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41.
OBJECTIVE: The purpose of this study was to describe the sociodemographic and serologic profiles in a first time consultant population at the Information and AIDS Prevention Center of Valencia (Spain). In addition, the HIV infection risk factors were analyzed. METHOD: A cross-sectional study was performed on 1,573 persons who consulted during the year 1995. Sociodemographic and infection risk practices data were recorded and serologic information about HIV, HBV and HCV infection were obtained. Exact binomial method with a 95% interval confidence was used to calculate infection prevalence and the chi square test to make comparisons between qualitative variables. RESULTS: Sex distribution was 66,1% males and 31,9% females; mean age was 29,01 (SD: 9.2) years. Sexual intercourse without condom (25.2%) and parenteral drug abusers (22.6%) were the more frequent risk groups seeking consultation about HIV infection. Global HIV infection prevalence was 12.7% (95% CI= 11,2-14,5%). Among HIV seropositive patients, sexual transmission accounted for 30.8% of cases, of which 69.4% were heterosexual relations. The HIV infection prevalence for different risk groups were the following: parenteral drug abusers 36.8% (95% CI= 31,7-42%), heterosexual intercourse with an HIV-infected partner 24.1% (95% CI= 17,1-32,2%) and homosexual intercourse between men 9,5% (95% CI= 5,8-14,5%). HCV antibody prevalence for parenteral drug abusers was 81.2% (95% CI= 76,7-85,1%). Risk practices with a statistically significant association with HIV infection were: being an injecting drug abuser, as well as having an HIV infected and/or a injecting drug abuser partner. CONCLUSIONS: Drug parenteral abusers are still the target population for prevention programs. Data suggest that prevention and sexual education programs must continue. The main effort should be focused on the young population and on sexual partners of injecting drug abusers and/or HIV seropositive partners.  相似文献   
42.
1. A study is made of the contractile and relaxant effects, and mechanism of action, of histamine on isolated uterus from mice treated with diethylstilboestrol, employing acetylcholine and adrenaline as contractile and relaxant standard agents. 2. Concentration-response curves for histamine agonists were obtained in the absence and presence of selective histaminergic blocking drugs (clemizole, ranitidine and thioperamide) and indomethacin. A number of experiments were carried out in uterus from reserpinised mice. Concentration-response curves for acetylcholine and adrenaline were also obtained in the absence and presence of their selective antagonist (atropine and propranolol). 3. In isolated oestrogenised mouse uterus, histamine and acetylcholine produced a concentration-related contractile response. When the uterus was precontracted with KCl, histamine at lower doses produced a slight contraction, though in the presence of clemizole it induced concentration-related relaxation, reminiscent of that produced by adrenaline. Atropine and propranolol antagonised the contractile and relaxant effects of acetylcholine and adrenaline, respectively. 4. In isolated uterus from reserpinised mice, histamine and 2-pyridylethylamine, but not 4-methylhistamine, produced a concentration-related contractile response. Ranitidine potentiated the contractile effect of histamine, though clemizole--in the presence of ranitidine--competitively antagonised the contractile effect of histamine (pA2 = 10.50 +/- 0.81). The concentration-relaxant curve of histamine in the presence of clemizole was not modified by ranitidine or indomethacin, but shifted to the right with thioperamide. The same displacement was also observed in the presence of clemizole plus ranitidine. 5. In mouse isolated uterus, histamine mainly produced contraction mediated by histamine H1-receptors, though the existence of histamine H2- or H3-receptors mediating relaxation could not be excluded.  相似文献   
43.
Gonadal steroid hormones influence vascular tone and the development of hypertension. There are sex differences in the incidence of cardiovascular diseases, and great attention has been placed on the study of estrogen cardiovascular effects. However, there are only a few reports on the effects of testosterone on the vasculature. It is commonly accepted that the mechanism of the action of steroid hormones on target tissues is mediated through the binding of hormones to cytoplasmic or nuclear receptors. However, some studies indicate that steroid action can be extremely rapid and therefore unlikely to be through a genomic mechanism. The purpose of this study was to assess the effect of intravascularly confined testosterone on an isolated rat heart to demonstrate acute and possibly nongenomic effects of the steroid. Our results show that testosterone blocked the adenosine vasodilator effect and increased vascular resistance, even when its presence was restricted to the coronary vascular lumen. These effects were exerted rapidly and possibly through nongenomic mechanisms.  相似文献   
44.
