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101.
PURPOSE: Fenretinide (4-HPR) is a synthetic retinoid that has shown a preventive activity in prostate cancer animal models. EXPERIMENTAL DESIGN: We measured the changes in total and free prostate-specific antigen (PSA) and its association with insulin-like growth factor I (IGF-I) and IGFBP-3 levels after 1 year of treatment in 24 subjects given 4-HPR and 24 control subjects enrolled in a randomized bladder cancer prevention trial. RESULTS: No significant effect of 4-HPR was observed on total and free fraction of PSA levels. The median percentage [95 confidence interval (95% CI)] change for % free PSA and total PSA in the 4-HPR and the control group were, respectively, 7.6 (95% CI, -4.0 to 69.3) versus 5.1 (95% CI, -21.4 to 59.8) and -7.8 (95% CI, -18.2 to 52.5) versus -12.3 (95% CI, -44.6 to 9.6). However, in patients ages <60 years, there was a trend to an increase of total free PSA and % free PSA after treatment with 4-HPR that was different from a trend to a decrease in the control group (P = 0.002 and 0.052, respectively). The interaction between age and treatment was statistically significant on free PSA (P = 0.001). A similar pattern was noted with smoking status (P = 0.011 for the interaction on free PSA). No association was observed between PSA levels and IGF-I or IGFBP-3 levels. CONCLUSIONS: We conclude that 4-HPR has no significant effect on circulating PSA, but it increases significantly free PSA levels in subjects younger than 60 years and in nonsmokers. These effects might support an activity in prostate cancer prevention but further studies are required.  相似文献   
102.
The distribution of serotonin (5-HT)-containing perikarya, fibers and terminals in the brain of the pigeon (Columba livia) was investigated, using immunohistochemical and immunofluorescence methods combined with retrograde axonal transport. Twenty-one different groups of 5-HT immunoreactive (IR) cells were identified, 2 of which were localized at the hypothalamic level (periventricular organ, infundibular recess) and 19 at the tegmental-mesencephalic and rhombencephalic levels. Ten of the cell groups were situated within the region of the midline from the isthmic to the posterior rhombencephalic level and constituted the raphe system (nucleus annularis, decussatio brachium conjunctivum, area ventralis, external border of the nucleus interpeduncularis, zona peri-nervus oculomotorius, zona perifasciculus longitudinalis medialis, zona inter-flm, nucleus linearis caudalis, nucleus raphe superior pars ventralis, nucleus raphe inferior). The 9 other cell populations belonged to the lateral group and extended from the posterior mesencephalic tegmentum to the caudal rhombencephalon [formatio reticularis mesencephali, nucleus ventrolateralis tegmenti, ectopic area (Ec) of the nucleus isthmo-opticus (NIO), nucleus subceruleus, nucleus ceruleus, nucleus reticularis pontis caudalis, nucleus vestibularis medialis, nucleus reticularis parvocellularis and nucleus reticularis magnocellularis]. Combining the retrograde axonal transport of rhodamine -isothiocyanate (RITC) after intraocular injection and immunohistofluorescence (fluoresceine isothiocyanate: FITC/5-HT) showed the centrifugal neurons (NIO, ec) to be immunonegative. Serotonin-IR fibers and terminals were found to be very broadly distributed within the brain and were particularly prominent in several structures of the telencephalon (archistriatum pars dorsalis, nucleus taeniae, area parahippocampalis, septum), diencephalon (nuclei preopticus medianus, magnocellularis, nucleus geniculatus lateralis pars ventralis, nucleus triangularis, nucleus pretectalis), mesencephalon-rhombencephalon (superficial layers of the optic tectum, nucleus ectomamillaris, nucleus isthmo-opticus and in most of the cranial nerve nuclei). Comparing the present results with those of previous studies in birds suggests some major serotonin containing pathways in the avian brain and clarifies the possible origin of the