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81.
Contact urticaria from protein hydrolysates in hair conditioners   总被引:1,自引:0,他引:1  
Protein hydrolysates (PHs) are added to hair-care products (to "repair" broken hair), soaps, bath gels, creams, etc. From one to 22 PHs used in hair-care products (collagen, keratin, elastin, milk, wheat, almond, and silk) were tested in three patient groups: A) 11 hairdressers with hand dermatitis B) 2160 consecutive adults with suspected allergic respiratory disease subjected to routine skin prick tests C) 28 adults with atopic dermatitis.
In group A, all the 22 PHs were tested with scratch and patch tests. In groups B and C, one to three PHs were tested with prick tests. Positive scratch/prick test reactions were seen in 12 patients from three PHs altogether. All were women with atopic dermatitis, and all reacted to at least hydroxypropyl trimonium hydroly:ed collagen (Crotein Q"). In three patients, prick and open tests with a hair conditioner containing Crotein Q were performed with positive results. One patient reported contact urticaria on her hands, and two reported acute urticaria on their head, face, and upper body from a hair conditioner containing Crotein Q. In seven of the eight studied sera, specific IgE to Crotein Q was detected. In conclusion, PHs of hair cosmetics can cause contact urticaria, especially in patients with atopic dermatitis.  相似文献   
82.
Abstract Over the past 15–20 years, research has progressively focused on the mucosal T cell as the central factor in the initiation of physiological or pathological changes, first in the growth and maturation of the early (postnatal) intestine, and second in adult-type enteropathies resulting from sensitivity to either food or pathogen-derived antigens. T cell-mediated events may be measured, for example, in terms of specific immunopathologic patterns of change and injury, such as type 1 (lymphocyte infiltration), type 2 (crypt hyperplasia) and type 3 (flat-destructive), which can be recognized and quantitated microscopically; by determination of lymphocyte reactivity through secretion of interleukin-2 receptors (IL-2R) into plasma or expression by mucosal lymphocytes; by quantitation of lymphocyte subsets emigrating into inflamed tissues by immunoperoxidase-labelled monoclonal antibodies; or by the determination of T cell receptor polymorphisms. Alterations in intestinal growth, structure and function at weaning are likely to be T cell-mediated as they are analogous to the same type 1/2 lesions that reflect modulation of adult mucosal architecture in food and parasite-induced hypersensitivity reactions. Enteropathies associated with HIV infection and T cell deficiency display a milder degree of villous flattening and impaired crypt hyperplasia than that typical of gluten-sensitivity, suggesting a reversion to lesser degrees of mucosal pathology (type 1/2). Clearly more information will accrue; meanwhile the remarks in this brief survey should provide a firm basis whereby clinician and scientist can meet, and together recognize and further dissect the modulatory effect of T lymphocytes on mucosal structure and function.  相似文献   
83.
Hyperparathyroidism is associated with impaired glucose tolerance, and parathyroidectomy may improve carbohydrate homeostasis. It has been suggested that parathyroid hormone (PTH) suppresses insulin secretion but it is unclear whether it also interferes with the peripheral action of insulin. To evaluate in vivo effects of PTH on insulinmediated glucose utilization, 15 male Sprague Dawley rats were continuously infused with rat PTH (1–34) using an Alzet miniosmotic pump at a rate of 0.03 nm/hour. Controls were infused with the vehicle alone. Following 5 days of PTH infusion, plasma calcium (Ca) levels were higher in the PTH-infused rats (12.3±0.2 versus 9.9±0.1 mg/dl, P<0.01). On the 5th day, glucose (700 mg/kg) and insulin (0.175 U/kg) were given as a bolus infusion through the left femoral vein, blood samples were obtained from the right femoral vein, and plasma glucose and insulin were measured at basal (0 minutes) and at 2, 5, 10, and 20 minutes postinfusion. Basal, nonfasting glucose levels were higher (166±4 versus 155±4 mg/dL, P<0.04) in the PTH-infused rats but their insulin levels were similar to those of controls (6.5±0.6 versus 5.6 ±0.5 ng/ml). Postinfusions and maximal (2 minutes) glucose and insulin levels were similar in both groups. However, although insulin levels were similar in both groups at all measured time points, glucose levels at 20 minutes were higher in the PTH-treated rats (205±13 versus 173±9; P<0.03). Also, calculated glucose disappearance rates (Kg) were decreased in the PTH-infused rats (4.05±0.3 versus 4.63±0.8; P=0.054), suggesting an impaired peripheral effect of insulin on glucose utilization. To gain insight into the potential contribution of the hypercalcemia or the PTH to these abnormalities, correlation evaluations were performed. Only in PTH-infused rats did plasma Ca correlate with plasma glucose at 0 and 20 minutes (r=0.6, P=0.02; r=0.7, P=0.01) and with the area under the glucose curve (r=0.6, P=0.03) during the glucose-insulin infusion. Also only in PTH-infused rats did PTH correlate with 0 (P=0.07) and 20-minute (P=0.02) plasma glucose levels. There was no correlation between either Ca or PTH and basal insulin levels or the area under the insulin curve in either group. Consequently, we suggest that in the rat, PTH infusion associated with hypercalcemia impairs insulin effect on glucose utilization in vivo and this defect may be induced by the Ca, PTH, or both.This study was presented in part at the 76th Annual Meeting of the Endocrine Society, Anaheim, CA, USA, June 1994.  相似文献   
84.
