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991.
D Martínez-Ares I Martín-Granizo Barrenechea J Souto-Ruzo J Yá?ez López A Pallarés Peral J L Vázquez-Iglesias 《Revista española de enfermedades digestivas》2005,97(12):877-886
INTRODUCTION: Colon cancer is one of the main causes of cancer death. Diagnosis requires the examination of the entire large bowel by means of radiological or endoscopic techniques. Many patients suspect of colon cancer are referred for colonoscopy but nevertheless this suspicion is not confirmed after endoscopic examination. The objective of this study is the evaluation of the reliability of abdominal ultrasound in the diagnosis of these tumors. MATERIAL AND METHOD: We selected patients suspect of colon cancer referred to the endoscopy unit for a colonoscopy. An abdominal ultrasound was carried out on all patients prior to the endoscopy. Considering the endoscopic examination as a gold standard, the sensibility, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the ultrasonography were evaluated. Likewise, a series of analytical and clinical parameters were evaluated, in an attempt to establish associated factors of a colon cancer. The statistical analysis was carried out by means of the statistical package SPSS 12.0 for Windows. RESULTS: 145 patients were included in the study (56.6% males) with an average 66.72 years of age (22-89). A cancer was diagnosed in 42 cases (28.9%). In the diagnosis of colon cancer, abdominal ultrasound presents a sensitivity of 79.06%, a specificity of 92.15%, a PPV and a NPV of 80.9% and of 91.2%, respectively. Excluding from the analysis lesions of the rectal ampulla, which cannot be adequately evaluated by means of ultrasound, the figures for sensitivity, specificity, PPV and NPV increase to 91.8, 92.1, 80.9 and 96.9% respectively. The univariate analysis showed that an age over 65 years and the presence of microcytosis are associated to a greater risk of colon cancer while after multivariate analysis only the presence of microcytosis resulted to be an independent predictive factor of cancer. CONCLUSIONS: Abdominal ultrasound presents high sensitivity, specificity, PPV and NPV in the diagnosis of colon cancer. The combination of an ultrasonography and a rectoscopy permits us to rule out the presence of a colorectal carcinoma. In patients with microcytosis of 65 years and over, if there is strong clinical suspicion, a negative ultrasound may not be sufficient to rule out a colorectal neoplasia. 相似文献
992.
Leonardo F Fontenelle Edward C Lauterbach Leonardo L Telles Marcio Versiani Fábio H Porto Mauro V Mendlowicz 《Cognitive and behavioral neurology》2007,20(1):21-24
OBJECTIVE: We describe the case of a patient who developed an episode of catatonia during the course of her life-long obsessive-compulsive disorder (OCD) and discuss issues related to the etiopathogenesis, differential diagnosis, and therapeutic management of this association. BACKGROUND: Catatonia is conventionally considered a heterogeneous syndrome of motor dysregulation characterized by mutism, immobility, negativism, posturing (catalepsy), stereotypies, and echophenomena. The relationship between OCD and catatonia is still misunderstood and poses significant challenges to the diagnosis and treatment of patients with both conditions. METHOD: Naturalistic follow-up of a single case. RESULTS: A patient with OCD developed catatonia in concert with deteriorating mood, thought, and behavior. This atypical clinical presentation of individuals with OCD and the list of differential diagnosis raised during the patient's clinical assessment are discussed on 3 different levels: symptomatic presentation, comorbidity pattern, and pharmacodynamic mechanisms involved. CONCLUSIONS: The development of a systematic therapeutic plan for patients with OCD and comorbid catatonia includes: the fine-tuning of the antiobsessional treatment; management of comorbid disorders that may engender catatonia; prompt discontinuation, and subsequent slow reintroduction of drugs deemed to trigger toxic reactions or to worsen comorbid disorders and, ultimately, the catatonia; and the implementation of specific anticatatonia measures. 相似文献
993.
994.
