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71.
Many authors have questioned the gross anatomy of the septal papillary muscle of the conus known as the papillary muscle complex (PMC) during the past century. An anatomical investigation was conducted to identify the morphology and the topography of the PMC. Our study involved 200 formalin fixed adult human hearts. The PMC was present in 82% of the hearts, while in the remaining 18% of specimens, it was replaced by tendinous chords. The PMC was connected with the septal (59.7%), anterior (20.7%), or both septal and anterior leaflets (19.5%) with single (29.8%) or multiple chordae tendinae (70.1%). The PMC was also found to be present as a single papilla (51.8%), double papilla (32.9%) or triple papilla (15.2%). In addition to the PMC, we observed accessory single septal papillary muscles 42 specimens, double septal papillary muscles 32 specimens and triple septal papillary muscles 26 specimens. In the right ventricular inflow tract, the location of the PMC was consistently found to be in a position below the junction of the anterior and septal leaflets of the tricuspid valve. In the right ventricular outflow tract, we were able to identify 73 specimens in which the PMC was located at the junction formed superiorly by the inferior border of the subpulmonary infundibulum and inferiorly by the superior-lateral border of the septal band, extending into the region of the subpulmonary infundibulum. In the remaining 27%, the PMC was located primarily at the area occupied by the superiolateral border of the septal band without extending to the subpulmonary infundibulum. The present study describes the topography of the PMC according to its surrounding anatomical structures such as the tricuspid valve, subpulmonary infundibulum and septal band of the right ventricle. This anatomical data could have important clinical significance for cardiac surgeons operating in this area.  相似文献   
72.
Reconstruction of large bone defects is still a major problem. Tissue-engineering approaches have become a focus in regeneration of bone. In particular, critical-sized defects do not ossify spontaneously. The use of electrospinning is attracting increasing attention in the preparation of tissue-engineering scaffolds. Recently, acellular scaffolds carrying bioactive agents have been used as scaffolds in "in situ" tissue engineering for soft and hard tissue repair. Poly(epsilon-caprolactone) (PCL) with two different molecular weights were synthesized, and the blends of these two were electrospun into nonwoven membranes composed of nanofibers/micropores. To stimulate bone formation, an active drug, "simvastatin" was loaded either after the membranes were formed or during electrospinning. The matrices were then spiral-wound to produce scaffolds with 3D-structures having both macro- and microchannels. Eight-millimeter diameter critical size cranial defects were created in rats. Scaffolds with or without simvastatin were then implanted into these defects. Samples from the implant sites were removed after 1, 3, and 6 months postimplantation. Bone regeneration and tissue response were followed by X-ray microcomputed tomography and histological analysis. These in vivo results exhibited osseous tissue integration within the implant and mineralized bone restoration of the calvarium. Both microCT and histological data clearly demonstrated that the more successful results were observed with the "simvastatin-containing PCL scaffolds," in which simvastatin was incorporated into the PCL scaffolds during electrospinning. For these samples, bone mineralization was quite significant when compared with the other groups.  相似文献   
73.
74.
PURPOSE: To analyze whether the expression of matrix metalloproteinases (MMPs) and their tissue inhibitors are associated with tumor response to preoperative chemoradiotherapy in rectal cancer patients. METHODS AND MATERIALS: Forty-four patients who had undergone preoperative chemoradiotherapy were evaluated retrospectively. Treatment consisted of pelvic radiotherapy and two cycles of 5-fluorouracil plus leucovorin. Surgery was performed 6-8 weeks later. MMP-2, MMP-9, and tissue inhibitors of metalloproteinase-1 and -2 expression was analyzed by immunohistochemistry of the preradiation biopsy and surgical specimens. The intensity and extent of staining were evaluated separately, and a final score was calculated by multiplying the two scores. The primary endpoint was the correlation of expression with tumor response, with the secondary endpoint the effect of chemoradiotherapy on the expression. RESULTS: Preoperative treatment resulted in downstaging in 20 patients (45%) and no clinical response in 24 (55%). The pathologic tumor response was complete in 11 patients (25%), partial in 23 (52%), and none in 10 (23%). Positive MMP-9 staining was observed in 20 tumors (45%) and was associated with the clinical nodal stage (p = 0.035) and the pathologic and clinical response (p < 0.0001). The staining status of the other markers was associated with neither stage nor response. The overall pathologic response rate was 25% in MMP-9-positive patients vs. 52% in MMP-9-negative patients (p = 0.001). None of the 11 patients with pathologic complete remission was MMP-9 positive. CONCLUSIONS: Matrix metalloproteinase-9 expression correlated with a poor tumor response to preoperative chemoradiotherapy in rectal carcinoma patients.  相似文献   
75.