serotonin innervation of some parts of the brain. Moreover, comparing our results in birds with those obtained in other vertebrate species shows that the organization of the serotoninergic system in many regions of the avian brain is much like that found in reptiles and mammals.Abbreviations Ad Archistriatum pars dorsalis - alp area interpeduncularis - al ansa lenticularis - Ann nucleus annularis - APH area parahippocampalis - Av archistriatum pars ventralis - AVT area ventralis (Tsai) - bcd brachium conjunctivum descendens - BO bulbus olfactorius - ca commisssura anterior - CDL area corticoidea dorsolateralis - Cer cerebellum - cf fiber layer of the olfactory bulb - cg granular cell layer of the olfactory bulb - co chiasma opticum - ct commissura tectalis - dbc decussatio brachiorum conjunctivorum - DL nucleus dorsolateralis anterior thalami - DLP nucleus dorsolateralis posterior thalami - DM nucleus dorsomedialis thalami - dnt decussatio nervi trochlearis - E ectostriatum - Ec ectopic area of the nucleus isthmo-opticus - EM nucleus ectomamillaris - flm fasciculus longitudinalis medialis - fpl fasciculus prosencephali lateralis - FRL formatio reticularis lateralis mesencephali - FRM formatio reticularis medialis mesencephali - fu fasciculus uncinatus - GCt substantia grisea centralis - GLv nucleus geniculatus lateralis pars ventralis - gr granular cell layer of the cerebellum - HA hyperstriatum accessorium - HD hyperstriatum dorsale - HIS hyperstriatum intercalatus superior - HL nucleus habenularis lateralis - HM nucleus habenularis medialis - Hp hippocampus - HV hyperstriatum ventrale - ICo nucleus intercollicularis - i-flm inter fasciculus longitudinalis medialis - Imc nucleus ishmi pars magnocellularis - Ip nucleus interpeduncularis - Ipc nucleus isthmi pars parvocellularis - LA nucleus lateralis anterior thalami - La nucleus laminaris - LC nucleus linearis caudalis - LHy nucleus lateralis hypothalami - lm lemniscus medialis - LoC locus coeruleus - LPO lobus paraolfactorius - ls lemniscus spinalis - MLd nucleus mesencephalicus lateralis pars dorsalis - mo molecular layer of the cerebellum - MoV nucleus motorius nervi trigemini - Mp magnocellularis preopticus - N neostriatum - NIII nucleus nervi oculomotorii - nIII nervus oculomotorius - NIV nucleus nervi trochlearis - NV nucleus nervi trigemini nV nervus trigeminus - NVII nucleus nervifacialis - nVIII nervus octavus - NIO nucleus isthmo-opticus - om tractus occipitomesencephalicus - OPH hypothalamic periventricular organ - Os nucleus olivaris superior - Ov nucleus ovoidalis - PA paleostriatum augmentatum - Po nucleus pontis - POM nucleus preoticus medialis - PP paleostriatum primitivum - PrV nucleus sensorius principalis nervi trigemini - PT nucleus pretectalis - pu Purkinje cell layer - qf tractus quintofrontalis - Rai nucleus raphe inferior - RasV nucleus raphe superior pars ventralis - ReI recessus infundibularis - Rm nucleus reticularis magnocellularis - Rp nucleus reticularis parvocellularis - RPc nucleus reticularis pontis caudalis - RPO nucleus reticularis pontis oralis - Rt nucleus rotundus - Ru nucleus ruber - S septum - Sac stratum album centrale - SCH stratum cellulare hypothalami - Sgc stratum griseum centrale - Sgf stratum griseum et fibrosum superficiale - Sgfp stratum griseum et fibrosum periventriculare - Sop stratum opticum - SP nucleus subpretectalis - SPC nucleus superficialis parvocellularis - Spl nucleus spiriformis lateralis - Spm nucleus spiriformis medialis - SRt nucleus subrotundus - SuC nucleus subcoeruleus - to tractus opticus - Tn nucleus taeniae - TPc nucleus tegmenti pedunculo-pontinus pars compacta - Tr nucleus triangularis - tsm tractus septomesencephalicus - ttd nucleus et tractus descendens nervi trigemini - Tu nucleus tuberis - Vel nucleus vestibularis lateralis - Vem nucleus vestibularis medialis - Vlt nucleus ventrolateralis thalami - VT nucleus ventrolateralis tegmenti - Zp-flm zona perifasciculus longitudinalis medialis - Zp-NIII zona perinervus oculomotorius  相似文献   
103.
