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91.
OBJECTIVE: To measure and evaluate the health-related quality of life (HRQOL) in patients with cutaneous T-cell lymphoma (CTCL), a visible cutaneous malignancy that may have a profound effect on patients' lives. DESIGN: Monocenter, cross-sectional study. SETTING: The Skin Oncology Program, Department of Dermatology, and the Photopheresis Unit of Boston Medical Center. PATIENTS: A total of 22 adult patients with confirmed CTCL. MAIN OUTCOME MEASURES: (1) Evaluation of general oncologic and skin disease-specific HRQOL using, respectively, the Functional Assessment of Cancer Therapy-General (FACT-G) and Skindex-29 profiles; (2) assessment of HRQOL association with disease stage (early stage, IA-IIA; late stage, IIB-IVB). RESULTS: Patients with more advanced CTCL stages reported more effects on general health (FACT-G), particularly in the physical, emotional, and functional domains (P < .05). Patients with early-stage CTCL reported better skin-specific HRQOL overall (Skindex-29; P = .002) and for each specific domain than did patients with late-stage disease. The Skindex-29 scales had high internal consistency, and the confirmatory factor structure was similar to that of previous studies. CONCLUSIONS: The HRQOL of patients with CTCL can be evaluated using the Skindex-29 and FACT-G instruments. Patients with more advanced stages of CTCL had lower HRQOL scores.  相似文献   
92.
Augmentation of tendon-bone healing by the use of calcium-phosphate cement   总被引:9,自引:0,他引:9  
The healing of a hamstring graft to bone is the weak link in the reconstruction of a cruciate ligament using this donor material. We therefore investigated the augmentation of healing at the tendon-bone interface using calcium-phosphate cement (CPC). We performed semitendinosus autograft reconstructions of the anterior cruciate ligament on both knees of 22 New Zealand white rabbits. The interface between the grafted tendon and the bone tunnel for one knee was filled with CPC. Six rabbits were killed at the end of the first and second post-operative weeks in order to evaluate the biomechanical changes. Two rabbits were then killed sequentially at the end of weeks 1, 3, 6, 12 and 24 after operation and tissue removed for serial histological observation. Histological examination showed that the use of CPC produced early, diffuse and massive bone ingrowth. By contrast, in the non-CPC group of rabbits only a thin layer of new bone was seen. Mechanical pull-out testing at one week showed that the mean maximal tensile strength was 6.505 +/- 1.333 N for the CPC group and 2.048 +/- 0.950 N for the non-CPC group. At two weeks the values were 11.491 +/- 2.865 N and 5.452 +/- 3.955 N, respectively. Our findings indicate that CPC is a potentially promising material in clinical practice as regards its ability to reinforce the fixation of the tendon attachment to bone and to augment the overall effectiveness of tendon healing to bone.  相似文献   
93.
STUDY OBJECTIVE: Sleep apnea and milder forms of sleep-disordered breathing (SDB) have been associated with overt clinical cardiovascular disease, but it is unknown whether SDB is associated with arterial microvascular pathology. We examined the relation between SDB and retinal microvascular abnormalities. DESIGN: Cross-sectional study. PARTICIPANTS: Subjects were 2,927 men and women, aged 51 to 97 years, who participated in the Sleep Heart Health Study and had retinal photographs taken within approximately 3 years of overnight, unattended, at-home polysomnography. MEASUREMENTS AND RESULTS: A respiratory disturbance index (RDI), calculated as the average number of apneas and hypopneas per hour of sleep, was used as an indicator of SDB in analysis. The overall prevalence of retinopathy was slightly higher in people with higher RDI values (5.4%, 4.9%, 8.6%, and 7.6%, respectively, in increasing quartiles of RDI), but after adjustment for age, body-mass index, hypertension, diabetes, and other factors, the presence of retinopathy was not associated with SDB. With the possible exceptions of microaneurysms and generalized arteriolar narrowing, as measured by lower arteriole-to-venule ratio, specific retinal abnormalities were not associated consistently with the RDI. Relative to the first quartile of RDI, the adjusted odds ratios (95% confidence interval) for the presence of microaneurysm in the second, third, and fourth quartiles of RDI were 1.05 (0.44-2.55), 1.97 (0.89-4.37), and 1.79 (0.78-4.10), respectively. An increase of RDI from 0 to 10 was associated with a predicted decrease in arteriole-to-venule ratio of 0.01. Results were similar when analyses were conducted in normotensive and nondiabetic persons separately. CONCLUSIONS: These data do not demonstrate a notable relation between SDB and retinal abnormalities. However, since this is the first investigation of a link between retinopathy and SDB, similar studies should be conducted in other population samples to demonstrate either consistency or inconsistency of our findings across studies.  相似文献   
94.
