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排序方式: 共有473条查询结果,搜索用时 15 毫秒
1.
W Ertel M H Morrison A Ayala I H Chaudry 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(1):70-5; discussion 75-6
Hemorrhagic shock causes a severe suppression of cellular immunity and an increased susceptibility to sepsis that may be due to increased release of prostaglandin E2 by macrophages. Since chloroquine inhibits the secretion of prostaglandin E2 by macrophages in vitro, the effects of chloroquine administration in vivo following hemorrhagic shock on macrophage prostaglandin E2 secretion and on depressed cellular immunity were examined. Inbred C3H/HeN male mice, aged 6 to 8 weeks, were bled to a mean blood pressure of 35 mm Hg, which was maintained for 60 minutes, and adequately, resuscitated. Mice then received intramuscular injections of either saline (vehicle) or chloroquine (10 mg/kg of body weight). Prostaglandin E2 in macrophage supernatants (radioimmunoassay) concanavalin A-dependent splenocyte proliferation, and interleukin 2 in splenocyte supernatants (CTLL 20 interleukin 2-dependent proliferation) were determined 2 or 24 hours later. Hemorrhage caused a significant decrease of splenocyte proliferation (47%) and interleukin 2 release (49%) at 24 hours, while prostaglandin E2 secretion from macrophages was elevated at 2 hours. Chloroquine treatment attenuated depression of splenocyte functions and reduced prostaglandin E2 release. Furthermore, chloroquine treatment decreased the mortality of septic mice after hemorrhage to levels comparable with those of sham-operated mice. Thus, chloroquine may be a useful adjunct in the clinical setting for the treatment of shock-induced immunodepression and increased susceptibility to sepsis following hemorrhage. 相似文献
2.
Depressed antigen presentation function and membrane interleukin-1 activity of peritoneal macrophages after laparotomy 总被引:5,自引:0,他引:5
Although major tissue trauma produces profound depression of cell-mediated immunity, it is not known whether surgical trauma (i.e., midline laparotomy) has any adverse effect on the antigen presentation function and membrane interleukin-1 (IL-1) activity of peritoneal macrophages. To study this, C3H/HEJ (endotoxin-tolerant) mice were anesthetized. An approximately 1-inch midline abdominal incision was made, followed by abdominal closure. On days 1, 3, 5, and 7, peritoneal macrophages were harvested by means of peritoneal lavage, and antigen presentation capability was tested by incubating various numbers of peritoneal macrophages with 2 X 10(4) D10.G4.1 cells per well in the presence of conalbumin (400 micrograms/ml). The T helper cell clone (D.10.G4.1) proliferates on recognition of conalbumin in the context of Iak and also proliferates in the presence of membrane-bound IL-1 plus concanavalin A. To measure membrane IL-1 expression in peritoneal macrophages, Concanavalin A (10 micrograms/ml) was substituted for conalbumin. Cultures were incubated for 72 hours, pulsed with tritiated thymidine, and harvested. Peritoneal macrophages from laparotomized mice induced significantly less T helper cell proliferation on days 1 and 3 in the antigen presentation assay (37% and 30%, respectively; p less than 0.05) and in the membrane IL-1 assay (14% and 10%, respectively; p less than 0.05) as compared with the control. This difference was not detectable on day 5. More effective antigen presentation capability (167% of control; p less than 0.05) was seen on day 7. Thus laparotomy by itself produces marked depression of both antigen presentation function and membrane IL-1 activity of peritoneal macrophages, which may enhance susceptibility to intra-abdominal sepsis. 相似文献
3.
Background: This study was conducted to investigate grading performance when estimating the severity of static versus dynamic images of contact lens‐related ocular pathology. Methods: Thirty‐eight subjects used the Efron Grading Scales for Contact Lens Complications to grade the severity of ocular pathological changes depicted in static and dynamic (movie clip) computer‐displayed images of each of the following contact lens complications: bulbar conjunctival redness, limbal redness, papillary conjunctivitis, corneal staining, corneal infiltrates and meibomian gland dysfunction. The viewing of static and dynamic images was separated by seven weeks. Results: Grades assigned to dynamic images were 0.6 and 0.7 grading scale units higher than those assigned to static images for limbal redness and papillary conjunctivitis, respectively (p < 0.0001 for both). No difference was observed for the other four complications. There was an apparent trend for grading variability to be reduced (that is, observers grading in closer agreement) when grading dynamic versus static images. Conclusions: Absolute grades based on an assessment of signs of pathology represented in static images may, in some instances, underestimate the true severity of the condition. 相似文献
4.
