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91.
B.J. Lipworth R. A. Clark D. G. McDevitt 《Journal of clinical pharmacy and therapeutics》1991,16(3):187-191
The purpose of the present study was to evaluate the responsiveness of normal human airways to beta-adrenoceptor stimulation using a forced oscillation technique. Seven normal volunteers (aged 25 +/- 2 year) were studied on three occasions, separated by weekly intervals, using a single-blind randomized design. On day 1, subjects were given cumulative doses of inhaled salbutamol (100, 200, 500, 1000 micrograms); and identical placebo was given on the other two visits. Respiratory oscillation impedance (Ros) was measured at baseline and 15 min after each dose increment. The coefficients of variation (CV) for short-term intra-individual variability on each placebo day were 7.5 and 9.5, and 9.6% for long-term variability (measured over all three visits). The 95% confidence values (2SD) for the change in Ros required to exclude natural variability were 0.39, 0.50 and 0.53 cmH2O l-1 s, respectively. There was a small fall in Ros in response to salbutamol although the mean maximum change (0.46 cmH2O l-1 s) was not significant (by ANOVA). Thus, the change in Ros (sensitivity) was no greater than the 95% confidence value for natural variability (reproducibility). Regression analysis also showed no evidence of a dose-response relationship for Ros. 相似文献
92.
Chris Clark 《The British journal of general practice》2002,52(480):586-587
93.
94.
Human malignant melanoma may regress spontaneously or with immunotherapy, such as Calmette-Guerin bacillus, interferon alfa, interleukin-2, and interleukin-2 plus lymphokine-activated killer cells. Histamine type 2 receptor antagonists can modulate immune function by inhibiting suppressor T-cell induction and activity, and melanoma regressions have been reported after the use of cimetidine with coumarin or interferon alfa. This article describes the complete regression of melanoma nodules in a patient treated with ranitidine hydrochloride, another histamine type 2-receptor antagonist. Ranitidine and cimetidine should be considered to be possibly active immunotherapeutic agents in the design and evaluation of clinical trials. 相似文献
95.
Jill Macleod Clark PhD BSc RGN Jill Maben MSc BA RGN Karen Jones BA RHV RGN 《Journal of advanced nursing》1997,26(1):161-168
This is the first of two papers which address aspects of the findings of a large scale study commissioned by the English National Board which set out to examine the impact of Project 2000 on perceptions of the philosophy and practice of nursing. The findings presented here suggest that there have been fundamental shifts in perceptions of the nature and discipline of nursing. Students and diplomates of the course perceive themselves as knowledgeable doers, with their practice well grounded in theory and research. They value the interpersonal skills teaching and place the patient firmly at the centre of care delivery, viewing the patient holistically and being prepared to be fierce patient advocates where necessary. It is difficult to determine the extent to which these shifts can be attributed to the Project 2000 course, although the Project 2000 approach to education appears to be an important factor. 相似文献
96.
OBJECTIVE: To test the hypothesis that inhibition of protein kinase (PK) activity or proteolysis inhibits ovulation. DESIGN: Rats were injected intrabursally with protein kinase (H9 or staurosporin) or proteinase (alpha 2-macroglobulin) inhibitors and oocyte release was evaluated. SETTING: Clinical Research Laboratory, Center for Reproductive Medicine, University of Kentucky Medical Center. PARTICIPANTS: Immature rats stimulated with pregnant mare serum gonadotropin. INTERVENTIONS: Staurosporin (1 or 10 microM), H9 (1 mM), alpha 2-macroglobulin (835 microIU of activity); or vehicle was injected into the right ovarian bursa. The left ovarian bursa remained intact. Animals immediately received human chorionic gonadotropin (hCG). MAIN OUTCOME MEASURES: Analysis of oocyte release and ovarian morphology. RESULTS: Oocyte release from the inhibitor-treated side decreased for the H9 group (8.1 +/- 1.9 fewer oocytes released, P less than 0.001) and the 10 microM staurosporin group (5.5 +/- 0.6, P less than 0.001). No change in oocyte release was observed in the 1 microM staurosporin, alpha 2-macroglobulin, or vehicle injected groups. Histologic examination of vehicle treated ovaries demonstrated numerous developing corpora lutea (CL; 20.5 +/- 2.1 CL/ovary) and a lack of preovulatory follicles. In contrast, ovaries treated with PK inhibitors contained unruptured preovulatory follicles coincident with fewer forming CL (11.5 +/- 3.5 CL/ovary). CONCLUSIONS: Inhibition of PK activity in vivo suppresses ovulation, demonstrating that protein phosphorylation plays an important intermediary role in the ovulatory process. 相似文献
97.
Successful cryopreservation of human bone marrow does not require a controlled-rate freezer 总被引:3,自引:0,他引:3
We studied CFU-GM recovery from bone marrow samples frozen either in a machine for controlled-rate freezing or in a -70 degrees C freezer. We found no statistically significant difference between the two methods. Cooling-curve investigations also demonstrated that it was possible to obtain satisfactory cooling rates simply by manipulation of the shape and volume of the marrow and its container. Five patients received a total of six successful autografts for which their marrow cells were frozen without controlled-rate freezing. Thus it is not necessary to use a sophisticated machine in order to obtain satisfactory cryopreservation of human marrow stem cells. 相似文献
98.
