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61.
The purpose of this work was to study the usefulness of short muscular exercise as part of standard respiratory function testing. A group of 19 patients with chronic bronchitis performed moderate load exercise (30 to 60 watts) on a cycle ergometer for 10 mn. Blood gases and acid-base balance were measured at rest, at the 2nd and the 10th mn of pedaling. In spite of highly significant relationships between resting values (blood gases, spirometry) and exercise data (blood gases), the scattering of the results precludes predicting the latter from the former. In contrast, the comparison between each of the two exercise results (2nd and 10th mn) shows not only a highly significant correlation but also a standard deviation to the regression lines which is objectively diminished. Thus, muscular exercise seems to give specific information that could be a useful component of respiratory function testing. Further, blood gas results obtained at the 2nd mn of muscular exercise suffice, thus obviating the need for a longer exercise programme that might be badly tolerated by patients.  相似文献   
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This prospective trial aimed to evaluate the therapeutic effects and systemic toxicities of capecitabine monotherapy and capecitabine treatment combined with biological response modifiers in patients with metastatic renal cell carcinoma. Fifty-four patients suffering from metastatic renal cell carcinoma progressing under first-, second- or third-line treatment entered the trial. Capecitabine was given orally at a dose of 2500 mg/m2 daily divided into two doses for 14 days, followed by a 7-day rest in the monotherapy as well as in the combination treatment. This schedule was repeated in 3-week cycles. The combination therapy consisted of capecitabine and an immunotherapy treatment, which consisted either of interferon (IFN)-gamma1b (100 mg/day) administered consecutively 5 times weekly during weeks 1 and 2, and recombinant interleukin (IL)-2 (4.5 MU/day) administered on 4 consecutive days during weeks 3 and 4, every 6 weeks, or IFN-alpha (6 MioIE/day) administered 3 times a week. Fifty-two patients are now evaluable for response and 54 patients for toxicity. We observed a partial response to treatment in five patients (9.6%), minor response in five patients (9.6%), stable disease in 32 patients (61.6%) and only 10 patients (19.2%) showed continued disease progression despite treatment. Outpatient capecitabine was well tolerated. We did not observe any WHO grade IV toxicities. We conclude that capecitabine monotherapy and capecitabine treatment in combination with biological response modifiers appear to be effective regimens with favorable toxicity profiles in patients with advanced renal cell carcinoma. Capecitabine monotherapy seems to be superior than the combination treatment because of its easier application form.  相似文献   
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Chemotherapy- and radiotherapy-induced oral mucositis represents a therapeutic challenge frequently encountered in cancer patients. This side effect causes significant morbidity and may delay the treatment plan, as well as increase therapeutic expenses. The pathogenesis of this debilitating side effect can be attributed to the direct mucosal toxicity of cytotoxic agents and ionizing radiation and to indirect mucosal damage caused by a concomitant inflammatory reaction exacerbated in the presence of neutropenia, and the emergence of bacterial, mycotic, and viral infections. The prophylactic and therapeutic armamentarium for the treatment of oral mucositis consists of locally and systemically applied nonpharmacological measures and pharmacotherapeutics.  相似文献   
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本文研制了以四苯硼—唐松草新碱缔合物为电活性物质的变价态唐松草新碱—PVC膜电极。电极膜按电活性物质:PVC:DBP为1:8:8组成。该电极在pH 5.0~6.0,Ⅰ=0.05的NaCl—HCl溶液中Nernst响应范围为1×10-3~1×10-5mol/L。电极斜率为58.2 mV/logc。检测限为2.5×10-6mol/L。用直接电位法考察了TDH+,TDH2CF++共存时溶液pH和电极斜率S的关系。用S—pH关系,测定了25℃,Ⅰ=0.05时的Ka1值为(2.5±0.2)×10-4,用E—pH关系,测定了25℃,Ⅰ=0.05时的Ka2值为(8.1±0.9)×10-8。  相似文献   
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In search of a functional immunological defect in patients with hemophilia A, we investigated the early phase of the immune response and found a deficiency in the monocyte-T cell interaction after in vitro exposure to a bacterial antigen. T-cell proliferation in response to Escherichia coli-pulsed autologous monocytes was significantly (P less than 0.025) reduced in hemophiliacs [mean dpm +/- SEM (n = 25): 9036 +/- 2600] as compared to healthy controls [mean dpm +/- SEM (n = 24): 17,812 +/- 2985]. This functional defect was expressed in a severe form (antigen-induced monocyte-T cell interaction less than or equal to 2000 dpm) in both HTLV III antibody-positive and -negative patient populations. Significantly decreased T-helper/T-suppressor-cell ratios (mean dpm +/- SEM: patients 1.47 +/- 0.13; controls 2.04 +/- 0.11; P less than 0.001)--but without a concomitant reduction in the absolute number of T-helper cells--could also be observed.  相似文献   