Stromal derived factor‐1α (SDF‐1α), the high‐affinity ligand of CXC‐chemokine receptor 4 (CXCR4), was added to human CD34+ hematopoietic progenitor cells that can be induced to differentiate along the monocytic or megakaryocytic lineages. In control liquid cell cultures supplemented with two different cytokine cocktails: stem cell factor (SCF), interleukin‐3 (IL‐3), macrophage‐colony stimulating factor (M‐CSF), and 10% fetal calf serum (FCS), or, SCF and thrombopoietin (TPO), the expression of surface CXCR4 progressively increased in both the CD14+ monocytic and CD41+ megakaryocytic lineages. While SDF‐1α caused only modest effects on cells of the monocytic lineage, it induced profound down‐regulation of CXCR4 in megakaryocytic cells at all stages of differentiation. Moreover, while SDF‐1α initially up‐regulated the early megakaryocytic antigen CD41, at later time points (days 12–16) it induced down‐regulation of the late megakaryocytic antigen CD42b. Consistently, at day 16, the number of mature megakaryocytes was significantly decreased in cultures supplemented with SDF‐1α. These findings indicate that, besides its primary role in regulating the retention of precursor cells in hematopoietic tissues, the SDF‐1α/CXCR4 system participates in the regulation of megakaryocytic development by stimulating the formation of immature megakaryoblasts and inhibiting the formation of mature megakaryocytes. Anat Rec 260:141–147, 2000. © 2000 Wiley‐Liss, Inc.  相似文献   
104.
  1. In the present study the effect of N-methyl-D-aspartate (NMDA) on thromboxane B2 synthesis and on [Ca2+]i was studied in human platelets.
  2. NMDA (10−7M) completely inhibited the synthesis of thromboxane B2 from exogenous arachidonic acid (AA), while it did not interfere with the aggregating effect of the thromboxane A2 receptor agonist U-46619.
  3. NMDA (0.1 μM–10 μM) dose-dependently increased intracellular calcium in washed platelets pre-loaded with fura 2 AM, and this effect was not additive with that of AA.
  4. NMDA shifted the dose-response curve of AA to the right. At the highest AA concentrations platelet aggregation was not inhibited.
  5. The antiaggregating effect of NMDA was not antagonized by NG-monomethyl-L-arginine (L-NMMA), a nitric oxide synthase (NOS) inhibitor.
  6. Finally, NMDA (0.01 nM–100 nM) associated with either aspirin or indomethacin significantly potentiated the antiaggregating activity of both cyclo-oxygenase inhibitors.
  7. It was concluded that NMDA is a potent inhibitor of platelet aggregation and thromboxane B2 synthesis in human platelet rich plasma (PRP).
  相似文献   
105.
The prevalence of eight mutations in 84 patients with β‐thalassaemia major and in 16 subjects with thalassaemia intermedia was investigated. All of the patients were Italian, originating from Eastern Sicily (Messina area) and some Calabrian regions. Genomic DNA was amplified by polymerase chain reaction (PCR). DNA molecular investigations were performed by allele‐specific oligonucleotide (ASO) hybridization, to identify the following β‐thalassaemia mutations: CD39 (C‐T), IVS1‐110 (G‐A), IVS1‐6 (T‐C), IVS1‐1 (G‐A), IVS2‐745 (C‐G), IVS2‐1 (G‐A), ?87 (C‐G), CD6 A (?A). Our data underline that in thalassemia intermedia two mutations were statistically prevalent: IVS1‐6 T→C (P < 0.001) and CD 6‐A (P < 0.05). CD 39 was statistically prevalent in β‐thalassaemia major patients (P < 0.01). The difference between the two groups was not statistically significant for all the other mutations. Five different genotypes were recorded among thalassaemia intermedia and 15 among β‐thalassaemia major patients. Twenty‐five percent of the intermedia patients and 4.5% of the major patients had homozygosity for mild mutations (group I); 62.5% of the intermedia patients and 26.2% of the major patients had combinations of mild/severe mutations (group II). In addition, homozygosity or double heterozygosity for severe mutations (group III) was found in 12.5% of the intermedia patients and 69% of the major patients. Some genotypes were restricted to thalassaemia intermedia, including heterozygosity ?87/IVS1‐6 and IVS1‐6/CD 6‐A. It is essential to understand the distribution and frequency of the relevant mutations in each population where β‐thalassaemias exist. This is of particular importance for genotype–phenotype correlation and for carrier detection, genetic counselling and prenatal diagnosis.  相似文献   
106.
