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41.
A short segment of the herpes simplex virus (HSV) DNA proximal IRL region hybridized to two doublet bands of EcoRI-digested human cellular DNA. The hybridization was abolished neither by increasing stringency conditions nor by inclusion of guanine-rich DNA in the hybridization mixture. Thus, the hybridization appeared to represent authentic base sequence homology between HSV DNA and middle repetitive human DNA. 相似文献
42.
Expression of the macrophage scavenger receptor, a multifunctional lipoprotein receptor, in microglia associated with senile plaques in Alzheimer's disease. 总被引:2,自引:1,他引:2
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The macrophage scavenger receptor is a multifunctional receptor whose ligands include oxidized low density lipoprotein (LDL), as well as several other polyanionic macromolecules. Although the capacity of the receptor to bind modified LDL has implicated it in the process of atherosclerosis, its physiological role remains uncertain. We have examined human brain for expression of macrophage scavenger receptor as part of ongoing studies of lipoprotein receptors in the central nervous system. The receptor is expressed on microglia, but not on astrocytes, neurons, or vessel-associated structures. In Alzheimer disease, there is strong expression of the scavenger receptor in association with senile plaques. 相似文献
43.
Dou Q; Tarnuzzer RW; Williams RS; Schultz GS; Chegini N 《Molecular human reproduction》1997,3(11):1005-1014
44.
Hormone therapy and affect 总被引:2,自引:0,他引:2
This study investigated the influence of hormone therapy on affect in a double blind crossover trial. The sample consisted of 49 women who had previously undergone hysterectomy and bilateral oophorectomy. Therapy consisted of 3 mth each of ethinyl oestradiol — 50 μg/day, levonorgestrel — 250 μg/day, “Nordial” — a combination of these two substances, and placebo. Affect was measured by the Hamilton Depression Rating Scale, verbal reports by women and self-ratings on visual analogue scales. Ethinyl oestradiol was found to have a beneficial influence on aspects of affect such as Hamilton scores, anxiety, irritability and insomnia.
The influence of hormones on Hamilton scores could be partly but not fully explained by the alleviation of hot flushes. Norgestrel showed less favourable changes initially but these tended to diminish by the third therapy month. Most of the women studied were not clinically depressed. Anxiety symptoms were the major features exhibited in the group of women investigated. The results of this study suggest that visual analogue rating scales are of questionable validity in assessing affect in patients without any appreciable psychiatric morbidity. 相似文献
45.
Rodgers KE; Girgis W; St Amand K; Campeau J; diZerega GS 《Human reproduction (Oxford, England)》1998,13(9):2443-2451
Adhesion formation is a major source of postoperative morbidity and
mortality. In this study, the ability of a variety of lazaroid formulations
[the antioxidant 21-aminosteroid PNU74006F (tirilazad) and the
non-steroidal 2-methylaminochroman derivative PNU83,836E] to reduce i.p.
adhesion formation in three rabbit models was examined. In initial studies,
PNU83836E was administered via Alzet miniosmotic pump to the site of
injury. In the sidewall and double uterine horn models, PNU83,836E was
administered via Alzet miniosmotic pump for the entire postoperative
interval. In the sidewall model, there was a dose- dependent reduction in
the area of the sidewall injury that was involved in adhesions. In the
double uterine horn model, PNU83,836E was administered via Alzet
miniosmotic pump to the area of injury for 1, 2, 3 or 7 days.
Administration for as little as 24 h after surgery significantly reduced
the extent of adhesion formation and the reduction was increased if it was
administered for longer. Further studies were conducted in which various
lazaroid formulations were administered as a bolus at the end of surgery.
In both the sidewall and double uterine horn models, administration of
either PNU83,386E (in citrate buffer) or PNU74006F (in cyclodextrin or
lipid emulsion vehicles) at the end of surgery reduced adhesion formation.
Administration of a bolus of PNU74006F 10 min prior to initiation of
surgery with or without additional treatment at the end of surgery further
increased its efficacy in the reduction of adhesion formation.
Administration of a minimum of 1.5 mg before and after surgery (3 mg total)
was required for maximal efficacy. These studies demonstrate that pre- and
postoperative administration of either a steroidal (PNU74006F) or
non-steroidal (PNU83,836E) lazaroid intraperitoneally reduced the formation
and reformation of postoperative adhesions in three animal models.
相似文献
46.
L M Cabalka B T Hyman C R Goodlett T C Ritchie G W Van Hoesen 《Neurobiology of aging》1992,13(2):283-291
Neurons in layer II of the entorhinal cortex consistently develop neurofibrillary tangles in Alzheimer's disease (AD). Experimental neuroanatomical studies have shown that these neurons give rise to the perforant pathway, a major excitatory projection to the hippocampal formation, which terminates in a discrete pattern in the outer portion of the molecular layer of the dentate gyrus. The distribution of two nerve terminal associated proteins, synaptophysin and NT75, was studied in the molecular layer of the dentate gyrus in AD and control cases to determine whether Alzheimer neuronal pathology is associated with loss of synaptic markers. In parallel studies, the effect of ablation of the entorhinal cortex in rats was evaluated. In AD as compared to controls, a decrease in synaptophysin immunostaining was evident in the terminal zone of the perforant pathway. NT75 nerve terminal immunostaining was too weak to interpret in the human hippocampal formation. Both synaptophysin and NT75 immunoreactivity were found in association with some neuritic plaques. In rats, entorhinal lesions resulted in diminished immunoreactivity for both synaptophysin and NT75 in the perforant pathway terminal zone. These results suggest that nerve terminal protein loss is a concomitant feature of neuronal pathology in AD. 相似文献
47.
