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Bone mineral density after resumption of menses in amenorrheic athletes   总被引:7,自引:0,他引:7  
B L Drinkwater  K Nilson  S Ott  C H Chesnut 《JAMA》1986,256(3):380-382
Amenorrheic athletes have been found to have a lower vertebral bone mineral density (BMD) than matched groups of eumenorrheic athletes. This study reports changes in BMD over a 15.5 month period in athletes who regained menses, athletes who remained amenorrheic, and athletes with regular cycles. The BMD was measured at two sites on the radius and at the lumbar vertebrae (L-1 through L-4), using single- and dual-photon densitometry, respectively. Changes in vertebral BMD were significant for the amenorrheic group (+6.3%), but not for cyclic women (-0.3%). A slight increase in radial density at S-1 and S-2 was not significant for either group. Two athletes who remained amenorrheic during this period continued to lose bone (-3.4%). We conclude that resumption of menses was the primary factor for the significant increase in the vertebral BMD of the formerly amenorrheic athletes.  相似文献   
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The serum antibody titers against Escherichia coli and/or Proteus mirabilis were elevated in 26 of 80 patients (33%) with a conduit urinary diversion. Urographic findings were abnormal in 44 of these 80 patients (55%). Urography was normal in 59% of the patients with normal antibody titers, but in only 15% of those with elevated titers. Raised antibody levels against E. coli O antigen (greater than 256 before and/or greater than 32 after mercaptoethanol treatment of serum) were associated with wide upper urinary tract or calculi more often than were normal E. coli antibody titers. Raised titers against P. mirabilis (greater than 256 before and/or greater than 32 after mercaptoethanol treatment of serum) were associated with scarring of the renal parenchyma more frequently than were normal titers. A statistically significant association was found between "small" kidney area and raised serum antibody titers against E. coli or P. mirabilis. The frequency of "small" kidney increased with the time lapse after urinary diversion. At 3 to 11 months postoperatively it was 29%, but among the patients with urinary diversion for more than five years the corresponding frequency was 82%. When at least one kidney was "small", the serum creatinine was higher than when both kidneys were of normal size. Patients with raised antibody titers tended also to have high serum creatinine (greater than or equal to 124 mumol/l) more often than those with normal titers (23 vs. 10%). These observations imply a connection between elevation of the antibody titers and destruction of the renal parenchyma in patients with conduit urinary diversion. They illustrate the value of antibody titration in the follow-up of patients with urinary diversion.  相似文献   
5.
The objective of this study was to examine the influence of chronic toxic encephalopathy (CTE) on Trail Making Test (TMT) performance, with special focus on the discriminative potential of this test. We assessed TMT performance in patients diagnosed with CTE, patients with similar symptoms but no diagnosis, and healthy participants. Inferior performance was seen in CTE, and increasing age had a negative effect on TMT performance only for the CTE group. This effect was most pronounced in TMT-B. However, the ability of the TMT to identify CTE was low, whereas all healthy participants were identified as healthy. Thus, the sensitivity of TMT alone was low, but it succeeded in correctly classifying normal subjects. The pattern of results indicates that normal TMT performance may be seen in individuals with mild to moderate brain syndromes, such as CTE, whereas poor performance should not be expected in healthy individuals.  相似文献   
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A transnasal, transsphenoidal surgical approach was used to perform hypothalamic pituitary disconnections (HPD) in ovariectomized (OVX) ewes to examine the role of the hypothalamus in regulating the synthesis of anterior pituitary hormones. Ewes were killed at 1-3 days (n = 6), 1 week (n = 5), or 1 month (n = 5) after HPD. Pituitary glands were removed, and hemisected for analysis of hormone or messenger RNA (mRNA) content. Blot hybridization using specific complementary DNA probes was used to quantify the concentration of mRNA for LH beta-subunit, alpha-subunit, GH, and PRL. Concentrations of mRNA for LH beta- and alpha-subunits were lower (P less than 0.01) at 1-3 days after HPD than in OVX ewes. At 1 week and 1 month after HPD, concentrations of mRNA for LH beta- and alpha-subunits were near the lower limit of detection of this assay system. In contrast, for 30 days after HPD, pituitary concentrations of mRNA for GH and PRL were not different (P greater than 0.05) from those in OVX ewes. At 1 week and 1 month after HPD, pituitary content of LH, FSH, and GH was lower (P less than 0.01) than in OXV ewes. Pituitary PRL content in all HPD ewes was lower (P less than 0.05) than in OVX ewes. In a separate group of five ewes that were bled daily for 30 days after HPD, serum concentrations of LH and FSH fell dramatically during the first 3 days after HPD. In contrast, serum concentrations of GH and PRL remained similar to pre-HPD concentrations for 30 days after HPD. Thus, hypothalamic stimulation is essential for maintaining the concentration of mRNA for LH beta- and alpha-subunits within the anterior pituitary gland. Without continued hypothalamic support, pituitary and serum concentrations of LH and FSH rapidly decline. In contrast, concentrations of mRNA for GH and PRL are maintained in the absence of hypothalamic input.  相似文献   
7.
The anti-inflammatory activity of Canavalia seed lectins (Canavalia gladiata [CGL], Canavalia maritima [ConM] and Canavalia brasiliensis [ConBr]) was evaluated by intravenous administration in rats. In non-sensitized rats, cellular edema elicited by carrageenan was reduced (45–51 %) by ConM and (44–59 %) by CGL. Osmotic edema elicited by dextran was reduced by ConM and CGL in 27 % and 29 %. ConM and CGL reduced the edema elicited by l-arginine in 53 % and that of prostaglandin E2 in 48 % and 36 %. Leukocyte migration elicited by carrageenan was reduced in 49 % by ConM and in 55 % by CGL (attenuated in 4× by glucose) and peritoneal TNF-α content in 82 %. In rats sensitized, ConM inhibited the paw edema and leukocyte migration elicited by ovalbumin in 34 % and 70 %. ConM and CGL are anti-inflammatory, mainly in cellular events mediated by prostaglandin E2, nitric oxide and TNF-α in non-sensitized rats. However, only ConM is anti-inflammatory in sensitized rats. CGL effect involves the lectin domain.  相似文献   
8.
During the last decades, advances in diagnosis and treatment of congenital heart disease have allowed many individuals to reach adulthood. Due mainly to the great diagnostic diversity and to the co-morbidities usually present in this age group, these patients demand assistance in a multidisciplinary facility if an adequate attention is aimed. In this paper we reviewed, based in the international literature and also on the authors’ experience, the structural conditions that should be available for these patients. We highlighted aspects like the facility characteristics, the criteria usually adopted for patient transfer from the paediatric setting, the composition of the medical and para- medical staff taking into account the specific problems, and also the model of outpatient and in-hospital assistance. We also emphasized the importance of patient data storage, the fundamental necessity of institutional support and also the compromise to offer professional training. The crucial relevance of clinical research is also approached, particularly the development of multicenter studies as an appropriate methodology for this heterogeneous patient population.  相似文献   
9.
Purpose: In vivo bone response was assessed by removal torque, hystological and histometrical analysis on a recently developed biomedical Ti‐15Mo alloy, after surface modification by laser beam irradiation, installed in the tibia of rabbits. Materials and Methods: A total of 32 wide cylindrical Ti‐15Mo dental implants were obtained (10 mm × 3.75 mm). The implants were divided into two groups: 1) control samples (Machined surface – MS) and 2) implants with their surface modified by Laser beam‐irradiation (Test samples – LS). Six implants of each surface were used for removal torque test and 10 of each surface for histological and histometrical analysis. The implants were placed in the tibial metaphyses of rabbits. Results: Average removal torque was 51.5 Ncm to MS and >90 Ncm to LS. Bone‐to‐implant‐contact percentage was significantly higher for LS implants both in the cortical and marrow regions. Conclusions: The present study demonstrated that laser treated Ti‐15Mo alloys are promising materials for biomedical application.  相似文献   
10.

