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11.
The intervertebral disc is characterized by a tension-resisting annulus fibrosus, and a compression-resisting nucleus pulposus composed largely of proteoglycan. Both the annulus and the nucleus function in concert to provide the disc with mechanical stability. Early disc degeneration begins in the nucleus with proteoglycan depletion. Quantitative MRI techniques have been developed to non-invasively quantify the earliest degenerative changes that occur within the disc. Our ability to identify and quantify these early biochemical changes will provide a better understanding of the pathophysiology of disc degeneration and facilitate the study of interventions that aim to halt or reverse the degenerative process.  相似文献   
12.
As demand for donor pancreases increases, attempts are being made to utilize even marginal grafts for transplantation. Injury during pancreas recovery can predispose to posttransplant complications and graft loss. Early recognition and correction can salvage these grafts. The authors report an instance of poor segmental perfusion of the pancreas graft that was salvaged by pancreas head resection and enteric drainage through a Roux-en-Y pancreatico-jejunostomy.  相似文献   
13.
Incisional hernias occur in up to 17% of patients after liver transplantation. Laparoscopic ventral hernia repair is associated with fewer wound complications and a decreased incidence of recurrence when compared to open hernia repair in nontransplant patients. This is a retrospective review of 13 patients who underwent laparoscopic incisional hernia repair (LAP group) after liver transplantation compared to 14 patients who had open repairs (OP group; all but one with mesh). Primary immunosuppression in both groups at the time of transplantation was tacrolimus, but more patients in the LAP group were on sirolimus at the time of hernia, while more patients in the OP group were on prednisone at the time of hernia repair. All operations were completed with a laparoscopic approach; there were no conversions to open. Length of stay differed significantly between the 2 groups, with a mean of 5.4 days for the LAP group compared to 2.7 days in the OP group (0.0059). Complications occurred in 2 (15%) of the patients in the LAP group and 5 (36%) in the OP group. One patient in the LAP group required mesh removal to exclude causes of recurrent ascites, and 1 in the OP group for mesh infection. One (7.6%) of the patients in the LAP group developed a recurrence, compared to 29% (4) of the OP group (P =0.3259). In conclusion, laparoscopic incisional hernia repair is safe in patients after liver transplantation, with a low risk of infection or recurrence.  相似文献   
14.
P K Reddy  P H Lange 《Urology》1987,30(2):123-126
Cystoscopy using the flexible cystoscope was performed on 15 patients in the semiprone position. Ureteral catheters were placed to facilitate percutaneous nephrolithotomy in 8 patients, and indwelling ureteral stents were removed in 7. The procedure offers the urologist an additional technique in select situations.  相似文献   
15.
Changes in carbohydrate metabolism were studied in midgut gland, muscle, and gill tissues of marine prawn Penaeus indicus exposed to a sublethal concentration (0.3 ppm) of phosphamidon. A significant decrease in glycogen and pyruvate and an increase in lactate content were observed in all phosphamidon-exposed prawn tissues after 96 hr. An increase in phosphorylase a and aldolase activity levels suggested the increased formation of triose sugars during phosphamidon toxicity. LDH activity was considerably decreased and an increment in lactate content was observed which indicates reduced mobilization of pyruvate into the citric acid cycle. Glucose-6-phosphate dehydrogenase activity was considerably increased, suggesting the enhanced oxidation of glucose in the hexose monophosphate shunt pathway. Krebs cycle enzymes such as NAD-isocitrate dehydrogenase, succinate dehydrogenase, and malate dehydrogenase were found to be decreased, suggesting the impairment in mitochondrial oxidative metabolism due to the acute toxic impact of phosphamidon. Cytochrome-c oxidase and Mg2+ ATPase activity levels were also decreased considerably, suggesting impaired energy synthesis and breakdown during phosphamidon toxicity, as a result of reduced oxidation of glucose aerobically. The increase in acid and alkaline phosphatase activities indicates the enhanced breakdown of phosphate to release energy in view of inhibiton or impairment in the ATPase system during phosphamidon-induced stress. These results suggest that phosphamidon has a profound effect on the oxidative metabolism of prawn which results in the triggering of compensatory metabolic pathways for survivability.  相似文献   
16.
Background. Extensive questioning of patients with a wide variety of skin disorders led to the impression that nocturnal overheating was probably an important factor in the initiation and the perpetuation of many skin disorders. Methods. In order to test the hypothesis, 12 “clean-skinned” subjects (6M/6F) aged 18 to 45 years were monitored electronically every 30 seconds during an 8 hour sleep period (2300 to 0700 hours), sleeping under a standard 10 tog duvet. Results. All the subjects were too hot by 3 to 4°C. All showed changes in their EEG patterns with reduced REM sleep, increased awakenings, and all showed changes in their sleep stage patterns. In addition, they all showed evidence of increased sweating in the “heat-sink” area. Conclusions. The mechanisms where by such changes could be implicated in the precipitation and perpetuation of skin disease are discussed. “Lifestyle” modification as a very effective, noninvasive, therapeutic regime is recommended. Further research along these lines would probably be very valuable and instructive.  相似文献   
17.
The modified dorsal lithotomy position is excellent for radical pelvic operations. Use of modified Krauss arm supports as stirrups, along with pneumatic devices that intermittently compress the legs, significantly reduces postoperative morbidity in patients who undergo operations in this position.  相似文献   
18.
19.
Abstract Myotonic dystrophy type 1 (DM1) is an autosomal dominant disease caused by a trinucleotide repeatexpansion, cytosine-thymine-guanine (CTG)n, in the 3′ untranslated region of a gene encoding the myotonic dystrophy protein kinase (DMPK). To correlate CTG expansion and protein expression, we studied muscle specimens from 16 adult DM1 patients using three anti-DMPK antibodies for immunoblotting. We estimated the amount of the full-length DMPK (85 kDa) in muscle biopsies from normal controls and from DM1 patients carrying different (CTG)n expansions. We found that DMPK concentration was decreased to about 50% in DM patients’ muscles; the protein decrease did not seem correlated with the CTG repeat length. However, the fibre type composition in skeletal muscle seemed somehow to affect DMPK decrease, as the lowest level of the enzyme was found in patients with the lowest content of type 1 fibre.  相似文献   
20.
Defects involving the distal leg and foot are frequently encountered following various aetiological factors. Paucity of local tissue causes surgeons to resort to the retrograde peninsular flap, the cross leg flap or the free flap. With specific knowledge of perforators, the fasciocutaneous flap from the calf area can be transferred to the defect in a single stage based on skeletonised distal perforators. The surgical anatomy, flap planning and procedure have been detailed. Nineteen patients were treated during the period 1995 to 2005. The perforators were identified preoperatively by audio Doppler. The flaps were marked and dissected proximal to the defect skeletonising the distal perforators under loupe magnification and transferred to the defect in a single stage. The donor site was skin grafted. Out of 19 cases, 16 flaps healed uneventfully, one flap necrosed completely and in two cases there was marginal necrosis. The cases were followed up for 2-10 years with an average of 6 years. With detailed knowledge of perforators one can safely reconstruct distal moderate-size defects of the lower limb in a single stage, thus having the benefits of free tissue transfer without resorting to microsurgery. This technique has proved to be an advancement in the reconstructive repertoire allowing flaps of non conventional dimensions to be perfused by skeletonised perforators.  相似文献   
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