Scheila R Schaffazick Adriana R Pohlmann Teresa Dalla-Costa Sílvia S Guterres 《European journal of pharmaceutics and biopharmaceutics》2003,56(3):501-505
Different polymeric nanoparticles were freeze-dried and the powders compared to determine the influence of the lipophilic core (Miglyol 810) or benzyl benzoate) and polymeric material (poly(epsilon-caprolactone) or Eudragit S90) on their drug content and morphology. Diclofenac, a non-steroidal anti-inflammatory drug, was used as a model. To characterize the products, a biological experiment based on the evaluation of the mucosal toxicity of diclofenac was conducted. Nanocapsule and nanosphere suspensions were prepared by nanoprecipitation and freeze-dried after the addition of colloidal silicon dioxide. The powders were examined under scanning electron microscopy (SEM) and gastrointestinal tolerance of products was evaluated in rats. Powders presented drug contents between 90.2+/-5.5 and 101.1+/-1.9% (HPLC). SEM analyzes showed non-spherical microparticles and, at higher magnifications, the micro-powder surface presented a homogeneous nanocovering. Regarding the gastrointestinal tolerance, with the exception of benzyl benzoate-loaded formulations, powders presented lesional indexes lower than the diclofenac salt solution. In contrast to the literature, nanocapsules can be dried by freeze-drying without leakage of drug or breaking the capsule wall. 相似文献
995.
Meiosis was examined in pollen mother cells of F1 hybrids made from crosses between wheat (Triticum aestivum) and lymegrass (Leymus arenarius and L. mollis). Fluorescence genomic in situ hybridization detected pairing between wheat and lymegrass chromosomes during prophase I and metaphase I. Such pairing, when resulting in bivalent formation, was likely to yield correct disjunction, and hence intergenomic recombination could be incorporated into the gametes. Bivalents in these hybrids, however, were more frequently formed between chromosomes of the same parental origin. Univalents were common, whereas multivalents were not clearly detected. Meiotic behaviour in some cells was not totally aberrant, and this may have accounted for the presence of normal pollen. The results are discussed in relation to intergenomic pairing, meiotic behaviour in wide-hybrids and genome relationships, including the Leymus genome origin. 相似文献
996.
M. E. Locatto V. Di Loreto M. C. Fernández D. Caferra R. C. Puche 《Acta diabetologica》1997,34(3):211-216
This report deals with the relationships between glucose (G) and insulin on the tubular transport of phosphate (P) in chronically
diabetic rats with high plasma levels of parathyroid hormone (PTH). Alloxan-induced diabetes leads to phosphorus depletion
of the soft tissues. This phenomenon appears associated with weight loss and negative P balances caused by the increased urinary
P excretion. Administration of 2 IU of insulin/100 g body weight (bw) to diabetic rats normalized their P balance and body
weight. The effect of parathyroid function on the P metabolism of diabetic rats was investigated with balance experiments.
Diabetic rats, intact or thyroparathyroidectomized (TPTX), have a greater urinary excretion of P than their controls. However,
in control rats, the ratio intact:TPTX for urinary P is 1.0:0.76, showing the antiphosphaturic effect of parathyroid ablation.
For diabetic animals, on the other hand, the ratio is 1.0:1.44. The simultaneous deficit of insulin and PTH thus quadruples
the urinary P loss, instead of compensating for each other. The contribution of insulin deficit and hyperglycemia to the defect
in tubular reabsorption (TRP) was investigated with clearance experiments (done on anesthetized, perfused rats). Five experimental
groups were used: Controls (C), diabetics (D), controls+glucose (C+G), diabetics+insulin (D+I) and diabetics+insulin+glucose
(D+I+G). All experimental groups showed a linear relationship between the TRP of P and G. The regression equation for C is
significantly different (F=40.1, P<0.001) from that of D animals. The slope value measure the number of μmoles of P per μmol of G reabsorbed. For C and D rats,
the ratio P:G approximates 1:4 and 1:20, respectively. The increase in P:G ratios represents the competition between both
substrates for tubular resorption. Glycemias up to 11 mM (C and D+I) exist concurrent with the P:G ratio 1:4. Glycemias above
25 mM (D, C+G and D+I+G) produce a P:G ratio of 1:20. Fractional excretion of P (FEP) increased significantly in untreated,
chronically diabetic rats (0.47± 0.12 vs controls=0.05±0.01, P<0.001). After a single intramuscular injection of insulin, the FEP decreased as a function of insulin levels. To normalize
the FEP of diabetic rats in short-term experiments, insulin had to be administered in doses that produce plasma insulin levels
25 times greater than normal. The general information afforded by the present experiments shows that in untreated, chronically
diabetic rats, insulin deficit plays an indirect role. The absence of PTH enhances the effect of hyperglycemia. The latter
and the concurrent tubular overload of glucose are the cause of hyperphosphaturia in these animals.