The ability of sperm to swell in hypo-osmotic conditions was examined in 211 semen samples from the partners of patients about to undergo oocyte retrieval for in-vitro fertilization (IVF). The test was performed using aliquots of semen, the remainder of which was then prepared for IVF. No significant difference was found, in either the percentage of swollen sperm or the type of swelling response, between samples that achieved fertilization in vitro and those that did not, or between any of the diagnostic categories of infertility (tubal damage, unexplained infertility, oligospermia). In samples which achieved fertilization in vitro there were correlations between sperm swelling and sperm motility (r = -0.51) and abnormal morphology (r = 0.33), but no such correlations were demonstrated in samples that failed to achieve fertilization. Moreover, there was no significant difference between the percentage of swollen sperm in semen (mean motility 64%), in samples immediately after preparation for IVF (mean motility 96%) or in capacitated sperm 24 h after preparation (mean motility 91%). These results demonstrate that the hypo-osmotic sperm swelling test does not assist in the prediction of the fertilizing capacity of human sperm in vitro.  相似文献   
85.
Mingying  Lai  Ningli  Wang 《眼科学报》1997,13(3):116-119
Purpose : To compare the clinical application value of Ultrasound biomicrsocpic dark room provocative test with the traditional dark room test in screening primary angle closure glaucoma (PACG).Methods: 22 eyes with PACG in prodromal stage and 30 eyes with deep anterior chamber and wide angle of 15 normal persons were observed in this trail. All 52 eyes were performed traditional dark room provocative test and ultrasound biomicorosopic darkroom test respectively. With different positive diagnostic criteria, the sensitivity of the two methods were compared using chi-squared analysis.Results : After staying in the dark room for 2 hours, In case group, IOP in 10 of 22 eyes rose more than 1. 07kPa(1kPa = 7.5mmHg), in 12 eyes less than 1.07kPa or had no changes; appositional angle closure were found by Goldmann gonioscopy in 8 eyes : 3 eyes in two quadrants, 5 eyes in more than two quadrants; the appositional angle closure was found by UBM in 15 eyes; 3 eyes in one quadrants, 5 eyes in two quadrants, 7 eyes  相似文献   
86.
Study of the dynamics of cardiac output in rats with different tolerance to acute massive blood loss showed that the pumping ability of the heart remains intact during the entire posthemorrhagic period in all high-resistant and in 65% low-resistant rats. In 35% rats that were low-resistant to blood loss, the cardiac output deficiency syndrome developed after cessation of bleeding against the background fall in arterial pressure and a decrease in the hepatic blood flow, which are the signs of rapid variant of the dysfunction produced by acute blood loss. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 10, pp. 384–388, October, 1998  相似文献   
87.