J M Harkema M W Gorman L L Bieber I H Chaudry 《Archives of surgery (Chicago, Ill. : 1960)》1988,123(11):1415-1419
To study the effects of bacteremia on skeletal muscle leucine (LEU) metabolism, mongrel dogs were infused with normal saline or Escherichia coli (10(9)/kg). After a bolus dose (3.6 microCi), L(1-carbon 14) LEU (0.3 microCi/min) was infused directly into the isolated, constant-flow, in vivo gracilis muscle. Arteriovenous differences for amino acids, labeled and unlabeled LEU and alpha-ketoisocaproic acid (KIC), and labeled carbon dioxide were measured at ten-minute intervals for one hour. Bacteremia increased the net release of amino acids and total N2 from muscle. Moreover, plasma LEU that was deaminated and released as KIC was increased, and there was also an increase in decarboxylated plasma LEU during bacteremia. Despite the marked increase in KIC release from skeletal muscle during bacteremia, arterial concentrations were not significantly different from those of controls. An unchanged arterial plasma KIC concentration associated with a marked increase in KIC released from skeletal muscle indicates an increase in LEU metabolism, most likely in the liver. Thus, the increased skeletal muscle catabolism is not a futile cycle but rather an essential event to meet the increased metabolic needs of the body during bacteremia. 相似文献
5.
6.
Increased inducible apoptosis in CD4+ T lymphocytes during polymicrobial sepsis is mediated by Fas ligand and not endotoxin 总被引:10,自引:0,他引:10
Recent studies suggest that increased lymphocyte apoptosis (Ao) detected in peripheral blood T cells from burn patients appears to contribute to decreased lymphocyte immunoresponsiveness. However, while it is known that sepsis induces a marked depression in the splenocyte immune response (i.e. decreased interleukin-2, interferon-gamma production and proliferation) in response to the T-cell mitogen concanavalin A (Con A), it is unknown whether this depression is associated with an increase in inducible Ao and if so, which mediators control this process. To assess this, splenocytes were harvested from mice at 24 hr (a period associated with decreased Con A response) after the onset of polymicrobial sepsis [caecal ligation and puncture (CLP)] or sham-CLP (Sham) and then stimulated with 2.5 microg Con A/ml (24 hr). Septic mouse splenocytes stimulated with Con A, while not showing a change in their phenotypic make-up, did exhibit a marked increase in the percentage of splenocyte that were Ao+ which was associated with altered cytokine release. This appears to be due to an increase in the percentage of Ao+ cells in the CD4+ CD8- population and was associated with enhanced Fas antigen expression as well as an increase in mRNA for the Fas-FasL gene family. To determine if the changes in Ao are due to either endotoxin (a product of Gram-negative bacteria seen in CLP mice) or the expression of Fas ligand (FasL; a mediator of activation-induced lymphocyte Ao), a second set of studies examining Con A-inducible Ao was performed with splenocytes harvested from septic endotoxin-tolerant C3H/HeJ and the FasL-deficient C3H/HeJ-Fasl gld mice. The results show that increased splenocyte Ao detected following CLP is due to a FasL-mediated process and not to endotoxin. Thus the inadvertent up-regulation of FasL-mediated splenocyte Ao may contribute to the depression of splenocyte immune responses seen during polymicrobial sepsis. 相似文献
7.
Time course of hypo-osmotic swellings of human spermatozoa: evidence of ordered transition between swelling subtypes 总被引:2,自引:1,他引:2
Hossain AM; Rizk B; Barik S; Huff C; Thorneycroft IH 《Human reproduction (Oxford, England)》1998,13(6):1578-1583
The hypo-osmotic swelling test (HOST or HOS test) usually takes into
consideration the total HOS response value with no emphasis either on the
value of the response subtypes or the response evaluation time. This study
investigated the time course of HOS responses and analysed their
physiological relevance. Raw semen spermatozoa and Percoll washed
spermatozoa were used in the experiment. The morphological changes in the
sperm tail were monitored by incubating the spermatozoa in the hypo-
osmotic solution for 16 different time periods. The HOS reactive
spermatozoa and the type of HOS reaction (swelling subtypes) of the samples
subjected to different duration of treatment were identified under a phase
contrast microscope. Also the fate of individual spermatozoa in a
hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed
to a hypo-osmotic solution, the motility lasted usually less than 2 min and
motility characteristics were uniquely different from that of the
spermatozoa under iso-osmotic conditions. The HOS response development was
permanent but the motility loss due to hypo-osmotic shock was reversible up
to 1 min of incubation. There was an indication of ordered transition among
the HOS swelling subtypes apparently initiating with subtype b destined to
c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and
increase, respectively, while subtype b showed abrupt initial increase and
then gradual decrease. Transition from b to g could be direct or via one or
more than one subtypes. Ultrastructure based analysis indicated that HOS
response subtypes are the apparent reflection of the differences in the
cytoskeletal assembly of the sperm tail and thus may be identifying
different physiological variants in the sperm population. These results
indicate that shorter incubation is essential to document the kinetics of
various HOS responses but the conventional HOS test misses these important
HOS features because of lengthy incubation. Since the time course of
ordered transition of HOS responses will vary more than the total HOS
response in semen of different aetiologies, the importance of HOS response
subtypes and response evaluation time should be taken into consideration
when applying HOS test.
相似文献
8.