Received: 10 September 1996 / Accepted in revised form: 18 April 1997 相似文献
997.
R. M. Escorihuela A. Fernández-Teruel A. Tobeña W. Langhans K. Bättig P. Driscoll 《Behavior genetics》1997,27(6):573-578
An inbreeding program has been carried out with the Swiss sublines of Roman high- and low-avoidance rats since 1993. The present study reports the first experiments conducted with young animals of those inbred strains (RHA-I/Verh and RLA-I/Verh, respectively) from the sixth and seventh inbreeding generations. The results confirmed expected behavioral profiles. Compared to the RHA-I/Verh strain, RLA-I/Verh rats showed decreased entries into the illuminated central arena of an hexagonal tunnel maze, as well as decreased spontaneous locomotor activity and increased defecations, in two independent experiments. Young RLA-I/Verh females explored less than did their RHA-I/Verh counterparts during session 1 of a conditioned-fear experiment preceding shock administration, and in session 2 (conducted 24 h after the application of three footshocks), they showed greater conditioned behavioral inhibition (i.e., reduced amount of rearing), as well as higher defecation scores, than did RHA-I/Verh females.Karl Bättig tragically and unexpectedly died on December 27, 1996 相似文献
998.
M. Castro-Gago E. Cid Fernández J. Eirís Puñal P. Pavón Belinchón A. Rodríguez-Nuñez S. Rodríguez-Segade F. Camiña Darriba 《Child's nervous system》1996,12(6):315-317
Adenosine monophosphate, inosine monophosphate, inosine, adenosine, guanosine, adenine, guanine, hypoxanthine, xanthine and uric acid were determined in cerebrospinal fluid (CSF) of 15 children after complex febrile seizures (CFS) and in 27 after simple febrile seizures (SFS), and compared with those in a control group of 63 children. There was no statistically significant difference between the groups for any of these metabolites, suggesting that CFS and SFS neither significantly disturb the metabolism of nucleotides, nucleosides or bases nor significantly deplete neuron adenosine triphosphate levels. 相似文献
999.
Concepción González Inmaculada Pascual Angeles Bacete and Antonio Fimia 《Ophthalmic & physiological optics》1996,16(1):19-30
By applying Seidel aberration theory we have studied the spherical aberration of intraocular lenses in place ( S IL ), and the total spherical aberration of pseudophakic eyes ( S IT ). The optimum lens shapes for zero S IL and S IT or for minimum S IL and S IT of 12 schematic, highly myopic eyes were investigated. When the power required for emmetropization is positive, the total Seidel spherical aberration of the whole eye cannot be zero but can only be minimized. If the power of the intraocular lens is negative, the total Seidel spherical aberration of the whole eye can be made zero, and one of the optimum lens shapes would be meniscus with the convex surface towards the retina. In addition to improving the quality of the image, the lens has advantages from the physiological point of view, since it helps to maintain the structure of the eye. 相似文献
1000.
The diagnostic problems of metastases and recurrences in colorectal tumour patients are reviewed. The question and indications of relaparotomies are discussed in detail. The results of relaparotomies made for tumorous and nontumorous indications at the Department of Surgery of the National Cancer Institute are reported. 相似文献