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71.
Anju Huria Khosla MD Krishna Sangwan MD Shanti Devi Ahuja MBBS 《The Australian & New Zealand journal of obstetrics & gynaecology》1997,37(3):294-296
EDITORIAL COMMENT: This study of amnioinfusion during labour complicated by the known passage of meconium shows that the technique seems clinically worthwhile, even in a centre without facilities for electronic fetal heart monitoring or scalp blood pH and blood gas analysis. The series is small and more data from larger studies is required to test the conclusions reported by the authors.
Summary: A prospective study to see the safety and efficacy of transcervical amnioinfusion in labour complicated by meconium-stained amniotic fluid (MSAF) was carried out in a teaching hospital with limited resources. Fifty patients in labour with meconium-stained amniotic fluid and fulfilling the inclusion criteria (vertex presentation, gestational age of 36 weeks or more, no medical or obstetrical complications and normal fetal heart rate at time of inclusion) were taken for the study; 25 patients received amnioinfusion. The control group received only supportive therapy. Labour outcome was compared in the 2 groups. The incidence of Caesarean section was seen to be decreased but neonatal parameters showed no significant difference in the amnioinfusion group. 相似文献
Summary: A prospective study to see the safety and efficacy of transcervical amnioinfusion in labour complicated by meconium-stained amniotic fluid (MSAF) was carried out in a teaching hospital with limited resources. Fifty patients in labour with meconium-stained amniotic fluid and fulfilling the inclusion criteria (vertex presentation, gestational age of 36 weeks or more, no medical or obstetrical complications and normal fetal heart rate at time of inclusion) were taken for the study; 25 patients received amnioinfusion. The control group received only supportive therapy. Labour outcome was compared in the 2 groups. The incidence of Caesarean section was seen to be decreased but neonatal parameters showed no significant difference in the amnioinfusion group. 相似文献
72.
T. M. Ramanujam A. Sergius V. Usha S. Ramanathan 《Pediatric surgery international》1998,14(1-2):134-137
Urethral duplication (UD) is an uncommon malformation. Obstruction rarely occurs in hypospadiac UD. We describe two children
with incomplete hypospadiac UD in association with posterior urethral valves, a combination not previously recognised. The
embryonic significance of this anomaly is discussed.
Accepted: 30 September 1997 相似文献
73.
OBJECTIVE: To evaluate the absolute CD4 cell counts of all the newly diagnosed HIV-infected persons who presented at the Ladymeade Reference Unit (LRU), which serves as the national HIV/AIDS referral and treatment center for the country of Barbados. DESIGN AND METHODS: The study group was comprised of HIV-infected adults who had been diagnosed with HIV infection and referred to the LRU between January and December 2002. All the patients referred to the LRU had a CD4 cell count done at their first visit to the unit, as part of the routine workup to assess their disease status and need for antiretroviral therapy. RESULTS: Of the 106 newly diagnosed adults, 62 of them (58.5%) were males, who had a median age at presentation of 40 years; the other 44 of them (41.5%) were females, and their median age at presentation was 36 years. Nearly one-fifth (18.2%) of the females were aged 16-25 years, whereas only 8.1% of the males were in this age group. The majority (57.6%) of the study group were diagnosed because they presented with an HIV/AIDS-related illness. Overall, the median CD4 cell count at the time of diagnosis was 183/microL; 52 of 103 adults (50.5%) with a newly diagnosed HIV infection had a CD4 cell count that was < 200. Among males, the median CD4 cell count was 161/microL, and 32 (53.3%) of 60 males had CD4 cell counts < 200. In contrast, among females, the median CD4 cell count was 223, and 20 (46.5%) of 43 females had a CD4 cell count that was < 200/microL. However, this difference in the proportion of males and females with a CD4 cell count less than 200/microL was not statistically significant (P = 0.63). CONCLUSIONS: At the time of HIV diagnosis, over one-half of the adults had an initial CD4 cell count that was consistent with relatively advanced disease. Proportionally more women than men presented at a younger age, and proportionally more women than men presented in the early stages of the disease. These patterns indicate a clear need for enhanced educational efforts regarding the importance of HIV testing for at-risk individuals across Barbados. This testing could improve efforts to reduce transmission as well as the prognosis for patients who receive antiretroviral therapy. 相似文献
74.