Introduction

In vitro hydrodynamic characterization of prosthetic heart valves provides important information regarding their operation, especially if performed by noninvasive techniques of anemometry. Once velocity profiles for each valve are provided, it is possible to compare them in terms of hydrodynamic performance. In this first experimental study using laser doppler anemometry with mechanical valves, the simulations were performed at a steady flow workbench.

Objective

To compare unidimensional velocity profiles at the central plane of two bi-leaflet aortic prosthesis from St. Jude (AGN 21 - 751 and 21 AJ - 501 models) exposed to a steady flow regime, on four distinct sections, three downstream and one upstream.

Methods

To provide similar conditions for the flow through each prosthesis by a steady flow workbench (water, flow rate of 17L/min. ) and, for the same sections and sweeps, to obtain the velocity profiles of each heart valve by unidimensional measurements.

Results

It was found that higher velocities correspond to the prosthesis with smaller inner diameter and instabilities of flow are larger as the section of interest is closer to the valve. Regions of recirculation, stagnation of flow, low pressure, and flow peak velocities were also found.

Conclusions

Considering the hydrodynamic aspect and for every section measured, it could be concluded that the prosthesis model AGN 21 - 751 (RegentTM) is superior to the 21 AJ - 501 model (Master Series). Based on the results, future studies can choose to focus on specific regions of the these valves.  相似文献   
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