Genome location of polyadenylated transcripts of herpes simplex virus type 1 and type 2 DNA. 总被引:4,自引:0,他引:4
The genome location of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) polyadenylated RNA has been studied by hybridization of herpesvirus-specific nuclear and cytoplasmic polyadenylated RNA to the Eco R, restriction enzyme fragments of herpesvirus DNA, which have been separated by agarose gel electrophoresis and transferred to nitrocellulose paper. For both HSV-1 and HSV-2 DNA, the nuclear and the cytoplasmic polyadenylated RNA are distributed on all the Eco RI fragments of the homologous DNA. In a heterologous system, total polyadenylated RNA from HSV-1-infected cells was annealed to the Eco RI fragments of HSV-2 DNA and vice versa. HSV-2 polyadenylated RNA hybridized to all fragments of HSV-1 DNA, and HSV-1 polyadenylated RNA hybridized to all but three of the fragments of HSV-2 DNA. These data indicate that the DNA base sequence homology between the two herpesvirus strains is dispersed throughout the genome and is not located in a single contiguous block. 相似文献
48.
Paul A. Knepper Ralph K. Losey Jennifer A. Collins David G. McLone Hyman G. Weinstein Moira Breen 《Neurobiology of aging》1983,4(2):163-168
The glycosaminoglycan distribution patterns of the cerebrospinal fluid (CSF) outflow pathway, dura mater and cerebral cortex of young New Zealand red rabbits and 1-, 3- and 12-week-old C-57 mice were identified by analyses of the glycosaminoglycan moieties and by the use of zone electrophoresis. The glycosaminoglycans were identified by specific degradation procedures, i.e., hyaluronate lyase, chondroitin ABC lyase, endo-gb-D-galactosidase and nitrous acid treatment. The CSF outflow pathway and dura mater glycosaminoglycan components were primarily hyaluronic acid and chondroitin sulfatedermatan sulfate, whereas the cerebral cortex glycosaminoglycan components were hyaluronic acid, chondroitin sulfatedermatan sulfate, keratan sulfate and heparan sulfate. The glycosaminoglycan components of the dura mater and cerebral cortex decreased and those of the CSF outflow pathway increased as a function of age. These results demonstrate the feasibility of analyses of the CSF outflow pathway glycosaminoglycan components and suggest that topographical changes in the glycosaminoglycan distribution profiles may contribute to the pattern of cerebrospinal fluid outflow. 相似文献
49.
Don V. Jackson Jr. V. Sagar Sethi Tony R. Long Hyman B. Muss Charles L. Spurr 《Cancer chemotherapy and pharmacology》1984,13(2):114-119
Summary The pharmacokinetics of vindesine were investigated during treatment of 15 patients with progressive malignancies refractory to conventional treatment. Patients were administered one of three IV dose schedules: 3.0 mg/m2 bolus injection, 1.2 mg/m2/day infusion for 5 days, or 2.0 mg/m2/day infusion for 2 days. Concentrations of the drug in the serum and urine were determined by radioimmunoassay. Serum concentrations were highest (5×10-7 M) in patients receiving a bolus injection, but fell to nondetectable levels by 48 h in four of five patients (terminal t1/2 15.0±9.4 h). Compared with bolus injection, 1.2-to 1.4-fold greater areas under the blood concentration curve were observed during infusions of 2.0 mg/m2 and 1.2 mg/m2. Whereas steady-state concentrations (1×10-8 M) were maintained throughout the infusion of 1.2 mg/m2/day progressively increasing serum levels were observed during the infusion of 2.0 mg/m2/day. Serum concentrations fell rapidly following discontinuation of the 2.0-mg/m2 infusion, but were somewhat more sustained in the 1.2-mg/m2 infusion group. The average urinary excretion was similar for each dose-schedule (8%–11% of the total dose). The pharmacokinetics of vindesine are influenced by variations in dose schedule. 相似文献
50.
Renal transplantation has become a treatment of choice for patients with end stage renal disease. A successful transplant is the result of a combination of several factors acting synergistically, such as the degree of HLA compatibility between donor and the recipient, pretransplant blood transfusions, the recipient''s state of immunoreactivity and sensitization, immunosuppressive therapy given in post operative period etc. Donor selection appears to be the most critical factor for the long term success of the organ graft. In this brief review, some of the important parameters of donor selection in renal transplantation are highlighted.KEY WORDS: Histocompatibility (HLA) matching, Cross match, Sensitization 相似文献