I. E. Ezeagu A. G. Gopal Krishna S. Khatoon L. R. Gowda 《Ecology of food and nutrition》2004,43(4):295-305
Analysis showed the seeds of Adenanthera pavonina contained appreciable amounts of proteins (29.44g/100g), crude fat (17.99g/100g), and minerals, comparable to commonly consumed staples. Total sugar was low (8.2g/100g) while starch (41.95g/100g) constitutes the major carbohydrates. Low levels of antinutrients were reported and methionine and cystine were the most deficient amino acids. Linoleic and oleic acids make up 70.7 percent of the total fatty acids. Free fatty acid levels were relatively high but peroxide and saponification values of 29.6mEqkg-1 and 164.1mgKOHg-1respectively point to a resemblance to oils processed for food. It was concluded that A. pavonina seeds represent a potential source of oil and protein that could alleviate shortages. 相似文献
75.
Monica S Vavilala Lorri A Lee Krishna Boddu Elizabeth Visco David W Newell Jerry J Zimmerman Arthur M Lam 《Pediatric critical care medicine》2004,5(3):257-263
OBJECTIVE: The aims of this study were to document the incidence of impaired cerebral autoregulation in children with traumatic brain injury using transcranial Doppler ultrasonography and to examine the relationship between autoregulatory capacity and outcome in children following traumatic brain injury. DESIGN: Prospective cohort study. SETTING: Harborview Medical Center (level I pediatric trauma center) in Washington state. PATIENTS: Thirty-six children <15 yrs old with traumatic brain injury: Glasgow Coma Scale score <9 (n = 12, group 1), Glasgow Coma Scale score 9-12 (n = 12, group 2), and Glasgow Coma Scale score 13-15 (n = 12, group 3). INTERVENTIONS: Cerebral autoregulation testing was conducted during extracranial surgery. Mean middle cerebral artery flow velocities were measured using transcranial Doppler as mean arterial pressure was increased to whichever variable was greater: 20% above baseline or a set value (80 mm Hg for <9 yrs and 90 mm Hg for 9-14 yrs). Autoregulatory capacity was quantified by the Autoregulatory Index. Autoregulatory Index <0.4 was considered impaired cerebral autoregulation. Discharge outcome using the Glasgow Outcome Scale score was considered good if the Glasgow Outcome Scale score was > or =4. MEASUREMENTS AND MAIN RESULTS: Twenty-four (67%) of 36 children had an Autoregulatory Index > or =0.4. The incidence of impaired cerebral autoregulation was 42% (five of 12) in group 1, 42% (five of 12) in group 2, and 17% (two of 12) in group 3. Ten (42%) of the 24 children with intact cerebral autoregulation had a good outcome compared with only one of 12 (8%) children with impaired cerebral autoregulation (p =.04). Six of 12 (50%) children with impaired cerebral autoregulation had hyperemia compared with one of 24 (4%) children with intact cerebral autoregulation (p <.01). Hyperemia was associated with poor outcome (p =.01). CONCLUSIONS: The incidence of impaired cerebral autoregulation was greatest following moderate to severe traumatic brain injury. Impaired cerebral autoregulation was associated with poor outcome. Hyperemia was associated with impaired cerebral autoregulation and poor outcome. 相似文献
76.
Synaptic terminals are sites of high metabolic activity and thus are particularly vulnerable to oxidative stress. Oxidative damage to proteins can be toxic to neurons and may cause irreversible cell damage and neurodegeneration. A neuroprotective mechanism used by cells to combat oxidative damage is to selectively degrade damaged proteins. Therefore, it is of interest to study the mechanism of degradation of oxidatively damaged proteins in synaptosomes. One way of oxidizing synaptosomal proteins in vitro is by incubating intact synaptosomes in the presence of an oxidizing agent. A problem with this approach is that it may also cause oxidative damage to the machinery required to recognize and degrade oxidized proteins. We have, therefore, introduced a fluorescent macromolecule into synaptosomes to assess the feasibility of using this technique to study how oxidized proteins are degraded and removed from synaptic terminals. Synaptosomes were subjected to electroporation in the presence of FITC labelled-dextran with an average molecular weight of 70000 (FD-70) and non-specific binding was determined by running parallel experiments in lysed synaptosomes. Following extensive washing, synaptosomes were assayed for the presence of intra-synaptosomal FD-70 by measuring fluorescence in a microplate fluorescence reader. Significant differences in fluorescence were found between intact and lysed synaptosomes with maximal uptake at 100 V/ 1500 microF (approx. 36 pmol/mg protein). To determine if membrane transport was compromised by electroporation, uptake of 3H-arginine was compared in control and electroporated synaptosomes. While untreated electroporated synaptosomes showed a loss of 22% in the ability to transport arginine, preincubation in the presence of 1 mM ATP resulted in a complete restoration of arginine transport. These results show that electroporation is a potentially useful technique for introducing a specific oxidized protein, into synaptic terminals so its metabolic fate can be examined. 相似文献
77.