BACKGROUND: The basolateral isoform of the Na(+):K(+):2Cl(-) cotransporter is expressed in several epithelial and non-epithelial cells, in which it is involved in ion secretion processes and in cell volume regulation. In humans, this cotransporter has been implicated in the development of primary hypertension. The major goal of the present study was to characterize the effect of protein kinase C activation on the function of the Na(+):K(+):2Cl(-) cotransporter isoform present in Xenopus laevis oocytes. METHODS: Oocytes were surgically harvested from adult female Xenopus laevis frogs, defolliculated by incubation in frog ringer containing collagenase B (2 mg/mL) under vigorous shaking, and by hand under the microscope. Only stage V-VI oocytes were used in the study. After overnight incubation in regular frog Ringer, oocytes were switched to a Cl(-)-free ringer for at least 12 h before beginning uptake experiments. The function of the Na(+):K(+):2Cl(-) cotransporter was determined by assessing tracer 22Na(+) uptake in the control group as well as under several experimental conditions, such as changes in extracellular osmolarity, absence of one of the cotransported ions, or the presence of drugs such as the specific cotransporter inhibitor bumetanide, phorbol esters (TPA, PDBu, or 4alphaPDD), and the PKC inhibitor bisindolylmaleimide I. At the end of the uptake period, tracer Na(+) uptake was counted by liquid scintillation of each individual oocyte previously dissolved in SDS. RESULTS: Xenopus oocytes exhibited a bumetanide-sensitive Na(+):K(+):2Cl(-) cotransporter in the plasma membrane activated by hypertonicity and inhibited by hypotonicity. The bumetanide-sensitive fraction of Na(+) uptake was significantly reduced by the addition of phorbol esters TPA or PDBu to the uptake media. This inhibitory effect of PKC activators was dose- and time-dependent. Phorbol ester 4alphaPDD, which cannot activate PKC, exhibited no effect on Na(+):K(+):2Cl(-) cotransporter function. In addition, pretreatment of oocytes with the PKC inhibitor bisindolylmaleimide I partially abolished TPA-induced reduction in the cotransporter function. CONCLUSION: In defolliculated Xenopus laevis oocytes, phorbol esters reduce the function of the Na(+):K(+):2Cl(-) cotransporter by a mechanism that includes the activation of an endogenous PKC.  相似文献   
45.
Purpose: Our purpose was to detect aneuploidy for chromosomes 13, 16,18, 21, 22, X, and Y in preimplantation embryos from patients with a history of unexplained recurrent miscarriage. Methods: Three patients with a history of unexplained recurrent spontaneous abortion were included in this study. Embryos were biopsied at the eight-cell stage, individually fixed on slides, and processed for fluorescent in situ hybridization (FISH). A multiple FISH protocol for seven chromosomes pairs (13, 16, 18, 21, 22, X, and Y) has been developed. Results: A total of 39 embryos was studied with the multiple FISH protocol developed. Successful analysis of the biopsied embryos was achieved within the time limits usually allowed in a preimplantation diagnosis program. Analysis of the blastomeres showed that 17 embryos were chromosomally normal for the probes used, 16 embryos were aneuploid, and in 6 embryos no informative results were obtained. Conclusions: In the patients studied, a large proportion of embryos (41%) exhibited chromosomal abnormalities for the probes used. Preimplantation diagnosis to screen for chromosome abnormalities could be a feasible approach to improve the possibility of successful pregnancy in these couples.  相似文献   
46.
We studied the synergistic effects of pergolide and bromocriptine with caffeine on turning behavior in 6-OHDA denervated rats. Both pergolide and bromocriptine were synergistic with caffeine, and prevented tolerance to caffeine-induced turning. When caffeine was removed, tolerance to bromocriptine effects was observed for 1 day only, while no tolerance was observed to pergolide. These results suggest that caffeine could be useful in the treatment of Parkinson's disease, preferentially as an adjuvant of mixed dopaminergic agonists like pergolide.  相似文献   
47.
BACKGROUND: The aim of this study was to determine whether the response rate for the paclitaxel-carboplatin combination is superior to carboplatin alone in the treatment of patients with platinum-sensitive recurrent ovarian carcinoma. PATIENTS AND METHODS: Patients with recurrent ovarian carcinoma, 6 months after treatment with a platinum-based regimen and with no more than two previous chemotherapy lines, were randomized to receive carboplatin area under the curve (AUC) 5 (arm A) or paclitaxel 175 mg/m(2) + carboplatin AUC 5 (arm B). The primary end point was objective response, following a 'pick up the winner' design. Secondary end points included time to progression (TTP), overall survival, tolerability and quality of life (QoL). RESULTS: Eighty-one patients were randomized and included in the intention-to-treat analysis. The response rate in arm B was 75.6% [26.8% complete response (CR) + 48.8% partial response (PR)] [95% confidence interval (CI) 59.7% to 87.6%] and 50% in arm A (20% CR + 30% PR) (95% CI 33.8% to 66.2%). No significant differences were observed in grade 3-4 hematological toxicity. Conversely, mucositis, myalgia/arthralgia and peripheral neurophaty were more frequent in arm B. Median TTP was 49.1 weeks in arm B (95% CI 36.9-61.3) and 33.7 weeks in arm A (95% CI 25.8-41.5). No significant differences were found in the QoL analysis. CONCLUSIONS: Paclitaxel-carboplatin combination is a tolerable regimen with a higher response rate than carboplatin monotherapy in platinum-sensitive recurrent ovarian carcinoma.  相似文献   
48.
