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David J. Seiffge MD Gian Marco De Marchis MD Masatoshi Koga MD PhD Maurizio Paciaroni MD Duncan Wilson PhD Manuel Cappellari MD Kosmas Macha MD Georgios Tsivgoulis MD Gareth Ambler PhD Shoji Arihiro MD Leo H. Bonati MD Bruno Bonetti MD Bernd Kallmünzer MD Keith W. Muir MD PhD Paolo Bovi MD Henrik Gensicke MD Manabu Inoue MD Stefan Schwab MD Shadi Yaghi MD Martin M. Brown MD PhD FRCP Philippe Lyrer MD Masahito Takagi MD PhD Monica Acciarrese MD Hans Rolf Jager MD FRCP Alexandros A. Polymeris MD Kazunori Toyoda MD PhD Michele Venti MD Christopher Traenka MD Hiroshi Yamagami MD PhD Andrea Alberti MD Sohei Yoshimura MD PhD Valeria Caso MD Stefan T. Engelter MD David J. Werring MD PhD FRCP the RAF RAF-DOAC CROMIS- SAMURAI NOACISP Erlangen and Verona registry collaborators 《Annals of neurology》2020,87(5):677-687
83.
We have examined the effects of total body iron deficiency on the function of mitochondria isolated from rat hearts. Male Wistar rats were weaned at 21 days and divided into an experimental iron-deficient group and a control group. Both groups received identical diet but an iron supplement (180 mg of ferrous sulfate per kg of diet) was added for the control group. Rats were studied at 7 and 14 weeks. Iron-deficient rats weighed less than controls but showed significantly increased ventricle to body weight ratio at both 7 and 14 weeks, indicating relative cardiac hypertrophy. Isolated mitochondrial fractions from iron-deficient and control rats contained similar proportions of whole homogenate protein and succinic cytochrome c reductase activity, indicating that the fractions isolated from the experimental and control rats were comparable. In iron-deficient rats NADH cytochrome c reductase, succinic cytochrome c reductase, succinic dehydrogenase, and NADH ferricyanide oxidoreductase activities were all significantly reduced at 7 and 14 weeks. Cytochrome c oxidase activity was significantly reduced only at 14 weeks as were the concentrations of cytochromes a3, c1, and b. The rate of oxygen uptake by mitochondria was significantly lower at both 7 and 14 weeks but the P/O ratio was unaltered. We conclude that iron deficiency is associated with impairment of myocardial mitochondrial electron transport. 相似文献
84.
Susanne Coleman BSc RGN E. Andrea Nelson PhD RGN Justin Keen MSc PhD Lyn Wilson MA RGN Elizabeth McGinnis MSc PhD RGN Carol Dealey PhD RGN Nikki Stubbs MSc RGN Delia Muir BA Amanda Farrin MSc Dawn Dowding PhD RN Jos M.G.A. Schols MD PhD Janet Cuddigan PhD RN FAAN Dan Berlowitz MD MPH Edward Jude MD MRCP Peter Vowden MD FRCS Dan L. Bader PhD DSc Amit Gefen PhD Cees W.J. Oomens PhD Lisette Schoonhoven PhD RN Jane Nixon PhD RN 《Journal of advanced nursing》2014,70(10):2339-2352
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Strips of smooth muscle from the cervical tracheae of six adult male crab-eating monkeys (Macaca fascicularis) were studied in jacketed 25 ml organ baths filled with Krebs-bicarbonate solution maintained at 37 degrees C and gassed with 5% CO2 in oxygen. Isometric tissue tension increased in response to electrical field stimulation (18 V, 25 Hz, 0.5 msec), norepinephrine in the presence of propranolol, acetylcholine and histamine. Atropine abolished the contractile response to electrical stimulation. Tissues that were contracted with acetylcholine or pretreated with atropine then contracted with histamine relaxed when stimulated electrically. The relaxation was unaffected by propranolol but was abolished by tetrodotoxin. Isoproterenol relaxed tissues that were contracted with histamine, but failed to relax histamine-contracted tissues that had been pretreated with propranolol. Norepinephrine did not change isometric tension in untreated tissues or tissues pretreated with phentolamine. These results demonstrate the presence of excitatory and inhibitory nerves and noninnervated beta-adrenergic receptors in macaque trachealis. The excitatory nerves appear to be cholinergic. The inhibitory response to electrical stimulation is not mediated through muscarinic cholinergic or beta-adrenergic receptors. The inhibitory response to electrical field stimulation was likely mediated through nonadrenergic noncholinergic nerves. 相似文献
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Muir P Ras A Klapper PE Cleator GM Korn K Aepinus C Fomsgaard A Palmer P Samuelsson A Tenorio A Weissbrich B van Loon AM 《Journal of clinical microbiology》1999,37(5):1409-1414
We conducted a multicenter evaluation of commercial and in-house PCR methods for the detection of enteroviruses. Three coded panels of test and control RNA samples, artificial clinical specimens, and representative enterovirus serotypes were used to assess amplification methods, RNA extraction methods, and reactivities with different enterovirus serotypes. Despite several differences between PCR methods, there was good agreement, although some variation in sensitivity was observed. Most PCR methods were able to detect enterovirus RNA derived from 0.01 50% tissue culture infective dose (TCID50) and were able to detect at least 1 TCID50 of enterovirus in cerebrospinal fluid, stool, or throat swab specimens. Most were also able to detect a wide range of enterovirus serotypes, although serotypic identification was not possible. Some laboratories experienced false-positive results due to PCR contamination, which appeared to result mainly from cross-contamination of specimens during RNA extraction. Provided that this problem is overcome, these PCR methods will prove to be a sensitive and rapid alternative to cell culture for the diagnosis of enterovirus infection. 相似文献
90.
C-reactive protein and outcome after ischemic stroke 总被引:107,自引:0,他引:107
Muir KW Weir CJ Alwan W Squire IB Lees KR 《Stroke; a journal of cerebral circulation》1999,30(5):981-985
BACKGROUND AND PURPOSE: Elevated concentrations of the acute-phase reactant C-reactive protein (CRP) predict ischemic cardiac events in both hospital- and population-based studies and may signify a role for inflammation in the destabilization of cardiovascular disease. We examined the relationship between CRP and outcome after acute ischemic stroke. METHODS: This was a subgroup analysis from a prospective observational study based in a University Hospital Acute Stroke Unit serving a population of approximately 260 000. Survival time and cause of death for up to 4 years after the index stroke were determined and related to CRP concentration within 72 hours of stroke and known prognostic variables by a Cox proportional hazards regression model. RESULTS: Ischemic stroke was diagnosed in 228 of 283 consecutive admissions. Median follow-up was 959 days. Geometric mean CRP concentration was 10.1 mg/L. Survival in those with CRP >10.1 mg/L was significantly worse than in those with CRP =10.1 mg/L (P=0.00009, log-rank test). Higher CRP concentration was an independent predictor of mortality (hazard ratio, 1.23 per additional natural log unit; 95% CI, 1.13 to 1.35; P=0.02), together with age and stroke severity on the National Institutes of Health Stroke Scale. Cardiovascular disease accounted for 76% of deaths in those with CRP >10.1 mg/L and 63% of deaths in those with CRP =10. 1 mg/L. CONCLUSIONS: CRP concentration is an independent predictor of survival after ischemic stroke. These findings are consistent with a role for inflammation in acute ischemic stroke, as well as with the hypothesis that elevated CRP may predict future cardiovascular mortality. 相似文献