BACKGROUND. Cisplatin and 5-fluorouracil have noted synergy in preclinical systems. The authors combined methotrexate with infusional cisplatin and 5-fluorouracil in an attempt to produce a regimen with improved activity in advanced NSCLC. METHODS. Twenty-six ambulatory patients with previously untreated non-small cell lung cancer were treated with continuous-infusion cisplatin (25 mg/m2/day for 5 days), 5-fluorouracil (800 mg/m2/day for 5 days), and intermediate-dose methotrexate (200 mg/m2 on days 15, 22), followed by leucovorin rescue (PFM regimen). RESULTS. Patients received a median of four cycles of therapy. Two patients had a complete response, and 10 had a partial response (overall response rate, 46.2% or 12 of 26). The median time to treatment failure was 22.5 weeks; the median survival was 55 weeks from the start of chemotherapy. There were no toxic deaths attributed to chemotherapy. Thrombocytopenia was the only Grade 4 toxicity (27%). Grade 1/4 and 2/4 peripheral neuropathy occurred in 17 of 26 patients (66%) and was associated with a cumulative cisplatin dose of more than 300 mg/m2. CONCLUSIONS. PFM (using continuous-infusion cisplatin) produced a high response rate but resulted in an high incidence of low-grade peripheral neuropathy. 相似文献
99.
Reperfusion increases neutrophils and leukotriene B4 receptor binding in rat focal ischemia. 总被引:19,自引:0,他引:19
F C Barone D B Schmidt L M Hillegass W J Price R F White G Z Feuerstein R K Clark E V Lee D E Griswold H M Sarau 《Stroke; a journal of cerebral circulation》1992,23(9):1337-47; discussion 1347-8
BACKGROUND AND PURPOSE: Neutrophils are critically involved with ischemia and reperfusion injury in many tissues but have not been studied under conditions of reperfusion after focal cerebral ischemia. The present studies were conducted to confirm our previous observations quantifying neutrophils in rat permanent focal stroke using a myeloperoxidase activity assay and to extend them to transient ischemia with reperfusion. In addition, leukotriene B4 receptor binding in ischemic tissue was evaluated as a potential marker for inflammatory cell infiltration. METHODS: Histological, enzymatic, and receptor binding techniques were used to evaluate neutrophil infiltration and receptor binding in infarcted cortical tissue 24 hours after permanent middle cerebral artery occlusion (n = 25) or temporary occlusion for 80 (n = 12) or 160 (n = 22) minutes followed by reperfusion for 24 hours in spontaneously hypertensive rats. RESULTS: Sham surgery (n = 26) produced no changes in any parameter measured. After permanent middle cerebral artery occlusion, neutrophil accumulation was observed histologically, but the infiltration was moderate and typically within and adjacent to blood vessels bordering the infarcted cortex. After temporary middle cerebral artery occlusion with reperfusion, marked neutrophil infiltration was observed throughout the infarcted cortex. Myeloperoxidase activity was increased (p less than 0.05) after permanent occlusion and to a greater extent after temporary occlusion with reperfusion. Myeloperoxidase activity (units per gram wet weight) in ischemic cortex was increased over that in nonischemic (control) cortex 32.2-fold, 54.6-fold, and 92.1-fold for permanent occlusion and 80 and 160 minutes of temporary occlusion with reperfusion, respectively (p less than 0.05). Sham surgery produced no changes in myeloperoxidase activity. Leukotriene B4 receptor binding also was increased (p less than 0.05) after focal ischemia and paralleled the increases in myeloperoxidase activity. Ischemic cortex-specific receptor binding (femtomoles per milligram protein) was 3.87 +/- 0.63 in sham-operated rats and 4.57 +/- 0.98, 8.98 +/- 1.11, and 11.12 +/- 1.63 for rats subjected to permanent occlusion and 80 and 160 minutes of temporary occlusion with reperfusion, respectively (all p less than 0.05 different from sham-operated). Cortical myeloperoxidase activity was significantly correlated with the degree of cortical leukotriene B4 receptor binding (r = 0.66 and r = 0.79 in two different studies, p less than 0.01). CONCLUSION: These data indicate that neutrophils are involved in focal ischemia and that there is a dramatic accumulation of neutrophils in infarcted tissue during reperfusion that can be quantified using the myeloperoxidase activity assay. Leukotriene B4 receptor binding increases in infarcted tissue in a parallel manner, which suggests that the increased leukotriene B4 binding is to receptors located on the accumulating neutrophils. 相似文献
100.
Mulkerrin EC; Clark BA; Epstein FH 《QJM : monthly journal of the Association of Physicians》1997,90(6):411-415
We studied blood pressure and natriuretic responses to acute salt loading,
and the effect of non-steroidal anti-inflammatory agents on these
responses, in five healthy normotensive women aged 65 to 71 years. Five
women aged 25 to 31 years acted as controls. Intravenous saline loading,
with and without prior ingestion of ibuprofen, was 15 ml/kg/h for 3 h.
Baseline blood pressures were higher in the elderly. Saline infusion
without ibuprofen raised systolic blood pressure (SBP) by about 25 mmHg in
the older group only. Ibuprofen increased baseline SBP in the elderly (129
+/- 6 vs. 116 +/- 5 mmHg, p < 0.05). Saline loading after ibuprofen
again raised blood pressure by about 25 mmHg in the elderly only. The
elderly group showed markedly increased sodium excretion during saline
loading, but this was reduced by ibuprofen. Ibuprofen had no effect on SBP
or sodium excretion in controls. Ageing appears to increase susceptibility
to salt retention and hypertension from non-steroidal anti-inflammatory
agents.
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