Brain undergoes neurodegeneration when excess free radicals overwhelm antioxidative defense systems during senescence, head trauma and/or neurotoxic insults. A site-specific accumulation of ferrous citrate-iron complexes in the substantia nigra dopaminergic neurons could lead to exaggerated dopamine turnover, dopamine auto-oxidation, free radical generation, and oxidant stress. Eventually, this iron-catalyzed dopamine auto-oxidation results in the accumulation of neuromelanin, a progressive loss of nigral neurons, and the development of Parkinson's disease when brain dopamine depletion is greater than 80%. Emerging evidence indicates that free radicals such as hydroxyl radicals ((.-)OH) and nitric oxide ((.-)NO) may play opposite role in cell and animal models of parkinsonism. (.-)OH is a cytotoxic oxidant whereas oNO is an atypical neuroprotective antioxidant. (.-)NO and S-nitrosoglutathione (GSNO) protect nigral neurons against oxidative stress caused by 1-methyl-4-phenylpyridinium (MPP(+)), dopamine, ferrous citrate, hemoglobin, sodium nitroprusside and peroxynitrite. MPP(+), the toxic metabolite of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), increases the nigral uptake of iron complexes and dopamine overflow leading to the generation of (.-)OH, protein oxidation, lipid peroxidation, and associated retrograde degeneration. In addition to GSNO, MPP(+)-induced oxidative neurotoxicity can be prevented by antioxidants including selegiline, 7-nitroindazole, 17beta-estradiol, melatonin, alpha-phenyl-tert-butylnitrone and U78517F. Similar to selegiline, 7-nitroindazole is a MAO-B inhibitor, which blocks the bio-activation of MPTP and oxidative stress. Freshly prepared but not light exposed, (.-)NO-exhausted GSNO is about 100 times more potent than the classic antioxidant glutathione. Via S-nitrosylation, GSNO also inhibits proteolysis and cytotoxicity caused by caspases and HIV-1 protease. Furthermore, in addition to protection against serum deprivation stress, the induction of neuronal NOS1 in human cells increases tolerance to MPP(+)-induced neuro-toxicity since newly synthesized (.-)NO prevents apoptosis possibly through up-regulation of bcl-2 and down regulation of p66(shc). In conclusion, reactive oxygen species are unavoidable by-products of iron-catalyzed dopamine auto-oxidation, which can initiate lipid peroxidation, protein oxidation, DNA damage, and nigral loss, all of which can be prevented by endogenous and exogenous (.-)NO. Natural and man-made antioxidants can be employed as part of preventative or neuroprotective treatments in Parkinson's disease and perhaps dementia complexes as well. For achieving neuroprotection and neuro-rescue in early clinical parkinsonian stages, a cocktail therapy of multiple neuroprotective agents may be more effective than the current treatment with extremely high doses of a single antioxidative agent. 相似文献
78.