Legionella pneumonia in cancer patients   总被引:1,自引:0,他引:1  
Legionella is an important cause of nosocomial and community-acquired pneumonia in both immunocompetent and immunosuppressed patients worldwide; however, the clinical course and optimal antibiotic therapy of Legionella pneumonia (LP) in patients with cancer is uncertain. We studied retrospectively the risk factors, clinical manifestations, and outcome of 49 cancer patients with a positive Legionella culture or direct fluorescent antibody (DFA) over a 13-year period (1991-2003). The majority of patients (82%) had an underlying hematologic malignancy, and 37% were bone marrow transplant recipients; 80% of the patients had active malignancy. Lymphopenia (47%), use of systemic corticosteroids (41%), and chemotherapy (63%) were the most common underlying conditions. The laboratory diagnosis was established by positive Legionella culture (n = 8, 16%), DFA (n = 29, 59%), or both (n = 12, 25%). In 4 patients (8%), a positive DFA was deemed to represent false-positive results. There was no temporal or geographic clustering of cases. The majority of the cases had multilobar (61%) or bilateral (55%) pulmonary involvement.The mean time to response to therapy was 8 days; 18 patients (37%) developed complications requiring prolonged duration of treatment (mean, 25 d). The case-fatality rate was 31%. Two patients had relapse of LP despite appropriate therapy. Improved outcome, especially in those with severe pneumonia, seemed to correlate with the use of a combination of antibiotics. LP is an uncommon infection in our patient population but is associated with significant morbidity and mortality. Treatment of LP in cancer patients may require a prolonged course with a regimen that includes a newer macrolide or quinolone.  相似文献   
107.
IntroductionDysfunctional breathing (DB) can be defined by the presence of unexplained breathing symptoms. However, validated questionnaires to comprehensively evaluate all dimensions of breathing symptoms proposed to be associated with DB have not been extensively developed. This paper discusses the development and exploration of the dimensionality of a preliminary questionnaire, the Self Evaluation of Breathing Questionnaire, whose items were derived from a popular Internet questionnaire for evaluating breathing functionality and breathing symptoms proposed in the scientific literature to be discriminative for DB.MethodThe 17-item SEBQ was administered to 83 adults. Exploratory factor analysis was performed and correlations calculated between the SEBQ and the Nijmegen Questionnaire (NQ), which is a validated questionnaire for hyperventilation syndrome.Results/DiscussionTwo dimensions were found in the SEBQ. One dimension named “lack of air” appears to reflect sensations of air hunger that may relate more to chemoreceptor aspects of breathing sensation. The other dimension named “perception of inappropriate or restricted breathing” appears to reflect sensations and observations about the work of breathing and may relate more to the biomechanical aspects of breathing sensation. The correlations between the SEBQ and the NQ were .6 for the 17-item SEBQ and .3 for the final 12-item SEBQ which contained the strongest items of the two dimensions.ConclusionBreathing symptoms associated with dysfunctional breathing arising from predominately biomechanical aspects of breathing might be distinguishable from symptoms arising from factors reflecting chemoreceptor input. The two dimensions of the SEBQ may represent related but distinct aspects of dysfunctional breathing symptoms that appear different to those assessed by the Nijmegen Questionnaire. The SEBQ, if further developed, may be a useful clinical assessment tool that could more discriminatively evaluate the response of separate dimensions of breathing symptoms to treatments that aim to improve the functionality of breathing.  相似文献   
108.
