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61.
Hepatocarcinogenesis was initiated in rats with a single dose of either of two chemical mutagens--benzo[a]pyrene diolepoxide I and methyl(acetoxymethyl)nitrosamine--administered 15 h after partial hepatectomy. The development of hepatocellular foci and neoplasms was then promoted with dietary phenobarbital given for 45 or 62 weeks. Formalin-fixed tissue specimens that contained hepatic neoplasms and altered hepatocellular foci were screened for expression of the oncodevelopmental marker glutathione-S-transferase (placental form) (GSTP) and transforming growth factor-alpha (TGF-alpha) using immunohistochemistry. All (100%) hepatocellular carcinomas expressed both GSTP and TGF-alpha, as did most hepatocellular adenomas (greater than 80%). However, quantitative stereologic analysis of treated and control livers revealed that GSTP-positive foci were 10-30 times more frequent than TGF-alpha-positive foci. Foci with homogeneous expression of GSTP generally displayed heterogeneous expression of TGF-alpha with reaction product most prominent at their peripheries. Less frequently homogeneous TGF-alpha-positive foci were seen within GSTP-positive foci. The average volumes of those GSTP-positive foci that also expressed TGF-alpha were significantly greater than those of the entire sets of GSTP-positive foci. These results suggest that expression of TGF-alpha may distinguish a subset of GSTP-positive foci that have a growth advantage and increased probability of progression to neoplasia.  相似文献   
62.
63.
Attention is drawn to the relatively rare and poorly appreciated clinical featues of entrapment of the superficial sensory branch of the radial nerve (SBR) in the forearm. In a series of 15 patients with cheiralgia paresthetica, alleviation of pain and discomfort was achieved in 66.6% of the conservatively-treated patients and in 80% of the five non-responsive patients who required neurolysis of the nerve. Job-related symptoms were exhibited by 33.3% of the patients, which subsided upon job modification or less hand-intensive work and conservative treatment. We suggest that modalities of treatment should be appropriate for the pathophysioloy of the SBR injury, while early recognition of the syndrome reduces the necessity for surgery.  相似文献   
64.
Botulinum A toxin (BOTOX®) was injected into the gastrocnemius muscle of 26 cerebral palsy subjects with equinus gait. All subjects were equinus walkers without fixed contracture of the triceps-surae muscle. Injections were performed at 3 month intervals, if needed, as determined by the treating clinician. There were 14 subjects with spastic hemiplegia, 11 subjects with spastic diplegia and 1 subject with spastic quadriplegia. In the case of those subjects with bilateral equinus gait the dose was divided and given into both the right and left gastrocnemius muscle. Gait analysis data was collected prior to the first injection and subsequently at 3 month intervals for 1 year. Kinematic and electromyographic data was obtained. This data was analyzed to provide objective information about the outcome of treatment. Four subjects moved away and were lost to follow-up. Seven subjects left the study to have surgery. The data collected revealed statistically significant improvements in dynamic ankle dorsiflexion in both stance and swing phases, stride length, and electromyography of the tibialis anterior. There were no complications. While the results of this study are promising, additional prospective studies are needed to determine the feasibility of preventing muscle contractures over a longer time period. Furthermore, there is a need for inclusion of other muscles in future research. Future research should also compare BOTOX® treatment with alternative methods of dealing with muscle spasticity such as: casting, orthotic devices, physical therapy, selective dorsal rhizotomy, and surgical lengthening.  相似文献   
65.
Objective: To determine if uncooked cornstarch, as part of the evening snack, can avert nocturnal hypoglycemia in type 1 diabetes. Research Design and Methods: Fifty-one campers and counselors at the American Diabetes Association Camp in San Bernardino, CA were randomly assigned to receive 5 g of uncooked cornstarch as part of the 21:00 evening snack vs. a standard snack of equivalent carbohydrate content. Each snack was given for five nights and the participants and medical personnel were blinded as to assignment. Midnight and 07:00 finger stick blood glucose levels were compared with values <60 mg/dl defined as hypoglycemia and values >250 mg/dl defined as hyperglycemia. Results: There were 218 midnight and 222 07:00 values for comparison. There were six episodes of hypoglycemia at midnight and nine episodes of hypoglycemia at 07:00 for the cornstarch snack nights vs. 30 hypoglycemia episodes at midnight and 21 at 07:00 for the standard snack nights (P < 0.001 and < 0.05, respectively). There was no difference in the number of hyperglycemic events at midnight or 07:00 for the cornstarch vs. standard snack nights. At midnight, 12% of campers had hypoglycemia after the cornstarch snack vs. 46% after the standard snack (P < 0.001), and at 07:00, 16% had hypoglycemia after cornstarch vs. 26% after the standard snack (P = 0.327). Conclusions: These data suggest that uncooked cornstarch, as part of the evening snack, can diminish the nighttime and morning hypoglycemia associated with type 1 diabetes, without causing hyperglycemia.  相似文献   
66.