Major thermal injury induces the activation of an inflammatory cascade that contributes to the development of subsequent immunosuppression, increased susceptibility to sepsis and multiple organ failure. The productive capacity of macrophages for inflammatory mediators, (i.e., nitric oxide, prostaglandins, TNF-alpha, IL-6 etc.), is profoundly increased post-burn, thereby implicating macrophages in the development of the post-burn immunosuppression. This review will focus on recent findings with regards to the role of macrophages in the development of post-burn immunosuppression with particular emphasis on the role of nitric oxide and prostaglandins. 相似文献
9.
Wang P Ba ZF Jarrar D Cioffi WG Bland KI Chaudry IH 《Archives of surgery (Chicago, Ill. : 1960)》1999,134(4):394-401
BACKGROUND: Although adrenal insufficiency may not occur with moderate hypotension, it does occur with severe hemorrhage. Since hepatocellular function is depressed following severe hemorrhage, it remains unknown whether the liver plays any role in regulating adrenal function after trauma and hemorrhagic shock. HYPOTHESIS: Hepatic 11beta-hydroxysteroid dehydrogenase (11beta-HSD), a microsomal enzyme responsible for the degradation of bioactive corticosterone, plays a major role in the development of adrenal insufficiency following trauma and severe hemorrhage. DESIGN, INTERVENTIONS, AND MAIN OUTCOME MEASURES: Male rats underwent laparotomy to induce trauma before hemorrhage. They were then bled to and maintained at a blood pressure of 40 mm Hg until 40% of the maximal bleed-out volume was returned in the form of Ringer lactate. The rats were then resuscitated with 4 times the volume of maximal bleed-out with Ringer lactate during a 60-minute period. Plasma levels of corticosterone and corticotropin were measured at various intervals. In additional groups, corticotropin-induced corticosterone release, adrenal contents of corticosterone and cyclic adenosine monophosphate (cAMP), hepatic 11beta-HSD activity, and plasma levels of corticosterone-binding globulin were determined at 1.5 hours after resuscitation. Moreover, a model of moderate hypotension (blood pressure, 80 mm Hg) was used to determine whether adrenal function is depressed under such conditions. RESULTS: At the time of maximal bleed-out, plasma corticosterone and corticotropin levels increased by 245% (P<.001) and 293% (P<.001), respectively. Despite corticotropin levels being similar to those of the animals undergoing sham operation after resuscitation, corticosterone levels in hemorrhaged animals remained elevated up to 4 hours after resuscitation (by 158%-207%; P<.001). In addition, corticotropin-induced corticosterone release decreased by 78% at 1.5 hours after resuscitation (P = .009). In contrast, moderate hypotension did not reduce corticotropin-induced corticosterone release. Adrenal corticosterone content and cAMP levels (i.e., the second messenger of corticotropin action) decreased by 55% (P<.001) and 25% (P = .03), respectively. Hepatic 11beta-HSD activity decreased significantly at 1.5 hours after resuscitation (P<.001). CONCLUSIONS: Sustained increase in plasma corticosterone levels following hemorrhage and resuscitation may be, in part, due to the decreased hepatic 11beta-HSD activity. The high level of corticosterone negatively regulates corticotropin release, further reducing adrenal responsiveness to corticotropin stimulation. Thus, the liver appears to play an important role in regulating adrenal function following trauma and severe hemorrhage. 相似文献
10.
Insight into the mechanism by which estradiol improves organ functions after trauma-hemorrhage 总被引:3,自引:0,他引:3
BACKGROUND: Recent studies have indicated that female rodents with high levels of estradiol (proestrus) have better organ functions after trauma-hemorrhage than females with low estradiol levels (estrus) or male animals. However, the precise role of estrogens in maintaining organ function after hemorrhage remains unknown. METHODS: Adult female Sprague-Dawley rats were ovariectomized 14 days before the experiment to decrease circulating levels of estradiol. Animals underwent laparotomy to induce tissue trauma and were then bled to and maintained at a mean arterial pressure of 40 mm Hg until 40% of the maximal bleed-out volume was returned in the form of Ringer's lactate. Resuscitation was carried out with 4 times the volume of maximal bleed-out with Ringer's lactate during a period of 1 hour. 17beta-Estradiol (E2, 1 mg/kg body weight intravenously) with or without a specific estrogen receptor antagonist ICI 182,780 (3 mg/kg body weight intraperitoneally) was given at the beginning of resuscitation. At 24 hours after hemorrhage and resuscitation, cardiovascular and hepatocellular functions (ie, the maximal velocity and overall efficiency of indocyanine green clearance) were determined. Plasma E2 was also assayed. The effects of ovariectomy and E2 administration on uterine weight were measured in additional groups of animals. RESULTS: The results indicate that cardiovascular and hepatocellular organ functions were significantly depressed after trauma-hemorrhage and were restored in animals receiving E2. However, simultaneous administration of its specific receptor antagonist abolished the salutary effects of E2 treatment despite high circulating levels of E2. Uterine weight decreased at 14 days after ovariectomy, which was partially restored with a single dose of E2. CONCLUSIONS: Administration of 17beta-estradiol should be considered a novel and safe adjunct for ameliorating hemorrhage-induced organ dysfunctions in ovariectomized and postmenopausal women because of their low estradiol levels. 相似文献