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91.
This article studies the causes and treatment of benign nonpeptic esophageal strictures. The authors also discuss various therapeutic techniques for esophageal strictures, including esophageal dilatation with various dilators and balloons. Although the goals of stricture therapy are to relieve dysphagia and prevent stricture reoccurrence, only the first of these goals (effective dilatation with bougienage or balloon dilatation) has been achieved. The prevention of stricture reoccurrence remains to be achieved.  相似文献   
92.
Tea-tree oil (oil of Melaleuca alternifolia) has recently received much attention as a natural remedy for bacterial and fungal infections of the skin and mucosa. As with most naturally occurring agents, claims of effectiveness have been only anecdotal; however, several published studies have recently demonstrated tea-tree oil's antibacterial activity. This study was conducted to determine the activity of tea-tree oil against 58 clinical isolates: Candida albicans (n = 10), Trichophyton rubrum (n = 8), Trichophyton mentagrophytes (n = 9), Trichophyton tonsurans (n = 10), Aspergillus niger (n = 9), Penicillium species (n = 9), Epidermophyton floccosum (n = 2), and Microsporum gypsum (n = 1). Tea-tree oil showed inhibitory activity against all isolates tested except one strain of E floccosum. These in vitro results suggest that tea-tree oil may be useful in the treatment of yeast and fungal mucosal and skin infections.  相似文献   
93.
BACKGROUND: Mental disorders impose a multi-billion dollar burden on the economy each year; translating the burden into economic terms is important to facilitate formulating policies about the use of resources. METHODS: For direct costs, data were obtained from national household interview and provider surveys; for morbidity costs, a timing model was used that measures the lifetime effect on current income of individuals with mental disorders, taking into account the timing of onset and the duration of these disorders, based on regression analysis of Epidemiologic Catchment Area study data. RESULTS: The total economic costs of mental disorders amounted to US$147.8 billion in 1990. Anxiety disorders are the most costly, amounting to $46.6 billion, or 31.5% of the total; schizophrenic disorders accounted for $32.5 billion, affective disorders for $30.4 billion, and other mental disorders for $38.4 billion. CONCLUSIONS: Mental illnesses, especially anxiety disorders, are costly to society. Although anxiety disorders have a higher prevalence than affective disorders and schizophrenia, use of medical care services is lowest for anxiety disorders. Anxiety disorders appear to be under-recognised and untreated even though treatment interventions have been shown to be effective and can be delivered in a cost-efficient manner.  相似文献   
94.
Normal human peripheral blood mononuclear cells (MNCs), particularly T lymphocytes (T cells), are a rich source of granulocyte-macrophage colony-stimulating factor (GM-CSF). Glucocorticoids are known to inhibit GM-CSF production in in vitro cultures of a human fibroblast cell line and in normal human blood monocytes and alveolar macrophages. To determine whether glucocorticoids also inhibit GM-CSF production from normal human MNCs and T cells, we set up cultures of normal human MNCs and T cells in a liquid system in the presence and absence of 5, 50, and 250 microg/dL of hydrocortisone, and an hour later, a constant dose of 50-ng/mL Escherichia coli lipopolysaccharide (LPS) or 10-microg/mL phytohemagglutinin (PHA) was added. After three days, cell counts and GM-CSF levels were determined. Administering 50- and 250-microg/dL hydrocortisone decreased lymphocyte recovery from MNC cultures with LPS (p < or = 0.01), and 250 microg/dL of hydrocortisone decreased lymphocyte recovery from MNC and T-cell cultures with PHA (p < or = 0.03). The amount of GM-CSF produced from PHA-stimulated MNCs was about 100-fold higher than that produced from LPS-stimulated MNCs. The magnitude of GM-CSFs produced in MNC and T-cell cultures stimulated by PHA was comparable (p=0.88). Administering hydrocortisone at 5, 50, and 250 pg/dL decreased GM-CSF production (p < 0.003) in LPS- or PHA-stimulated MNC cultures and in PHA-stimulated T-cell cultures. PHA (not tested with LPS)-stimulated GM-CSF messenger RNA (mRNA) expression was blocked by hydrocortisone. These results indicate that lower concentrations of hydrocortisone inhibit GM-CSF production from normal human blood MNCs and T cells entirely by inhibiting the expression of GM-CSF mRNA, and higher concentrations of hydrocortisone inhibit by a combined effect of inhibiting the expression of GM-CSF mRNA and decreasing the lymphocyte count.  相似文献   
95.