OBJECTIVES: We investigated the prevalence and characteristics of HIV-positive women who do not report highly active antiretroviral therapy (HAART) use. METHODS: We analyzed HAART use among 1165 HIV-positive participants in the Women's Interagency HIV Study. RESULTS: Between October 1, 2000, and March 31, 2001, 254 women with clinical indications for HAART reported not using it, 635 reported HAART use, and 276 had no clinical indications. In multivariate analysis, using crack/cocaine/heroin and a history of abuse decreased the likelihood of using HAART, whereas being White increased it. CONCLUSIONS: One of 4 women for whom HAART was indicated reported not using HAART. Childhood sexual abuse prevention, more intensive abuse treatment, and continuing drug treatment may enhance HIV disease treatment of women.  相似文献   
95.
96.
Is retinal photography useful in the measurement of stroke risk?   总被引:5,自引:0,他引:5  
Wong TY 《Lancet neurology》2004,3(3):179-183
BACKGROUND: The retinal microcirculation can be viewed non-invasively to give a unique perspective of the cerebral microcirculation in vivo. Studying pathological changes of retinal blood vessels (microaneurysms, retinal haemorrhages, and retinal arteriolar narrowing) may help to understand the causes of various cerebrovascular disorders. Retinal photography provides such an opportunity. RECENT DEVELOPMENTS: Several recent studies have shown that retinal microvascular changes are reliably documented by retinal photographs. These retinopathy changes seem to be fairly common in the general population, even in people without hypertension or diabetes. Retinopathy is related to incident clinical stroke and stroke mortality and to MRI-defined subclinical cerebral white-matter lesions and cerebral atrophy, independent of blood pressure, diabetes, and other cerebrovascular risk factors. WHERE NEXT?: Retinal microvascular abnormalities seem to be markers of concomitant cerebral microangiopathy, and retinal photography may be useful for the investigation of microvascular disorders of the brain in clinical and epidemiological settings. Future research should be aimed at the development of standardised photographic methods for the assessment of retinal microvascular changes, the replication of these findings in other populations and in people with other cerebrovascular disorders, and the examination of the increased accuracy of stoke-risk stratification given by retinal photography  相似文献   
97.
OBJECTIVE: To determine the endometrial safety of 2 years of treatment with lower doses of continuous combined conjugated equine estrogens (CEE) and medroxyprogesterone acetate (MPA). DESIGN: Randomized, double-blind, placebo-controlled, multicenter metabolic and osteoporosis substudy of the Women's Health, Osteoporosis, Progestin, Estrogen (Women's HOPE) study. SETTING: Nineteen study centers across the United States. PATIENT(S): Healthy, postmenopausal women (n = 822) with an intact uterus were recruited. INTERVENTION(S): Patients received CEE 0.625, CEE 0.625/MPA 2.5, CEE 0.45, CEE 0.45/MPA 2.5, CEE 0.45/MPA 1.5, CEE 0.3, CEE 0.3/MPA 1.5 (all doses mg/day), or placebo for 2 years. Endometrial biopsies were evaluated at baseline and years 0.5, 1, 1.5, and 2 using a centralized protocol. MAIN OUTCOME MEASURE(S): Efficacy of lower doses of CEE/MPA in reducing the incidence of endometrial hyperplasia rates associated with unopposed estrogen (E). RESULT(S): No cases of endometrial hyperplasia were seen in the four CEE/MPA groups. For the CEE-alone groups, a dose-related increase in incidence rates from 3.17% (CEE 0.3 mg) to 27.27% (CEE 0.625 mg) was seen at 2 years. The number of cases increased from year 1 to year 2. For the CEE-alone groups, the incidence rates and types of hyperplasia diagnosed varied among the pathologists. CONCLUSION(S): Two years of treatment with lower doses of CEE/MPA provided endometrial protection comparable to that seen with commonly prescribed doses. These regimens should be considered for postmenopausal women who are candidates for hormone therapy.  相似文献   
98.