An example which confirmes the adequacy of the integrative perspective in medicine is depression in dermatology because of the sufficient number of arguments linking depression and some chronic skin conditions in depth more than simply comorbidity. In recent literature, the authors found, how depression in dermatology occurs significantly more frequently than in the general population. In dermatological patients the prevalence of depression is around 30% which is more in comparison to patients in general practice where prevalence of depression is 22%. The authors found a considerable similarity in the various characteristics between depression and psoriasis, based upon recent research findings in immunity disorder and elevated concentrations of proinflammatory cytokines as well as acute phase proteins in both disorders, indicating that both disorders can be considered as immunologicaly mediated, inflammatory states with repetitive chronic progress and similar comorbidity. The afore mentioned theoretical settings evoke the integrative aspect and the integrative interdisciplinary approach placing in the center of attention not only the diseased person with his fears, needs, preocupations and expectations during treatment, but the person who is at risk of becoming burdened with these disorders.  相似文献   
76.
The aim of this study was to determine the effects of fluid resuscitation of acute hemorrhage on the early function and histopathology of the remnant kidney in uninephrectomized rabbits. Thirty-nine adult rabbits were studied in four groups. Group 1 (n = 8) included healthy controls; Group 2 (n = 10) healthy, bled animals; Group 3 (n = 10) uninephrectomized, non-bled animals; and Group 4 (n = 11) uninephrectomized, bled animals. In the hemorrhage groups, 8 mL kg(-1) of blood was drawn, and replaced with lactated Ringer's solution three times the volume of shed blood. Urine and blood samples were collected after 120-minutes of observation. None of the animals experienced hypotension during the study period. Serum and urinary electrolytes were similar between the Groups (p > 0.05). Urine output was lower in Groups 3 and 4 than in Group 1 (p = 0.001, both). Urinary microalbumin, NAG, fractional sodium excretion and creatinine clearance were similar in all four Groups. Light microscopic evaluation revealed only slight enlargement of the proximal tubule lumen in the renal medulla of the rabbits that were both uninephrectomized and bled. We observed no deleterious effects of well resuscitated hemorrhage on early function and histopathology of the remnant kidney in uninephrectomized rabbits.  相似文献   
77.
Objective: To determine praxis function in patients with Parkinson’s disease (PD) and multiple system atrophy (MSA). Methods: Nineteen patients with PD and 16 patients with probable MSA were recruited into study. Twenty‐five age‐matched, healthy subjects were included as controls. The Mayo Clinic praxis test battery was applied. Pantomime tasks, including oral/facial, trunk, and upper extremity movement, were used to evaluate ideomotor apraxia (IMA). Sequential tasks, including Luria test for ideational apraxia (IDA) and use of actual objects, were also tested. In addition, Standardized Mini Mental Test (MMSE), Hamilton Depression (HAM‐D), and Anxiety (HAM‐A) Scales were used. Results: Mean ages of the study participants were 66 ± 7, 68 ± 5, and 65 ± 7 years in PD, MSA, and control groups, respectively. Mean total praxis score was significantly lower for patients with PD (92.4 ± 4) and MSA (75.9 ± 18) than for controls (97.4 ± 2) (P = 0.000). Transitive performances of upper extremities and sequential tasks were significantly impaired in patients with PD compared to control subjects (P < 0.05). There was no correlation between total praxis scores and sum scores of tremor, bradykinesia, and rigidity of both of the upper limbs of patients with PD. Subgroup praxis scores were substantially worse in MSA group (P < 0.0001). Compared to control subjects, mean scores for MMSE, HAM‐D, and HAM‐A tests were significantly worse in MSA group, but, for PD patient group, only HAM‐A scores were worse. Conclusion: Our results indicate that although not a presenting symptom, IMA and IDA may be features of MSA and, to a lesser degree, of PD. Also, it seems to be unrelated to the motor features of patients with PD.  相似文献   
78.