End stage renal disease among ceramic workers exposed to silica   总被引:2,自引:1,他引:1  
OBJECTIVES: To evaluate whether ceramic workers exposed to silica experience an excess of end stage renal disease. METHODS: On the basis of a health surveillance programme, a cohort of 2980 male ceramic workers has been enrolled during the period 1974-91 in Civitacastellana, Lazio, Italy. For each worker, employment history, smoking data, and x ray film readings were available. The vital status was ascertained for all cohort members. All 2820 people still alive and resident in the Lazio region as in June 1994 were searched for a match in the regional end stage renal diseases registry, which records (since June, 1994) all patients undergoing dialysis treatment in public and private facilities of the region. Expected numbers of prevalent cases from the cohort were computed by applying the rate of patients on dialysis treatment by the age distribution of the cohort. RESULTS: A total of six cases was detected when 1.87 were expected (observed/expected (O/E) = 3.21; 95% confidence interval (95% CI) 1.17 to 6.98). The excess risk was present among non-smokers (O = 2; O/E = 4.34) and smokers (O = 4; O/E = 2.83), as well as among workers without silicosis (O = 4; O/E = 2.78) and workers with silicosis (O = 2; O/E = 4.54). The risk was higher among subjects with < 20 years since first employment (O = 4; O/E = 4.65) than among those employed > 20 years. CONCLUSION: These results provide further evidence that exposure to silica dust among ceramic workers is associated with nephrotoxic effects.

 

  相似文献   
109.
Nicotine improves cognitive performance and attention in both experimental animals and in human subjects, including patients affected by neuropsychiatric disorders. However, the specific molecular mechanisms underlying nicotine-induced behavioral changes remain unclear. We have recently shown in mice that repeated injections of nicotine, which achieve plasma concentrations comparable to those reported in high cigarette smokers, result in an epigenetically induced increase of glutamic acid decarboxylase 67 (GAD67) expression. Here we explored the impact of synthetic α4β2 and α7 nAChR agonists on GABAergic epigenetic parameters. Varenicline (VAR), a high-affinity partial agonist at α4β2 and a lower affinity full agonist at α7 neuronal nAChR, injected in doses of 1–5 mg/kg/s.c. twice daily for 5 days, elicited a 30–40% decrease of cortical DNA methyltransferase (DNMT)1 mRNA and an increased expression of GAD67 mRNA and protein. This upregulation of GAD67 was abolished by the nAChR antagonist mecamylamine. Furthermore, the level of MeCP2 binding to GAD67 promoters was significantly reduced following VAR administration. This effect was abolished when VAR was administered with mecamylamine. Similar effects on cortical DNMT1 and GAD67 expression were obtained after administration of A–85380, an agonist that binds to α4β2 but has negligible affinity for α3β4 or α7 subtypes containing nAChR. In contrast, PNU–282987, an agonist of the homomeric α7 nAChR, failed to decrease cortical DNMT1 mRNA or to induce GAD67 expression. The present study suggests that the α4β2 nAChR agonists may be better suited to control the epigenetic alterations of GABAergic neurons in schizophrenia than the α7 nAChR agonists.  相似文献   
110.
Stimulation of tumor growth in adult rats in vivo during an acute fast   总被引:2,自引:0,他引:2  
These experiments investigate an increase in tumor growth that occurs in adult rats in vivo during an acute fast. The effects of feeding, fasting, and underfeeding on the growth of Morris hepatomas 5123C and 7288CTC in Buffalo rats and of Walker carcinoma 256 and Jensen sarcoma in Sprague-Dawley rats were studied. Animals were matched for tumor size and growth during a period of ad libitum feeding preceding the fasting or underfeeding. Tumor growth was documented by increased size and incorporation of [methyl-3H]thymidine into tumor DNA. Fasting increased the rate of growth of the tumors 3 to 4 times over that measured in fed rats. This effect began during the first day of fasting and ended abruptly on refeeding. After refeeding tumor growth slowed to the rate in fed rats. Tumors from fed or fasted rats were not different in cellularity or dry weight/g wet weight. A positive growth response in the tumor required lipolysis and ketosis in the host. No stimulation was observed during an acute fast in either immature rats or in mature rats whose weights had been reduced by underfeeding. These animals have small fat stores and show no increase in arterial blood free fatty acid or ketone body concentrations during an acute fast. Finally, underfeeding of adult rats raised the blood concentrations of these nutrients to values that were intermediate between those in fasted and fed rats. Tumor growth rates in these rats were intermediate between those in fasted and fed rats. The results support the proposal that an increase in availability of free fatty acids and/or ketone bodies is the stimulus that increases the rate of tumor growth during an acute fast.  相似文献   
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