Decades of practice and research suggest that nurse practitioners (NPs) provide cost-effective and high-quality care. Managed care's emphasis on prevention and cost savings led some policy makers to view NPs as a way to meet the need for primary care providers. However, access to and utilization of NPs has increasingly been controlled by managed care organizations (MCOs) through their selection of providers for primary care panels. This study employed qualitative methodology to examine NPs' experiences with MCOs. Three focus groups, comprising 27 NPs in New York and Connecticut, revealed NPs' mixed reactions to managed care and a range of sentiments regarding NPs' efforts to be listed as primary care providers. The results reflected NPs' concerns about their perceived "invisibility," as well as their sense of "invincibility" in the ways in which NPs are responding to the barriers posed by MCOs. They identified barriers to, as well as ways to facilitate, being listed by MCOs, and described the importance of NPs working individually and collectively in negotiating with MCOs.  相似文献   
96.
Magnetic resonance spectroscopy (MRS), an application of the methods of nuclear magnetic resonance (NMR), is a functional imaging modality that provides a view of localized biochemistry in vivo. A number of studies applying MRS to the neurochemistry of schizophrenia have been reported, which encompass a range of patient populations, states of medication, anatomic regions, nuclear species, and MRS techniques. A brief review of the history and methodology of NMR and MRS is presented. Comparison is made of MRS capabilities with other functional imaging modalities. Aspects of the neurochemistry of schizophrenia relevant to MRS studies are reviewed, as are the reported MRS studies involving patients with schizophrenia. Areas of consistent findings include decreased phosphomonoesters and increased phosphodiesters in frontal lobes, and decreases in the putative neuronal cell marker, N-acetylaspartate, in temporal lobes. Studies of neurotransmitters such as glutamate, gamma-aminobutyric acid, and glutamine have generated inconsistent results. New insights into alterations in neurochemistry in schizophrenia have been provided by MRS. Studies of neurotransmitters have future potential with improvements in field strength and in spectral editing techniques. MRS has the potential to measure brain medication levels and simultaneous effects on neurochemistry. MRS may assist in characterizing high-risk populations, and ultimately guide medication use.  相似文献   
97.
98.
A nurse-driven clinic that uses a client-centered approach evolved from an independent ambulatory care program. The clinic operates 4 to 5 hours per day and provides patient counseling, health care maintenance, primary care, patient education, and therapeutic care.  相似文献   
99.
The Colles' fracture is probably the most common fracture seen in the Emergency Department. Although there are several different methods of reduction and fixation, the goal of any treatment plan is to return the patient to normal function. Depending on the complexity, the Colles' fracture can be successfully treated open or closed. This article reviews the mechanism of injury, assessment, conservative or operative treatment, and rehabilitation of these fractures.  相似文献   
100.
BACKGROUND: Investigations concerning the severity of respiratory syncytial virus (RSV) disease as related to (1) RSV type and genotype determined respectively by PCR and restriction enzyme analysis and (2) interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) values in samples of nasopharyngeal secretion (NPS) have not been previously reported. METHODS: We prospectively studied 105 RSV infections in the lower respiratory tract of infants and young children admitted to a pediatric department in Copenhagen during three winter seasons, 1993, 1994 and 1995. RSV strains were typed and genotyped, respectively, by PCR and nucleic acid restriction analysis and correlated to the severity of the disease. The ratio IL-6:TNF-alpha, determined from IL-6- and TNF-alpha values in samples of NPS, was related to the severity of the disease. Concentrations of IL-6 and of TNF-alpha were determined in serum samples taken during 5 weeks after the onset of illness. RESULTS: Type B infections produced more severe disease than did type A infections, as assessed on the length of the hospital stay, use of respiratory support and the presence of an infiltrate on a chest radiograph. This difference was age-related. It was observed in infants 0 to 5 months old, but not in older age groups. Type B genotype B1122 produced more severe disease than type A genotype A2311 in infants 0 to 11 months old. Increased serum concentrations of IL-6 and TNF-alpha were detected in samples taken 1 to 2 days after the onset of illness. Whereas TNF-alpha serum concentrations remained high, IL-6 serum concentrations decreased during the following 3 to 4 weeks. The IL-6:TNF-alpha ratio in samples of NPS was related to the severity of the disease. A high ratio was related to a low severity. CONCLUSIONS: The severity of disease in patients admitted with acute RSV infections can be correlated to the RSV type as determined by PCR, to the RSV genotype as determined by nucleic acid restriction analysis and to the ratio IL-6:TNF-alpha in NPS.  相似文献   
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