Eosinophilic cystitis is an unusual form of cystitis which is characterized by irritative voiding symptoms and haematuria. In the report herein two adult cases of eosinophilic cystitis treated with intravesical Mitomycin-C instillations for prophylaxis of bladder carcinoma are presented and the literature is reviewed.  相似文献   
79.
Cytokeratins (CKs) are expressed specifically in the cytoplasm of epithelial cells. We investigated the expression of CKs immunohistochemically in basal cell carcinomas (BCCs), epidermis overlying tumour, and skin tumor-associated amyloidosis (STA). Twenty cases of BCC, 11 of which had STA were included to the study. The primary antibodies of CK1-8 (AE3), CK10 (DEK-10), CK14 (LL002), CK17 (E3), CK18 (DC10), CK19 (KS19.1), CK 5/6/18 (LP34), CK8/18 (5D3) were applied to the section immunohistochemically. In BCCs without STA, CK1-8, CK14 and CK17 antibodies were expressed by tumour tissue in all biopsy specimens. In the BCCs with STA, tumour tissue was immunoreactive always with CK1-8 and CK17 antibodies, and commonly immunoreactive with anti-CK 14 antibody. In the epidermis overlying tumour tissue, there was positive immunoreactivity with anti-CK 1-8, CK 5/6/18, CK 10 and CK 14 antibodies in all biopsy specimens. Anti-CK 17 antibody was also positive in 17 biopsy specimens. STA is immunoreactive with anti-CK1-8 in all specimens. There was mild staining with anti-CK5/6/18 and with anti-CK19 whereas no immunoreactivity with anti-CK10 and CK18 antibodies was found. In conclusion, we could not find a significant CK expression difference between BCCs with and without STA. Weak positivity and a few number of CKs were shown in STA when compared with those of BCC and epidermis overlying tumour tissue expressing the more variable CKs. Interestingly, although CKs coexpressed in pairs consisting of one basic and one acidic CK, we detected predominantly basic CKs in STA.  相似文献   
80.
OBJECTIVE: To investigate the effects of angiotensin-converting enzyme (ACE) inhibitors and statins (hydroxy-methyl-glutaryl-CoA reductase inhibitors) on inflammatory markers and endothelial functions in patients with rheumatoid arthritis (RA). METHODS: A total of 45 patients with longterm RA were randomized into 3 groups to receive 8 weeks of treatment with placebo (n = 15), simvastatin (20 mg/day, n = 15), or quinapril (10 mg/day, n = 15) as an adjunct to existing antirheumatic drug treatment. Factors with a role in the development of endothelial dysfunction, such as C-reactive protein (CRP), fibrinogen, nitric oxide (NO), and serum cytokine concentrations including interleukin 1beta (IL-1beta), IL-6, and tumor necrosis factor-alpha (TNF-alpha) were measured at baseline and in the posttreatment period. Brachial artery vasodilator responses were assessed by high resolution ultrasound to evaluate endothelial functions. RESULTS: Simvastatin treatment significantly decreased serum CRP and TNF-a [from 14 +/- 6 to 7 +/- 3 mg/l (p = 0.025) and 30 +/- 5 to 16 +/- 4 pg/ml (p = 0.012), respectively], while quinapril had no significant changes in these 2 measures. IL-1beta and IL-6 showed insignificant changes in patients in the 2 drug groups. Endothelium-dependent vasodilatation was improved significantly in the simvastatin group [from 5.3 +/- 1.1% to 8.9 +/- 1.4% (p = 0.025)], while there was no difference in endothelium-independent vasodilatation [9.0 +/- 1.8% to 11.2 +/- 2.5% (p = 0.17)]. The quinapril group showed no significant changes in both types of vasodilation although there was a tendency to an increase in endothelium-dependent vasodilatation [from 6.1 +/- 0.8% to 7.8 +/- 0.7% (p = 0.06)]. Treatment with the 2 drugs had no significant effects on resting arterial diameter. CONCLUSION: We show that simvastatin 20 mg daily improves endothelial function in patients with RA. Its beneficial effect may be attributed to lowering CRP and TNF-alpha concentrations. ACE inhibition with daily 10 mg quinapril was found to have no significant effects on inflammatory markers and endothelial vasodilator response.  相似文献   
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