Adherent cells are strongly influenced by the mechanical aspects of biomaterials, but little is known about the cellular effects of spatial variations in these properties. This work describes a novel method to produce polymeric cell culture surfaces containing micrometer-scale regions of variable stiffness. Substrates made of acrylamide or poly(dimethylsiloxane) were patterned with 100- or 10-microm resolution, respectively. Cells were cultured on fibronectin-coated acrylamide having Young's moduli of 34 kPa and 1.8 kPa, or fibronectin-coated PDMS having moduli of 2.5 MPa and 12 kPa. Over several days, NIH/3T3 cells and bovine pulmonary arterial endothelial cells accumulated preferentially on stiffer regions of substrates. The migration, not proliferation, of cells in response to mechanical patterning (mechanotaxis) was responsible for the accumulation of cells on stiffer regions. Differential remodeling of extracellular matrix protein on stiff versus compliant regions was observed by immunofluorescence staining, and may have been responsible for the observed mechanotaxis. These results suggest that mechanically patterned substrates might provide a general means to study mechanotaxis, and a new approach to patterning cells.  相似文献   
99.
Five known kaurane type diterpenoids, 16alphaH,17-isovaleryloxy-ent-kauran-19-oic acid (1), 16alpha-hydroxy-17-isovaleryloxy-ent-kauran-19-oic acid (2), paniculoside-IV (3), 16alpha-hydroxy-ent-kauran-19-oic acid (4), and ent-kaur-16-en-19-oic acid (5) were isolated from the root of Acanthopanax koreanum by repeated column chromatography and reversed phase preparative HPLC. The structures of these compounds were established from physicochemical and spectral data. Among the isolated compounds 16alphaH,17-isovaleryloxy-ent-kauran-19-oic acid (1) showed potent inhibitory activity (IC50 value, 16.2 uM) on TNF-alpha secretion from HMC-1, a trypsin-stimulated human leukemic mast cell line.  相似文献   
100.
Cisplatin (CDDP) resistance is one of the major impediments in cancer chemotherapy. In an attempt to define this complex mechanism(s) of resistance, we have identified 7 cDNA fragments which are overexpressed in CDDP resistant small cell lung cancer cell line (SR-2) using PCR selected cDNA subtraction. One of these fragments was identical with nucleotide 3657-4042 of MRP4. The other fragments share sequence homology with elongation factor alpha, human placenta villi cDNA, heat shock protein (Hsp70), ribosomal RNA, BNP1 brain specific Na-dependent inorganic phosphate cotransporter and telomeric catalytic subunit. Examination of other MRP members (MRP1, 2, 3, 5, 6) did not show discernable differences in their expression between the parental (SCLC1) and the CDDP-resistant variant (SR-2). Full length MRP4 cDNA was obtained from SCLC1 and SR-2. Both cell lines carry a point mutation at nucleotide 3532 while SR-2 carries two additional mutations at 3228 and 3246. Since MRP4 is known to transport azidiothymidine (AZT) and overexpression of MRP4 confers AZT resistance, we have studied growth inhibitory effects of AZT and [3H]-AZT accumulation. Interestingly, SR-2 is more sensitive to AZT while accumulating lesser amounts of [3H]-AZT. The thymidine kinase activity is similar in both cell lines. Thus, the increased sensitivity to AZT in SR-2 could not be solely due to mutation of MRP4. These findings are most likely due to the inhibitory effects of telomere catalytic subunit by AZT. Thus, certain biochemical changes induced by CDDP can be explored for future treatment to overcome this form of resistance.  相似文献   
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