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991.
Understanding the reasons for infertility and the development of new techniques for its treatment is one of the fields within medicine which has undergone a dramatic development during the last two decades. In the past, gynecologists seemed more successful in the treatment of female problems than urologists and andrologists on the male side, while in the last couple of years this scenario has changed due to the development of both operative procedures to harvest spermatozoa from the epididymis and the testis and the ability to micro-inject single spermatozoa (ICSI) or even spermatides directly into metaphase II oocytes. It should, however, be emphasized that the successful development of in vitro fertilization (IVF) and other assisted reproduction technologies (ART), could not have taken place without the development of diagnostic innovations, such as immunoassays of hormones, high resolution ultrasound and various endoscopic techniques. Today, treatment of the infertile couple is less of a medico-technical problem and more a socio-economic dilemma. This communication is an attempt to summarize the more prominent steps in reproductive medicine during the last decades and one more general conclusion of global relevance which can be drawn, is that less money must be spent on diagnosis and more resources transferred to treatment options.  相似文献   
992.
The aim of this study was to assess the translational value of the quantitative assay of mutant p53 protein expression as both a prognostic indicator and a tool to determine appropriate therapy in a group of relatively innocuous and morphologically similar soft tissue sarcomas (STSs). Using a quantitative ELISA, we analyzed mutant p53 protein expression in 47 well-differentiated (grade I) STSs from patients treated in our Department of Surgical Oncology. Sixteen of 47 tumors expressed up to 42.6 ng mutant p53 protein/mg total protein. After a mean follow-up of 112 months, 63% of the patients with mutant p53+ tumors but only 16% of the patients with mutant p53- tumors had died (P < 0.01). Mutant p53 expression of >/=4.5 ng predicted even greater reduction in survival. These data show that mutant p53 expression identifies biologically aggressive grade I STSs. This molecular marker should have translational value as a tool to select those patients likely to benefit from aggressive multimodal therapy and intense surveillance.  相似文献   
993.
The paper is concerned with two unit cold standby systems having one regular repairman and one expert repairman. The expert is called only if the regular repairman is not able to complete the repair within some toletable (patience) time. In model 1, it is assumed that an expert, on his arrival, gives instructions to the regular repairman for completing the repair, in model 2, it is assumed that the expert himselg takes over the system and the regular repairman leaves the repair in the presence of the expert. In model 3, there is no provision of calling the expert. Techniques of the semi-Markov processes and regenerative processes are used to obtain various measures of system effectiveness and profit incurred. A pairwise comparison of model 1 is made with model 2 and model 3 through graphs.  相似文献   
994.
OBJECTIVE: To study the trends of paralytic poliomyelitis in pre Pulse Polio Immunization period. SETTING: Hospital based sentinel surveillance. METHODS: Analysis of 6704 line-listed poliomyelitis cases from January 1989 to December 1994 attending the Department of Physical Medicine and Rehabilitation. RESULTS: 85% of all cases reported in Delhi were from this center. A decline in alternate year peaks was observed from 1621 cases in 1990 to 1062 cases in 1994. There was an increase in proportion of cases with poliomyelitis in fully vaccinated children from 14% to 22.9%. Polio type I virus was the commonest isolated virus in all the years except 1993, when type II was isolated in 38.7% of cases. CONCLUSION: Despite improvement in immunization coverage, the study reveals that a large number of children (67.2%) who suffer from poliomyelitis are unvaccinated. This stresses need to intensify and sustain high level of immunization coverage with effective vaccine.  相似文献   
995.
996.
State-dependent changes in upper airway caliber were studied with magnetic resonance imaging (MRI) techniques. We hypothesized that changes in airway caliber during sleep in normal subjects would result from positional and dimensional changes in upper airway soft-tissue structures, including the lateral pharyngeal walls, tongue, and soft palate. We used MRI to study 15 normal subjects during wakefulness and sleep. Sleep was facilitated by one night of sleep deprivation prior to MRI. During sleep, the volume of the retropalatal (RP) airway was reduced by 19% (p = 0.03). The volume of the retroglossal (RG) airway was not significantly reduced during sleep, suggesting that the RP region may be more likely to collapse. The mean minimal cross-sectional airway area was reduced by 228% (p = 0.004) in the RP and by 22% (p = 0.02) in the RG region during sleep as compared with values in anatomically matched axial images during wakefulness. Airway anteroposterior (AP) and lateral dimensions were also significantly reduced in the RP region. Airway narrowing in the RP region was associated with a 7% increase in thickness of the lateral pharyngeal walls (p = 0.04). In nine subjects, sagittal data showed significant posterior displacement of the soft palate during sleep as compared with wakefulness. Multiple linear regression analyses indicated that reduction in the RP airway area during sleep resulted from posterior movement of the soft palate, thickening of the lateral pharyngeal walls, and an increase in tongue oblique distance. We conclude that the lateral pharyngeal walls play an important role in upper airway narrowing during sleep in normal subjects.  相似文献   
997.