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Effects of leflunomide on immune responses and models of inflammation   总被引:11,自引:0,他引:11  
Conclusions Leflunomide is an antiphlogistic and immunomodulating agent that has been shown to be effective in preventing and healing autoimmune disorders and reactions leading to organ graft rejection. From our preliminary clinical data [4], we now have hopes that these effects, observed in experimental animals, can truly be transferred to humans.Although we are far from understanding the mode of action of leflunomide, we are slowly gathering some insight. A good many of the immunosuppressive effects of leflunomide can be attributed to the antagonistic effects it has on responses to many cytokines, most likely through receptor expression and signal transduction (tyrosine kinase inhibition). The inhibition of transplant rejection could be explained by interference with the activity of IL-2 and IL-4, i.e. the interference of cytotoxic T cell formation. Considering, further, that increased IL-3-like activity has been reported in autoimmune MRL/lpr mice [23], and that it is felt that this amplified activity may contribute to the pathology of their illness [23], then the interference of leflunomide with IL-3 may, together with the antagonistic activity of TRF and specifically IL-4, explain some of the disease modifying properties of this drug in animals with SLE-like and other autoimmune diseases. Also, interference with responses to IL-6 (Germann, personal communication) could be responsible for the suppression of acute-phase proteins observed in adjuvant-diseased rats [24].Our data concerning tyrosine kinase inhibition as a hypothetical mechanism for the non-cytotoxic and reversible antiproliferative activity of A77 1726 are in many ways, intriguing. First of all, many known receptors for growth factors are associated with tyrosine kinase, i.e. EGF [35], IL-2 (the high binding, 75 kDa chain) [21], IL-3 [26], G-CSF, GM-CSF and TNF- [9]. Leflunomide antagonizes all of these mediators. On the other hand, IL-1, which is not antagonized by leflunomide, is not associated with tyrosine kinase, but with threonine and serine kinase [11]. Much more work must be conducted before we can be sure that tyrosine kinase inhibition is important for the mode of action of leflunomide.Another important aspect of this drug is its inhibitory effect on the release of histamine from basophils and mast cells, because of its role in inflammatory reactions. Relating to our findings on the activity of leflunomide on murine SLE-like disorders, it has been reported recently that SLE patients often exhibit abnormal production of antibodies to IgE, and that these autoantibodies may, by activating mast cells and basophils, play a consequential part in the release of vasoactive amines, thus leading to generalized tissue injury [15].We are confident that leflunomide will prove to be an effective drug in combating human autoimmune disorders. Indeed, we already have preliminary evidence for this, from studies of its effects on humans suffering from autoimmune diseases. Moreover, this drug provides a tool for gaining new insights into both the mechanisms leading to such ailments and their therapeutic control, and as such may facilitate the discovery of even more proficient drugs or other means to modulate these malfunctioning immune reactions.  相似文献   
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The aim of this study was to investigate the effects of 8 weeks of moderate restriction of time in bed (TIB) on glucose tolerance and insulin sensitivity in healthy older self-reported long sleepers. Forty-two older adults (ages 50-70 years) who reported average sleep durations of >or=8.5 h per night were assessed. Following a 2-week baseline, participants were randomly assigned to two 8-week treatments: either (i) TIB restriction (n = 22), which involved following a fixed sleep schedule in which time in bed was reduced by 90 min compared with baseline; (ii) a control (n = 18), which involved following a fixed sleep schedule but no imposed change of TIB. Sleep was monitored continuously via wrist actigraphy recordings, supplemented with a daily diary. Glucose tolerance and insulin sensitivity were assessed before and following the treatments. Compared with the control treatment, TIB restriction resulted in a significantly greater reduction of nocturnal TIB (1.39 +/- 0.40 h versus 0.14 +/- 0.26 h), nocturnal total sleep time (TST) (1.03 +/- 0.53 h versus 0.40 +/- 0.42 h), and 24-h TST (1.03 +/- 0.53 h versus 0.33 +/- 0.43 h) from baseline values. However, no significant effect of TIB restriction was found for glucose tolerance or insulin sensitivity. These results suggest that healthy older long sleepers can tolerate 8 weeks of moderate TIB restriction without impairments in glucose tolerance or insulin sensitivity.  相似文献   
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