Toxicity and mAChRs binding activity of Cassiopea xamachana venom from Puerto Rican coasts. 总被引:1,自引:0,他引:1
A separation of toxic components from the upside down jellyfish Cassiopea xamachana (Cx) was carried out to study their cytotoxic effects and examine whether these effects are combined with a binding activity to cell membrane receptors. Nematocysts containing toxins were isolated from the autolysed tentacles, ruptured by sonication, and the crude venom (CxTX) was separated from the pellets by ultracentrifugation. For identifying its bioactive components, CxTX was fractionated by gel filtration chromatography into six fractions (named fraction I-VI). The toxicity of CxTX and fractions was tested on mice; however, the hemolytic activity was tested on saline washed human erythrocytes. The LD50 of CxTX was 0.75 microg/g of mouse body and for fraction III, IV and VI were 0.28, 0.25 and 0.12 microg/g, respectively. Fractions I, II and V were not lethal at doses equivalent to LD50 1 microg/g. The hemolytic and phospholipase A2 (PLA2) activities of most fractions were well correlated with their mice toxicity. However, fraction VI, which contains the low molecular mass protein components (< or =10 kDa), has shown no PLA2 activity but highest toxicity to mice, highest hemolytic activity, and bound significantly to the acetylcholine muscarinic receptors (mAChRs) isolated from rat brain. The results suggested that fraction VI contains proteinaceous components contributing to most of cytolysis as well as membrane binding events. Meanwhile, fraction IV has shown high PLA2 that may contribute to the venom lethality and paralytic effects. 相似文献
79.
Mace L Rothenberg Bonnie LaFleur Donna E Levy Mary Kay Washington Sherry L Morgan-Meadows Ramesh K Ramanathan Jordan D Berlin Al B Benson Robert J Coffey 《Journal of clinical oncology》2005,23(36):9265-9274
PURPOSE: The clinical objective of this trial was to evaluate gefitinib in patients with metastatic colorectal cancer that had progressed despite prior treatment. Serial tumor biopsies were performed when possible and analyzed for activation of the epidermal growth factor receptor (EGFR) signaling pathway. Serial serum samples were measured for amphiregulin and transforming growth factor-alpha (TGFalpha). PATIENTS AND METHODS: One hundred fifteen patients were randomly assigned to receive gefitinib 250 or 500 mg orally once a day. One hundred ten patients were assessable for clinical efficacy. Biologic evaluation was performed on paired tumor samples from 28 patients and correlated with clinical outcome. RESULTS: Median progression-free survival was 1.9 months (95% CI, 1.8 to 2.1 months) and 4-month progression-free survival rate was 13% +/- 5%. One patient achieved a radiographic partial response (RR = 1%; 95% CI, 0.01% to 5%). Median survival was 6.3 months (95% CI, 5.1 to 8.2 months). The most common adverse events were skin rash, diarrhea, and fatigue. In the biopsy cohort, expression of total or activated EGFR, activated Akt, activated MAP-kinase, or Ki67 did not decrease following 1 week of gefitinib. However, a trend toward decreased post-treatment levels of activated Akt and Ki67 was observed in patients with a PFS higher than the median, although these did not reach the .05 level of significance. CONCLUSION: Gefitinib is inactive as a single agent in patients with previously treated colorectal cancer. In tumor samples, gefitinib did not inhibit activation of its proximal target, EGFR. Trends were observed for inhibition of downstream regulators of cellular survival and proliferation in patients achieving longer progression-free survival. 相似文献
80.
Malaya Gupta Upal Kanti Mazumder Ramanathan Sambath Kumar Thangavel Siva Kumar 《Acta pharmacologica Sinica》2004,25(8):1070-1076
AIM: To study the antitumor effect and antioxidant role of Bauhinia racemosa. METHODS: Antitumor activity and antioxidant status of methanol extract (50, 100, and 200 mg/kg) of Bauhinia racemosa stem bark was evaluated against Ehrlich ascites carcinoma (EAC) tumor in mice. Acute and short-term toxicity studies were performed initially in order to ascertain the safety of methanol extract of Bauhinia racemosa (MEBR). After 24 h of tumor inoculation, the extract was administered daily for 14 d. After administration of the last dose followed by 18 h fasting, mice were then sacrificed for observation of antitumor activity. The effect of MEBR on the growth of transplantable murine tumor, life span of EAC bearing hosts and simultaneous alterations in the hematological profile and liver biochemical parameters (lipid peroxidation, antioxidant enzymes) were estimated. RESULTS: The MEBR showed decrease in tumor volume, packed cell volume and viable cell count, and increased the nonviable cell count and mean survival time thereby increasing life span of EAC tumor bearing mice. Hematological profile reverted to more or less normal levels in extract treated mice. Treatment with MEBR decreased the levels of lipid peroxidation and increased the levels of glutathione, superoxide dismutase and catalase. CONCLUSION: The methanol extract of Bauhinia racemosa stem bark exhibited antitumor effect by modulating lipid peroxidation and augmenting antioxidant defense system in EAC bearing mice. 相似文献