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991.
We report our experience with 9 cases of brain stem cavernoma in children aged 15 years during the period 1987-2000. All patients were admitted with lesion-related symptoms, except in one where the brain stem cavernoma was discovered on a routine MR scan. A female predominance was noted in the present study. In 2 children, brain stem cavernoma was associated with multiples lesions. All patients except two with multiple cavernomas underwent surgery. One child died 2 months after surgery from recurrent hemorrhage. The eight others are alive. Among the 8 survivors, only one has worsened. Children with brain stem cavernoma who develop persistent or progressive deficit are candidates for surgery. When surgery is indicated, total removal is mandatory to avoid the risk of recurrence and rebleeding.  相似文献   
992.
The cost of bladder tumour treatment and follow-up   总被引:2,自引:0,他引:2  
OBJECTIVE: To evaluate the costs of bladder tumour treatment and follow-up. MATERIAL AND METHODS: The incidence of bladder tumours, both new and recurrences, and the cost of bladder tumour treatments with curative intent were registered during a 4-year period (1994-97). RESULTS: The incidence of new tumours varied from year to year, in contrast to the number of recurrent tumours, which remained remarkably stable. The total cost of bladder cancer diagnosis, treatment and follow-up was almost 7,000,000 SEK per year (2,800,000 SEK per 100,000 inhabitants per year). The number of therapeutic events per year remained stable at 256 +/- 17 (102 per 100,000 inhabitants per year). Cystectomies were responsible for 34% of the expenditure and transurethral procedures for 40%. Follow-up cystoscopies accounted for only 13% of the total cost. One-third of the routine follow-up cystoscopies resulted in a therapeutic procedure. The cost of transurethral resections and extirpations was approximately five times higher when performed with the patient hospitalized compared to when performed as day-care surgery. CONCLUSIONS: A reduction in the number of follow-up cystoscopies will only produce marginal economic savings. Further savings could be made if more transurethral resections and extirpations/fulgurations were performed on an outpatient basis. Another important goal is to reduce the median cost per cystectomy.  相似文献   
993.
Carneiro DM  Irvin GL  Inabnet WB 《Surgery》2002,132(6):1050-4; discussion 1055
BACKGROUND: Familial isolated primary hyperparathyroidism (FIHPT) is characterized by earlier onset, higher incidence of multiglandular disease, and higher recurrence rate when compared with sporadic primary hyperparathyroidism. Excision of 3.5 or 4 glands with autotransplantation has been recommended; however, these approaches lead to permanent hypoparathyroidism in 13% to 41% of patients. It is reported that many patients with FIHPT return to normocalcemia after single-gland excision. The use of preoperative localization and intraoperative parathyroid hormone assay permits limited resection of only hypersecreting glands. We report the outcome of this operative approach. METHODS: Fifteen consecutive patients with FIHPT underwent limited parathyroidectomy with resection guided by intact parathyroid hormone secretion in 2 university centers. Patients were followed up postoperatively for serum calcium and intact parathyroid hormone levels. RESULTS: With an operative success of 93%, 14 patients had only single-gland excision and 80% had unilateral neck exploration. All initial patients had their hypercalcemia corrected. In 4 reoperations, permanent hypoparathyroidism occurred in 2 patients. One recurrence was observed in 40 (8-122) months of follow-up. CONCLUSION: Limited parathyroidectomy allows successful single-gland excision in many patients with FIHPT, thus decreasing the risk of hypoparathyroidism. In these patients, a low incidence of hypoparathyroidism may be preferable to the possibility of late recurrence.  相似文献   
994.
BACKGROUND: Anti-CD3 immunotoxins are broad-spectrum immunosuppressive agents in a wide range of organ transplantation animal models with potential use in eliciting antigen-specific tolerance. However, the anti-CD3 immunotoxins used in animal studies do not cross-react with human T cells, limiting extrapolation to humans and hindering clinical development. METHODS: Three anti-human CD3-directed immunotoxins, DT389-scFv(UCHT1), scFv(UCHT1)-PE38, and UCHT1-CRM9, were compared in vitro and in transgenic mice, tg(epsilon)600+/-, that have T cells expressing both human and murine CD3epsilon antigens. RESULTS: These immunotoxins were extraordinarily potent in vitro against human or transgenic mouse T cells, with IC50 values in cellular assays ranging from pM to fM. Systemic administration of these immunotoxins dose-dependently depleted >99% of tg(epsilon)600+/- lymph node and spleen T cells in vivo. Depletion was specific for T cells. The loss of the concanavalin A-induced, but not the lipopolysaccharide-induced, splenic proliferative response from immunotoxin-treated animals further demonstrated specific loss of T-cell function. Immunotoxin treatment prolonged fully allogeneic skin graft survival in tg(epsilon)600+/- recipients to 25 days from 10 days in untreated animals. T-cells recovered to approximately 50% of normal levels after approximately 22 days in animals with or without skin grafts; T-cell recovery correlated with skin graft rejection. All three immunotoxins elicited >100 day median survival of fully allogeneic heterotopic heart grafts. By 100 days, T cells recovered to normal numbers in these animals, but the grafts showed chronic rejection. CONCLUSION: These immunotoxins profoundly deplete T cells in vivo and effectively prolong allogeneic graft survival.  相似文献   
995.
996.