PROBLEM: There is substantial data that support the efficacy of paternal leukocyte immunization (PLI) for the treatment of alloimmune mediated miscarriage; however, there is confusion regarding the laboratory test that should be performed to determine levels of maternal anti-paternal leukocyte antibodies (MAPLA). METHOD: Popular methodologies employed include: 1) microcytotoxicity (MCX), 2) mixed lymphocyte culture (MLC), and 3) cell flow cytometry crossmatch (FCXM). Cell flow cytometry crossmatch correlates well with the more difficult MLC assay although the former proves the more sensitive study. This work compares the MCX assays with FCXM. The study group consisted of ten women who had a history of three or more spontaneous abortions (SABs). All ten had very low levels (<10%) of MAPLA as measured by FCXM. Following PLI all subjects demonstrated elevated levels (>50%) of MAPLA by FCXM. At 12 weeks gestation, sera were simultaneously measured for MAPLA by MCX and FCXM. RESULTS: Although all ten patients had very high levels of MAPLA by FCXM during pregnancy, five of ten had antibodies to HLA Class I and two of ten had antibodies to HLA Class II paternal antigens by MCX. Furthermore, all patients who were positive by MCX to paternal Class I antigens were also positive to Class I antigens not seen in either parent. Both patients who were positive by MCX to paternal Class II antigens were also positive to maternal Class II antigens. Notable is that all ten women eventually delivered healthy infants. CONCLUSION: Based on this preliminary study, the MCX assay is neither sensitive or reliable enough to determine the need and/or to monitor the effectiveness of PLI. Flow cytometry should be the modality of choice when determining the need for alloimmunotherapy and to monitor the effectiveness of treatment.  相似文献   
88.
When administered systemically, glucose attenuates deficits in memory produced by several classes of drugs, including cholinergic antagonists and opiate agonists. Glucose also enhances memory in aged rats, mice, and humans. In addition, glucose ameliorates age-related reductions in paradoxical sleep. Because deficits in paradoxical sleep are most marked in those individual aged rats that also have deficits in memory, treatments which improve one of these functions may similarly improve the other. The present experiments show that glucose attenuates deficits in paradoxical sleep and memory after atropine administration, with similar dose-response curves for both actions. In the first experiment, rats received saline, atropine (1 mg/kg), glucose (100 mg/kg) or combinations of atropine + glucose (10, 100, 250, and 500 mg/kg) 30 min before assessment on a spontaneous alternation task. In the second experiment, 3-h EEGs were assessed for spontaneous daytime sleep in rats administered saline, atropine (1 mg/kg), glucose (100 mg/kg) or combinations of atropine + glucose (10, 100 and 250 mg/kg). In both experiments, glucose significantly attenuated deficits at an optimal dose of 100 mg/kg. A third experiment assessed blood glucose levels after injections of atropine + glucose (100 mg/kg) and determined that blood glucose levels were similar to those produced by other treatments which enhance memory. These results are consistent with the view that paradoxical sleep and at least one test of memory are similarly influenced by atropine and glucose.  相似文献   
89.
A critical commentary and updating of the guinea pig maximization test   总被引:4,自引:3,他引:1  
The guinea pig maximization test (GPMT) of Magnusson and Kligman was published in 1969. Since then, a vast body of practical experience with the test has been accumulated. New information requires that certain aspects of the procedure be reevaluated, especially with regard to the interpretation of challenge results. In particular, awareness of the phenomenon of hyperirritable skin (the 'angry back' phenomenon) suggests that presently used controls are not always adequate and may overstate allergenicity owing to false-positive reactions. The control group should be exposed to a chemical insult at induction which provokes an inflammatory reaction comparable to the test substance. We present strategies to distinguish irritant from allergic responses. Allergic reactions should persist on rechallenge weeks later, while nonspecific irritant reactions generally fade and are irreproducible in particular animals. Finally, when a chemical is identified as a contact sensitizer of risk is necessary to estimate the relevance of the test result to usage in the real world.  相似文献   
90.
恒河猴坐姿着陆冲击内耳损伤的观察   总被引:2,自引:0,他引:2  
为研究机体及各组织器官对冲击力的耐受限值,探讨致伤原因及提出防护措施,利用着陆冲击塔,使实验动物恒河猴的坐姿状态下,进行冲击试验,试验后1h左右处死,作大体解剖观察并取心,肝,脾,肺,颞骨等组织,固定,切片,镜检。同时重点观察了内耳的损伤。结果表明,冲击载荷不大(平台过载值为≤25G)时内脏虽然有轻度损伤,但内耳可避免受员,当冲击力加大到一定程度(平台过载值为30~35G)导致内脏中等损伤时,内耳  相似文献   
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