 × 109 (range, 1–43 × 109), and the median period of culture was 52 days (range, 45–60). rIL-2 was administered at doses ranging between 6 and 18 × 106 IU/m2/day. Toxicity was mild or moderate, and no life-threatening side effects were encountered. Two of 19 treated patients experienced complete responses of their metastatic sites (soft tissue), 10 had stable disease, and 7 showed progressive disease. The response rate was 11% (95% confidence interval, 2–35%).Conclusions: Outpatient treatment with TIL plus rIL-2 and rIFN-2a is feasible, although, within the context of the small sample size, the activity of the combination was no different from the reported activity of any of the components used alone.  相似文献   
17.
Two sets of benzotriazinone and benzoyltriazole derivatives were prepared and tested for local anaesthetic activity in comparison with lidocaine. Several of the prepared compounds exhibited a fairly good activity comparable or superior to that of lidocaine. The presence of a benzotriazinone or a benzoyltriazole moiety as an aromatic system was quite profitable for both the intensity and duration of activity. The acute toxicity in mice of the four most potent compounds of the series was also assessed. Compound 1b, which has an anaesthetic activity comparable to that of lidocaine, was also characterized by a more favourable therapeutic index. All compounds were tested in vitro to evaluate their negative chronotropic action in isolated rat right atria.  相似文献   
18.
We used in vitro autoradiography to identify the endothelin-1 receptor subtype(s) in the nucleus raphe obscurus of rats. These studies showed dense binding of [125I]PD151242 (for endothelin ETA receptors), while tissues incubated with [125I]BQ3020 (for endothelin ETB receptors) had low binding. In addition, we examined the effects of the endothelin receptor antagonists FR 139317 (endothelin ETA receptor-selective antagonist), SB 209670 (endothelin ETA/ETB receptor-non-selective antagonist) and BQ-788 (endothelin ETB receptor-selective antagonist) on the blood pressure responses following administration of endothelin-1 into the nucleus raphe obscurus. The basal mean arterial blood pressure (MABP) of the rats was 110 ± 7 mmHg (n = 5). This was decreased in a dose-dependent manner by endothelin-1 (0.1, 1 and 10 pmol) microinjected into the nucleus raphe obscurus. This effect occurred within 1–6 s and recovered within 4 ± 1.2 min at a dose of 10 pmol. The doses of 0.1 pmol and 1 pmol ET-1 had responses which lasted 1 ± 0.4 min and 2 ± 0.2 min, respectively. Small decreases in heart rate accompanied the MAP responses to endothelin-1. For instance, the heart rate decreased by 16 ± 4 beats min–1 after 10 pmol endothelin-1 (control, 366 ± 6 beats min–1, n = 5). Decreases in blood pressure induced by endothelin-1 were greatly reduced by pre-administration to the nucleus raphe obscurus of FR139317 (5 nmol/rat) or SB209670 (3 nmol/rat; 97 ± 7% and 95 ± 6%, P < 0.01, n = 5, respectively), but were not affected by BQ-788 (50 nmol/rat; 8 ± 3%, P > 0.05, n = 5). The antagonists did not influence heart rate when injected to the nucleus raphe obscurus prior to endothelin-1. FR139317 (0.5 nmol) and SB209670 (0.3 nmol) had no effects on endothelin-induced changes in arterial blood pressure. Therefore, the autoradiographic study showed that there are binding sites for ET-1 within the nucleus raphe obscurus of rats, which are predominantly of ETA type. The in vivo study showed that ETA receptors are the predominant mediators of depressor responses induced by endothelin-1 injected into this nucleus. Received: 6 August 1998 / Accepted: 16 February 1999  相似文献   
19.
Summary Benign mammary gross cystic disease is the most common breast lesion. Women with apocrine changes of epithelium lining the cysts are at higher risk for developing breast cancer than the normal female population. Sialic acid has drawn considerable interest because of carbohydrate aberrations in malignant cells. The current investigation determined the concentrations of lipid-associated sialic acid (LASA) in 62 breast cyst fluids and sera. Data analyses show a significant increase in the mean values of LASA in metabolically active apocrine cysts when compared to the cysts with Na+/K+>3 (flattened cysts) (p<0.001). The greater LASA levels in cyst fluids with lower intracystic Na+/K+ ratios could represent an altered expression of biosynthetic activity of the surrounding apocrine cell surface sialoglycolipid metabolism, providing a possible explanation of why women with apocrine cysts may be at greater cancer risk and being useful in further studies on functional stage changes in the cysts and their relationship to breast cancer.  相似文献   
20.
目的 探讨重组人白细胞介素 6(rhIL 6)对NOD小鼠自发性和环磷酰胺 (CY)诱发性Ⅰ型糖尿病 (IDDM)的影响及相关机制。方法 通过观察NOD小鼠用药后血糖和尿糖水平、胰腺组织病理学特征 ,及血清抗CD3抗体、LPS诱导的炎症因子IFN γ、TNF α水平的变化 ,以及CY诱导ID DM发生率 ,确定rhIL 6的抗IDDM作用。结果  4wk龄♀NOD小鼠连续注射rhIL 6 1 6wk后 ,胰岛炎即胰腺淋巴细胞、单核细胞浸润明显减少 ,糖尿病的发病率明显降低(33 % )。与空白对照组相比 ,血清中炎症因子IFN γ、TNF α水平也呈显著的下降趋势。 1 2wk龄NOD小鼠连续 8wk应用rhIL 6 ,糖尿病发生率则无明显变化 ,且实验中未观察到rhIL 6对CY诱发IDDM的保护作用。结论 rhIL 6早期预防用药可降低NOD小鼠自发性IDDM的发生 ,该保护作用可能与其降低炎症因子TNF α、IFN γ分泌有关  相似文献   
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