49.
There is currently a great interest in delayed chromosomal and other damaging effects of low-dose exposure to a variety of pollutants which appear collectively to act through induction of stress-response pathways related to oxidative stress and ageing. These have been studied mostly in the radiation field but evidence is accumulating that the mechanisms can also be triggered by chemicals, especially heavy metals. Humans are exposed to metals, including chromium (Cr) (VI) and vanadium (V) (V), from the environment, industry and surgical implants. Thus, the impact of low-dose stress responses may be larger than expected from individual toxicity projections. In this study, a short (24 h) exposure of human fibroblasts to low doses of Cr (VI) and V (V) caused both acute chromosome damage and genomic instability in the progeny of exposed cells for at least 30 days after exposure. Acutely, Cr (VI) caused chromatid breaks without aneuploidy while V (V) caused aneuploidy without chromatid breaks. The longer-term genomic instability was similar but depended on hTERT positivity. In telomerase-negative hTERT- cells, Cr (VI) and V (V) caused a long lasting and transmissible induction of dicentric chromosomes, nucleoplasmic bridges, micronuclei and aneuploidy. There was also a long term and transmissible reduction of clonogenic survival, with an increased beta-galactosidase staining and apoptosis. This instability was not present in telomerase-positive hTERT+ cells. In contrast, in hTERT+ cells the metals caused a persistent induction of tetraploidy, which was not noted in hTERT- cells. The growth and survival of both metal-exposed hTERT+ and hTERT- cells differed if they were cultured at subconfluent levels or plated out as colonies. Genomic instability is considered to be a driving force towards cancer. This study suggests that the type of genomic instability in human cells may depend critically on whether they are telomerase-positive or -negative and that their sensitivities to metals could depend on whether they are clustered or diffuse.  相似文献   
50.
The San Carlos Gestational Diabetes Mellitus (GDM) prevention study, a nutritional intervention RCT based on a Mediterranean Diet (MedDiet), has been shown to reduce the incidence of GDM. The objective of this study is to investigate the relationship of leptin, adiponectin, interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-α), insulin and HOMA-IRand circulating miRNAs (miR-29a-3p, miR-103a-3p, miR-132-3p, miR-222-3p) with the appearance of GDM and with MedDiet-based nutritional intervention, at 24–28 gestational weeks (GW), and in glucose regulation 2–3 years post-delivery (PD). A total of 313 pregnant women, 77 with GDM vs. 236 with normal glucose tolerance (NGT), 141 from the control group (CG, MedDiet restricting the consumption of dietary fat including EVOO and nuts during pregnancy) vs. 172 from the intervention group (IG, MedDiet supplemented with extra virgin olive oil (EVOO) and pistachios during pregnancy) were compared at Visit 1 (8–12 GW), Visit 2 (24–28 GW) and Visit 3 (2–3 years PD). Expression of miRNAs was determined by the Exiqon miRCURY LNA RT-PCR system. Leptin, adiponectin, IL-6 and TNF-α, were measured by Milliplex® immunoassays on Luminex 200 and insulin by RIA. Women with GDM vs. NTG had significantly higher leptin median (Q1–Q3) levels (14.6 (9.2–19.4) vs. 9.6 (6.0–15.1) ng/mL; p < 0.05) and insulin levels (11.4 (8.6–16.5) vs. 9.4 (7.0–12.8) µUI/mL; p < 0.001) and lower adiponectin (12.9 (9.8–17.2) vs. 17.0 (13.3–22.4) µg/mL; p < 0.001) at Visit 2. These findings persisted in Visit 3, with overexpression of miR-222-3p (1.45 (0.76–2.21) vs. 0.99 (0.21–1.70); p < 0.05)) and higher levels of Il-6 and TNF-α. When the IG is compared with the CG lower levels of insulin, HOMA-IR-IR, IL-6 levels at Visit 2 and 3 and leptin levels only at Visit 2 were observed. An overexpression of miR-222-3p and miR-103a-3p were also observed in IG at Visit 2 and 3. The miR-222-3p and miR103a-3p expression correlated with insulin levels, HOMA-IR, IL-6 and TNF-α at Visit 2 (all p < 0.05). These data support the association of leptin, adiponectin and insulin/HOMA-IR with GDM, as well as the association of insulin/HOMA-IR and IL-6 and miR-222-3p and miR-103a-3p expression with a MedDiet-based nutritional intervention.  相似文献   
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