Acne treatment with a 1,450 nm wavelength laser and cryogen spray cooling   总被引:8,自引:0,他引:8  
BACKGROUND AND OBJECTIVES: A laser with a wavelength in the mid-IR range targeting the depth in skin where sebaceous glands are located in combination with cryogen spray cooling was evaluated for treatment of acne. In this non-ablative treatment, the laser energy heats the dermal volume encompassing sebaceous glands whereas the cold cryogen spray preserves the epidermis from thermal damage. STUDY DESIGN/MATERIALS AND METHODS: Monte Carlo simulations and heat transfer calculations were performed to optimize the heating and cooling parameters. A variety of heating and cooling parameters were tested in an in vivo rabbit ear study to evaluate the histological effect of the device on sebaceous glands and skin. Similar experiments were performed on ex vivo human skin. A clinical study for the treatment of acne on backs of human males was also conducted. RESULTS: Monte Carlo simulations and heat transfer calculations resulted in a thermal damage profile that showed epidermal preservation and peak damage in the upper dermis where sebaceous glands are located. Ex vivo human skin histology confirmed the damage profile qualitatively. In vivo rabbit ear histology studies indicated short-term thermal alteration of sebaceous glands with epidermal preservation. In the human clinical study on the back, a statistically significant reduction in lesion count on the treated side compared to the control side was seen (p < 0.001). Side effects were transient and few. CONCLUSIONS: The studies reported here demonstrate the feasibility of treating acne using a photothermal approach with a mid-IR laser and cryogen cooling.  相似文献   
997.
998.
BACKGROUND: Compared with the postprandial events after a single meal, different events occur when a second meal is ingested 4-6 h after a first meal. There is a rapid appearance of chylomicrons in the circulation carrying fat ingested with the first meal, with a peak 1 h after the second meal. OBJECTIVE: Our goal was to examine whether different dietary oils have effects on the storage of triacylglycerol as a result of differences in their digestion, absorption, and incorporation into chylomicrons. DESIGN: A single-blind, randomized, within-subject crossover design was used to study the effects of palm oil, safflower oil, a mixture of fish and safflower oil, and olive oil on postprandial apolipoprotein (apo) B-48, retinyl ester, and triacylglycerol in the S(f) > 400 fraction with the use of a sequential meal protocol. RESULTS: For triacylglycerol, retinyl ester, and apo B-48, the time to reach peak concentration was significantly earlier after the second meal than after the first meal (P < 0.005). This was apparent with each of the dietary oils. The pattern of the apo B-48 response differed significantly among the dietary oils, with olive oil resulting in higher concentrations after both meals (P = 0.003). The ratio of triacylglycerol to apo B-48 was significantly lower after olive oil feeding than after feeding with the other oils (P = 0.02). CONCLUSIONS: The rapid entry of chylomicrons after the ingestion of a second meal 5 h after a first meal was seen with all of the oils investigated. The short-term ingestion of olive oil produced more chylomicrons than did the other dietary oils, which may have been due to differences in the metabolic handling of olive oil within the gut.  相似文献   
999.
BACKGROUND: Vagal stimulation combined with an oral fat load enhances postprandial lipemia in animals and humans. OBJECTIVE: We assessed whether the observed postprandial increase in plasma lipids could be explained by changes in exogenous (chylomicron) or endogenous (VLDL) lipid metabolism and whether the timing of vagal stimulation in relation to fat intake was important. DESIGN: Vagal stimulation was achieved by using the modified sham feeding (MSF) technique, in which food is tasted and chewed but not swallowed. Seven healthy men consumed an oral fat load (50 g) on one occasion (control protocol). On 2 other occasions, they consumed an oral fat load combined with MSF of an appetizing meal. MSF was performed for either 1 h before or 1 h after the oral fat load. Blood was collected for 7 h and was analyzed for hormones and metabolites. RESULTS: The postprandial triacylglycerol response differed significantly (P < 0.001) between the 3 protocols. Both MSF studies resulted in significantly higher plasma pancreatic polypeptide concentrations compared with the control. Compared with MSF for 1 hour after fat intake, MSF for 1 h before fat intake resulted in significantly higher plasma insulin concentrations (P = 0.013), a more rapid rise in chylomicron triacylglycerol concentrations (P = 0.04), and higher VLDL triacylglycerol and apoliprotein B-100 concentrations. CONCLUSIONS: Vagal stimulation enhanced postprandial lipemia via effects on both chylomicron and VLDL metabolism. MSF before fat intake had more dramatic effects on postprandial lipemia than did MSF after fat intake, possibly because of increased parasympathetic activity at the time of ingestion.  相似文献   
1000.
BACKGROUND: Corn masa flour is widely consumed in Central America and is therefore a potentially useful vehicle for iron fortification. OBJECTIVE: The goal was to evaluate the bioavailability of iron from meals based on corn tortillas and black bean paste that were fortified with ferrous fumarate, ferrous sulfate, or NaFeEDTA and to investigate the potential of Na(2)EDTA to increase the bioavailability of iron from ferrous fumarate. DESIGN: With use of a crossover study design, iron bioavailability was measured in Guatemalan girls aged 12-13 y by a stable-isotope technique based on erythrocyte incorporation 14 d after intake. RESULTS: Geometric mean iron bioavailability from test meals fortified with ferrous fumarate was 5.5-6.2% and was not improved significantly by the addition of Na(2)EDTA at molar ratios of 1:1 relative to fortification iron or to the total iron content of the fortified corn masa flour. Geometric mean iron bioavailability from test meals fortified with ferrous sulfate was 5.5% and was significantly higher in test meals fortified with NaFeEDTA (9.0%; P = 0.009, paired t test). CONCLUSIONS: The bioavailability of iron from ferrous fumarate was not improved by the addition of Na(2)EDTA, contrary to what was previously shown for ferrous sulfate in other cereal-based meals. However, the bioavailability of iron from the test meal was significantly enhanced when NaFeEDTA replaced ferrous sulfate. These results support the use of NaFeEDTA in the fortification of inhibitory staple foods such as corn masa flour.  相似文献   
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