In a randomized, double-masked study, 41 patients with primary open-angle glaucoma or ocular hypertension were treated with betaxolol 0.5% or timolol 0.5% drops for 26 weeks. The average decrease in intraocular pressure (IOP) over the total study period was significant with both betaxolol (-6.3 mmHg) and timolol (-7.2 mmHg) in patients receiving no adjunctive therapy. There was no difference between betaxolol and timolol with respect to changes from baseline IOP. Significantly decreased mean brachial arterial pressure (MAP) was seen only with timolol, although the difference between the two groups was not significant. Pulse, pupil size, and basal tear secretion were unchanged in both groups. Burning upon instillation of the drops was more frequent with betaxolol.  相似文献   
67.
Toxic shock syndrome has been associated with rhinologic surgery and medical devices, and it has been linked to a circulating exotoxin of a toxogenic strain of Staphylococcus aureus. One hundred forty patients with rhinosinusitis were studied. Nasal cultures were obtained. The microbiological characteristics are described. The carrier rate for Staphylococcus aureus was 35%. Thirty percent of patients selected for surgery were Staphylococcus aureus carriers. Toxin-capable isolates were identified in 40% of those tested. Users of cocaine, topical decongestants, and steroid sprays had a statistically higher rate of Staphylococcus aureus carriage compared to non-users. It is hoped that by identifying the population at risk and defining the factors associated with the development of toxic shock syndrome, a cogent policy of prevention can be established.  相似文献   
68.
Mammalian response to subdermal implantation of textured microimplants   总被引:4,自引:0,他引:4  
The development of small, textured implant particles suspended in a hydrogel has allowed for subdermal injection therapy to fill tissue defects. The microimplant particles were placed subdermally into the ears of white New Zealand rabbits in order to characterize the foreign body response and the permanence of the implant. Serial micrometer readings were performed on the implant sites to determine any change in thickness of the augmentation following baseline measurement. An initial increase in the thickness was noted approximately 20–30 days postimplantation, as expected. A stable thickness was noted for the remainder of the experiment. Serial histological sections were performed at irregular intervals from one week to one year. Histology demonstrated a mild foreign body response with collagen surrounding each individual microimplant particle. The response was stable after 30–40 days and has remained stable for over one year. It was determined that the histology demonstrated a Boros IA type, or nonimmunogenic, low-turnover foreign body reaction.  相似文献   
69.
We have previously demonstrated in a rat model that the lumbar intrathecal injection of 0.02 ml 6.3% magnesium sulphate, a concentration iso-osmolar with rat plasma, produces a state of spinal anaesthesia and general sedation which reversed completely after 6 h, without evidence of neurotoxicity, immediately or during the week thereafter. Using the same model and five groups of six animals in each, we administered the same volume and concentration of magnesium sulphate and compared its clinical effects with those of 0.02 ml 12.6% magnesium sulphate, 0.02 ml 2% lignocaine and 0.02 ml 0.9% sodium chloride solution, given as a series of 15 injections on alternate days for a period of 1 month. The animals were then killed and their spinal cords and meninges examined histologically. No significant differences were noted in the times of onset, durations of sensory and motor blockade and the times to full recovery throughout the entire period of 1 month's observation in the animals receiving intrathecal 6.3% magnesium sulphate. In the group receiving 12.6% magnesium sulphate, the time of onset of sensory and motor blockade was shorter and the duration of both parameters was significantly longer than in the former group. Full clinical recovery and resumption of normal eating and drinking took place in both groups throughout the entire series of 15 successive intrathecal injections. Identical, mild, uniform histopathological changes in the spinal cord were seen in all the five groups, including the group in which only the intrathecal catheter was implanted. The complete recovery and benign consequences of repeated intrathecal injections of iso-osmolar magnesium sulphate in a rat model indicate a lack of neurotoxicity and provide an impetus for further trials in larger animal species, before initial clinical trials of this substance, given intrathecally, in humans.  相似文献   
70.
Our previous studies have shown that the in vitro assay of donor antigen-specific hyporeactivity is a useful marker for identifying solid organ transplant recipients (kidney, lung and heart) at low risk for immunologic complications (i.e., late acute rejection episodes and chronic rejection). Donor antigen-specific hyporeactivity is defined as a significantly decreased post- vs. pretransplant proliferative response to donor antigens while response to third-party controls remains unchanged. We analyzed whether exposure to the same HLA-DR antigen pretransplant via random blood transfusion and posttransplant via the transplanted organ influenced the development of hyporeactivity. Thirty previously nontransfused recipients, each receiving two 150 ml pretransplant random blood transfusions, were assessed for hyporeactivity at 1 year posttransplant. Of the 12 recipients with pretransplant exposure to kidney HLA-DR via transfusions, 6 (50%) developed hyporesponsiveness; in contrast, of the 18 recipients who were not preexposed, only 3 (15%) exhibited this form of immunomodulation. Of interest, 2 of the 3 hyporesponsive recipients who were not preexposed, received units containing HLA-DR antigens previously shown to share crossreactive epitopes with the kidney HLA-DR. In conclusion, these results suggest a increased incidence in the development of hyporeactivity in patients receiving pretransplant transfusions which share an HLA-DR antigen with the transplanted kidney.  相似文献   
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