Abnormalities of phospholipids in hypertension have previously been described in human erythrocyte, platelet, and plasma lipoproteins. Since the heart and kidney are adversely affected by hypertension, we investigated possible alterations in their membrane phospholipids, which could play a role in the derangement of intracellular ion balance widely observed in hypertension. The phospholipid compositions of heart and kidney from spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats were determined by using 31P nuclear magnetic resonance (NMR) spectroscopy. Absolute contents of all phospholipids in hypertensive hearts and kidneys were significantly higher than in normotensive hearts and kidneys. Expressed as a fraction of total phospholipid, cardiolipin (CL) and phosphatidylethanolamine plasmalogen (PEp) were significantly increased in SHR hearts compared to WKY hearts (CL and PEp were 7.95+/-0.22% and 13.16+/-0.35% in SHR vs. 7.01+/-0.20% and 11.19+/-0.42% in WKY rats, P< or =0.05), but phosphatidylethanolamine (PE) and phosphatidylcholine (PC) were significantly decreased in SHR (PE and PC were 22.46+/-0.37% and 44.81+/-0.43% in SHR vs. 24.02+/-0.44% and 46.01+/-0.50% in WKY rats, P< or =0.05). In the phospholipids extracted from rat kidneys, the percentage of PE was significantly higher for SHR than for WKY rats (20.37+/-0.60% vs. 18.43+/-0.37%, P< or =0.05), while PEp and phosphatidylserine (PS) were significantly lower for SHR (PEp and PS were 10.22+/-0.36% and 8.42+/-0.28% in SHRs vs. 11.29+/-0.36% and 9.71+/-0.40% in WKY rats, P< or =0.05). The above alterations in phospholipid composition might contribute to the higher oxygen consumption in the hypertensive heart and abnormal intracellular ion concentrations and ion transport in the heart and the kidney in hypertension.  相似文献   
998.
The demand for health care and social welfare services for the elderly has increased and in Japan, there is a need in the social system to improve the quality of life, especially for those who are disabled. This article directs attention to bed-ridden elderly persons from the standpoint of social problems attending economic development and population changes based on data from Japan, the United States, Sweden, and OECD countries. Compared to the United States, there are more bed-ridden elderly in Japan, and inadequate public resources for caring. Physicians, nurses, care workers, and rehabilitation specialists such as physiotherapist and occupational therapist per 1000 aged sixty-five or over are 89.5 in Japan while 237.4 in Sweden. Japan has the fewest such health and welfare personnel among developed countries. Even with increases in such personnel through the New Gold Plan, future increase in aged population would off-set the effect and the problem of providing care for the elderly remains.  相似文献   
999.
OBJECTIVE: To examine the temporal integration of vascular endothelial growth factor (VEGF), which has been shown to be present in wound fluid, with the putatively related processes of wound fluid oxygen content, wound angiogenesis, and granulation tissue formation. SUMMARY BACKGROUND DATA: During cutaneous wound repair, new tissue formation starts with reepithelialization and is followed by granulation tissue formation, including neutrophil and macrophage accumulation, fibroblast ingrowth, matrix deposition, and angiogenesis. Because angiogenesis and increased vascular permeability are characteristic features of wound healing, VEGF may play an important role in tissue repair. METHODS: A ventral hernia, surgically created in the abdominal wall of female swine, was repaired using silicone sheeting and skin closure. Over time, a fluid-filled wound compartment formed, bounded by subcutaneous tissue and omentum. Ultrasonography was performed serially to examine the anatomy and dimensions of the subcutaneous tissue and wound compartment. Serial wound fluid samples, obtained by percutaneous aspiration, were analyzed for PO2, PCO2, pH, and growth factor concentrations. RESULTS: Three independent assays demonstrate that VEGF protein is present at substantially elevated levels in a wound fluid associated with the formation of abdominal granulation tissue. However, the wound fluid is not hypoxic at any time. Serial sampling reveals that transforming growth factor beta-1 protein appears in the wound fluid before VEGF. CONCLUSIONS: The results suggest that VEGF is a prominent regulator of wound angiogenesis and vessel permeability. A factor other than hypoxia, perhaps the earlier appearance of another growth factor, transforming growth factor beta-1, may positively regulate VEGF appearance in the wound fluid.  相似文献   
1000.
Liquid crystals (LCs) were used to amplify and transduce receptor-mediated binding of proteins at surfaces into optical outputs. Spontaneously organized surfaces were designed so that protein molecules, upon binding to ligands hosted on these surfaces, triggered changes in the orientations of 1- to 20-micrometer-thick films of supported LCs, thus corresponding to a reorientation of approximately 10(5) to 10(6) mesogens per protein. Binding-induced changes in the intensity of light transmitted through the LC were easily seen with the naked eye and could be further amplified by using surfaces designed so that protein-ligand recognition causes twisted nematic LCs to untwist. This approach to the detection of ligand-receptor binding does not require labeling of the analyte, does not require the use of electroanalytical apparatus, provides a spatial resolution of micrometers, and is sufficiently simple that it may find use in biochemical assays and imaging of spatially resolved chemical libraries.  相似文献   
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